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v4.6
 
   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
   4 *
   5 * This copyrighted material is made available to anyone wishing to use,
   6 * modify, copy, or redistribute it subject to the terms and conditions
   7 * of the GNU General Public License version 2.
   8 */
   9
  10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12#include <linux/slab.h>
  13#include <linux/spinlock.h>
  14#include <linux/completion.h>
  15#include <linux/buffer_head.h>
  16#include <linux/fs.h>
  17#include <linux/gfs2_ondisk.h>
  18#include <linux/prefetch.h>
  19#include <linux/blkdev.h>
  20#include <linux/rbtree.h>
  21#include <linux/random.h>
  22
  23#include "gfs2.h"
  24#include "incore.h"
  25#include "glock.h"
  26#include "glops.h"
  27#include "lops.h"
  28#include "meta_io.h"
  29#include "quota.h"
  30#include "rgrp.h"
  31#include "super.h"
  32#include "trans.h"
  33#include "util.h"
  34#include "log.h"
  35#include "inode.h"
  36#include "trace_gfs2.h"
 
  37
  38#define BFITNOENT ((u32)~0)
  39#define NO_BLOCK ((u64)~0)
  40
  41#if BITS_PER_LONG == 32
  42#define LBITMASK   (0x55555555UL)
  43#define LBITSKIP55 (0x55555555UL)
  44#define LBITSKIP00 (0x00000000UL)
  45#else
  46#define LBITMASK   (0x5555555555555555UL)
  47#define LBITSKIP55 (0x5555555555555555UL)
  48#define LBITSKIP00 (0x0000000000000000UL)
  49#endif
 
 
 
 
 
 
 
 
  50
  51/*
  52 * These routines are used by the resource group routines (rgrp.c)
  53 * to keep track of block allocation.  Each block is represented by two
  54 * bits.  So, each byte represents GFS2_NBBY (i.e. 4) blocks.
  55 *
  56 * 0 = Free
  57 * 1 = Used (not metadata)
  58 * 2 = Unlinked (still in use) inode
  59 * 3 = Used (metadata)
  60 */
  61
  62struct gfs2_extent {
  63	struct gfs2_rbm rbm;
  64	u32 len;
  65};
  66
  67static const char valid_change[16] = {
  68	        /* current */
  69	/* n */ 0, 1, 1, 1,
  70	/* e */ 1, 0, 0, 0,
  71	/* w */ 0, 0, 0, 1,
  72	        1, 0, 0, 0
  73};
  74
  75static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
  76			 const struct gfs2_inode *ip, bool nowrap,
  77			 const struct gfs2_alloc_parms *ap);
  78
  79
  80/**
  81 * gfs2_setbit - Set a bit in the bitmaps
  82 * @rbm: The position of the bit to set
  83 * @do_clone: Also set the clone bitmap, if it exists
  84 * @new_state: the new state of the block
  85 *
  86 */
  87
  88static inline void gfs2_setbit(const struct gfs2_rbm *rbm, bool do_clone,
  89			       unsigned char new_state)
  90{
  91	unsigned char *byte1, *byte2, *end, cur_state;
  92	struct gfs2_bitmap *bi = rbm_bi(rbm);
  93	unsigned int buflen = bi->bi_len;
  94	const unsigned int bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
  95
  96	byte1 = bi->bi_bh->b_data + bi->bi_offset + (rbm->offset / GFS2_NBBY);
  97	end = bi->bi_bh->b_data + bi->bi_offset + buflen;
  98
  99	BUG_ON(byte1 >= end);
 100
 101	cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
 102
 103	if (unlikely(!valid_change[new_state * 4 + cur_state])) {
 104		pr_warn("buf_blk = 0x%x old_state=%d, new_state=%d\n",
 
 
 105			rbm->offset, cur_state, new_state);
 106		pr_warn("rgrp=0x%llx bi_start=0x%x\n",
 107			(unsigned long long)rbm->rgd->rd_addr, bi->bi_start);
 108		pr_warn("bi_offset=0x%x bi_len=0x%x\n",
 109			bi->bi_offset, bi->bi_len);
 
 
 110		dump_stack();
 111		gfs2_consist_rgrpd(rbm->rgd);
 112		return;
 113	}
 114	*byte1 ^= (cur_state ^ new_state) << bit;
 115
 116	if (do_clone && bi->bi_clone) {
 117		byte2 = bi->bi_clone + bi->bi_offset + (rbm->offset / GFS2_NBBY);
 118		cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
 119		*byte2 ^= (cur_state ^ new_state) << bit;
 120	}
 121}
 122
 123/**
 124 * gfs2_testbit - test a bit in the bitmaps
 125 * @rbm: The bit to test
 
 
 
 
 126 *
 127 * Returns: The two bit block state of the requested bit
 128 */
 129
 130static inline u8 gfs2_testbit(const struct gfs2_rbm *rbm)
 131{
 132	struct gfs2_bitmap *bi = rbm_bi(rbm);
 133	const u8 *buffer = bi->bi_bh->b_data + bi->bi_offset;
 134	const u8 *byte;
 135	unsigned int bit;
 136
 
 
 
 
 
 137	byte = buffer + (rbm->offset / GFS2_NBBY);
 138	bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
 139
 140	return (*byte >> bit) & GFS2_BIT_MASK;
 141}
 142
 143/**
 144 * gfs2_bit_search
 145 * @ptr: Pointer to bitmap data
 146 * @mask: Mask to use (normally 0x55555.... but adjusted for search start)
 147 * @state: The state we are searching for
 148 *
 149 * We xor the bitmap data with a patter which is the bitwise opposite
 150 * of what we are looking for, this gives rise to a pattern of ones
 151 * wherever there is a match. Since we have two bits per entry, we
 152 * take this pattern, shift it down by one place and then and it with
 153 * the original. All the even bit positions (0,2,4, etc) then represent
 154 * successful matches, so we mask with 0x55555..... to remove the unwanted
 155 * odd bit positions.
 156 *
 157 * This allows searching of a whole u64 at once (32 blocks) with a
 158 * single test (on 64 bit arches).
 159 */
 160
 161static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state)
 162{
 163	u64 tmp;
 164	static const u64 search[] = {
 165		[0] = 0xffffffffffffffffULL,
 166		[1] = 0xaaaaaaaaaaaaaaaaULL,
 167		[2] = 0x5555555555555555ULL,
 168		[3] = 0x0000000000000000ULL,
 169	};
 170	tmp = le64_to_cpu(*ptr) ^ search[state];
 171	tmp &= (tmp >> 1);
 172	tmp &= mask;
 173	return tmp;
 174}
 175
 176/**
 177 * rs_cmp - multi-block reservation range compare
 178 * @blk: absolute file system block number of the new reservation
 179 * @len: number of blocks in the new reservation
 180 * @rs: existing reservation to compare against
 181 *
 182 * returns: 1 if the block range is beyond the reach of the reservation
 183 *         -1 if the block range is before the start of the reservation
 184 *          0 if the block range overlaps with the reservation
 185 */
 186static inline int rs_cmp(u64 blk, u32 len, struct gfs2_blkreserv *rs)
 187{
 188	u64 startblk = gfs2_rbm_to_block(&rs->rs_rbm);
 189
 190	if (blk >= startblk + rs->rs_free)
 191		return 1;
 192	if (blk + len - 1 < startblk)
 193		return -1;
 194	return 0;
 195}
 196
 197/**
 198 * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
 199 *       a block in a given allocation state.
 200 * @buf: the buffer that holds the bitmaps
 201 * @len: the length (in bytes) of the buffer
 202 * @goal: start search at this block's bit-pair (within @buffer)
 203 * @state: GFS2_BLKST_XXX the state of the block we're looking for.
 204 *
 205 * Scope of @goal and returned block number is only within this bitmap buffer,
 206 * not entire rgrp or filesystem.  @buffer will be offset from the actual
 207 * beginning of a bitmap block buffer, skipping any header structures, but
 208 * headers are always a multiple of 64 bits long so that the buffer is
 209 * always aligned to a 64 bit boundary.
 210 *
 211 * The size of the buffer is in bytes, but is it assumed that it is
 212 * always ok to read a complete multiple of 64 bits at the end
 213 * of the block in case the end is no aligned to a natural boundary.
 214 *
 215 * Return: the block number (bitmap buffer scope) that was found
 216 */
 217
 218static u32 gfs2_bitfit(const u8 *buf, const unsigned int len,
 219		       u32 goal, u8 state)
 220{
 221	u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1);
 222	const __le64 *ptr = ((__le64 *)buf) + (goal >> 5);
 223	const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64)));
 224	u64 tmp;
 225	u64 mask = 0x5555555555555555ULL;
 226	u32 bit;
 227
 228	/* Mask off bits we don't care about at the start of the search */
 229	mask <<= spoint;
 230	tmp = gfs2_bit_search(ptr, mask, state);
 231	ptr++;
 232	while(tmp == 0 && ptr < end) {
 233		tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state);
 234		ptr++;
 235	}
 236	/* Mask off any bits which are more than len bytes from the start */
 237	if (ptr == end && (len & (sizeof(u64) - 1)))
 238		tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1))));
 239	/* Didn't find anything, so return */
 240	if (tmp == 0)
 241		return BFITNOENT;
 242	ptr--;
 243	bit = __ffs64(tmp);
 244	bit /= 2;	/* two bits per entry in the bitmap */
 245	return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit;
 246}
 247
 248/**
 249 * gfs2_rbm_from_block - Set the rbm based upon rgd and block number
 250 * @rbm: The rbm with rgd already set correctly
 251 * @block: The block number (filesystem relative)
 252 *
 253 * This sets the bi and offset members of an rbm based on a
 254 * resource group and a filesystem relative block number. The
 255 * resource group must be set in the rbm on entry, the bi and
 256 * offset members will be set by this function.
 257 *
 258 * Returns: 0 on success, or an error code
 259 */
 260
 261static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block)
 262{
 263	u64 rblock = block - rbm->rgd->rd_data0;
 264
 265	if (WARN_ON_ONCE(rblock > UINT_MAX))
 266		return -EINVAL;
 267	if (block >= rbm->rgd->rd_data0 + rbm->rgd->rd_data)
 268		return -E2BIG;
 269
 270	rbm->bii = 0;
 271	rbm->offset = (u32)(rblock);
 272	/* Check if the block is within the first block */
 273	if (rbm->offset < rbm_bi(rbm)->bi_blocks)
 274		return 0;
 275
 276	/* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */
 277	rbm->offset += (sizeof(struct gfs2_rgrp) -
 278			sizeof(struct gfs2_meta_header)) * GFS2_NBBY;
 279	rbm->bii = rbm->offset / rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 280	rbm->offset -= rbm->bii * rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 281	return 0;
 282}
 283
 284/**
 285 * gfs2_rbm_incr - increment an rbm structure
 286 * @rbm: The rbm with rgd already set correctly
 
 287 *
 288 * This function takes an existing rbm structure and increments it to the next
 289 * viable block offset.
 290 *
 291 * Returns: If incrementing the offset would cause the rbm to go past the
 292 *          end of the rgrp, true is returned, otherwise false.
 293 *
 
 294 */
 295
 296static bool gfs2_rbm_incr(struct gfs2_rbm *rbm)
 297{
 298	if (rbm->offset + 1 < rbm_bi(rbm)->bi_blocks) { /* in the same bitmap */
 299		rbm->offset++;
 
 
 
 300		return false;
 301	}
 302	if (rbm->bii == rbm->rgd->rd_length - 1) /* at the last bitmap */
 303		return true;
 304
 305	rbm->offset = 0;
 306	rbm->bii++;
 307	return false;
 
 
 
 
 
 
 
 
 308}
 309
 310/**
 311 * gfs2_unaligned_extlen - Look for free blocks which are not byte aligned
 312 * @rbm: Position to search (value/result)
 313 * @n_unaligned: Number of unaligned blocks to check
 314 * @len: Decremented for each block found (terminate on zero)
 315 *
 316 * Returns: true if a non-free block is encountered
 
 317 */
 318
 319static bool gfs2_unaligned_extlen(struct gfs2_rbm *rbm, u32 n_unaligned, u32 *len)
 320{
 321	u32 n;
 322	u8 res;
 323
 324	for (n = 0; n < n_unaligned; n++) {
 325		res = gfs2_testbit(rbm);
 326		if (res != GFS2_BLKST_FREE)
 327			return true;
 328		(*len)--;
 329		if (*len == 0)
 330			return true;
 331		if (gfs2_rbm_incr(rbm))
 332			return true;
 333	}
 334
 335	return false;
 336}
 337
 338/**
 339 * gfs2_free_extlen - Return extent length of free blocks
 340 * @rrbm: Starting position
 341 * @len: Max length to check
 342 *
 343 * Starting at the block specified by the rbm, see how many free blocks
 344 * there are, not reading more than len blocks ahead. This can be done
 345 * using memchr_inv when the blocks are byte aligned, but has to be done
 346 * on a block by block basis in case of unaligned blocks. Also this
 347 * function can cope with bitmap boundaries (although it must stop on
 348 * a resource group boundary)
 349 *
 350 * Returns: Number of free blocks in the extent
 351 */
 352
 353static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len)
 354{
 355	struct gfs2_rbm rbm = *rrbm;
 356	u32 n_unaligned = rbm.offset & 3;
 357	u32 size = len;
 358	u32 bytes;
 359	u32 chunk_size;
 360	u8 *ptr, *start, *end;
 361	u64 block;
 362	struct gfs2_bitmap *bi;
 363
 364	if (n_unaligned &&
 365	    gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len))
 366		goto out;
 367
 368	n_unaligned = len & 3;
 369	/* Start is now byte aligned */
 370	while (len > 3) {
 371		bi = rbm_bi(&rbm);
 372		start = bi->bi_bh->b_data;
 373		if (bi->bi_clone)
 374			start = bi->bi_clone;
 375		end = start + bi->bi_bh->b_size;
 376		start += bi->bi_offset;
 
 377		BUG_ON(rbm.offset & 3);
 378		start += (rbm.offset / GFS2_NBBY);
 379		bytes = min_t(u32, len / GFS2_NBBY, (end - start));
 380		ptr = memchr_inv(start, 0, bytes);
 381		chunk_size = ((ptr == NULL) ? bytes : (ptr - start));
 382		chunk_size *= GFS2_NBBY;
 383		BUG_ON(len < chunk_size);
 384		len -= chunk_size;
 385		block = gfs2_rbm_to_block(&rbm);
 386		if (gfs2_rbm_from_block(&rbm, block + chunk_size)) {
 387			n_unaligned = 0;
 388			break;
 389		}
 390		if (ptr) {
 391			n_unaligned = 3;
 392			break;
 393		}
 394		n_unaligned = len & 3;
 395	}
 396
 397	/* Deal with any bits left over at the end */
 398	if (n_unaligned)
 399		gfs2_unaligned_extlen(&rbm, n_unaligned, &len);
 400out:
 401	return size - len;
 402}
 403
 404/**
 405 * gfs2_bitcount - count the number of bits in a certain state
 406 * @rgd: the resource group descriptor
 407 * @buffer: the buffer that holds the bitmaps
 408 * @buflen: the length (in bytes) of the buffer
 409 * @state: the state of the block we're looking for
 410 *
 411 * Returns: The number of bits
 412 */
 413
 414static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer,
 415			 unsigned int buflen, u8 state)
 416{
 417	const u8 *byte = buffer;
 418	const u8 *end = buffer + buflen;
 419	const u8 state1 = state << 2;
 420	const u8 state2 = state << 4;
 421	const u8 state3 = state << 6;
 422	u32 count = 0;
 423
 424	for (; byte < end; byte++) {
 425		if (((*byte) & 0x03) == state)
 426			count++;
 427		if (((*byte) & 0x0C) == state1)
 428			count++;
 429		if (((*byte) & 0x30) == state2)
 430			count++;
 431		if (((*byte) & 0xC0) == state3)
 432			count++;
 433	}
 434
 435	return count;
 436}
 437
 438/**
 439 * gfs2_rgrp_verify - Verify that a resource group is consistent
 440 * @rgd: the rgrp
 441 *
 442 */
 443
 444void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
 445{
 446	struct gfs2_sbd *sdp = rgd->rd_sbd;
 447	struct gfs2_bitmap *bi = NULL;
 448	u32 length = rgd->rd_length;
 449	u32 count[4], tmp;
 450	int buf, x;
 451
 452	memset(count, 0, 4 * sizeof(u32));
 453
 454	/* Count # blocks in each of 4 possible allocation states */
 455	for (buf = 0; buf < length; buf++) {
 456		bi = rgd->rd_bits + buf;
 457		for (x = 0; x < 4; x++)
 458			count[x] += gfs2_bitcount(rgd,
 459						  bi->bi_bh->b_data +
 460						  bi->bi_offset,
 461						  bi->bi_len, x);
 462	}
 463
 464	if (count[0] != rgd->rd_free) {
 465		if (gfs2_consist_rgrpd(rgd))
 466			fs_err(sdp, "free data mismatch:  %u != %u\n",
 467			       count[0], rgd->rd_free);
 468		return;
 469	}
 470
 471	tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes;
 472	if (count[1] != tmp) {
 473		if (gfs2_consist_rgrpd(rgd))
 474			fs_err(sdp, "used data mismatch:  %u != %u\n",
 475			       count[1], tmp);
 476		return;
 477	}
 478
 479	if (count[2] + count[3] != rgd->rd_dinodes) {
 480		if (gfs2_consist_rgrpd(rgd))
 481			fs_err(sdp, "used metadata mismatch:  %u != %u\n",
 482			       count[2] + count[3], rgd->rd_dinodes);
 483		return;
 484	}
 485}
 486
 487static inline int rgrp_contains_block(struct gfs2_rgrpd *rgd, u64 block)
 488{
 489	u64 first = rgd->rd_data0;
 490	u64 last = first + rgd->rd_data;
 491	return first <= block && block < last;
 492}
 493
 494/**
 495 * gfs2_blk2rgrpd - Find resource group for a given data/meta block number
 496 * @sdp: The GFS2 superblock
 497 * @blk: The data block number
 498 * @exact: True if this needs to be an exact match
 499 *
 
 
 
 
 
 
 
 500 * Returns: The resource group, or NULL if not found
 501 */
 502
 503struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact)
 504{
 505	struct rb_node *n, *next;
 506	struct gfs2_rgrpd *cur;
 507
 508	spin_lock(&sdp->sd_rindex_spin);
 509	n = sdp->sd_rindex_tree.rb_node;
 510	while (n) {
 511		cur = rb_entry(n, struct gfs2_rgrpd, rd_node);
 512		next = NULL;
 513		if (blk < cur->rd_addr)
 514			next = n->rb_left;
 515		else if (blk >= cur->rd_data0 + cur->rd_data)
 516			next = n->rb_right;
 517		if (next == NULL) {
 518			spin_unlock(&sdp->sd_rindex_spin);
 519			if (exact) {
 520				if (blk < cur->rd_addr)
 521					return NULL;
 522				if (blk >= cur->rd_data0 + cur->rd_data)
 523					return NULL;
 524			}
 525			return cur;
 526		}
 527		n = next;
 528	}
 529	spin_unlock(&sdp->sd_rindex_spin);
 530
 531	return NULL;
 532}
 533
 534/**
 535 * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
 536 * @sdp: The GFS2 superblock
 537 *
 538 * Returns: The first rgrp in the filesystem
 539 */
 540
 541struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
 542{
 543	const struct rb_node *n;
 544	struct gfs2_rgrpd *rgd;
 545
 546	spin_lock(&sdp->sd_rindex_spin);
 547	n = rb_first(&sdp->sd_rindex_tree);
 548	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 549	spin_unlock(&sdp->sd_rindex_spin);
 550
 551	return rgd;
 552}
 553
 554/**
 555 * gfs2_rgrpd_get_next - get the next RG
 556 * @rgd: the resource group descriptor
 557 *
 558 * Returns: The next rgrp
 559 */
 560
 561struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
 562{
 563	struct gfs2_sbd *sdp = rgd->rd_sbd;
 564	const struct rb_node *n;
 565
 566	spin_lock(&sdp->sd_rindex_spin);
 567	n = rb_next(&rgd->rd_node);
 568	if (n == NULL)
 569		n = rb_first(&sdp->sd_rindex_tree);
 570
 571	if (unlikely(&rgd->rd_node == n)) {
 572		spin_unlock(&sdp->sd_rindex_spin);
 573		return NULL;
 574	}
 575	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 576	spin_unlock(&sdp->sd_rindex_spin);
 577	return rgd;
 578}
 579
 580void check_and_update_goal(struct gfs2_inode *ip)
 581{
 582	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 583	if (!ip->i_goal || gfs2_blk2rgrpd(sdp, ip->i_goal, 1) == NULL)
 584		ip->i_goal = ip->i_no_addr;
 585}
 586
 587void gfs2_free_clones(struct gfs2_rgrpd *rgd)
 588{
 589	int x;
 590
 591	for (x = 0; x < rgd->rd_length; x++) {
 592		struct gfs2_bitmap *bi = rgd->rd_bits + x;
 593		kfree(bi->bi_clone);
 594		bi->bi_clone = NULL;
 595	}
 596}
 597
 598/**
 599 * gfs2_rsqa_alloc - make sure we have a reservation assigned to the inode
 600 *                 plus a quota allocations data structure, if necessary
 601 * @ip: the inode for this reservation
 602 */
 603int gfs2_rsqa_alloc(struct gfs2_inode *ip)
 604{
 605	return gfs2_qa_alloc(ip);
 606}
 607
 608static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs)
 609{
 610	gfs2_print_dbg(seq, "  B: n:%llu s:%llu b:%u f:%u\n",
 611		       (unsigned long long)rs->rs_inum,
 612		       (unsigned long long)gfs2_rbm_to_block(&rs->rs_rbm),
 613		       rs->rs_rbm.offset, rs->rs_free);
 614}
 615
 616/**
 617 * __rs_deltree - remove a multi-block reservation from the rgd tree
 618 * @rs: The reservation to remove
 619 *
 620 */
 621static void __rs_deltree(struct gfs2_blkreserv *rs)
 622{
 623	struct gfs2_rgrpd *rgd;
 624
 625	if (!gfs2_rs_active(rs))
 626		return;
 627
 628	rgd = rs->rs_rbm.rgd;
 629	trace_gfs2_rs(rs, TRACE_RS_TREEDEL);
 630	rb_erase(&rs->rs_node, &rgd->rd_rstree);
 631	RB_CLEAR_NODE(&rs->rs_node);
 632
 633	if (rs->rs_free) {
 634		struct gfs2_bitmap *bi = rbm_bi(&rs->rs_rbm);
 
 
 635
 636		/* return reserved blocks to the rgrp */
 637		BUG_ON(rs->rs_rbm.rgd->rd_reserved < rs->rs_free);
 638		rs->rs_rbm.rgd->rd_reserved -= rs->rs_free;
 639		/* The rgrp extent failure point is likely not to increase;
 640		   it will only do so if the freed blocks are somehow
 641		   contiguous with a span of free blocks that follows. Still,
 642		   it will force the number to be recalculated later. */
 643		rgd->rd_extfail_pt += rs->rs_free;
 644		rs->rs_free = 0;
 645		clear_bit(GBF_FULL, &bi->bi_flags);
 646	}
 647}
 648
 649/**
 650 * gfs2_rs_deltree - remove a multi-block reservation from the rgd tree
 651 * @rs: The reservation to remove
 652 *
 653 */
 654void gfs2_rs_deltree(struct gfs2_blkreserv *rs)
 655{
 656	struct gfs2_rgrpd *rgd;
 657
 658	rgd = rs->rs_rbm.rgd;
 659	if (rgd) {
 660		spin_lock(&rgd->rd_rsspin);
 661		__rs_deltree(rs);
 
 662		spin_unlock(&rgd->rd_rsspin);
 663	}
 664}
 665
 666/**
 667 * gfs2_rsqa_delete - delete a multi-block reservation and quota allocation
 668 * @ip: The inode for this reservation
 669 * @wcount: The inode's write count, or NULL
 670 *
 671 */
 672void gfs2_rsqa_delete(struct gfs2_inode *ip, atomic_t *wcount)
 673{
 
 
 674	down_write(&ip->i_rw_mutex);
 675	if ((wcount == NULL) || (atomic_read(wcount) <= 1)) {
 676		gfs2_rs_deltree(&ip->i_res);
 677		BUG_ON(ip->i_res.rs_free);
 678	}
 679	up_write(&ip->i_rw_mutex);
 680	gfs2_qa_delete(ip, wcount);
 681}
 682
 683/**
 684 * return_all_reservations - return all reserved blocks back to the rgrp.
 685 * @rgd: the rgrp that needs its space back
 686 *
 687 * We previously reserved a bunch of blocks for allocation. Now we need to
 688 * give them back. This leave the reservation structures in tact, but removes
 689 * all of their corresponding "no-fly zones".
 690 */
 691static void return_all_reservations(struct gfs2_rgrpd *rgd)
 692{
 693	struct rb_node *n;
 694	struct gfs2_blkreserv *rs;
 695
 696	spin_lock(&rgd->rd_rsspin);
 697	while ((n = rb_first(&rgd->rd_rstree))) {
 698		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
 699		__rs_deltree(rs);
 700	}
 701	spin_unlock(&rgd->rd_rsspin);
 702}
 703
 704void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
 705{
 706	struct rb_node *n;
 707	struct gfs2_rgrpd *rgd;
 708	struct gfs2_glock *gl;
 709
 710	while ((n = rb_first(&sdp->sd_rindex_tree))) {
 711		rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 712		gl = rgd->rd_gl;
 713
 714		rb_erase(n, &sdp->sd_rindex_tree);
 715
 716		if (gl) {
 717			spin_lock(&gl->gl_lockref.lock);
 718			gl->gl_object = NULL;
 719			spin_unlock(&gl->gl_lockref.lock);
 720			gfs2_glock_add_to_lru(gl);
 
 
 721			gfs2_glock_put(gl);
 722		}
 723
 724		gfs2_free_clones(rgd);
 725		kfree(rgd->rd_bits);
 726		return_all_reservations(rgd);
 
 
 727		kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 728	}
 729}
 730
 731static void gfs2_rindex_print(const struct gfs2_rgrpd *rgd)
 732{
 733	pr_info("ri_addr = %llu\n", (unsigned long long)rgd->rd_addr);
 734	pr_info("ri_length = %u\n", rgd->rd_length);
 735	pr_info("ri_data0 = %llu\n", (unsigned long long)rgd->rd_data0);
 736	pr_info("ri_data = %u\n", rgd->rd_data);
 737	pr_info("ri_bitbytes = %u\n", rgd->rd_bitbytes);
 738}
 739
 740/**
 741 * gfs2_compute_bitstructs - Compute the bitmap sizes
 742 * @rgd: The resource group descriptor
 743 *
 744 * Calculates bitmap descriptors, one for each block that contains bitmap data
 745 *
 746 * Returns: errno
 747 */
 748
 749static int compute_bitstructs(struct gfs2_rgrpd *rgd)
 750{
 751	struct gfs2_sbd *sdp = rgd->rd_sbd;
 752	struct gfs2_bitmap *bi;
 753	u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */
 754	u32 bytes_left, bytes;
 755	int x;
 756
 757	if (!length)
 758		return -EINVAL;
 759
 760	rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS);
 761	if (!rgd->rd_bits)
 762		return -ENOMEM;
 763
 764	bytes_left = rgd->rd_bitbytes;
 765
 766	for (x = 0; x < length; x++) {
 767		bi = rgd->rd_bits + x;
 768
 769		bi->bi_flags = 0;
 770		/* small rgrp; bitmap stored completely in header block */
 771		if (length == 1) {
 772			bytes = bytes_left;
 773			bi->bi_offset = sizeof(struct gfs2_rgrp);
 774			bi->bi_start = 0;
 775			bi->bi_len = bytes;
 776			bi->bi_blocks = bytes * GFS2_NBBY;
 777		/* header block */
 778		} else if (x == 0) {
 779			bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
 780			bi->bi_offset = sizeof(struct gfs2_rgrp);
 781			bi->bi_start = 0;
 782			bi->bi_len = bytes;
 783			bi->bi_blocks = bytes * GFS2_NBBY;
 784		/* last block */
 785		} else if (x + 1 == length) {
 786			bytes = bytes_left;
 787			bi->bi_offset = sizeof(struct gfs2_meta_header);
 788			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 789			bi->bi_len = bytes;
 790			bi->bi_blocks = bytes * GFS2_NBBY;
 791		/* other blocks */
 792		} else {
 793			bytes = sdp->sd_sb.sb_bsize -
 794				sizeof(struct gfs2_meta_header);
 795			bi->bi_offset = sizeof(struct gfs2_meta_header);
 796			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 797			bi->bi_len = bytes;
 798			bi->bi_blocks = bytes * GFS2_NBBY;
 799		}
 800
 801		bytes_left -= bytes;
 802	}
 803
 804	if (bytes_left) {
 805		gfs2_consist_rgrpd(rgd);
 806		return -EIO;
 807	}
 808	bi = rgd->rd_bits + (length - 1);
 809	if ((bi->bi_start + bi->bi_len) * GFS2_NBBY != rgd->rd_data) {
 810		if (gfs2_consist_rgrpd(rgd)) {
 811			gfs2_rindex_print(rgd);
 812			fs_err(sdp, "start=%u len=%u offset=%u\n",
 813			       bi->bi_start, bi->bi_len, bi->bi_offset);
 814		}
 
 
 
 
 
 
 
 
 
 815		return -EIO;
 816	}
 817
 818	return 0;
 819}
 820
 821/**
 822 * gfs2_ri_total - Total up the file system space, according to the rindex.
 823 * @sdp: the filesystem
 824 *
 825 */
 826u64 gfs2_ri_total(struct gfs2_sbd *sdp)
 827{
 828	u64 total_data = 0;	
 829	struct inode *inode = sdp->sd_rindex;
 830	struct gfs2_inode *ip = GFS2_I(inode);
 831	char buf[sizeof(struct gfs2_rindex)];
 832	int error, rgrps;
 833
 834	for (rgrps = 0;; rgrps++) {
 835		loff_t pos = rgrps * sizeof(struct gfs2_rindex);
 836
 837		if (pos + sizeof(struct gfs2_rindex) > i_size_read(inode))
 838			break;
 839		error = gfs2_internal_read(ip, buf, &pos,
 840					   sizeof(struct gfs2_rindex));
 841		if (error != sizeof(struct gfs2_rindex))
 842			break;
 843		total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data);
 844	}
 845	return total_data;
 846}
 847
 848static int rgd_insert(struct gfs2_rgrpd *rgd)
 849{
 850	struct gfs2_sbd *sdp = rgd->rd_sbd;
 851	struct rb_node **newn = &sdp->sd_rindex_tree.rb_node, *parent = NULL;
 852
 853	/* Figure out where to put new node */
 854	while (*newn) {
 855		struct gfs2_rgrpd *cur = rb_entry(*newn, struct gfs2_rgrpd,
 856						  rd_node);
 857
 858		parent = *newn;
 859		if (rgd->rd_addr < cur->rd_addr)
 860			newn = &((*newn)->rb_left);
 861		else if (rgd->rd_addr > cur->rd_addr)
 862			newn = &((*newn)->rb_right);
 863		else
 864			return -EEXIST;
 865	}
 866
 867	rb_link_node(&rgd->rd_node, parent, newn);
 868	rb_insert_color(&rgd->rd_node, &sdp->sd_rindex_tree);
 869	sdp->sd_rgrps++;
 870	return 0;
 871}
 872
 873/**
 874 * read_rindex_entry - Pull in a new resource index entry from the disk
 875 * @ip: Pointer to the rindex inode
 876 *
 877 * Returns: 0 on success, > 0 on EOF, error code otherwise
 878 */
 879
 880static int read_rindex_entry(struct gfs2_inode *ip)
 881{
 882	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 883	const unsigned bsize = sdp->sd_sb.sb_bsize;
 884	loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
 885	struct gfs2_rindex buf;
 886	int error;
 887	struct gfs2_rgrpd *rgd;
 888
 889	if (pos >= i_size_read(&ip->i_inode))
 890		return 1;
 891
 892	error = gfs2_internal_read(ip, (char *)&buf, &pos,
 893				   sizeof(struct gfs2_rindex));
 894
 895	if (error != sizeof(struct gfs2_rindex))
 896		return (error == 0) ? 1 : error;
 897
 898	rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS);
 899	error = -ENOMEM;
 900	if (!rgd)
 901		return error;
 902
 903	rgd->rd_sbd = sdp;
 904	rgd->rd_addr = be64_to_cpu(buf.ri_addr);
 905	rgd->rd_length = be32_to_cpu(buf.ri_length);
 906	rgd->rd_data0 = be64_to_cpu(buf.ri_data0);
 907	rgd->rd_data = be32_to_cpu(buf.ri_data);
 908	rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes);
 909	spin_lock_init(&rgd->rd_rsspin);
 910
 911	error = compute_bitstructs(rgd);
 912	if (error)
 913		goto fail;
 914
 915	error = gfs2_glock_get(sdp, rgd->rd_addr,
 916			       &gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
 917	if (error)
 918		goto fail;
 919
 920	rgd->rd_gl->gl_object = rgd;
 921	rgd->rd_gl->gl_vm.start = (rgd->rd_addr * bsize) & PAGE_MASK;
 922	rgd->rd_gl->gl_vm.end = PAGE_ALIGN((rgd->rd_addr + rgd->rd_length) * bsize) - 1;
 
 923	rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr;
 924	rgd->rd_flags &= ~(GFS2_RDF_UPTODATE | GFS2_RDF_PREFERRED);
 925	if (rgd->rd_data > sdp->sd_max_rg_data)
 926		sdp->sd_max_rg_data = rgd->rd_data;
 927	spin_lock(&sdp->sd_rindex_spin);
 928	error = rgd_insert(rgd);
 929	spin_unlock(&sdp->sd_rindex_spin);
 930	if (!error)
 
 931		return 0;
 
 932
 933	error = 0; /* someone else read in the rgrp; free it and ignore it */
 
 934	gfs2_glock_put(rgd->rd_gl);
 935
 936fail:
 937	kfree(rgd->rd_bits);
 
 938	kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 939	return error;
 940}
 941
 942/**
 943 * set_rgrp_preferences - Run all the rgrps, selecting some we prefer to use
 944 * @sdp: the GFS2 superblock
 945 *
 946 * The purpose of this function is to select a subset of the resource groups
 947 * and mark them as PREFERRED. We do it in such a way that each node prefers
 948 * to use a unique set of rgrps to minimize glock contention.
 949 */
 950static void set_rgrp_preferences(struct gfs2_sbd *sdp)
 951{
 952	struct gfs2_rgrpd *rgd, *first;
 953	int i;
 954
 955	/* Skip an initial number of rgrps, based on this node's journal ID.
 956	   That should start each node out on its own set. */
 957	rgd = gfs2_rgrpd_get_first(sdp);
 958	for (i = 0; i < sdp->sd_lockstruct.ls_jid; i++)
 959		rgd = gfs2_rgrpd_get_next(rgd);
 960	first = rgd;
 961
 962	do {
 963		rgd->rd_flags |= GFS2_RDF_PREFERRED;
 964		for (i = 0; i < sdp->sd_journals; i++) {
 965			rgd = gfs2_rgrpd_get_next(rgd);
 966			if (!rgd || rgd == first)
 967				break;
 968		}
 969	} while (rgd && rgd != first);
 970}
 971
 972/**
 973 * gfs2_ri_update - Pull in a new resource index from the disk
 974 * @ip: pointer to the rindex inode
 975 *
 976 * Returns: 0 on successful update, error code otherwise
 977 */
 978
 979static int gfs2_ri_update(struct gfs2_inode *ip)
 980{
 981	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 982	int error;
 983
 984	do {
 985		error = read_rindex_entry(ip);
 986	} while (error == 0);
 987
 988	if (error < 0)
 989		return error;
 990
 
 
 
 
 991	set_rgrp_preferences(sdp);
 992
 993	sdp->sd_rindex_uptodate = 1;
 994	return 0;
 995}
 996
 997/**
 998 * gfs2_rindex_update - Update the rindex if required
 999 * @sdp: The GFS2 superblock
1000 *
1001 * We grab a lock on the rindex inode to make sure that it doesn't
1002 * change whilst we are performing an operation. We keep this lock
1003 * for quite long periods of time compared to other locks. This
1004 * doesn't matter, since it is shared and it is very, very rarely
1005 * accessed in the exclusive mode (i.e. only when expanding the filesystem).
1006 *
1007 * This makes sure that we're using the latest copy of the resource index
1008 * special file, which might have been updated if someone expanded the
1009 * filesystem (via gfs2_grow utility), which adds new resource groups.
1010 *
1011 * Returns: 0 on succeess, error code otherwise
1012 */
1013
1014int gfs2_rindex_update(struct gfs2_sbd *sdp)
1015{
1016	struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
1017	struct gfs2_glock *gl = ip->i_gl;
1018	struct gfs2_holder ri_gh;
1019	int error = 0;
1020	int unlock_required = 0;
1021
1022	/* Read new copy from disk if we don't have the latest */
1023	if (!sdp->sd_rindex_uptodate) {
1024		if (!gfs2_glock_is_locked_by_me(gl)) {
1025			error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, &ri_gh);
1026			if (error)
1027				return error;
1028			unlock_required = 1;
1029		}
1030		if (!sdp->sd_rindex_uptodate)
1031			error = gfs2_ri_update(ip);
1032		if (unlock_required)
1033			gfs2_glock_dq_uninit(&ri_gh);
1034	}
1035
1036	return error;
1037}
1038
1039static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf)
1040{
1041	const struct gfs2_rgrp *str = buf;
1042	u32 rg_flags;
1043
1044	rg_flags = be32_to_cpu(str->rg_flags);
1045	rg_flags &= ~GFS2_RDF_MASK;
1046	rgd->rd_flags &= GFS2_RDF_MASK;
1047	rgd->rd_flags |= rg_flags;
1048	rgd->rd_free = be32_to_cpu(str->rg_free);
1049	rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes);
1050	rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration);
 
 
 
 
 
 
 
 
 
 
 
 
 
1051}
1052
1053static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf)
1054{
 
1055	struct gfs2_rgrp *str = buf;
 
1056
1057	str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK);
1058	str->rg_free = cpu_to_be32(rgd->rd_free);
1059	str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes);
1060	str->__pad = cpu_to_be32(0);
 
 
 
1061	str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration);
 
 
 
 
 
 
 
1062	memset(&str->rg_reserved, 0, sizeof(str->rg_reserved));
 
1063}
1064
1065static int gfs2_rgrp_lvb_valid(struct gfs2_rgrpd *rgd)
1066{
1067	struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1068	struct gfs2_rgrp *str = (struct gfs2_rgrp *)rgd->rd_bits[0].bi_bh->b_data;
 
 
1069
1070	if (rgl->rl_flags != str->rg_flags || rgl->rl_free != str->rg_free ||
1071	    rgl->rl_dinodes != str->rg_dinodes ||
1072	    rgl->rl_igeneration != str->rg_igeneration)
1073		return 0;
1074	return 1;
1075}
1076
1077static void gfs2_rgrp_ondisk2lvb(struct gfs2_rgrp_lvb *rgl, const void *buf)
1078{
1079	const struct gfs2_rgrp *str = buf;
1080
1081	rgl->rl_magic = cpu_to_be32(GFS2_MAGIC);
1082	rgl->rl_flags = str->rg_flags;
1083	rgl->rl_free = str->rg_free;
1084	rgl->rl_dinodes = str->rg_dinodes;
1085	rgl->rl_igeneration = str->rg_igeneration;
1086	rgl->__pad = 0UL;
1087}
1088
1089static void update_rgrp_lvb_unlinked(struct gfs2_rgrpd *rgd, u32 change)
1090{
1091	struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1092	u32 unlinked = be32_to_cpu(rgl->rl_unlinked) + change;
1093	rgl->rl_unlinked = cpu_to_be32(unlinked);
 
 
 
1094}
1095
1096static u32 count_unlinked(struct gfs2_rgrpd *rgd)
1097{
1098	struct gfs2_bitmap *bi;
1099	const u32 length = rgd->rd_length;
1100	const u8 *buffer = NULL;
1101	u32 i, goal, count = 0;
1102
1103	for (i = 0, bi = rgd->rd_bits; i < length; i++, bi++) {
1104		goal = 0;
1105		buffer = bi->bi_bh->b_data + bi->bi_offset;
1106		WARN_ON(!buffer_uptodate(bi->bi_bh));
1107		while (goal < bi->bi_len * GFS2_NBBY) {
1108			goal = gfs2_bitfit(buffer, bi->bi_len, goal,
1109					   GFS2_BLKST_UNLINKED);
1110			if (goal == BFITNOENT)
1111				break;
1112			count++;
1113			goal++;
1114		}
1115	}
1116
1117	return count;
1118}
1119
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1120
1121/**
1122 * gfs2_rgrp_bh_get - Read in a RG's header and bitmaps
1123 * @rgd: the struct gfs2_rgrpd describing the RG to read in
1124 *
1125 * Read in all of a Resource Group's header and bitmap blocks.
1126 * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps.
1127 *
1128 * Returns: errno
1129 */
1130
1131static int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
1132{
 
1133	struct gfs2_sbd *sdp = rgd->rd_sbd;
1134	struct gfs2_glock *gl = rgd->rd_gl;
1135	unsigned int length = rgd->rd_length;
1136	struct gfs2_bitmap *bi;
1137	unsigned int x, y;
1138	int error;
1139
1140	if (rgd->rd_bits[0].bi_bh != NULL)
1141		return 0;
1142
1143	for (x = 0; x < length; x++) {
1144		bi = rgd->rd_bits + x;
1145		error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, 0, &bi->bi_bh);
1146		if (error)
1147			goto fail;
1148	}
1149
1150	for (y = length; y--;) {
1151		bi = rgd->rd_bits + y;
1152		error = gfs2_meta_wait(sdp, bi->bi_bh);
1153		if (error)
1154			goto fail;
1155		if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB :
1156					      GFS2_METATYPE_RG)) {
1157			error = -EIO;
1158			goto fail;
1159		}
1160	}
1161
1162	if (!(rgd->rd_flags & GFS2_RDF_UPTODATE)) {
1163		for (x = 0; x < length; x++)
1164			clear_bit(GBF_FULL, &rgd->rd_bits[x].bi_flags);
1165		gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
1166		rgd->rd_flags |= (GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1167		rgd->rd_free_clone = rgd->rd_free;
1168		/* max out the rgrp allocation failure point */
1169		rgd->rd_extfail_pt = rgd->rd_free;
1170	}
1171	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) {
1172		rgd->rd_rgl->rl_unlinked = cpu_to_be32(count_unlinked(rgd));
1173		gfs2_rgrp_ondisk2lvb(rgd->rd_rgl,
1174				     rgd->rd_bits[0].bi_bh->b_data);
1175	}
1176	else if (sdp->sd_args.ar_rgrplvb) {
1177		if (!gfs2_rgrp_lvb_valid(rgd)){
1178			gfs2_consist_rgrpd(rgd);
1179			error = -EIO;
1180			goto fail;
1181		}
1182		if (rgd->rd_rgl->rl_unlinked == 0)
1183			rgd->rd_flags &= ~GFS2_RDF_CHECK;
1184	}
1185	return 0;
1186
1187fail:
1188	while (x--) {
1189		bi = rgd->rd_bits + x;
1190		brelse(bi->bi_bh);
1191		bi->bi_bh = NULL;
1192		gfs2_assert_warn(sdp, !bi->bi_clone);
1193	}
1194
1195	return error;
1196}
1197
1198static int update_rgrp_lvb(struct gfs2_rgrpd *rgd)
1199{
1200	u32 rl_flags;
1201
1202	if (rgd->rd_flags & GFS2_RDF_UPTODATE)
1203		return 0;
1204
1205	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic)
1206		return gfs2_rgrp_bh_get(rgd);
1207
1208	rl_flags = be32_to_cpu(rgd->rd_rgl->rl_flags);
1209	rl_flags &= ~GFS2_RDF_MASK;
1210	rgd->rd_flags &= GFS2_RDF_MASK;
1211	rgd->rd_flags |= (rl_flags | GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1212	if (rgd->rd_rgl->rl_unlinked == 0)
1213		rgd->rd_flags &= ~GFS2_RDF_CHECK;
1214	rgd->rd_free = be32_to_cpu(rgd->rd_rgl->rl_free);
 
1215	rgd->rd_free_clone = rgd->rd_free;
 
 
 
1216	rgd->rd_dinodes = be32_to_cpu(rgd->rd_rgl->rl_dinodes);
1217	rgd->rd_igeneration = be64_to_cpu(rgd->rd_rgl->rl_igeneration);
1218	return 0;
1219}
1220
1221int gfs2_rgrp_go_lock(struct gfs2_holder *gh)
1222{
1223	struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1224	struct gfs2_sbd *sdp = rgd->rd_sbd;
1225
1226	if (gh->gh_flags & GL_SKIP && sdp->sd_args.ar_rgrplvb)
1227		return 0;
1228	return gfs2_rgrp_bh_get(rgd);
1229}
1230
1231/**
1232 * gfs2_rgrp_brelse - Release RG bitmaps read in with gfs2_rgrp_bh_get()
1233 * @rgd: The resource group
1234 *
1235 */
1236
1237void gfs2_rgrp_brelse(struct gfs2_rgrpd *rgd)
1238{
1239	int x, length = rgd->rd_length;
1240
1241	for (x = 0; x < length; x++) {
1242		struct gfs2_bitmap *bi = rgd->rd_bits + x;
1243		if (bi->bi_bh) {
1244			brelse(bi->bi_bh);
1245			bi->bi_bh = NULL;
1246		}
1247	}
1248
1249}
1250
1251/**
1252 * gfs2_rgrp_go_unlock - Unlock a rgrp glock
1253 * @gh: The glock holder for the resource group
1254 *
1255 */
1256
1257void gfs2_rgrp_go_unlock(struct gfs2_holder *gh)
1258{
1259	struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1260	int demote_requested = test_bit(GLF_DEMOTE, &gh->gh_gl->gl_flags) |
1261		test_bit(GLF_PENDING_DEMOTE, &gh->gh_gl->gl_flags);
1262
1263	if (rgd && demote_requested)
1264		gfs2_rgrp_brelse(rgd);
1265}
1266
1267int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
1268			     struct buffer_head *bh,
1269			     const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed)
1270{
1271	struct super_block *sb = sdp->sd_vfs;
1272	u64 blk;
1273	sector_t start = 0;
1274	sector_t nr_blks = 0;
1275	int rv;
1276	unsigned int x;
1277	u32 trimmed = 0;
1278	u8 diff;
1279
1280	for (x = 0; x < bi->bi_len; x++) {
1281		const u8 *clone = bi->bi_clone ? bi->bi_clone : bi->bi_bh->b_data;
1282		clone += bi->bi_offset;
1283		clone += x;
1284		if (bh) {
1285			const u8 *orig = bh->b_data + bi->bi_offset + x;
1286			diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1));
1287		} else {
1288			diff = ~(*clone | (*clone >> 1));
1289		}
1290		diff &= 0x55;
1291		if (diff == 0)
1292			continue;
1293		blk = offset + ((bi->bi_start + x) * GFS2_NBBY);
1294		while(diff) {
1295			if (diff & 1) {
1296				if (nr_blks == 0)
1297					goto start_new_extent;
1298				if ((start + nr_blks) != blk) {
1299					if (nr_blks >= minlen) {
1300						rv = sb_issue_discard(sb,
1301							start, nr_blks,
1302							GFP_NOFS, 0);
1303						if (rv)
1304							goto fail;
1305						trimmed += nr_blks;
1306					}
1307					nr_blks = 0;
1308start_new_extent:
1309					start = blk;
1310				}
1311				nr_blks++;
1312			}
1313			diff >>= 2;
1314			blk++;
1315		}
1316	}
1317	if (nr_blks >= minlen) {
1318		rv = sb_issue_discard(sb, start, nr_blks, GFP_NOFS, 0);
1319		if (rv)
1320			goto fail;
1321		trimmed += nr_blks;
1322	}
1323	if (ptrimmed)
1324		*ptrimmed = trimmed;
1325	return 0;
1326
1327fail:
1328	if (sdp->sd_args.ar_discard)
1329		fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem", rv);
1330	sdp->sd_args.ar_discard = 0;
1331	return -EIO;
1332}
1333
1334/**
1335 * gfs2_fitrim - Generate discard requests for unused bits of the filesystem
1336 * @filp: Any file on the filesystem
1337 * @argp: Pointer to the arguments (also used to pass result)
1338 *
1339 * Returns: 0 on success, otherwise error code
1340 */
1341
1342int gfs2_fitrim(struct file *filp, void __user *argp)
1343{
1344	struct inode *inode = file_inode(filp);
1345	struct gfs2_sbd *sdp = GFS2_SB(inode);
1346	struct request_queue *q = bdev_get_queue(sdp->sd_vfs->s_bdev);
1347	struct buffer_head *bh;
1348	struct gfs2_rgrpd *rgd;
1349	struct gfs2_rgrpd *rgd_end;
1350	struct gfs2_holder gh;
1351	struct fstrim_range r;
1352	int ret = 0;
1353	u64 amt;
1354	u64 trimmed = 0;
1355	u64 start, end, minlen;
1356	unsigned int x;
1357	unsigned bs_shift = sdp->sd_sb.sb_bsize_shift;
1358
1359	if (!capable(CAP_SYS_ADMIN))
1360		return -EPERM;
1361
1362	if (!blk_queue_discard(q))
 
 
 
1363		return -EOPNOTSUPP;
1364
1365	if (copy_from_user(&r, argp, sizeof(r)))
1366		return -EFAULT;
1367
1368	ret = gfs2_rindex_update(sdp);
1369	if (ret)
1370		return ret;
1371
1372	start = r.start >> bs_shift;
1373	end = start + (r.len >> bs_shift);
1374	minlen = max_t(u64, r.minlen,
1375		       q->limits.discard_granularity) >> bs_shift;
1376
1377	if (end <= start || minlen > sdp->sd_max_rg_data)
1378		return -EINVAL;
1379
1380	rgd = gfs2_blk2rgrpd(sdp, start, 0);
1381	rgd_end = gfs2_blk2rgrpd(sdp, end, 0);
1382
1383	if ((gfs2_rgrpd_get_first(sdp) == gfs2_rgrpd_get_next(rgd_end))
1384	    && (start > rgd_end->rd_data0 + rgd_end->rd_data))
1385		return -EINVAL; /* start is beyond the end of the fs */
1386
1387	while (1) {
1388
1389		ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
 
1390		if (ret)
1391			goto out;
1392
1393		if (!(rgd->rd_flags & GFS2_RGF_TRIMMED)) {
1394			/* Trim each bitmap in the rgrp */
1395			for (x = 0; x < rgd->rd_length; x++) {
1396				struct gfs2_bitmap *bi = rgd->rd_bits + x;
 
1397				ret = gfs2_rgrp_send_discards(sdp,
1398						rgd->rd_data0, NULL, bi, minlen,
1399						&amt);
 
1400				if (ret) {
1401					gfs2_glock_dq_uninit(&gh);
1402					goto out;
1403				}
1404				trimmed += amt;
1405			}
1406
1407			/* Mark rgrp as having been trimmed */
1408			ret = gfs2_trans_begin(sdp, RES_RG_HDR, 0);
1409			if (ret == 0) {
1410				bh = rgd->rd_bits[0].bi_bh;
 
1411				rgd->rd_flags |= GFS2_RGF_TRIMMED;
1412				gfs2_trans_add_meta(rgd->rd_gl, bh);
1413				gfs2_rgrp_out(rgd, bh->b_data);
1414				gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, bh->b_data);
1415				gfs2_trans_end(sdp);
1416			}
1417		}
1418		gfs2_glock_dq_uninit(&gh);
1419
1420		if (rgd == rgd_end)
1421			break;
1422
1423		rgd = gfs2_rgrpd_get_next(rgd);
1424	}
1425
1426out:
1427	r.len = trimmed << bs_shift;
1428	if (copy_to_user(argp, &r, sizeof(r)))
1429		return -EFAULT;
1430
1431	return ret;
1432}
1433
1434/**
1435 * rs_insert - insert a new multi-block reservation into the rgrp's rb_tree
1436 * @ip: the inode structure
1437 *
1438 */
1439static void rs_insert(struct gfs2_inode *ip)
1440{
1441	struct rb_node **newn, *parent = NULL;
1442	int rc;
1443	struct gfs2_blkreserv *rs = &ip->i_res;
1444	struct gfs2_rgrpd *rgd = rs->rs_rbm.rgd;
1445	u64 fsblock = gfs2_rbm_to_block(&rs->rs_rbm);
1446
1447	BUG_ON(gfs2_rs_active(rs));
1448
1449	spin_lock(&rgd->rd_rsspin);
1450	newn = &rgd->rd_rstree.rb_node;
1451	while (*newn) {
1452		struct gfs2_blkreserv *cur =
1453			rb_entry(*newn, struct gfs2_blkreserv, rs_node);
1454
1455		parent = *newn;
1456		rc = rs_cmp(fsblock, rs->rs_free, cur);
1457		if (rc > 0)
1458			newn = &((*newn)->rb_right);
1459		else if (rc < 0)
1460			newn = &((*newn)->rb_left);
1461		else {
1462			spin_unlock(&rgd->rd_rsspin);
1463			WARN_ON(1);
1464			return;
1465		}
1466	}
1467
1468	rb_link_node(&rs->rs_node, parent, newn);
1469	rb_insert_color(&rs->rs_node, &rgd->rd_rstree);
1470
1471	/* Do our rgrp accounting for the reservation */
1472	rgd->rd_reserved += rs->rs_free; /* blocks reserved */
1473	spin_unlock(&rgd->rd_rsspin);
1474	trace_gfs2_rs(rs, TRACE_RS_INSERT);
1475}
1476
1477/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1478 * rg_mblk_search - find a group of multiple free blocks to form a reservation
1479 * @rgd: the resource group descriptor
1480 * @ip: pointer to the inode for which we're reserving blocks
1481 * @ap: the allocation parameters
1482 *
1483 */
1484
1485static void rg_mblk_search(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip,
1486			   const struct gfs2_alloc_parms *ap)
1487{
1488	struct gfs2_rbm rbm = { .rgd = rgd, };
1489	u64 goal;
1490	struct gfs2_blkreserv *rs = &ip->i_res;
1491	u32 extlen;
1492	u32 free_blocks = rgd->rd_free_clone - rgd->rd_reserved;
1493	int ret;
1494	struct inode *inode = &ip->i_inode;
1495
 
 
 
 
 
 
 
 
 
1496	if (S_ISDIR(inode->i_mode))
1497		extlen = 1;
1498	else {
1499		extlen = max_t(u32, atomic_read(&rs->rs_sizehint), ap->target);
1500		extlen = clamp(extlen, RGRP_RSRV_MINBLKS, free_blocks);
1501	}
1502	if ((rgd->rd_free_clone < rgd->rd_reserved) || (free_blocks < extlen))
1503		return;
1504
1505	/* Find bitmap block that contains bits for goal block */
1506	if (rgrp_contains_block(rgd, ip->i_goal))
1507		goal = ip->i_goal;
1508	else
1509		goal = rgd->rd_last_alloc + rgd->rd_data0;
1510
1511	if (WARN_ON(gfs2_rbm_from_block(&rbm, goal)))
1512		return;
1513
1514	ret = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &extlen, ip, true, ap);
1515	if (ret == 0) {
1516		rs->rs_rbm = rbm;
1517		rs->rs_free = extlen;
1518		rs->rs_inum = ip->i_no_addr;
1519		rs_insert(ip);
1520	} else {
1521		if (goal == rgd->rd_last_alloc + rgd->rd_data0)
1522			rgd->rd_last_alloc = 0;
1523	}
1524}
1525
1526/**
1527 * gfs2_next_unreserved_block - Return next block that is not reserved
1528 * @rgd: The resource group
1529 * @block: The starting block
1530 * @length: The required length
1531 * @ip: Ignore any reservations for this inode
1532 *
1533 * If the block does not appear in any reservation, then return the
1534 * block number unchanged. If it does appear in the reservation, then
1535 * keep looking through the tree of reservations in order to find the
1536 * first block number which is not reserved.
1537 */
1538
1539static u64 gfs2_next_unreserved_block(struct gfs2_rgrpd *rgd, u64 block,
1540				      u32 length,
1541				      const struct gfs2_inode *ip)
1542{
1543	struct gfs2_blkreserv *rs;
1544	struct rb_node *n;
1545	int rc;
1546
1547	spin_lock(&rgd->rd_rsspin);
1548	n = rgd->rd_rstree.rb_node;
1549	while (n) {
1550		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1551		rc = rs_cmp(block, length, rs);
1552		if (rc < 0)
1553			n = n->rb_left;
1554		else if (rc > 0)
1555			n = n->rb_right;
1556		else
1557			break;
1558	}
1559
1560	if (n) {
1561		while ((rs_cmp(block, length, rs) == 0) && (&ip->i_res != rs)) {
1562			block = gfs2_rbm_to_block(&rs->rs_rbm) + rs->rs_free;
1563			n = n->rb_right;
1564			if (n == NULL)
1565				break;
1566			rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1567		}
1568	}
1569
1570	spin_unlock(&rgd->rd_rsspin);
1571	return block;
1572}
1573
1574/**
1575 * gfs2_reservation_check_and_update - Check for reservations during block alloc
1576 * @rbm: The current position in the resource group
1577 * @ip: The inode for which we are searching for blocks
1578 * @minext: The minimum extent length
1579 * @maxext: A pointer to the maximum extent structure
1580 *
1581 * This checks the current position in the rgrp to see whether there is
1582 * a reservation covering this block. If not then this function is a
1583 * no-op. If there is, then the position is moved to the end of the
1584 * contiguous reservation(s) so that we are pointing at the first
1585 * non-reserved block.
1586 *
1587 * Returns: 0 if no reservation, 1 if @rbm has changed, otherwise an error
1588 */
1589
1590static int gfs2_reservation_check_and_update(struct gfs2_rbm *rbm,
1591					     const struct gfs2_inode *ip,
1592					     u32 minext,
1593					     struct gfs2_extent *maxext)
1594{
1595	u64 block = gfs2_rbm_to_block(rbm);
1596	u32 extlen = 1;
1597	u64 nblock;
1598	int ret;
1599
1600	/*
1601	 * If we have a minimum extent length, then skip over any extent
1602	 * which is less than the min extent length in size.
1603	 */
1604	if (minext) {
1605		extlen = gfs2_free_extlen(rbm, minext);
1606		if (extlen <= maxext->len)
1607			goto fail;
1608	}
1609
1610	/*
1611	 * Check the extent which has been found against the reservations
1612	 * and skip if parts of it are already reserved
1613	 */
1614	nblock = gfs2_next_unreserved_block(rbm->rgd, block, extlen, ip);
1615	if (nblock == block) {
1616		if (!minext || extlen >= minext)
1617			return 0;
1618
1619		if (extlen > maxext->len) {
1620			maxext->len = extlen;
1621			maxext->rbm = *rbm;
1622		}
1623fail:
1624		nblock = block + extlen;
 
 
 
1625	}
1626	ret = gfs2_rbm_from_block(rbm, nblock);
1627	if (ret < 0)
1628		return ret;
1629	return 1;
1630}
1631
1632/**
1633 * gfs2_rbm_find - Look for blocks of a particular state
1634 * @rbm: Value/result starting position and final position
1635 * @state: The state which we want to find
1636 * @minext: Pointer to the requested extent length (NULL for a single block)
1637 *          This is updated to be the actual reservation size.
1638 * @ip: If set, check for reservations
1639 * @nowrap: Stop looking at the end of the rgrp, rather than wrapping
1640 *          around until we've reached the starting point.
1641 * @ap: the allocation parameters
1642 *
1643 * Side effects:
1644 * - If looking for free blocks, we set GBF_FULL on each bitmap which
1645 *   has no free blocks in it.
1646 * - If looking for free blocks, we set rd_extfail_pt on each rgrp which
1647 *   has come up short on a free block search.
1648 *
1649 * Returns: 0 on success, -ENOSPC if there is no block of the requested state
1650 */
1651
1652static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
1653			 const struct gfs2_inode *ip, bool nowrap,
1654			 const struct gfs2_alloc_parms *ap)
1655{
 
1656	struct buffer_head *bh;
1657	int initial_bii;
1658	u32 initial_offset;
1659	int first_bii = rbm->bii;
1660	u32 first_offset = rbm->offset;
1661	u32 offset;
1662	u8 *buffer;
1663	int n = 0;
1664	int iters = rbm->rgd->rd_length;
1665	int ret;
1666	struct gfs2_bitmap *bi;
1667	struct gfs2_extent maxext = { .rbm.rgd = rbm->rgd, };
1668
1669	/* If we are not starting at the beginning of a bitmap, then we
1670	 * need to add one to the bitmap count to ensure that we search
1671	 * the starting bitmap twice.
 
1672	 */
1673	if (rbm->offset != 0)
1674		iters++;
1675
1676	while(1) {
1677		bi = rbm_bi(rbm);
1678		if (test_bit(GBF_FULL, &bi->bi_flags) &&
1679		    (state == GFS2_BLKST_FREE))
1680			goto next_bitmap;
1681
1682		bh = bi->bi_bh;
1683		buffer = bh->b_data + bi->bi_offset;
1684		WARN_ON(!buffer_uptodate(bh));
1685		if (state != GFS2_BLKST_UNLINKED && bi->bi_clone)
1686			buffer = bi->bi_clone + bi->bi_offset;
1687		initial_offset = rbm->offset;
1688		offset = gfs2_bitfit(buffer, bi->bi_len, rbm->offset, state);
1689		if (offset == BFITNOENT)
1690			goto bitmap_full;
 
 
1691		rbm->offset = offset;
1692		if (ip == NULL)
1693			return 0;
1694
1695		initial_bii = rbm->bii;
1696		ret = gfs2_reservation_check_and_update(rbm, ip,
1697							minext ? *minext : 0,
1698							&maxext);
1699		if (ret == 0)
1700			return 0;
1701		if (ret > 0) {
1702			n += (rbm->bii - initial_bii);
1703			goto next_iter;
1704		}
1705		if (ret == -E2BIG) {
1706			rbm->bii = 0;
1707			rbm->offset = 0;
1708			n += (rbm->bii - initial_bii);
1709			goto res_covered_end_of_rgrp;
1710		}
1711		return ret;
1712
1713bitmap_full:	/* Mark bitmap as full and fall through */
1714		if ((state == GFS2_BLKST_FREE) && initial_offset == 0)
1715			set_bit(GBF_FULL, &bi->bi_flags);
1716
1717next_bitmap:	/* Find next bitmap in the rgrp */
1718		rbm->offset = 0;
1719		rbm->bii++;
1720		if (rbm->bii == rbm->rgd->rd_length)
1721			rbm->bii = 0;
1722res_covered_end_of_rgrp:
1723		if ((rbm->bii == 0) && nowrap)
1724			break;
1725		n++;
 
 
 
 
1726next_iter:
1727		if (n >= iters)
 
1728			break;
1729	}
1730
1731	if (minext == NULL || state != GFS2_BLKST_FREE)
1732		return -ENOSPC;
1733
1734	/* If the extent was too small, and it's smaller than the smallest
1735	   to have failed before, remember for future reference that it's
1736	   useless to search this rgrp again for this amount or more. */
1737	if ((first_offset == 0) && (first_bii == 0) &&
1738	    (*minext < rbm->rgd->rd_extfail_pt))
1739		rbm->rgd->rd_extfail_pt = *minext;
1740
1741	/* If the maximum extent we found is big enough to fulfill the
1742	   minimum requirements, use it anyway. */
1743	if (maxext.len) {
1744		*rbm = maxext.rbm;
1745		*minext = maxext.len;
1746		return 0;
1747	}
1748
1749	return -ENOSPC;
1750}
1751
1752/**
1753 * try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes
1754 * @rgd: The rgrp
1755 * @last_unlinked: block address of the last dinode we unlinked
1756 * @skip: block address we should explicitly not unlink
1757 *
1758 * Returns: 0 if no error
1759 *          The inode, if one has been found, in inode.
1760 */
1761
1762static void try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked, u64 skip)
1763{
1764	u64 block;
1765	struct gfs2_sbd *sdp = rgd->rd_sbd;
1766	struct gfs2_glock *gl;
1767	struct gfs2_inode *ip;
1768	int error;
1769	int found = 0;
1770	struct gfs2_rbm rbm = { .rgd = rgd, .bii = 0, .offset = 0 };
1771
1772	while (1) {
1773		down_write(&sdp->sd_log_flush_lock);
1774		error = gfs2_rbm_find(&rbm, GFS2_BLKST_UNLINKED, NULL, NULL,
1775				      true, NULL);
1776		up_write(&sdp->sd_log_flush_lock);
1777		if (error == -ENOSPC)
1778			break;
1779		if (WARN_ON_ONCE(error))
1780			break;
1781
1782		block = gfs2_rbm_to_block(&rbm);
1783		if (gfs2_rbm_from_block(&rbm, block + 1))
1784			break;
1785		if (*last_unlinked != NO_BLOCK && block <= *last_unlinked)
1786			continue;
1787		if (block == skip)
1788			continue;
1789		*last_unlinked = block;
1790
1791		error = gfs2_glock_get(sdp, block, &gfs2_iopen_glops, CREATE, &gl);
1792		if (error)
1793			continue;
1794
1795		/* If the inode is already in cache, we can ignore it here
1796		 * because the existing inode disposal code will deal with
1797		 * it when all refs have gone away. Accessing gl_object like
1798		 * this is not safe in general. Here it is ok because we do
1799		 * not dereference the pointer, and we only need an approx
1800		 * answer to whether it is NULL or not.
1801		 */
1802		ip = gl->gl_object;
1803
1804		if (ip || queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
1805			gfs2_glock_put(gl);
1806		else
1807			found++;
1808
1809		/* Limit reclaim to sensible number of tasks */
1810		if (found > NR_CPUS)
1811			return;
1812	}
1813
1814	rgd->rd_flags &= ~GFS2_RDF_CHECK;
1815	return;
1816}
1817
1818/**
1819 * gfs2_rgrp_congested - Use stats to figure out whether an rgrp is congested
1820 * @rgd: The rgrp in question
1821 * @loops: An indication of how picky we can be (0=very, 1=less so)
1822 *
1823 * This function uses the recently added glock statistics in order to
1824 * figure out whether a parciular resource group is suffering from
1825 * contention from multiple nodes. This is done purely on the basis
1826 * of timings, since this is the only data we have to work with and
1827 * our aim here is to reject a resource group which is highly contended
1828 * but (very important) not to do this too often in order to ensure that
1829 * we do not land up introducing fragmentation by changing resource
1830 * groups when not actually required.
1831 *
1832 * The calculation is fairly simple, we want to know whether the SRTTB
1833 * (i.e. smoothed round trip time for blocking operations) to acquire
1834 * the lock for this rgrp's glock is significantly greater than the
1835 * time taken for resource groups on average. We introduce a margin in
1836 * the form of the variable @var which is computed as the sum of the two
1837 * respective variences, and multiplied by a factor depending on @loops
1838 * and whether we have a lot of data to base the decision on. This is
1839 * then tested against the square difference of the means in order to
1840 * decide whether the result is statistically significant or not.
1841 *
1842 * Returns: A boolean verdict on the congestion status
1843 */
1844
1845static bool gfs2_rgrp_congested(const struct gfs2_rgrpd *rgd, int loops)
1846{
1847	const struct gfs2_glock *gl = rgd->rd_gl;
1848	const struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
1849	struct gfs2_lkstats *st;
1850	u64 r_dcount, l_dcount;
1851	u64 l_srttb, a_srttb = 0;
1852	s64 srttb_diff;
1853	u64 sqr_diff;
1854	u64 var;
1855	int cpu, nonzero = 0;
1856
1857	preempt_disable();
1858	for_each_present_cpu(cpu) {
1859		st = &per_cpu_ptr(sdp->sd_lkstats, cpu)->lkstats[LM_TYPE_RGRP];
1860		if (st->stats[GFS2_LKS_SRTTB]) {
1861			a_srttb += st->stats[GFS2_LKS_SRTTB];
1862			nonzero++;
1863		}
1864	}
1865	st = &this_cpu_ptr(sdp->sd_lkstats)->lkstats[LM_TYPE_RGRP];
1866	if (nonzero)
1867		do_div(a_srttb, nonzero);
1868	r_dcount = st->stats[GFS2_LKS_DCOUNT];
1869	var = st->stats[GFS2_LKS_SRTTVARB] +
1870	      gl->gl_stats.stats[GFS2_LKS_SRTTVARB];
1871	preempt_enable();
1872
1873	l_srttb = gl->gl_stats.stats[GFS2_LKS_SRTTB];
1874	l_dcount = gl->gl_stats.stats[GFS2_LKS_DCOUNT];
1875
1876	if ((l_dcount < 1) || (r_dcount < 1) || (a_srttb == 0))
1877		return false;
1878
1879	srttb_diff = a_srttb - l_srttb;
1880	sqr_diff = srttb_diff * srttb_diff;
1881
1882	var *= 2;
1883	if (l_dcount < 8 || r_dcount < 8)
1884		var *= 2;
1885	if (loops == 1)
1886		var *= 2;
1887
1888	return ((srttb_diff < 0) && (sqr_diff > var));
1889}
1890
1891/**
1892 * gfs2_rgrp_used_recently
1893 * @rs: The block reservation with the rgrp to test
1894 * @msecs: The time limit in milliseconds
1895 *
1896 * Returns: True if the rgrp glock has been used within the time limit
1897 */
1898static bool gfs2_rgrp_used_recently(const struct gfs2_blkreserv *rs,
1899				    u64 msecs)
1900{
1901	u64 tdiff;
1902
1903	tdiff = ktime_to_ns(ktime_sub(ktime_get_real(),
1904                            rs->rs_rbm.rgd->rd_gl->gl_dstamp));
1905
1906	return tdiff > (msecs * 1000 * 1000);
1907}
1908
1909static u32 gfs2_orlov_skip(const struct gfs2_inode *ip)
1910{
1911	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1912	u32 skip;
1913
1914	get_random_bytes(&skip, sizeof(skip));
1915	return skip % sdp->sd_rgrps;
1916}
1917
1918static bool gfs2_select_rgrp(struct gfs2_rgrpd **pos, const struct gfs2_rgrpd *begin)
1919{
1920	struct gfs2_rgrpd *rgd = *pos;
1921	struct gfs2_sbd *sdp = rgd->rd_sbd;
1922
1923	rgd = gfs2_rgrpd_get_next(rgd);
1924	if (rgd == NULL)
1925		rgd = gfs2_rgrpd_get_first(sdp);
1926	*pos = rgd;
1927	if (rgd != begin) /* If we didn't wrap */
1928		return true;
1929	return false;
1930}
1931
1932/**
1933 * fast_to_acquire - determine if a resource group will be fast to acquire
 
1934 *
1935 * If this is one of our preferred rgrps, it should be quicker to acquire,
1936 * because we tried to set ourselves up as dlm lock master.
1937 */
1938static inline int fast_to_acquire(struct gfs2_rgrpd *rgd)
1939{
1940	struct gfs2_glock *gl = rgd->rd_gl;
1941
1942	if (gl->gl_state != LM_ST_UNLOCKED && list_empty(&gl->gl_holders) &&
1943	    !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
1944	    !test_bit(GLF_DEMOTE, &gl->gl_flags))
1945		return 1;
1946	if (rgd->rd_flags & GFS2_RDF_PREFERRED)
1947		return 1;
1948	return 0;
1949}
1950
1951/**
1952 * gfs2_inplace_reserve - Reserve space in the filesystem
1953 * @ip: the inode to reserve space for
1954 * @ap: the allocation parameters
1955 *
1956 * We try our best to find an rgrp that has at least ap->target blocks
1957 * available. After a couple of passes (loops == 2), the prospects of finding
1958 * such an rgrp diminish. At this stage, we return the first rgrp that has
1959 * atleast ap->min_target blocks available. Either way, we set ap->allowed to
1960 * the number of blocks available in the chosen rgrp.
1961 *
1962 * Returns: 0 on success,
1963 *          -ENOMEM if a suitable rgrp can't be found
1964 *          errno otherwise
1965 */
1966
1967int gfs2_inplace_reserve(struct gfs2_inode *ip, struct gfs2_alloc_parms *ap)
1968{
1969	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1970	struct gfs2_rgrpd *begin = NULL;
1971	struct gfs2_blkreserv *rs = &ip->i_res;
1972	int error = 0, rg_locked, flags = 0;
 
1973	u64 last_unlinked = NO_BLOCK;
 
1974	int loops = 0;
1975	u32 skip = 0;
 
 
1976
1977	if (sdp->sd_args.ar_rgrplvb)
1978		flags |= GL_SKIP;
1979	if (gfs2_assert_warn(sdp, ap->target))
1980		return -EINVAL;
1981	if (gfs2_rs_active(rs)) {
1982		begin = rs->rs_rbm.rgd;
1983	} else if (ip->i_rgd && rgrp_contains_block(ip->i_rgd, ip->i_goal)) {
1984		rs->rs_rbm.rgd = begin = ip->i_rgd;
 
1985	} else {
1986		check_and_update_goal(ip);
1987		rs->rs_rbm.rgd = begin = gfs2_blk2rgrpd(sdp, ip->i_goal, 1);
1988	}
1989	if (S_ISDIR(ip->i_inode.i_mode) && (ap->aflags & GFS2_AF_ORLOV))
1990		skip = gfs2_orlov_skip(ip);
1991	if (rs->rs_rbm.rgd == NULL)
1992		return -EBADSLT;
1993
1994	while (loops < 3) {
1995		rg_locked = 1;
1996
1997		if (!gfs2_glock_is_locked_by_me(rs->rs_rbm.rgd->rd_gl)) {
1998			rg_locked = 0;
 
 
1999			if (skip && skip--)
2000				goto next_rgrp;
2001			if (!gfs2_rs_active(rs)) {
2002				if (loops == 0 &&
2003				    !fast_to_acquire(rs->rs_rbm.rgd))
2004					goto next_rgrp;
2005				if ((loops < 2) &&
2006				    gfs2_rgrp_used_recently(rs, 1000) &&
2007				    gfs2_rgrp_congested(rs->rs_rbm.rgd, loops))
2008					goto next_rgrp;
2009			}
2010			error = gfs2_glock_nq_init(rs->rs_rbm.rgd->rd_gl,
2011						   LM_ST_EXCLUSIVE, flags,
2012						   &rs->rs_rgd_gh);
2013			if (unlikely(error))
2014				return error;
 
2015			if (!gfs2_rs_active(rs) && (loops < 2) &&
2016			    gfs2_rgrp_congested(rs->rs_rbm.rgd, loops))
2017				goto skip_rgrp;
2018			if (sdp->sd_args.ar_rgrplvb) {
2019				error = update_rgrp_lvb(rs->rs_rbm.rgd);
 
2020				if (unlikely(error)) {
2021					gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
 
2022					return error;
2023				}
2024			}
2025		}
2026
2027		/* Skip unuseable resource groups */
2028		if ((rs->rs_rbm.rgd->rd_flags & (GFS2_RGF_NOALLOC |
2029						 GFS2_RDF_ERROR)) ||
2030		    (loops == 0 && ap->target > rs->rs_rbm.rgd->rd_extfail_pt))
2031			goto skip_rgrp;
2032
2033		if (sdp->sd_args.ar_rgrplvb)
2034			gfs2_rgrp_bh_get(rs->rs_rbm.rgd);
 
 
 
2035
2036		/* Get a reservation if we don't already have one */
2037		if (!gfs2_rs_active(rs))
2038			rg_mblk_search(rs->rs_rbm.rgd, ip, ap);
2039
2040		/* Skip rgrps when we can't get a reservation on first pass */
2041		if (!gfs2_rs_active(rs) && (loops < 1))
2042			goto check_rgrp;
2043
2044		/* If rgrp has enough free space, use it */
2045		if (rs->rs_rbm.rgd->rd_free_clone >= ap->target ||
2046		    (loops == 2 && ap->min_target &&
2047		     rs->rs_rbm.rgd->rd_free_clone >= ap->min_target)) {
2048			ip->i_rgd = rs->rs_rbm.rgd;
2049			ap->allowed = ip->i_rgd->rd_free_clone;
2050			return 0;
 
2051		}
 
 
 
 
 
 
 
2052check_rgrp:
2053		/* Check for unlinked inodes which can be reclaimed */
2054		if (rs->rs_rbm.rgd->rd_flags & GFS2_RDF_CHECK)
2055			try_rgrp_unlink(rs->rs_rbm.rgd, &last_unlinked,
2056					ip->i_no_addr);
2057skip_rgrp:
 
 
2058		/* Drop reservation, if we couldn't use reserved rgrp */
2059		if (gfs2_rs_active(rs))
2060			gfs2_rs_deltree(rs);
2061
2062		/* Unlock rgrp if required */
2063		if (!rg_locked)
2064			gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
2065next_rgrp:
2066		/* Find the next rgrp, and continue looking */
2067		if (gfs2_select_rgrp(&rs->rs_rbm.rgd, begin))
2068			continue;
2069		if (skip)
2070			continue;
2071
2072		/* If we've scanned all the rgrps, but found no free blocks
2073		 * then this checks for some less likely conditions before
2074		 * trying again.
2075		 */
2076		loops++;
2077		/* Check that fs hasn't grown if writing to rindex */
2078		if (ip == GFS2_I(sdp->sd_rindex) && !sdp->sd_rindex_uptodate) {
2079			error = gfs2_ri_update(ip);
2080			if (error)
2081				return error;
2082		}
2083		/* Flushing the log may release space */
2084		if (loops == 2)
2085			gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 
 
 
 
2086	}
2087
2088	return -ENOSPC;
2089}
2090
2091/**
2092 * gfs2_inplace_release - release an inplace reservation
2093 * @ip: the inode the reservation was taken out on
2094 *
2095 * Release a reservation made by gfs2_inplace_reserve().
2096 */
2097
2098void gfs2_inplace_release(struct gfs2_inode *ip)
2099{
2100	struct gfs2_blkreserv *rs = &ip->i_res;
2101
2102	if (rs->rs_rgd_gh.gh_gl)
2103		gfs2_glock_dq_uninit(&rs->rs_rgd_gh);
2104}
2105
2106/**
2107 * gfs2_get_block_type - Check a block in a RG is of given type
2108 * @rgd: the resource group holding the block
2109 * @block: the block number
2110 *
2111 * Returns: The block type (GFS2_BLKST_*)
2112 */
2113
2114static unsigned char gfs2_get_block_type(struct gfs2_rgrpd *rgd, u64 block)
2115{
2116	struct gfs2_rbm rbm = { .rgd = rgd, };
2117	int ret;
2118
2119	ret = gfs2_rbm_from_block(&rbm, block);
2120	WARN_ON_ONCE(ret != 0);
2121
2122	return gfs2_testbit(&rbm);
2123}
2124
2125
2126/**
2127 * gfs2_alloc_extent - allocate an extent from a given bitmap
2128 * @rbm: the resource group information
2129 * @dinode: TRUE if the first block we allocate is for a dinode
2130 * @n: The extent length (value/result)
2131 *
2132 * Add the bitmap buffer to the transaction.
2133 * Set the found bits to @new_state to change block's allocation state.
2134 */
2135static void gfs2_alloc_extent(const struct gfs2_rbm *rbm, bool dinode,
2136			     unsigned int *n)
2137{
2138	struct gfs2_rbm pos = { .rgd = rbm->rgd, };
2139	const unsigned int elen = *n;
2140	u64 block;
2141	int ret;
2142
2143	*n = 1;
2144	block = gfs2_rbm_to_block(rbm);
2145	gfs2_trans_add_meta(rbm->rgd->rd_gl, rbm_bi(rbm)->bi_bh);
2146	gfs2_setbit(rbm, true, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2147	block++;
2148	while (*n < elen) {
2149		ret = gfs2_rbm_from_block(&pos, block);
2150		if (ret || gfs2_testbit(&pos) != GFS2_BLKST_FREE)
2151			break;
2152		gfs2_trans_add_meta(pos.rgd->rd_gl, rbm_bi(&pos)->bi_bh);
2153		gfs2_setbit(&pos, true, GFS2_BLKST_USED);
2154		(*n)++;
2155		block++;
2156	}
2157}
2158
2159/**
2160 * rgblk_free - Change alloc state of given block(s)
2161 * @sdp: the filesystem
 
2162 * @bstart: the start of a run of blocks to free
2163 * @blen: the length of the block run (all must lie within ONE RG!)
2164 * @new_state: GFS2_BLKST_XXX the after-allocation block state
2165 *
2166 * Returns:  Resource group containing the block(s)
2167 */
2168
2169static struct gfs2_rgrpd *rgblk_free(struct gfs2_sbd *sdp, u64 bstart,
2170				     u32 blen, unsigned char new_state)
2171{
2172	struct gfs2_rbm rbm;
2173	struct gfs2_bitmap *bi, *bi_prev = NULL;
2174
2175	rbm.rgd = gfs2_blk2rgrpd(sdp, bstart, 1);
2176	if (!rbm.rgd) {
2177		if (gfs2_consist(sdp))
2178			fs_err(sdp, "block = %llu\n", (unsigned long long)bstart);
2179		return NULL;
2180	}
2181
2182	gfs2_rbm_from_block(&rbm, bstart);
2183	while (blen--) {
2184		bi = rbm_bi(&rbm);
2185		if (bi != bi_prev) {
2186			if (!bi->bi_clone) {
2187				bi->bi_clone = kmalloc(bi->bi_bh->b_size,
2188						      GFP_NOFS | __GFP_NOFAIL);
2189				memcpy(bi->bi_clone + bi->bi_offset,
2190				       bi->bi_bh->b_data + bi->bi_offset,
2191				       bi->bi_len);
2192			}
2193			gfs2_trans_add_meta(rbm.rgd->rd_gl, bi->bi_bh);
2194			bi_prev = bi;
2195		}
2196		gfs2_setbit(&rbm, false, new_state);
2197		gfs2_rbm_incr(&rbm);
2198	}
2199
2200	return rbm.rgd;
2201}
2202
2203/**
2204 * gfs2_rgrp_dump - print out an rgrp
2205 * @seq: The iterator
2206 * @gl: The glock in question
 
2207 *
2208 */
2209
2210void gfs2_rgrp_dump(struct seq_file *seq, const struct gfs2_glock *gl)
 
2211{
2212	struct gfs2_rgrpd *rgd = gl->gl_object;
2213	struct gfs2_blkreserv *trs;
2214	const struct rb_node *n;
2215
2216	if (rgd == NULL)
2217		return;
2218	gfs2_print_dbg(seq, " R: n:%llu f:%02x b:%u/%u i:%u r:%u e:%u\n",
2219		       (unsigned long long)rgd->rd_addr, rgd->rd_flags,
2220		       rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes,
2221		       rgd->rd_reserved, rgd->rd_extfail_pt);
2222	spin_lock(&rgd->rd_rsspin);
 
 
 
 
 
 
 
2223	for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) {
2224		trs = rb_entry(n, struct gfs2_blkreserv, rs_node);
2225		dump_rs(seq, trs);
2226	}
2227	spin_unlock(&rgd->rd_rsspin);
2228}
2229
2230static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd)
2231{
2232	struct gfs2_sbd *sdp = rgd->rd_sbd;
 
 
2233	fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n",
2234		(unsigned long long)rgd->rd_addr);
2235	fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n");
2236	gfs2_rgrp_dump(NULL, rgd->rd_gl);
 
2237	rgd->rd_flags |= GFS2_RDF_ERROR;
2238}
2239
2240/**
2241 * gfs2_adjust_reservation - Adjust (or remove) a reservation after allocation
2242 * @ip: The inode we have just allocated blocks for
2243 * @rbm: The start of the allocated blocks
2244 * @len: The extent length
2245 *
2246 * Adjusts a reservation after an allocation has taken place. If the
2247 * reservation does not match the allocation, or if it is now empty
2248 * then it is removed.
2249 */
2250
2251static void gfs2_adjust_reservation(struct gfs2_inode *ip,
2252				    const struct gfs2_rbm *rbm, unsigned len)
2253{
2254	struct gfs2_blkreserv *rs = &ip->i_res;
2255	struct gfs2_rgrpd *rgd = rbm->rgd;
2256	unsigned rlen;
2257	u64 block;
2258	int ret;
2259
2260	spin_lock(&rgd->rd_rsspin);
 
2261	if (gfs2_rs_active(rs)) {
2262		if (gfs2_rbm_eq(&rs->rs_rbm, rbm)) {
2263			block = gfs2_rbm_to_block(rbm);
2264			ret = gfs2_rbm_from_block(&rs->rs_rbm, block + len);
2265			rlen = min(rs->rs_free, len);
2266			rs->rs_free -= rlen;
2267			rgd->rd_reserved -= rlen;
 
 
 
2268			trace_gfs2_rs(rs, TRACE_RS_CLAIM);
2269			if (rs->rs_free && !ret)
2270				goto out;
 
2271			/* We used up our block reservation, so we should
2272			   reserve more blocks next time. */
2273			atomic_add(RGRP_RSRV_ADDBLKS, &rs->rs_sizehint);
2274		}
2275		__rs_deltree(rs);
2276	}
2277out:
2278	spin_unlock(&rgd->rd_rsspin);
2279}
2280
2281/**
2282 * gfs2_set_alloc_start - Set starting point for block allocation
2283 * @rbm: The rbm which will be set to the required location
2284 * @ip: The gfs2 inode
2285 * @dinode: Flag to say if allocation includes a new inode
2286 *
2287 * This sets the starting point from the reservation if one is active
2288 * otherwise it falls back to guessing a start point based on the
2289 * inode's goal block or the last allocation point in the rgrp.
2290 */
2291
2292static void gfs2_set_alloc_start(struct gfs2_rbm *rbm,
2293				 const struct gfs2_inode *ip, bool dinode)
2294{
2295	u64 goal;
2296
2297	if (gfs2_rs_active(&ip->i_res)) {
2298		*rbm = ip->i_res.rs_rbm;
2299		return;
 
 
 
 
 
 
 
 
2300	}
2301
2302	if (!dinode && rgrp_contains_block(rbm->rgd, ip->i_goal))
2303		goal = ip->i_goal;
2304	else
2305		goal = rbm->rgd->rd_last_alloc + rbm->rgd->rd_data0;
2306
2307	gfs2_rbm_from_block(rbm, goal);
2308}
2309
2310/**
2311 * gfs2_alloc_blocks - Allocate one or more blocks of data and/or a dinode
2312 * @ip: the inode to allocate the block for
2313 * @bn: Used to return the starting block number
2314 * @nblocks: requested number of blocks/extent length (value/result)
2315 * @dinode: 1 if we're allocating a dinode block, else 0
2316 * @generation: the generation number of the inode
2317 *
2318 * Returns: 0 or error
2319 */
2320
2321int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *nblocks,
2322		      bool dinode, u64 *generation)
2323{
2324	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2325	struct buffer_head *dibh;
2326	struct gfs2_rbm rbm = { .rgd = ip->i_rgd, };
2327	unsigned int ndata;
2328	u64 block; /* block, within the file system scope */
2329	int error;
 
2330
2331	gfs2_set_alloc_start(&rbm, ip, dinode);
2332	error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, NULL, ip, false, NULL);
2333
 
 
 
 
 
2334	if (error == -ENOSPC) {
2335		gfs2_set_alloc_start(&rbm, ip, dinode);
2336		error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, NULL, NULL, false,
2337				      NULL);
2338	}
2339
2340	/* Since all blocks are reserved in advance, this shouldn't happen */
2341	if (error) {
2342		fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d fail_pt=%d\n",
2343			(unsigned long long)ip->i_no_addr, error, *nblocks,
2344			test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags),
2345			rbm.rgd->rd_extfail_pt);
2346		goto rgrp_error;
2347	}
2348
2349	gfs2_alloc_extent(&rbm, dinode, nblocks);
2350	block = gfs2_rbm_to_block(&rbm);
2351	rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0;
2352	if (gfs2_rs_active(&ip->i_res))
2353		gfs2_adjust_reservation(ip, &rbm, *nblocks);
2354	ndata = *nblocks;
2355	if (dinode)
2356		ndata--;
2357
2358	if (!dinode) {
2359		ip->i_goal = block + ndata - 1;
2360		error = gfs2_meta_inode_buffer(ip, &dibh);
2361		if (error == 0) {
2362			struct gfs2_dinode *di =
2363				(struct gfs2_dinode *)dibh->b_data;
2364			gfs2_trans_add_meta(ip->i_gl, dibh);
2365			di->di_goal_meta = di->di_goal_data =
2366				cpu_to_be64(ip->i_goal);
2367			brelse(dibh);
2368		}
2369	}
2370	if (rbm.rgd->rd_free < *nblocks) {
2371		pr_warn("nblocks=%u\n", *nblocks);
 
 
 
2372		goto rgrp_error;
2373	}
2374
 
 
 
 
2375	rbm.rgd->rd_free -= *nblocks;
 
2376	if (dinode) {
 
 
2377		rbm.rgd->rd_dinodes++;
2378		*generation = rbm.rgd->rd_igeneration++;
2379		if (*generation == 0)
2380			*generation = rbm.rgd->rd_igeneration++;
 
2381	}
2382
2383	gfs2_trans_add_meta(rbm.rgd->rd_gl, rbm.rgd->rd_bits[0].bi_bh);
2384	gfs2_rgrp_out(rbm.rgd, rbm.rgd->rd_bits[0].bi_bh->b_data);
2385	gfs2_rgrp_ondisk2lvb(rbm.rgd->rd_rgl, rbm.rgd->rd_bits[0].bi_bh->b_data);
2386
2387	gfs2_statfs_change(sdp, 0, -(s64)*nblocks, dinode ? 1 : 0);
2388	if (dinode)
2389		gfs2_trans_add_unrevoke(sdp, block, *nblocks);
2390
2391	gfs2_quota_change(ip, *nblocks, ip->i_inode.i_uid, ip->i_inode.i_gid);
2392
2393	rbm.rgd->rd_free_clone -= *nblocks;
2394	trace_gfs2_block_alloc(ip, rbm.rgd, block, *nblocks,
2395			       dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2396	*bn = block;
2397	return 0;
2398
2399rgrp_error:
 
2400	gfs2_rgrp_error(rbm.rgd);
2401	return -EIO;
2402}
2403
2404/**
2405 * __gfs2_free_blocks - free a contiguous run of block(s)
2406 * @ip: the inode these blocks are being freed from
 
2407 * @bstart: first block of a run of contiguous blocks
2408 * @blen: the length of the block run
2409 * @meta: 1 if the blocks represent metadata
2410 *
2411 */
2412
2413void __gfs2_free_blocks(struct gfs2_inode *ip, u64 bstart, u32 blen, int meta)
 
2414{
2415	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2416	struct gfs2_rgrpd *rgd;
2417
2418	rgd = rgblk_free(sdp, bstart, blen, GFS2_BLKST_FREE);
2419	if (!rgd)
2420		return;
2421	trace_gfs2_block_alloc(ip, rgd, bstart, blen, GFS2_BLKST_FREE);
2422	rgd->rd_free += blen;
2423	rgd->rd_flags &= ~GFS2_RGF_TRIMMED;
2424	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2425	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2426	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2427
2428	/* Directories keep their data in the metadata address space */
2429	if (meta || ip->i_depth)
2430		gfs2_meta_wipe(ip, bstart, blen);
2431}
2432
2433/**
2434 * gfs2_free_meta - free a contiguous run of data block(s)
2435 * @ip: the inode these blocks are being freed from
 
2436 * @bstart: first block of a run of contiguous blocks
2437 * @blen: the length of the block run
2438 *
2439 */
2440
2441void gfs2_free_meta(struct gfs2_inode *ip, u64 bstart, u32 blen)
 
2442{
2443	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2444
2445	__gfs2_free_blocks(ip, bstart, blen, 1);
2446	gfs2_statfs_change(sdp, 0, +blen, 0);
2447	gfs2_quota_change(ip, -(s64)blen, ip->i_inode.i_uid, ip->i_inode.i_gid);
2448}
2449
2450void gfs2_unlink_di(struct inode *inode)
2451{
2452	struct gfs2_inode *ip = GFS2_I(inode);
2453	struct gfs2_sbd *sdp = GFS2_SB(inode);
2454	struct gfs2_rgrpd *rgd;
2455	u64 blkno = ip->i_no_addr;
2456
2457	rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_UNLINKED);
2458	if (!rgd)
2459		return;
 
 
2460	trace_gfs2_block_alloc(ip, rgd, blkno, 1, GFS2_BLKST_UNLINKED);
2461	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2462	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2463	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2464	update_rgrp_lvb_unlinked(rgd, 1);
2465}
2466
2467static void gfs2_free_uninit_di(struct gfs2_rgrpd *rgd, u64 blkno)
2468{
2469	struct gfs2_sbd *sdp = rgd->rd_sbd;
2470	struct gfs2_rgrpd *tmp_rgd;
2471
2472	tmp_rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_FREE);
2473	if (!tmp_rgd)
2474		return;
2475	gfs2_assert_withdraw(sdp, rgd == tmp_rgd);
2476
 
 
2477	if (!rgd->rd_dinodes)
2478		gfs2_consist_rgrpd(rgd);
2479	rgd->rd_dinodes--;
2480	rgd->rd_free++;
2481
2482	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2483	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2484	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2485	update_rgrp_lvb_unlinked(rgd, -1);
2486
2487	gfs2_statfs_change(sdp, 0, +1, -1);
2488}
2489
2490
2491void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip)
2492{
2493	gfs2_free_uninit_di(rgd, ip->i_no_addr);
2494	trace_gfs2_block_alloc(ip, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE);
2495	gfs2_quota_change(ip, -1, ip->i_inode.i_uid, ip->i_inode.i_gid);
2496	gfs2_meta_wipe(ip, ip->i_no_addr, 1);
2497}
2498
2499/**
2500 * gfs2_check_blk_type - Check the type of a block
2501 * @sdp: The superblock
2502 * @no_addr: The block number to check
2503 * @type: The block type we are looking for
2504 *
 
 
 
 
2505 * Returns: 0 if the block type matches the expected type
2506 *          -ESTALE if it doesn't match
2507 *          or -ve errno if something went wrong while checking
2508 */
2509
2510int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
2511{
2512	struct gfs2_rgrpd *rgd;
2513	struct gfs2_holder rgd_gh;
 
2514	int error = -EINVAL;
2515
2516	rgd = gfs2_blk2rgrpd(sdp, no_addr, 1);
2517	if (!rgd)
2518		goto fail;
2519
2520	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
2521	if (error)
2522		goto fail;
2523
2524	if (gfs2_get_block_type(rgd, no_addr) != type)
2525		error = -ESTALE;
 
 
 
 
 
 
 
 
 
 
 
2526
2527	gfs2_glock_dq_uninit(&rgd_gh);
 
2528fail:
2529	return error;
2530}
2531
2532/**
2533 * gfs2_rlist_add - add a RG to a list of RGs
2534 * @ip: the inode
2535 * @rlist: the list of resource groups
2536 * @block: the block
2537 *
2538 * Figure out what RG a block belongs to and add that RG to the list
2539 *
2540 * FIXME: Don't use NOFAIL
2541 *
2542 */
2543
2544void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
2545		    u64 block)
2546{
2547	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2548	struct gfs2_rgrpd *rgd;
2549	struct gfs2_rgrpd **tmp;
2550	unsigned int new_space;
2551	unsigned int x;
2552
2553	if (gfs2_assert_warn(sdp, !rlist->rl_ghs))
2554		return;
2555
2556	if (ip->i_rgd && rgrp_contains_block(ip->i_rgd, block))
2557		rgd = ip->i_rgd;
2558	else
 
 
 
 
 
2559		rgd = gfs2_blk2rgrpd(sdp, block, 1);
 
 
 
 
 
 
2560	if (!rgd) {
2561		fs_err(sdp, "rlist_add: no rgrp for block %llu\n", (unsigned long long)block);
 
2562		return;
2563	}
2564	ip->i_rgd = rgd;
2565
2566	for (x = 0; x < rlist->rl_rgrps; x++)
2567		if (rlist->rl_rgd[x] == rgd)
 
 
2568			return;
 
 
2569
2570	if (rlist->rl_rgrps == rlist->rl_space) {
2571		new_space = rlist->rl_space + 10;
2572
2573		tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *),
2574			      GFP_NOFS | __GFP_NOFAIL);
2575
2576		if (rlist->rl_rgd) {
2577			memcpy(tmp, rlist->rl_rgd,
2578			       rlist->rl_space * sizeof(struct gfs2_rgrpd *));
2579			kfree(rlist->rl_rgd);
2580		}
2581
2582		rlist->rl_space = new_space;
2583		rlist->rl_rgd = tmp;
2584	}
2585
2586	rlist->rl_rgd[rlist->rl_rgrps++] = rgd;
2587}
2588
2589/**
2590 * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate
2591 *      and initialize an array of glock holders for them
2592 * @rlist: the list of resource groups
2593 * @state: the lock state to acquire the RG lock in
 
2594 *
2595 * FIXME: Don't use NOFAIL
2596 *
2597 */
2598
2599void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state)
 
2600{
2601	unsigned int x;
2602
2603	rlist->rl_ghs = kcalloc(rlist->rl_rgrps, sizeof(struct gfs2_holder),
2604				GFP_NOFS | __GFP_NOFAIL);
 
2605	for (x = 0; x < rlist->rl_rgrps; x++)
2606		gfs2_holder_init(rlist->rl_rgd[x]->rd_gl,
2607				state, 0,
2608				&rlist->rl_ghs[x]);
2609}
2610
2611/**
2612 * gfs2_rlist_free - free a resource group list
2613 * @rlist: the list of resource groups
2614 *
2615 */
2616
2617void gfs2_rlist_free(struct gfs2_rgrp_list *rlist)
2618{
2619	unsigned int x;
2620
2621	kfree(rlist->rl_rgd);
2622
2623	if (rlist->rl_ghs) {
2624		for (x = 0; x < rlist->rl_rgrps; x++)
2625			gfs2_holder_uninit(&rlist->rl_ghs[x]);
2626		kfree(rlist->rl_ghs);
2627		rlist->rl_ghs = NULL;
2628	}
2629}
2630
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
 
 
 
 
   5 */
   6
   7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9#include <linux/slab.h>
  10#include <linux/spinlock.h>
  11#include <linux/completion.h>
  12#include <linux/buffer_head.h>
  13#include <linux/fs.h>
  14#include <linux/gfs2_ondisk.h>
  15#include <linux/prefetch.h>
  16#include <linux/blkdev.h>
  17#include <linux/rbtree.h>
  18#include <linux/random.h>
  19
  20#include "gfs2.h"
  21#include "incore.h"
  22#include "glock.h"
  23#include "glops.h"
  24#include "lops.h"
  25#include "meta_io.h"
  26#include "quota.h"
  27#include "rgrp.h"
  28#include "super.h"
  29#include "trans.h"
  30#include "util.h"
  31#include "log.h"
  32#include "inode.h"
  33#include "trace_gfs2.h"
  34#include "dir.h"
  35
  36#define BFITNOENT ((u32)~0)
  37#define NO_BLOCK ((u64)~0)
  38
  39struct gfs2_rbm {
  40	struct gfs2_rgrpd *rgd;
  41	u32 offset;		/* The offset is bitmap relative */
  42	int bii;		/* Bitmap index */
  43};
  44
  45static inline struct gfs2_bitmap *rbm_bi(const struct gfs2_rbm *rbm)
  46{
  47	return rbm->rgd->rd_bits + rbm->bii;
  48}
  49
  50static inline u64 gfs2_rbm_to_block(const struct gfs2_rbm *rbm)
  51{
  52	BUG_ON(rbm->offset >= rbm->rgd->rd_data);
  53	return rbm->rgd->rd_data0 + (rbm_bi(rbm)->bi_start * GFS2_NBBY) +
  54		rbm->offset;
  55}
  56
  57/*
  58 * These routines are used by the resource group routines (rgrp.c)
  59 * to keep track of block allocation.  Each block is represented by two
  60 * bits.  So, each byte represents GFS2_NBBY (i.e. 4) blocks.
  61 *
  62 * 0 = Free
  63 * 1 = Used (not metadata)
  64 * 2 = Unlinked (still in use) inode
  65 * 3 = Used (metadata)
  66 */
  67
  68struct gfs2_extent {
  69	struct gfs2_rbm rbm;
  70	u32 len;
  71};
  72
  73static const char valid_change[16] = {
  74	        /* current */
  75	/* n */ 0, 1, 1, 1,
  76	/* e */ 1, 0, 0, 0,
  77	/* w */ 0, 0, 0, 1,
  78	        1, 0, 0, 0
  79};
  80
  81static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
  82			 struct gfs2_blkreserv *rs, bool nowrap);
 
  83
  84
  85/**
  86 * gfs2_setbit - Set a bit in the bitmaps
  87 * @rbm: The position of the bit to set
  88 * @do_clone: Also set the clone bitmap, if it exists
  89 * @new_state: the new state of the block
  90 *
  91 */
  92
  93static inline void gfs2_setbit(const struct gfs2_rbm *rbm, bool do_clone,
  94			       unsigned char new_state)
  95{
  96	unsigned char *byte1, *byte2, *end, cur_state;
  97	struct gfs2_bitmap *bi = rbm_bi(rbm);
  98	unsigned int buflen = bi->bi_bytes;
  99	const unsigned int bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
 100
 101	byte1 = bi->bi_bh->b_data + bi->bi_offset + (rbm->offset / GFS2_NBBY);
 102	end = bi->bi_bh->b_data + bi->bi_offset + buflen;
 103
 104	BUG_ON(byte1 >= end);
 105
 106	cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
 107
 108	if (unlikely(!valid_change[new_state * 4 + cur_state])) {
 109		struct gfs2_sbd *sdp = rbm->rgd->rd_sbd;
 110
 111		fs_warn(sdp, "buf_blk = 0x%x old_state=%d, new_state=%d\n",
 112			rbm->offset, cur_state, new_state);
 113		fs_warn(sdp, "rgrp=0x%llx bi_start=0x%x biblk: 0x%llx\n",
 114			(unsigned long long)rbm->rgd->rd_addr, bi->bi_start,
 115			(unsigned long long)bi->bi_bh->b_blocknr);
 116		fs_warn(sdp, "bi_offset=0x%x bi_bytes=0x%x block=0x%llx\n",
 117			bi->bi_offset, bi->bi_bytes,
 118			(unsigned long long)gfs2_rbm_to_block(rbm));
 119		dump_stack();
 120		gfs2_consist_rgrpd(rbm->rgd);
 121		return;
 122	}
 123	*byte1 ^= (cur_state ^ new_state) << bit;
 124
 125	if (do_clone && bi->bi_clone) {
 126		byte2 = bi->bi_clone + bi->bi_offset + (rbm->offset / GFS2_NBBY);
 127		cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
 128		*byte2 ^= (cur_state ^ new_state) << bit;
 129	}
 130}
 131
 132/**
 133 * gfs2_testbit - test a bit in the bitmaps
 134 * @rbm: The bit to test
 135 * @use_clone: If true, test the clone bitmap, not the official bitmap.
 136 *
 137 * Some callers like gfs2_unaligned_extlen need to test the clone bitmaps,
 138 * not the "real" bitmaps, to avoid allocating recently freed blocks.
 139 *
 140 * Returns: The two bit block state of the requested bit
 141 */
 142
 143static inline u8 gfs2_testbit(const struct gfs2_rbm *rbm, bool use_clone)
 144{
 145	struct gfs2_bitmap *bi = rbm_bi(rbm);
 146	const u8 *buffer;
 147	const u8 *byte;
 148	unsigned int bit;
 149
 150	if (use_clone && bi->bi_clone)
 151		buffer = bi->bi_clone;
 152	else
 153		buffer = bi->bi_bh->b_data;
 154	buffer += bi->bi_offset;
 155	byte = buffer + (rbm->offset / GFS2_NBBY);
 156	bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
 157
 158	return (*byte >> bit) & GFS2_BIT_MASK;
 159}
 160
 161/**
 162 * gfs2_bit_search - search bitmap for a state
 163 * @ptr: Pointer to bitmap data
 164 * @mask: Mask to use (normally 0x55555.... but adjusted for search start)
 165 * @state: The state we are searching for
 166 *
 167 * We xor the bitmap data with a pattern which is the bitwise opposite
 168 * of what we are looking for. This gives rise to a pattern of ones
 169 * wherever there is a match. Since we have two bits per entry, we
 170 * take this pattern, shift it down by one place and then and it with
 171 * the original. All the even bit positions (0,2,4, etc) then represent
 172 * successful matches, so we mask with 0x55555..... to remove the unwanted
 173 * odd bit positions.
 174 *
 175 * This allows searching of a whole u64 at once (32 blocks) with a
 176 * single test (on 64 bit arches).
 177 */
 178
 179static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state)
 180{
 181	u64 tmp;
 182	static const u64 search[] = {
 183		[0] = 0xffffffffffffffffULL,
 184		[1] = 0xaaaaaaaaaaaaaaaaULL,
 185		[2] = 0x5555555555555555ULL,
 186		[3] = 0x0000000000000000ULL,
 187	};
 188	tmp = le64_to_cpu(*ptr) ^ search[state];
 189	tmp &= (tmp >> 1);
 190	tmp &= mask;
 191	return tmp;
 192}
 193
 194/**
 195 * rs_cmp - multi-block reservation range compare
 196 * @start: start of the new reservation
 197 * @len: number of blocks in the new reservation
 198 * @rs: existing reservation to compare against
 199 *
 200 * returns: 1 if the block range is beyond the reach of the reservation
 201 *         -1 if the block range is before the start of the reservation
 202 *          0 if the block range overlaps with the reservation
 203 */
 204static inline int rs_cmp(u64 start, u32 len, struct gfs2_blkreserv *rs)
 205{
 206	if (start >= rs->rs_start + rs->rs_requested)
 
 
 207		return 1;
 208	if (rs->rs_start >= start + len)
 209		return -1;
 210	return 0;
 211}
 212
 213/**
 214 * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
 215 *       a block in a given allocation state.
 216 * @buf: the buffer that holds the bitmaps
 217 * @len: the length (in bytes) of the buffer
 218 * @goal: start search at this block's bit-pair (within @buffer)
 219 * @state: GFS2_BLKST_XXX the state of the block we're looking for.
 220 *
 221 * Scope of @goal and returned block number is only within this bitmap buffer,
 222 * not entire rgrp or filesystem.  @buffer will be offset from the actual
 223 * beginning of a bitmap block buffer, skipping any header structures, but
 224 * headers are always a multiple of 64 bits long so that the buffer is
 225 * always aligned to a 64 bit boundary.
 226 *
 227 * The size of the buffer is in bytes, but is it assumed that it is
 228 * always ok to read a complete multiple of 64 bits at the end
 229 * of the block in case the end is no aligned to a natural boundary.
 230 *
 231 * Return: the block number (bitmap buffer scope) that was found
 232 */
 233
 234static u32 gfs2_bitfit(const u8 *buf, const unsigned int len,
 235		       u32 goal, u8 state)
 236{
 237	u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1);
 238	const __le64 *ptr = ((__le64 *)buf) + (goal >> 5);
 239	const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64)));
 240	u64 tmp;
 241	u64 mask = 0x5555555555555555ULL;
 242	u32 bit;
 243
 244	/* Mask off bits we don't care about at the start of the search */
 245	mask <<= spoint;
 246	tmp = gfs2_bit_search(ptr, mask, state);
 247	ptr++;
 248	while(tmp == 0 && ptr < end) {
 249		tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state);
 250		ptr++;
 251	}
 252	/* Mask off any bits which are more than len bytes from the start */
 253	if (ptr == end && (len & (sizeof(u64) - 1)))
 254		tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1))));
 255	/* Didn't find anything, so return */
 256	if (tmp == 0)
 257		return BFITNOENT;
 258	ptr--;
 259	bit = __ffs64(tmp);
 260	bit /= 2;	/* two bits per entry in the bitmap */
 261	return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit;
 262}
 263
 264/**
 265 * gfs2_rbm_from_block - Set the rbm based upon rgd and block number
 266 * @rbm: The rbm with rgd already set correctly
 267 * @block: The block number (filesystem relative)
 268 *
 269 * This sets the bi and offset members of an rbm based on a
 270 * resource group and a filesystem relative block number. The
 271 * resource group must be set in the rbm on entry, the bi and
 272 * offset members will be set by this function.
 273 *
 274 * Returns: 0 on success, or an error code
 275 */
 276
 277static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block)
 278{
 279	if (!rgrp_contains_block(rbm->rgd, block))
 
 
 
 
 280		return -E2BIG;
 
 281	rbm->bii = 0;
 282	rbm->offset = block - rbm->rgd->rd_data0;
 283	/* Check if the block is within the first block */
 284	if (rbm->offset < rbm_bi(rbm)->bi_blocks)
 285		return 0;
 286
 287	/* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */
 288	rbm->offset += (sizeof(struct gfs2_rgrp) -
 289			sizeof(struct gfs2_meta_header)) * GFS2_NBBY;
 290	rbm->bii = rbm->offset / rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 291	rbm->offset -= rbm->bii * rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 292	return 0;
 293}
 294
 295/**
 296 * gfs2_rbm_add - add a number of blocks to an rbm
 297 * @rbm: The rbm with rgd already set correctly
 298 * @blocks: The number of blocks to add to rpm
 299 *
 300 * This function takes an existing rbm structure and adds a number of blocks to
 301 * it.
 
 
 
 302 *
 303 * Returns: True if the new rbm would point past the end of the rgrp.
 304 */
 305
 306static bool gfs2_rbm_add(struct gfs2_rbm *rbm, u32 blocks)
 307{
 308	struct gfs2_rgrpd *rgd = rbm->rgd;
 309	struct gfs2_bitmap *bi = rgd->rd_bits + rbm->bii;
 310
 311	if (rbm->offset + blocks < bi->bi_blocks) {
 312		rbm->offset += blocks;
 313		return false;
 314	}
 315	blocks -= bi->bi_blocks - rbm->offset;
 
 316
 317	for(;;) {
 318		bi++;
 319		if (bi == rgd->rd_bits + rgd->rd_length)
 320			return true;
 321		if (blocks < bi->bi_blocks) {
 322			rbm->offset = blocks;
 323			rbm->bii = bi - rgd->rd_bits;
 324			return false;
 325		}
 326		blocks -= bi->bi_blocks;
 327	}
 328}
 329
 330/**
 331 * gfs2_unaligned_extlen - Look for free blocks which are not byte aligned
 332 * @rbm: Position to search (value/result)
 333 * @n_unaligned: Number of unaligned blocks to check
 334 * @len: Decremented for each block found (terminate on zero)
 335 *
 336 * Returns: true if a non-free block is encountered or the end of the resource
 337 *	    group is reached.
 338 */
 339
 340static bool gfs2_unaligned_extlen(struct gfs2_rbm *rbm, u32 n_unaligned, u32 *len)
 341{
 342	u32 n;
 343	u8 res;
 344
 345	for (n = 0; n < n_unaligned; n++) {
 346		res = gfs2_testbit(rbm, true);
 347		if (res != GFS2_BLKST_FREE)
 348			return true;
 349		(*len)--;
 350		if (*len == 0)
 351			return true;
 352		if (gfs2_rbm_add(rbm, 1))
 353			return true;
 354	}
 355
 356	return false;
 357}
 358
 359/**
 360 * gfs2_free_extlen - Return extent length of free blocks
 361 * @rrbm: Starting position
 362 * @len: Max length to check
 363 *
 364 * Starting at the block specified by the rbm, see how many free blocks
 365 * there are, not reading more than len blocks ahead. This can be done
 366 * using memchr_inv when the blocks are byte aligned, but has to be done
 367 * on a block by block basis in case of unaligned blocks. Also this
 368 * function can cope with bitmap boundaries (although it must stop on
 369 * a resource group boundary)
 370 *
 371 * Returns: Number of free blocks in the extent
 372 */
 373
 374static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len)
 375{
 376	struct gfs2_rbm rbm = *rrbm;
 377	u32 n_unaligned = rbm.offset & 3;
 378	u32 size = len;
 379	u32 bytes;
 380	u32 chunk_size;
 381	u8 *ptr, *start, *end;
 382	u64 block;
 383	struct gfs2_bitmap *bi;
 384
 385	if (n_unaligned &&
 386	    gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len))
 387		goto out;
 388
 389	n_unaligned = len & 3;
 390	/* Start is now byte aligned */
 391	while (len > 3) {
 392		bi = rbm_bi(&rbm);
 393		start = bi->bi_bh->b_data;
 394		if (bi->bi_clone)
 395			start = bi->bi_clone;
 
 396		start += bi->bi_offset;
 397		end = start + bi->bi_bytes;
 398		BUG_ON(rbm.offset & 3);
 399		start += (rbm.offset / GFS2_NBBY);
 400		bytes = min_t(u32, len / GFS2_NBBY, (end - start));
 401		ptr = memchr_inv(start, 0, bytes);
 402		chunk_size = ((ptr == NULL) ? bytes : (ptr - start));
 403		chunk_size *= GFS2_NBBY;
 404		BUG_ON(len < chunk_size);
 405		len -= chunk_size;
 406		block = gfs2_rbm_to_block(&rbm);
 407		if (gfs2_rbm_from_block(&rbm, block + chunk_size)) {
 408			n_unaligned = 0;
 409			break;
 410		}
 411		if (ptr) {
 412			n_unaligned = 3;
 413			break;
 414		}
 415		n_unaligned = len & 3;
 416	}
 417
 418	/* Deal with any bits left over at the end */
 419	if (n_unaligned)
 420		gfs2_unaligned_extlen(&rbm, n_unaligned, &len);
 421out:
 422	return size - len;
 423}
 424
 425/**
 426 * gfs2_bitcount - count the number of bits in a certain state
 427 * @rgd: the resource group descriptor
 428 * @buffer: the buffer that holds the bitmaps
 429 * @buflen: the length (in bytes) of the buffer
 430 * @state: the state of the block we're looking for
 431 *
 432 * Returns: The number of bits
 433 */
 434
 435static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer,
 436			 unsigned int buflen, u8 state)
 437{
 438	const u8 *byte = buffer;
 439	const u8 *end = buffer + buflen;
 440	const u8 state1 = state << 2;
 441	const u8 state2 = state << 4;
 442	const u8 state3 = state << 6;
 443	u32 count = 0;
 444
 445	for (; byte < end; byte++) {
 446		if (((*byte) & 0x03) == state)
 447			count++;
 448		if (((*byte) & 0x0C) == state1)
 449			count++;
 450		if (((*byte) & 0x30) == state2)
 451			count++;
 452		if (((*byte) & 0xC0) == state3)
 453			count++;
 454	}
 455
 456	return count;
 457}
 458
 459/**
 460 * gfs2_rgrp_verify - Verify that a resource group is consistent
 461 * @rgd: the rgrp
 462 *
 463 */
 464
 465void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
 466{
 467	struct gfs2_sbd *sdp = rgd->rd_sbd;
 468	struct gfs2_bitmap *bi = NULL;
 469	u32 length = rgd->rd_length;
 470	u32 count[4], tmp;
 471	int buf, x;
 472
 473	memset(count, 0, 4 * sizeof(u32));
 474
 475	/* Count # blocks in each of 4 possible allocation states */
 476	for (buf = 0; buf < length; buf++) {
 477		bi = rgd->rd_bits + buf;
 478		for (x = 0; x < 4; x++)
 479			count[x] += gfs2_bitcount(rgd,
 480						  bi->bi_bh->b_data +
 481						  bi->bi_offset,
 482						  bi->bi_bytes, x);
 483	}
 484
 485	if (count[0] != rgd->rd_free) {
 486		gfs2_lm(sdp, "free data mismatch:  %u != %u\n",
 487			count[0], rgd->rd_free);
 488		gfs2_consist_rgrpd(rgd);
 489		return;
 490	}
 491
 492	tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes;
 493	if (count[1] != tmp) {
 494		gfs2_lm(sdp, "used data mismatch:  %u != %u\n",
 495			count[1], tmp);
 496		gfs2_consist_rgrpd(rgd);
 497		return;
 498	}
 499
 500	if (count[2] + count[3] != rgd->rd_dinodes) {
 501		gfs2_lm(sdp, "used metadata mismatch:  %u != %u\n",
 502			count[2] + count[3], rgd->rd_dinodes);
 503		gfs2_consist_rgrpd(rgd);
 504		return;
 505	}
 506}
 507
 
 
 
 
 
 
 
 508/**
 509 * gfs2_blk2rgrpd - Find resource group for a given data/meta block number
 510 * @sdp: The GFS2 superblock
 511 * @blk: The data block number
 512 * @exact: True if this needs to be an exact match
 513 *
 514 * The @exact argument should be set to true by most callers. The exception
 515 * is when we need to match blocks which are not represented by the rgrp
 516 * bitmap, but which are part of the rgrp (i.e. padding blocks) which are
 517 * there for alignment purposes. Another way of looking at it is that @exact
 518 * matches only valid data/metadata blocks, but with @exact false, it will
 519 * match any block within the extent of the rgrp.
 520 *
 521 * Returns: The resource group, or NULL if not found
 522 */
 523
 524struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact)
 525{
 526	struct rb_node *n, *next;
 527	struct gfs2_rgrpd *cur;
 528
 529	spin_lock(&sdp->sd_rindex_spin);
 530	n = sdp->sd_rindex_tree.rb_node;
 531	while (n) {
 532		cur = rb_entry(n, struct gfs2_rgrpd, rd_node);
 533		next = NULL;
 534		if (blk < cur->rd_addr)
 535			next = n->rb_left;
 536		else if (blk >= cur->rd_data0 + cur->rd_data)
 537			next = n->rb_right;
 538		if (next == NULL) {
 539			spin_unlock(&sdp->sd_rindex_spin);
 540			if (exact) {
 541				if (blk < cur->rd_addr)
 542					return NULL;
 543				if (blk >= cur->rd_data0 + cur->rd_data)
 544					return NULL;
 545			}
 546			return cur;
 547		}
 548		n = next;
 549	}
 550	spin_unlock(&sdp->sd_rindex_spin);
 551
 552	return NULL;
 553}
 554
 555/**
 556 * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
 557 * @sdp: The GFS2 superblock
 558 *
 559 * Returns: The first rgrp in the filesystem
 560 */
 561
 562struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
 563{
 564	const struct rb_node *n;
 565	struct gfs2_rgrpd *rgd;
 566
 567	spin_lock(&sdp->sd_rindex_spin);
 568	n = rb_first(&sdp->sd_rindex_tree);
 569	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 570	spin_unlock(&sdp->sd_rindex_spin);
 571
 572	return rgd;
 573}
 574
 575/**
 576 * gfs2_rgrpd_get_next - get the next RG
 577 * @rgd: the resource group descriptor
 578 *
 579 * Returns: The next rgrp
 580 */
 581
 582struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
 583{
 584	struct gfs2_sbd *sdp = rgd->rd_sbd;
 585	const struct rb_node *n;
 586
 587	spin_lock(&sdp->sd_rindex_spin);
 588	n = rb_next(&rgd->rd_node);
 589	if (n == NULL)
 590		n = rb_first(&sdp->sd_rindex_tree);
 591
 592	if (unlikely(&rgd->rd_node == n)) {
 593		spin_unlock(&sdp->sd_rindex_spin);
 594		return NULL;
 595	}
 596	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 597	spin_unlock(&sdp->sd_rindex_spin);
 598	return rgd;
 599}
 600
 601void check_and_update_goal(struct gfs2_inode *ip)
 602{
 603	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 604	if (!ip->i_goal || gfs2_blk2rgrpd(sdp, ip->i_goal, 1) == NULL)
 605		ip->i_goal = ip->i_no_addr;
 606}
 607
 608void gfs2_free_clones(struct gfs2_rgrpd *rgd)
 609{
 610	int x;
 611
 612	for (x = 0; x < rgd->rd_length; x++) {
 613		struct gfs2_bitmap *bi = rgd->rd_bits + x;
 614		kfree(bi->bi_clone);
 615		bi->bi_clone = NULL;
 616	}
 617}
 618
 619static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs,
 620		    const char *fs_id_buf)
 
 
 
 
 621{
 622	struct gfs2_inode *ip = container_of(rs, struct gfs2_inode, i_res);
 
 623
 624	gfs2_print_dbg(seq, "%s  B: n:%llu s:%llu f:%u\n",
 625		       fs_id_buf,
 626		       (unsigned long long)ip->i_no_addr,
 627		       (unsigned long long)rs->rs_start,
 628		       rs->rs_requested);
 
 629}
 630
 631/**
 632 * __rs_deltree - remove a multi-block reservation from the rgd tree
 633 * @rs: The reservation to remove
 634 *
 635 */
 636static void __rs_deltree(struct gfs2_blkreserv *rs)
 637{
 638	struct gfs2_rgrpd *rgd;
 639
 640	if (!gfs2_rs_active(rs))
 641		return;
 642
 643	rgd = rs->rs_rgd;
 644	trace_gfs2_rs(rs, TRACE_RS_TREEDEL);
 645	rb_erase(&rs->rs_node, &rgd->rd_rstree);
 646	RB_CLEAR_NODE(&rs->rs_node);
 647
 648	if (rs->rs_requested) {
 649		/* return requested blocks to the rgrp */
 650		BUG_ON(rs->rs_rgd->rd_requested < rs->rs_requested);
 651		rs->rs_rgd->rd_requested -= rs->rs_requested;
 652
 
 
 
 653		/* The rgrp extent failure point is likely not to increase;
 654		   it will only do so if the freed blocks are somehow
 655		   contiguous with a span of free blocks that follows. Still,
 656		   it will force the number to be recalculated later. */
 657		rgd->rd_extfail_pt += rs->rs_requested;
 658		rs->rs_requested = 0;
 
 659	}
 660}
 661
 662/**
 663 * gfs2_rs_deltree - remove a multi-block reservation from the rgd tree
 664 * @rs: The reservation to remove
 665 *
 666 */
 667void gfs2_rs_deltree(struct gfs2_blkreserv *rs)
 668{
 669	struct gfs2_rgrpd *rgd;
 670
 671	rgd = rs->rs_rgd;
 672	if (rgd) {
 673		spin_lock(&rgd->rd_rsspin);
 674		__rs_deltree(rs);
 675		BUG_ON(rs->rs_requested);
 676		spin_unlock(&rgd->rd_rsspin);
 677	}
 678}
 679
 680/**
 681 * gfs2_rs_delete - delete a multi-block reservation
 682 * @ip: The inode for this reservation
 
 683 *
 684 */
 685void gfs2_rs_delete(struct gfs2_inode *ip)
 686{
 687	struct inode *inode = &ip->i_inode;
 688
 689	down_write(&ip->i_rw_mutex);
 690	if (atomic_read(&inode->i_writecount) <= 1)
 691		gfs2_rs_deltree(&ip->i_res);
 
 
 692	up_write(&ip->i_rw_mutex);
 
 693}
 694
 695/**
 696 * return_all_reservations - return all reserved blocks back to the rgrp.
 697 * @rgd: the rgrp that needs its space back
 698 *
 699 * We previously reserved a bunch of blocks for allocation. Now we need to
 700 * give them back. This leave the reservation structures in tact, but removes
 701 * all of their corresponding "no-fly zones".
 702 */
 703static void return_all_reservations(struct gfs2_rgrpd *rgd)
 704{
 705	struct rb_node *n;
 706	struct gfs2_blkreserv *rs;
 707
 708	spin_lock(&rgd->rd_rsspin);
 709	while ((n = rb_first(&rgd->rd_rstree))) {
 710		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
 711		__rs_deltree(rs);
 712	}
 713	spin_unlock(&rgd->rd_rsspin);
 714}
 715
 716void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
 717{
 718	struct rb_node *n;
 719	struct gfs2_rgrpd *rgd;
 720	struct gfs2_glock *gl;
 721
 722	while ((n = rb_first(&sdp->sd_rindex_tree))) {
 723		rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 724		gl = rgd->rd_gl;
 725
 726		rb_erase(n, &sdp->sd_rindex_tree);
 727
 728		if (gl) {
 729			if (gl->gl_state != LM_ST_UNLOCKED) {
 730				gfs2_glock_cb(gl, LM_ST_UNLOCKED);
 731				flush_delayed_work(&gl->gl_work);
 732			}
 733			gfs2_rgrp_brelse(rgd);
 734			glock_clear_object(gl, rgd);
 735			gfs2_glock_put(gl);
 736		}
 737
 738		gfs2_free_clones(rgd);
 
 739		return_all_reservations(rgd);
 740		kfree(rgd->rd_bits);
 741		rgd->rd_bits = NULL;
 742		kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 743	}
 744}
 745
 
 
 
 
 
 
 
 
 
 746/**
 747 * compute_bitstructs - Compute the bitmap sizes
 748 * @rgd: The resource group descriptor
 749 *
 750 * Calculates bitmap descriptors, one for each block that contains bitmap data
 751 *
 752 * Returns: errno
 753 */
 754
 755static int compute_bitstructs(struct gfs2_rgrpd *rgd)
 756{
 757	struct gfs2_sbd *sdp = rgd->rd_sbd;
 758	struct gfs2_bitmap *bi;
 759	u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */
 760	u32 bytes_left, bytes;
 761	int x;
 762
 763	if (!length)
 764		return -EINVAL;
 765
 766	rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS);
 767	if (!rgd->rd_bits)
 768		return -ENOMEM;
 769
 770	bytes_left = rgd->rd_bitbytes;
 771
 772	for (x = 0; x < length; x++) {
 773		bi = rgd->rd_bits + x;
 774
 775		bi->bi_flags = 0;
 776		/* small rgrp; bitmap stored completely in header block */
 777		if (length == 1) {
 778			bytes = bytes_left;
 779			bi->bi_offset = sizeof(struct gfs2_rgrp);
 780			bi->bi_start = 0;
 781			bi->bi_bytes = bytes;
 782			bi->bi_blocks = bytes * GFS2_NBBY;
 783		/* header block */
 784		} else if (x == 0) {
 785			bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
 786			bi->bi_offset = sizeof(struct gfs2_rgrp);
 787			bi->bi_start = 0;
 788			bi->bi_bytes = bytes;
 789			bi->bi_blocks = bytes * GFS2_NBBY;
 790		/* last block */
 791		} else if (x + 1 == length) {
 792			bytes = bytes_left;
 793			bi->bi_offset = sizeof(struct gfs2_meta_header);
 794			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 795			bi->bi_bytes = bytes;
 796			bi->bi_blocks = bytes * GFS2_NBBY;
 797		/* other blocks */
 798		} else {
 799			bytes = sdp->sd_sb.sb_bsize -
 800				sizeof(struct gfs2_meta_header);
 801			bi->bi_offset = sizeof(struct gfs2_meta_header);
 802			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 803			bi->bi_bytes = bytes;
 804			bi->bi_blocks = bytes * GFS2_NBBY;
 805		}
 806
 807		bytes_left -= bytes;
 808	}
 809
 810	if (bytes_left) {
 811		gfs2_consist_rgrpd(rgd);
 812		return -EIO;
 813	}
 814	bi = rgd->rd_bits + (length - 1);
 815	if ((bi->bi_start + bi->bi_bytes) * GFS2_NBBY != rgd->rd_data) {
 816		gfs2_lm(sdp,
 817			"ri_addr=%llu "
 818			"ri_length=%u "
 819			"ri_data0=%llu "
 820			"ri_data=%u "
 821			"ri_bitbytes=%u "
 822			"start=%u len=%u offset=%u\n",
 823			(unsigned long long)rgd->rd_addr,
 824			rgd->rd_length,
 825			(unsigned long long)rgd->rd_data0,
 826			rgd->rd_data,
 827			rgd->rd_bitbytes,
 828			bi->bi_start, bi->bi_bytes, bi->bi_offset);
 829		gfs2_consist_rgrpd(rgd);
 830		return -EIO;
 831	}
 832
 833	return 0;
 834}
 835
 836/**
 837 * gfs2_ri_total - Total up the file system space, according to the rindex.
 838 * @sdp: the filesystem
 839 *
 840 */
 841u64 gfs2_ri_total(struct gfs2_sbd *sdp)
 842{
 843	u64 total_data = 0;	
 844	struct inode *inode = sdp->sd_rindex;
 845	struct gfs2_inode *ip = GFS2_I(inode);
 846	char buf[sizeof(struct gfs2_rindex)];
 847	int error, rgrps;
 848
 849	for (rgrps = 0;; rgrps++) {
 850		loff_t pos = rgrps * sizeof(struct gfs2_rindex);
 851
 852		if (pos + sizeof(struct gfs2_rindex) > i_size_read(inode))
 853			break;
 854		error = gfs2_internal_read(ip, buf, &pos,
 855					   sizeof(struct gfs2_rindex));
 856		if (error != sizeof(struct gfs2_rindex))
 857			break;
 858		total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data);
 859	}
 860	return total_data;
 861}
 862
 863static int rgd_insert(struct gfs2_rgrpd *rgd)
 864{
 865	struct gfs2_sbd *sdp = rgd->rd_sbd;
 866	struct rb_node **newn = &sdp->sd_rindex_tree.rb_node, *parent = NULL;
 867
 868	/* Figure out where to put new node */
 869	while (*newn) {
 870		struct gfs2_rgrpd *cur = rb_entry(*newn, struct gfs2_rgrpd,
 871						  rd_node);
 872
 873		parent = *newn;
 874		if (rgd->rd_addr < cur->rd_addr)
 875			newn = &((*newn)->rb_left);
 876		else if (rgd->rd_addr > cur->rd_addr)
 877			newn = &((*newn)->rb_right);
 878		else
 879			return -EEXIST;
 880	}
 881
 882	rb_link_node(&rgd->rd_node, parent, newn);
 883	rb_insert_color(&rgd->rd_node, &sdp->sd_rindex_tree);
 884	sdp->sd_rgrps++;
 885	return 0;
 886}
 887
 888/**
 889 * read_rindex_entry - Pull in a new resource index entry from the disk
 890 * @ip: Pointer to the rindex inode
 891 *
 892 * Returns: 0 on success, > 0 on EOF, error code otherwise
 893 */
 894
 895static int read_rindex_entry(struct gfs2_inode *ip)
 896{
 897	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 
 898	loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
 899	struct gfs2_rindex buf;
 900	int error;
 901	struct gfs2_rgrpd *rgd;
 902
 903	if (pos >= i_size_read(&ip->i_inode))
 904		return 1;
 905
 906	error = gfs2_internal_read(ip, (char *)&buf, &pos,
 907				   sizeof(struct gfs2_rindex));
 908
 909	if (error != sizeof(struct gfs2_rindex))
 910		return (error == 0) ? 1 : error;
 911
 912	rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS);
 913	error = -ENOMEM;
 914	if (!rgd)
 915		return error;
 916
 917	rgd->rd_sbd = sdp;
 918	rgd->rd_addr = be64_to_cpu(buf.ri_addr);
 919	rgd->rd_length = be32_to_cpu(buf.ri_length);
 920	rgd->rd_data0 = be64_to_cpu(buf.ri_data0);
 921	rgd->rd_data = be32_to_cpu(buf.ri_data);
 922	rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes);
 923	spin_lock_init(&rgd->rd_rsspin);
 924	mutex_init(&rgd->rd_mutex);
 
 
 
 925
 926	error = gfs2_glock_get(sdp, rgd->rd_addr,
 927			       &gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
 928	if (error)
 929		goto fail;
 930
 931	error = compute_bitstructs(rgd);
 932	if (error)
 933		goto fail_glock;
 934
 935	rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr;
 936	rgd->rd_flags &= ~GFS2_RDF_PREFERRED;
 937	if (rgd->rd_data > sdp->sd_max_rg_data)
 938		sdp->sd_max_rg_data = rgd->rd_data;
 939	spin_lock(&sdp->sd_rindex_spin);
 940	error = rgd_insert(rgd);
 941	spin_unlock(&sdp->sd_rindex_spin);
 942	if (!error) {
 943		glock_set_object(rgd->rd_gl, rgd);
 944		return 0;
 945	}
 946
 947	error = 0; /* someone else read in the rgrp; free it and ignore it */
 948fail_glock:
 949	gfs2_glock_put(rgd->rd_gl);
 950
 951fail:
 952	kfree(rgd->rd_bits);
 953	rgd->rd_bits = NULL;
 954	kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 955	return error;
 956}
 957
 958/**
 959 * set_rgrp_preferences - Run all the rgrps, selecting some we prefer to use
 960 * @sdp: the GFS2 superblock
 961 *
 962 * The purpose of this function is to select a subset of the resource groups
 963 * and mark them as PREFERRED. We do it in such a way that each node prefers
 964 * to use a unique set of rgrps to minimize glock contention.
 965 */
 966static void set_rgrp_preferences(struct gfs2_sbd *sdp)
 967{
 968	struct gfs2_rgrpd *rgd, *first;
 969	int i;
 970
 971	/* Skip an initial number of rgrps, based on this node's journal ID.
 972	   That should start each node out on its own set. */
 973	rgd = gfs2_rgrpd_get_first(sdp);
 974	for (i = 0; i < sdp->sd_lockstruct.ls_jid; i++)
 975		rgd = gfs2_rgrpd_get_next(rgd);
 976	first = rgd;
 977
 978	do {
 979		rgd->rd_flags |= GFS2_RDF_PREFERRED;
 980		for (i = 0; i < sdp->sd_journals; i++) {
 981			rgd = gfs2_rgrpd_get_next(rgd);
 982			if (!rgd || rgd == first)
 983				break;
 984		}
 985	} while (rgd && rgd != first);
 986}
 987
 988/**
 989 * gfs2_ri_update - Pull in a new resource index from the disk
 990 * @ip: pointer to the rindex inode
 991 *
 992 * Returns: 0 on successful update, error code otherwise
 993 */
 994
 995static int gfs2_ri_update(struct gfs2_inode *ip)
 996{
 997	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 998	int error;
 999
1000	do {
1001		error = read_rindex_entry(ip);
1002	} while (error == 0);
1003
1004	if (error < 0)
1005		return error;
1006
1007	if (RB_EMPTY_ROOT(&sdp->sd_rindex_tree)) {
1008		fs_err(sdp, "no resource groups found in the file system.\n");
1009		return -ENOENT;
1010	}
1011	set_rgrp_preferences(sdp);
1012
1013	sdp->sd_rindex_uptodate = 1;
1014	return 0;
1015}
1016
1017/**
1018 * gfs2_rindex_update - Update the rindex if required
1019 * @sdp: The GFS2 superblock
1020 *
1021 * We grab a lock on the rindex inode to make sure that it doesn't
1022 * change whilst we are performing an operation. We keep this lock
1023 * for quite long periods of time compared to other locks. This
1024 * doesn't matter, since it is shared and it is very, very rarely
1025 * accessed in the exclusive mode (i.e. only when expanding the filesystem).
1026 *
1027 * This makes sure that we're using the latest copy of the resource index
1028 * special file, which might have been updated if someone expanded the
1029 * filesystem (via gfs2_grow utility), which adds new resource groups.
1030 *
1031 * Returns: 0 on succeess, error code otherwise
1032 */
1033
1034int gfs2_rindex_update(struct gfs2_sbd *sdp)
1035{
1036	struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
1037	struct gfs2_glock *gl = ip->i_gl;
1038	struct gfs2_holder ri_gh;
1039	int error = 0;
1040	int unlock_required = 0;
1041
1042	/* Read new copy from disk if we don't have the latest */
1043	if (!sdp->sd_rindex_uptodate) {
1044		if (!gfs2_glock_is_locked_by_me(gl)) {
1045			error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, &ri_gh);
1046			if (error)
1047				return error;
1048			unlock_required = 1;
1049		}
1050		if (!sdp->sd_rindex_uptodate)
1051			error = gfs2_ri_update(ip);
1052		if (unlock_required)
1053			gfs2_glock_dq_uninit(&ri_gh);
1054	}
1055
1056	return error;
1057}
1058
1059static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf)
1060{
1061	const struct gfs2_rgrp *str = buf;
1062	u32 rg_flags;
1063
1064	rg_flags = be32_to_cpu(str->rg_flags);
1065	rg_flags &= ~GFS2_RDF_MASK;
1066	rgd->rd_flags &= GFS2_RDF_MASK;
1067	rgd->rd_flags |= rg_flags;
1068	rgd->rd_free = be32_to_cpu(str->rg_free);
1069	rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes);
1070	rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration);
1071	/* rd_data0, rd_data and rd_bitbytes already set from rindex */
1072}
1073
1074static void gfs2_rgrp_ondisk2lvb(struct gfs2_rgrp_lvb *rgl, const void *buf)
1075{
1076	const struct gfs2_rgrp *str = buf;
1077
1078	rgl->rl_magic = cpu_to_be32(GFS2_MAGIC);
1079	rgl->rl_flags = str->rg_flags;
1080	rgl->rl_free = str->rg_free;
1081	rgl->rl_dinodes = str->rg_dinodes;
1082	rgl->rl_igeneration = str->rg_igeneration;
1083	rgl->__pad = 0UL;
1084}
1085
1086static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf)
1087{
1088	struct gfs2_rgrpd *next = gfs2_rgrpd_get_next(rgd);
1089	struct gfs2_rgrp *str = buf;
1090	u32 crc;
1091
1092	str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK);
1093	str->rg_free = cpu_to_be32(rgd->rd_free);
1094	str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes);
1095	if (next == NULL)
1096		str->rg_skip = 0;
1097	else if (next->rd_addr > rgd->rd_addr)
1098		str->rg_skip = cpu_to_be32(next->rd_addr - rgd->rd_addr);
1099	str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration);
1100	str->rg_data0 = cpu_to_be64(rgd->rd_data0);
1101	str->rg_data = cpu_to_be32(rgd->rd_data);
1102	str->rg_bitbytes = cpu_to_be32(rgd->rd_bitbytes);
1103	str->rg_crc = 0;
1104	crc = gfs2_disk_hash(buf, sizeof(struct gfs2_rgrp));
1105	str->rg_crc = cpu_to_be32(crc);
1106
1107	memset(&str->rg_reserved, 0, sizeof(str->rg_reserved));
1108	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, buf);
1109}
1110
1111static int gfs2_rgrp_lvb_valid(struct gfs2_rgrpd *rgd)
1112{
1113	struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1114	struct gfs2_rgrp *str = (struct gfs2_rgrp *)rgd->rd_bits[0].bi_bh->b_data;
1115	struct gfs2_sbd *sdp = rgd->rd_sbd;
1116	int valid = 1;
1117
1118	if (rgl->rl_flags != str->rg_flags) {
1119		fs_warn(sdp, "GFS2: rgd: %llu lvb flag mismatch %u/%u",
1120			(unsigned long long)rgd->rd_addr,
1121		       be32_to_cpu(rgl->rl_flags), be32_to_cpu(str->rg_flags));
1122		valid = 0;
1123	}
1124	if (rgl->rl_free != str->rg_free) {
1125		fs_warn(sdp, "GFS2: rgd: %llu lvb free mismatch %u/%u",
1126			(unsigned long long)rgd->rd_addr,
1127			be32_to_cpu(rgl->rl_free), be32_to_cpu(str->rg_free));
1128		valid = 0;
1129	}
1130	if (rgl->rl_dinodes != str->rg_dinodes) {
1131		fs_warn(sdp, "GFS2: rgd: %llu lvb dinode mismatch %u/%u",
1132			(unsigned long long)rgd->rd_addr,
1133			be32_to_cpu(rgl->rl_dinodes),
1134			be32_to_cpu(str->rg_dinodes));
1135		valid = 0;
1136	}
1137	if (rgl->rl_igeneration != str->rg_igeneration) {
1138		fs_warn(sdp, "GFS2: rgd: %llu lvb igen mismatch %llu/%llu",
1139			(unsigned long long)rgd->rd_addr,
1140			(unsigned long long)be64_to_cpu(rgl->rl_igeneration),
1141			(unsigned long long)be64_to_cpu(str->rg_igeneration));
1142		valid = 0;
1143	}
1144	return valid;
1145}
1146
1147static u32 count_unlinked(struct gfs2_rgrpd *rgd)
1148{
1149	struct gfs2_bitmap *bi;
1150	const u32 length = rgd->rd_length;
1151	const u8 *buffer = NULL;
1152	u32 i, goal, count = 0;
1153
1154	for (i = 0, bi = rgd->rd_bits; i < length; i++, bi++) {
1155		goal = 0;
1156		buffer = bi->bi_bh->b_data + bi->bi_offset;
1157		WARN_ON(!buffer_uptodate(bi->bi_bh));
1158		while (goal < bi->bi_blocks) {
1159			goal = gfs2_bitfit(buffer, bi->bi_bytes, goal,
1160					   GFS2_BLKST_UNLINKED);
1161			if (goal == BFITNOENT)
1162				break;
1163			count++;
1164			goal++;
1165		}
1166	}
1167
1168	return count;
1169}
1170
1171static void rgrp_set_bitmap_flags(struct gfs2_rgrpd *rgd)
1172{
1173	struct gfs2_bitmap *bi;
1174	int x;
1175
1176	if (rgd->rd_free) {
1177		for (x = 0; x < rgd->rd_length; x++) {
1178			bi = rgd->rd_bits + x;
1179			clear_bit(GBF_FULL, &bi->bi_flags);
1180		}
1181	} else {
1182		for (x = 0; x < rgd->rd_length; x++) {
1183			bi = rgd->rd_bits + x;
1184			set_bit(GBF_FULL, &bi->bi_flags);
1185		}
1186	}
1187}
1188
1189/**
1190 * gfs2_rgrp_go_instantiate - Read in a RG's header and bitmaps
1191 * @gl: the glock representing the rgrpd to read in
1192 *
1193 * Read in all of a Resource Group's header and bitmap blocks.
1194 * Caller must eventually call gfs2_rgrp_brelse() to free the bitmaps.
1195 *
1196 * Returns: errno
1197 */
1198
1199int gfs2_rgrp_go_instantiate(struct gfs2_glock *gl)
1200{
1201	struct gfs2_rgrpd *rgd = gl->gl_object;
1202	struct gfs2_sbd *sdp = rgd->rd_sbd;
 
1203	unsigned int length = rgd->rd_length;
1204	struct gfs2_bitmap *bi;
1205	unsigned int x, y;
1206	int error;
1207
1208	if (rgd->rd_bits[0].bi_bh != NULL)
1209		return 0;
1210
1211	for (x = 0; x < length; x++) {
1212		bi = rgd->rd_bits + x;
1213		error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, 0, &bi->bi_bh);
1214		if (error)
1215			goto fail;
1216	}
1217
1218	for (y = length; y--;) {
1219		bi = rgd->rd_bits + y;
1220		error = gfs2_meta_wait(sdp, bi->bi_bh);
1221		if (error)
1222			goto fail;
1223		if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB :
1224					      GFS2_METATYPE_RG)) {
1225			error = -EIO;
1226			goto fail;
1227		}
1228	}
1229
1230	gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
1231	rgrp_set_bitmap_flags(rgd);
1232	rgd->rd_flags |= GFS2_RDF_CHECK;
1233	rgd->rd_free_clone = rgd->rd_free;
1234	GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved);
1235	/* max out the rgrp allocation failure point */
1236	rgd->rd_extfail_pt = rgd->rd_free;
 
 
1237	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) {
1238		rgd->rd_rgl->rl_unlinked = cpu_to_be32(count_unlinked(rgd));
1239		gfs2_rgrp_ondisk2lvb(rgd->rd_rgl,
1240				     rgd->rd_bits[0].bi_bh->b_data);
1241	} else if (sdp->sd_args.ar_rgrplvb) {
 
1242		if (!gfs2_rgrp_lvb_valid(rgd)){
1243			gfs2_consist_rgrpd(rgd);
1244			error = -EIO;
1245			goto fail;
1246		}
1247		if (rgd->rd_rgl->rl_unlinked == 0)
1248			rgd->rd_flags &= ~GFS2_RDF_CHECK;
1249	}
1250	return 0;
1251
1252fail:
1253	while (x--) {
1254		bi = rgd->rd_bits + x;
1255		brelse(bi->bi_bh);
1256		bi->bi_bh = NULL;
1257		gfs2_assert_warn(sdp, !bi->bi_clone);
1258	}
 
1259	return error;
1260}
1261
1262static int update_rgrp_lvb(struct gfs2_rgrpd *rgd, struct gfs2_holder *gh)
1263{
1264	u32 rl_flags;
1265
1266	if (!test_bit(GLF_INSTANTIATE_NEEDED, &gh->gh_gl->gl_flags))
1267		return 0;
1268
1269	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic)
1270		return gfs2_instantiate(gh);
1271
1272	rl_flags = be32_to_cpu(rgd->rd_rgl->rl_flags);
1273	rl_flags &= ~GFS2_RDF_MASK;
1274	rgd->rd_flags &= GFS2_RDF_MASK;
1275	rgd->rd_flags |= (rl_flags | GFS2_RDF_CHECK);
1276	if (rgd->rd_rgl->rl_unlinked == 0)
1277		rgd->rd_flags &= ~GFS2_RDF_CHECK;
1278	rgd->rd_free = be32_to_cpu(rgd->rd_rgl->rl_free);
1279	rgrp_set_bitmap_flags(rgd);
1280	rgd->rd_free_clone = rgd->rd_free;
1281	GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved);
1282	/* max out the rgrp allocation failure point */
1283	rgd->rd_extfail_pt = rgd->rd_free;
1284	rgd->rd_dinodes = be32_to_cpu(rgd->rd_rgl->rl_dinodes);
1285	rgd->rd_igeneration = be64_to_cpu(rgd->rd_rgl->rl_igeneration);
1286	return 0;
1287}
1288
 
 
 
 
 
 
 
 
 
 
1289/**
1290 * gfs2_rgrp_brelse - Release RG bitmaps read in with gfs2_rgrp_bh_get()
1291 * @rgd: The resource group
1292 *
1293 */
1294
1295void gfs2_rgrp_brelse(struct gfs2_rgrpd *rgd)
1296{
1297	int x, length = rgd->rd_length;
1298
1299	for (x = 0; x < length; x++) {
1300		struct gfs2_bitmap *bi = rgd->rd_bits + x;
1301		if (bi->bi_bh) {
1302			brelse(bi->bi_bh);
1303			bi->bi_bh = NULL;
1304		}
1305	}
1306	set_bit(GLF_INSTANTIATE_NEEDED, &rgd->rd_gl->gl_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1307}
1308
1309int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
1310			     struct buffer_head *bh,
1311			     const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed)
1312{
1313	struct super_block *sb = sdp->sd_vfs;
1314	u64 blk;
1315	sector_t start = 0;
1316	sector_t nr_blks = 0;
1317	int rv = -EIO;
1318	unsigned int x;
1319	u32 trimmed = 0;
1320	u8 diff;
1321
1322	for (x = 0; x < bi->bi_bytes; x++) {
1323		const u8 *clone = bi->bi_clone ? bi->bi_clone : bi->bi_bh->b_data;
1324		clone += bi->bi_offset;
1325		clone += x;
1326		if (bh) {
1327			const u8 *orig = bh->b_data + bi->bi_offset + x;
1328			diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1));
1329		} else {
1330			diff = ~(*clone | (*clone >> 1));
1331		}
1332		diff &= 0x55;
1333		if (diff == 0)
1334			continue;
1335		blk = offset + ((bi->bi_start + x) * GFS2_NBBY);
1336		while(diff) {
1337			if (diff & 1) {
1338				if (nr_blks == 0)
1339					goto start_new_extent;
1340				if ((start + nr_blks) != blk) {
1341					if (nr_blks >= minlen) {
1342						rv = sb_issue_discard(sb,
1343							start, nr_blks,
1344							GFP_NOFS, 0);
1345						if (rv)
1346							goto fail;
1347						trimmed += nr_blks;
1348					}
1349					nr_blks = 0;
1350start_new_extent:
1351					start = blk;
1352				}
1353				nr_blks++;
1354			}
1355			diff >>= 2;
1356			blk++;
1357		}
1358	}
1359	if (nr_blks >= minlen) {
1360		rv = sb_issue_discard(sb, start, nr_blks, GFP_NOFS, 0);
1361		if (rv)
1362			goto fail;
1363		trimmed += nr_blks;
1364	}
1365	if (ptrimmed)
1366		*ptrimmed = trimmed;
1367	return 0;
1368
1369fail:
1370	if (sdp->sd_args.ar_discard)
1371		fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem\n", rv);
1372	sdp->sd_args.ar_discard = 0;
1373	return rv;
1374}
1375
1376/**
1377 * gfs2_fitrim - Generate discard requests for unused bits of the filesystem
1378 * @filp: Any file on the filesystem
1379 * @argp: Pointer to the arguments (also used to pass result)
1380 *
1381 * Returns: 0 on success, otherwise error code
1382 */
1383
1384int gfs2_fitrim(struct file *filp, void __user *argp)
1385{
1386	struct inode *inode = file_inode(filp);
1387	struct gfs2_sbd *sdp = GFS2_SB(inode);
1388	struct block_device *bdev = sdp->sd_vfs->s_bdev;
1389	struct buffer_head *bh;
1390	struct gfs2_rgrpd *rgd;
1391	struct gfs2_rgrpd *rgd_end;
1392	struct gfs2_holder gh;
1393	struct fstrim_range r;
1394	int ret = 0;
1395	u64 amt;
1396	u64 trimmed = 0;
1397	u64 start, end, minlen;
1398	unsigned int x;
1399	unsigned bs_shift = sdp->sd_sb.sb_bsize_shift;
1400
1401	if (!capable(CAP_SYS_ADMIN))
1402		return -EPERM;
1403
1404	if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
1405		return -EROFS;
1406
1407	if (!bdev_max_discard_sectors(bdev))
1408		return -EOPNOTSUPP;
1409
1410	if (copy_from_user(&r, argp, sizeof(r)))
1411		return -EFAULT;
1412
1413	ret = gfs2_rindex_update(sdp);
1414	if (ret)
1415		return ret;
1416
1417	start = r.start >> bs_shift;
1418	end = start + (r.len >> bs_shift);
1419	minlen = max_t(u64, r.minlen, sdp->sd_sb.sb_bsize);
1420	minlen = max_t(u64, minlen, bdev_discard_granularity(bdev)) >> bs_shift;
1421
1422	if (end <= start || minlen > sdp->sd_max_rg_data)
1423		return -EINVAL;
1424
1425	rgd = gfs2_blk2rgrpd(sdp, start, 0);
1426	rgd_end = gfs2_blk2rgrpd(sdp, end, 0);
1427
1428	if ((gfs2_rgrpd_get_first(sdp) == gfs2_rgrpd_get_next(rgd_end))
1429	    && (start > rgd_end->rd_data0 + rgd_end->rd_data))
1430		return -EINVAL; /* start is beyond the end of the fs */
1431
1432	while (1) {
1433
1434		ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1435					 LM_FLAG_NODE_SCOPE, &gh);
1436		if (ret)
1437			goto out;
1438
1439		if (!(rgd->rd_flags & GFS2_RGF_TRIMMED)) {
1440			/* Trim each bitmap in the rgrp */
1441			for (x = 0; x < rgd->rd_length; x++) {
1442				struct gfs2_bitmap *bi = rgd->rd_bits + x;
1443				rgrp_lock_local(rgd);
1444				ret = gfs2_rgrp_send_discards(sdp,
1445						rgd->rd_data0, NULL, bi, minlen,
1446						&amt);
1447				rgrp_unlock_local(rgd);
1448				if (ret) {
1449					gfs2_glock_dq_uninit(&gh);
1450					goto out;
1451				}
1452				trimmed += amt;
1453			}
1454
1455			/* Mark rgrp as having been trimmed */
1456			ret = gfs2_trans_begin(sdp, RES_RG_HDR, 0);
1457			if (ret == 0) {
1458				bh = rgd->rd_bits[0].bi_bh;
1459				rgrp_lock_local(rgd);
1460				rgd->rd_flags |= GFS2_RGF_TRIMMED;
1461				gfs2_trans_add_meta(rgd->rd_gl, bh);
1462				gfs2_rgrp_out(rgd, bh->b_data);
1463				rgrp_unlock_local(rgd);
1464				gfs2_trans_end(sdp);
1465			}
1466		}
1467		gfs2_glock_dq_uninit(&gh);
1468
1469		if (rgd == rgd_end)
1470			break;
1471
1472		rgd = gfs2_rgrpd_get_next(rgd);
1473	}
1474
1475out:
1476	r.len = trimmed << bs_shift;
1477	if (copy_to_user(argp, &r, sizeof(r)))
1478		return -EFAULT;
1479
1480	return ret;
1481}
1482
1483/**
1484 * rs_insert - insert a new multi-block reservation into the rgrp's rb_tree
1485 * @ip: the inode structure
1486 *
1487 */
1488static void rs_insert(struct gfs2_inode *ip)
1489{
1490	struct rb_node **newn, *parent = NULL;
1491	int rc;
1492	struct gfs2_blkreserv *rs = &ip->i_res;
1493	struct gfs2_rgrpd *rgd = rs->rs_rgd;
 
1494
1495	BUG_ON(gfs2_rs_active(rs));
1496
1497	spin_lock(&rgd->rd_rsspin);
1498	newn = &rgd->rd_rstree.rb_node;
1499	while (*newn) {
1500		struct gfs2_blkreserv *cur =
1501			rb_entry(*newn, struct gfs2_blkreserv, rs_node);
1502
1503		parent = *newn;
1504		rc = rs_cmp(rs->rs_start, rs->rs_requested, cur);
1505		if (rc > 0)
1506			newn = &((*newn)->rb_right);
1507		else if (rc < 0)
1508			newn = &((*newn)->rb_left);
1509		else {
1510			spin_unlock(&rgd->rd_rsspin);
1511			WARN_ON(1);
1512			return;
1513		}
1514	}
1515
1516	rb_link_node(&rs->rs_node, parent, newn);
1517	rb_insert_color(&rs->rs_node, &rgd->rd_rstree);
1518
1519	/* Do our rgrp accounting for the reservation */
1520	rgd->rd_requested += rs->rs_requested; /* blocks requested */
1521	spin_unlock(&rgd->rd_rsspin);
1522	trace_gfs2_rs(rs, TRACE_RS_INSERT);
1523}
1524
1525/**
1526 * rgd_free - return the number of free blocks we can allocate
1527 * @rgd: the resource group
1528 * @rs: The reservation to free
1529 *
1530 * This function returns the number of free blocks for an rgrp.
1531 * That's the clone-free blocks (blocks that are free, not including those
1532 * still being used for unlinked files that haven't been deleted.)
1533 *
1534 * It also subtracts any blocks reserved by someone else, but does not
1535 * include free blocks that are still part of our current reservation,
1536 * because obviously we can (and will) allocate them.
1537 */
1538static inline u32 rgd_free(struct gfs2_rgrpd *rgd, struct gfs2_blkreserv *rs)
1539{
1540	u32 tot_reserved, tot_free;
1541
1542	if (WARN_ON_ONCE(rgd->rd_requested < rs->rs_requested))
1543		return 0;
1544	tot_reserved = rgd->rd_requested - rs->rs_requested;
1545
1546	if (rgd->rd_free_clone < tot_reserved)
1547		tot_reserved = 0;
1548
1549	tot_free = rgd->rd_free_clone - tot_reserved;
1550
1551	return tot_free;
1552}
1553
1554/**
1555 * rg_mblk_search - find a group of multiple free blocks to form a reservation
1556 * @rgd: the resource group descriptor
1557 * @ip: pointer to the inode for which we're reserving blocks
1558 * @ap: the allocation parameters
1559 *
1560 */
1561
1562static void rg_mblk_search(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip,
1563			   const struct gfs2_alloc_parms *ap)
1564{
1565	struct gfs2_rbm rbm = { .rgd = rgd, };
1566	u64 goal;
1567	struct gfs2_blkreserv *rs = &ip->i_res;
1568	u32 extlen;
1569	u32 free_blocks, blocks_available;
1570	int ret;
1571	struct inode *inode = &ip->i_inode;
1572
1573	spin_lock(&rgd->rd_rsspin);
1574	free_blocks = rgd_free(rgd, rs);
1575	if (rgd->rd_free_clone < rgd->rd_requested)
1576		free_blocks = 0;
1577	blocks_available = rgd->rd_free_clone - rgd->rd_reserved;
1578	if (rgd == rs->rs_rgd)
1579		blocks_available += rs->rs_reserved;
1580	spin_unlock(&rgd->rd_rsspin);
1581
1582	if (S_ISDIR(inode->i_mode))
1583		extlen = 1;
1584	else {
1585		extlen = max_t(u32, atomic_read(&ip->i_sizehint), ap->target);
1586		extlen = clamp(extlen, (u32)RGRP_RSRV_MINBLKS, free_blocks);
1587	}
1588	if (free_blocks < extlen || blocks_available < extlen)
1589		return;
1590
1591	/* Find bitmap block that contains bits for goal block */
1592	if (rgrp_contains_block(rgd, ip->i_goal))
1593		goal = ip->i_goal;
1594	else
1595		goal = rgd->rd_last_alloc + rgd->rd_data0;
1596
1597	if (WARN_ON(gfs2_rbm_from_block(&rbm, goal)))
1598		return;
1599
1600	ret = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &extlen, &ip->i_res, true);
1601	if (ret == 0) {
1602		rs->rs_start = gfs2_rbm_to_block(&rbm);
1603		rs->rs_requested = extlen;
 
1604		rs_insert(ip);
1605	} else {
1606		if (goal == rgd->rd_last_alloc + rgd->rd_data0)
1607			rgd->rd_last_alloc = 0;
1608	}
1609}
1610
1611/**
1612 * gfs2_next_unreserved_block - Return next block that is not reserved
1613 * @rgd: The resource group
1614 * @block: The starting block
1615 * @length: The required length
1616 * @ignore_rs: Reservation to ignore
1617 *
1618 * If the block does not appear in any reservation, then return the
1619 * block number unchanged. If it does appear in the reservation, then
1620 * keep looking through the tree of reservations in order to find the
1621 * first block number which is not reserved.
1622 */
1623
1624static u64 gfs2_next_unreserved_block(struct gfs2_rgrpd *rgd, u64 block,
1625				      u32 length,
1626				      struct gfs2_blkreserv *ignore_rs)
1627{
1628	struct gfs2_blkreserv *rs;
1629	struct rb_node *n;
1630	int rc;
1631
1632	spin_lock(&rgd->rd_rsspin);
1633	n = rgd->rd_rstree.rb_node;
1634	while (n) {
1635		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1636		rc = rs_cmp(block, length, rs);
1637		if (rc < 0)
1638			n = n->rb_left;
1639		else if (rc > 0)
1640			n = n->rb_right;
1641		else
1642			break;
1643	}
1644
1645	if (n) {
1646		while (rs_cmp(block, length, rs) == 0 && rs != ignore_rs) {
1647			block = rs->rs_start + rs->rs_requested;
1648			n = n->rb_right;
1649			if (n == NULL)
1650				break;
1651			rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1652		}
1653	}
1654
1655	spin_unlock(&rgd->rd_rsspin);
1656	return block;
1657}
1658
1659/**
1660 * gfs2_reservation_check_and_update - Check for reservations during block alloc
1661 * @rbm: The current position in the resource group
1662 * @rs: Our own reservation
1663 * @minext: The minimum extent length
1664 * @maxext: A pointer to the maximum extent structure
1665 *
1666 * This checks the current position in the rgrp to see whether there is
1667 * a reservation covering this block. If not then this function is a
1668 * no-op. If there is, then the position is moved to the end of the
1669 * contiguous reservation(s) so that we are pointing at the first
1670 * non-reserved block.
1671 *
1672 * Returns: 0 if no reservation, 1 if @rbm has changed, otherwise an error
1673 */
1674
1675static int gfs2_reservation_check_and_update(struct gfs2_rbm *rbm,
1676					     struct gfs2_blkreserv *rs,
1677					     u32 minext,
1678					     struct gfs2_extent *maxext)
1679{
1680	u64 block = gfs2_rbm_to_block(rbm);
1681	u32 extlen = 1;
1682	u64 nblock;
 
1683
1684	/*
1685	 * If we have a minimum extent length, then skip over any extent
1686	 * which is less than the min extent length in size.
1687	 */
1688	if (minext > 1) {
1689		extlen = gfs2_free_extlen(rbm, minext);
1690		if (extlen <= maxext->len)
1691			goto fail;
1692	}
1693
1694	/*
1695	 * Check the extent which has been found against the reservations
1696	 * and skip if parts of it are already reserved
1697	 */
1698	nblock = gfs2_next_unreserved_block(rbm->rgd, block, extlen, rs);
1699	if (nblock == block) {
1700		if (!minext || extlen >= minext)
1701			return 0;
1702
1703		if (extlen > maxext->len) {
1704			maxext->len = extlen;
1705			maxext->rbm = *rbm;
1706		}
1707	} else {
1708		u64 len = nblock - block;
1709		if (len >= (u64)1 << 32)
1710			return -E2BIG;
1711		extlen = len;
1712	}
1713fail:
1714	if (gfs2_rbm_add(rbm, extlen))
1715		return -E2BIG;
1716	return 1;
1717}
1718
1719/**
1720 * gfs2_rbm_find - Look for blocks of a particular state
1721 * @rbm: Value/result starting position and final position
1722 * @state: The state which we want to find
1723 * @minext: Pointer to the requested extent length
1724 *          This is updated to be the actual reservation size.
1725 * @rs: Our own reservation (NULL to skip checking for reservations)
1726 * @nowrap: Stop looking at the end of the rgrp, rather than wrapping
1727 *          around until we've reached the starting point.
 
1728 *
1729 * Side effects:
1730 * - If looking for free blocks, we set GBF_FULL on each bitmap which
1731 *   has no free blocks in it.
1732 * - If looking for free blocks, we set rd_extfail_pt on each rgrp which
1733 *   has come up short on a free block search.
1734 *
1735 * Returns: 0 on success, -ENOSPC if there is no block of the requested state
1736 */
1737
1738static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
1739			 struct gfs2_blkreserv *rs, bool nowrap)
 
1740{
1741	bool scan_from_start = rbm->bii == 0 && rbm->offset == 0;
1742	struct buffer_head *bh;
1743	int last_bii;
 
 
 
1744	u32 offset;
1745	u8 *buffer;
1746	bool wrapped = false;
 
1747	int ret;
1748	struct gfs2_bitmap *bi;
1749	struct gfs2_extent maxext = { .rbm.rgd = rbm->rgd, };
1750
1751	/*
1752	 * Determine the last bitmap to search.  If we're not starting at the
1753	 * beginning of a bitmap, we need to search that bitmap twice to scan
1754	 * the entire resource group.
1755	 */
1756	last_bii = rbm->bii - (rbm->offset == 0);
 
1757
1758	while(1) {
1759		bi = rbm_bi(rbm);
1760		if (test_bit(GBF_FULL, &bi->bi_flags) &&
1761		    (state == GFS2_BLKST_FREE))
1762			goto next_bitmap;
1763
1764		bh = bi->bi_bh;
1765		buffer = bh->b_data + bi->bi_offset;
1766		WARN_ON(!buffer_uptodate(bh));
1767		if (state != GFS2_BLKST_UNLINKED && bi->bi_clone)
1768			buffer = bi->bi_clone + bi->bi_offset;
1769		offset = gfs2_bitfit(buffer, bi->bi_bytes, rbm->offset, state);
1770		if (offset == BFITNOENT) {
1771			if (state == GFS2_BLKST_FREE && rbm->offset == 0)
1772				set_bit(GBF_FULL, &bi->bi_flags);
1773			goto next_bitmap;
1774		}
1775		rbm->offset = offset;
1776		if (!rs || !minext)
1777			return 0;
1778
1779		ret = gfs2_reservation_check_and_update(rbm, rs, *minext,
 
 
1780							&maxext);
1781		if (ret == 0)
1782			return 0;
1783		if (ret > 0)
 
1784			goto next_iter;
 
1785		if (ret == -E2BIG) {
1786			rbm->bii = 0;
1787			rbm->offset = 0;
 
1788			goto res_covered_end_of_rgrp;
1789		}
1790		return ret;
1791
 
 
 
 
1792next_bitmap:	/* Find next bitmap in the rgrp */
1793		rbm->offset = 0;
1794		rbm->bii++;
1795		if (rbm->bii == rbm->rgd->rd_length)
1796			rbm->bii = 0;
1797res_covered_end_of_rgrp:
1798		if (rbm->bii == 0) {
1799			if (wrapped)
1800				break;
1801			wrapped = true;
1802			if (nowrap)
1803				break;
1804		}
1805next_iter:
1806		/* Have we scanned the entire resource group? */
1807		if (wrapped && rbm->bii > last_bii)
1808			break;
1809	}
1810
1811	if (state != GFS2_BLKST_FREE)
1812		return -ENOSPC;
1813
1814	/* If the extent was too small, and it's smaller than the smallest
1815	   to have failed before, remember for future reference that it's
1816	   useless to search this rgrp again for this amount or more. */
1817	if (wrapped && (scan_from_start || rbm->bii > last_bii) &&
1818	    *minext < rbm->rgd->rd_extfail_pt)
1819		rbm->rgd->rd_extfail_pt = *minext - 1;
1820
1821	/* If the maximum extent we found is big enough to fulfill the
1822	   minimum requirements, use it anyway. */
1823	if (maxext.len) {
1824		*rbm = maxext.rbm;
1825		*minext = maxext.len;
1826		return 0;
1827	}
1828
1829	return -ENOSPC;
1830}
1831
1832/**
1833 * try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes
1834 * @rgd: The rgrp
1835 * @last_unlinked: block address of the last dinode we unlinked
1836 * @skip: block address we should explicitly not unlink
1837 *
1838 * Returns: 0 if no error
1839 *          The inode, if one has been found, in inode.
1840 */
1841
1842static void try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked, u64 skip)
1843{
1844	u64 block;
1845	struct gfs2_sbd *sdp = rgd->rd_sbd;
1846	struct gfs2_glock *gl;
1847	struct gfs2_inode *ip;
1848	int error;
1849	int found = 0;
1850	struct gfs2_rbm rbm = { .rgd = rgd, .bii = 0, .offset = 0 };
1851
1852	while (1) {
 
1853		error = gfs2_rbm_find(&rbm, GFS2_BLKST_UNLINKED, NULL, NULL,
1854				      true);
 
1855		if (error == -ENOSPC)
1856			break;
1857		if (WARN_ON_ONCE(error))
1858			break;
1859
1860		block = gfs2_rbm_to_block(&rbm);
1861		if (gfs2_rbm_from_block(&rbm, block + 1))
1862			break;
1863		if (*last_unlinked != NO_BLOCK && block <= *last_unlinked)
1864			continue;
1865		if (block == skip)
1866			continue;
1867		*last_unlinked = block;
1868
1869		error = gfs2_glock_get(sdp, block, &gfs2_iopen_glops, CREATE, &gl);
1870		if (error)
1871			continue;
1872
1873		/* If the inode is already in cache, we can ignore it here
1874		 * because the existing inode disposal code will deal with
1875		 * it when all refs have gone away. Accessing gl_object like
1876		 * this is not safe in general. Here it is ok because we do
1877		 * not dereference the pointer, and we only need an approx
1878		 * answer to whether it is NULL or not.
1879		 */
1880		ip = gl->gl_object;
1881
1882		if (ip || !gfs2_queue_verify_delete(gl, false))
1883			gfs2_glock_put(gl);
1884		else
1885			found++;
1886
1887		/* Limit reclaim to sensible number of tasks */
1888		if (found > NR_CPUS)
1889			return;
1890	}
1891
1892	rgd->rd_flags &= ~GFS2_RDF_CHECK;
1893	return;
1894}
1895
1896/**
1897 * gfs2_rgrp_congested - Use stats to figure out whether an rgrp is congested
1898 * @rgd: The rgrp in question
1899 * @loops: An indication of how picky we can be (0=very, 1=less so)
1900 *
1901 * This function uses the recently added glock statistics in order to
1902 * figure out whether a parciular resource group is suffering from
1903 * contention from multiple nodes. This is done purely on the basis
1904 * of timings, since this is the only data we have to work with and
1905 * our aim here is to reject a resource group which is highly contended
1906 * but (very important) not to do this too often in order to ensure that
1907 * we do not land up introducing fragmentation by changing resource
1908 * groups when not actually required.
1909 *
1910 * The calculation is fairly simple, we want to know whether the SRTTB
1911 * (i.e. smoothed round trip time for blocking operations) to acquire
1912 * the lock for this rgrp's glock is significantly greater than the
1913 * time taken for resource groups on average. We introduce a margin in
1914 * the form of the variable @var which is computed as the sum of the two
1915 * respective variences, and multiplied by a factor depending on @loops
1916 * and whether we have a lot of data to base the decision on. This is
1917 * then tested against the square difference of the means in order to
1918 * decide whether the result is statistically significant or not.
1919 *
1920 * Returns: A boolean verdict on the congestion status
1921 */
1922
1923static bool gfs2_rgrp_congested(const struct gfs2_rgrpd *rgd, int loops)
1924{
1925	const struct gfs2_glock *gl = rgd->rd_gl;
1926	const struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
1927	struct gfs2_lkstats *st;
1928	u64 r_dcount, l_dcount;
1929	u64 l_srttb, a_srttb = 0;
1930	s64 srttb_diff;
1931	u64 sqr_diff;
1932	u64 var;
1933	int cpu, nonzero = 0;
1934
1935	preempt_disable();
1936	for_each_present_cpu(cpu) {
1937		st = &per_cpu_ptr(sdp->sd_lkstats, cpu)->lkstats[LM_TYPE_RGRP];
1938		if (st->stats[GFS2_LKS_SRTTB]) {
1939			a_srttb += st->stats[GFS2_LKS_SRTTB];
1940			nonzero++;
1941		}
1942	}
1943	st = &this_cpu_ptr(sdp->sd_lkstats)->lkstats[LM_TYPE_RGRP];
1944	if (nonzero)
1945		do_div(a_srttb, nonzero);
1946	r_dcount = st->stats[GFS2_LKS_DCOUNT];
1947	var = st->stats[GFS2_LKS_SRTTVARB] +
1948	      gl->gl_stats.stats[GFS2_LKS_SRTTVARB];
1949	preempt_enable();
1950
1951	l_srttb = gl->gl_stats.stats[GFS2_LKS_SRTTB];
1952	l_dcount = gl->gl_stats.stats[GFS2_LKS_DCOUNT];
1953
1954	if ((l_dcount < 1) || (r_dcount < 1) || (a_srttb == 0))
1955		return false;
1956
1957	srttb_diff = a_srttb - l_srttb;
1958	sqr_diff = srttb_diff * srttb_diff;
1959
1960	var *= 2;
1961	if (l_dcount < 8 || r_dcount < 8)
1962		var *= 2;
1963	if (loops == 1)
1964		var *= 2;
1965
1966	return ((srttb_diff < 0) && (sqr_diff > var));
1967}
1968
1969/**
1970 * gfs2_rgrp_used_recently - test if an rgrp has been used recently
1971 * @rs: The block reservation with the rgrp to test
1972 * @msecs: The time limit in milliseconds
1973 *
1974 * Returns: True if the rgrp glock has been used within the time limit
1975 */
1976static bool gfs2_rgrp_used_recently(const struct gfs2_blkreserv *rs,
1977				    u64 msecs)
1978{
1979	u64 tdiff;
1980
1981	tdiff = ktime_to_ns(ktime_sub(ktime_get_real(),
1982                            rs->rs_rgd->rd_gl->gl_dstamp));
1983
1984	return tdiff > (msecs * 1000 * 1000);
1985}
1986
1987static u32 gfs2_orlov_skip(const struct gfs2_inode *ip)
1988{
1989	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 
1990
1991	return get_random_u32() % sdp->sd_rgrps;
 
1992}
1993
1994static bool gfs2_select_rgrp(struct gfs2_rgrpd **pos, const struct gfs2_rgrpd *begin)
1995{
1996	struct gfs2_rgrpd *rgd = *pos;
1997	struct gfs2_sbd *sdp = rgd->rd_sbd;
1998
1999	rgd = gfs2_rgrpd_get_next(rgd);
2000	if (rgd == NULL)
2001		rgd = gfs2_rgrpd_get_first(sdp);
2002	*pos = rgd;
2003	if (rgd != begin) /* If we didn't wrap */
2004		return true;
2005	return false;
2006}
2007
2008/**
2009 * fast_to_acquire - determine if a resource group will be fast to acquire
2010 * @rgd: The rgrp
2011 *
2012 * If this is one of our preferred rgrps, it should be quicker to acquire,
2013 * because we tried to set ourselves up as dlm lock master.
2014 */
2015static inline int fast_to_acquire(struct gfs2_rgrpd *rgd)
2016{
2017	struct gfs2_glock *gl = rgd->rd_gl;
2018
2019	if (gl->gl_state != LM_ST_UNLOCKED && list_empty(&gl->gl_holders) &&
2020	    !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
2021	    !test_bit(GLF_DEMOTE, &gl->gl_flags))
2022		return 1;
2023	if (rgd->rd_flags & GFS2_RDF_PREFERRED)
2024		return 1;
2025	return 0;
2026}
2027
2028/**
2029 * gfs2_inplace_reserve - Reserve space in the filesystem
2030 * @ip: the inode to reserve space for
2031 * @ap: the allocation parameters
2032 *
2033 * We try our best to find an rgrp that has at least ap->target blocks
2034 * available. After a couple of passes (loops == 2), the prospects of finding
2035 * such an rgrp diminish. At this stage, we return the first rgrp that has
2036 * at least ap->min_target blocks available.
 
2037 *
2038 * Returns: 0 on success,
2039 *          -ENOMEM if a suitable rgrp can't be found
2040 *          errno otherwise
2041 */
2042
2043int gfs2_inplace_reserve(struct gfs2_inode *ip, struct gfs2_alloc_parms *ap)
2044{
2045	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2046	struct gfs2_rgrpd *begin = NULL;
2047	struct gfs2_blkreserv *rs = &ip->i_res;
2048	int error = 0, flags = LM_FLAG_NODE_SCOPE;
2049	bool rg_locked;
2050	u64 last_unlinked = NO_BLOCK;
2051	u32 target = ap->target;
2052	int loops = 0;
2053	u32 free_blocks, blocks_available, skip = 0;
2054
2055	BUG_ON(rs->rs_reserved);
2056
2057	if (sdp->sd_args.ar_rgrplvb)
2058		flags |= GL_SKIP;
2059	if (gfs2_assert_warn(sdp, target))
2060		return -EINVAL;
2061	if (gfs2_rs_active(rs)) {
2062		begin = rs->rs_rgd;
2063	} else if (rs->rs_rgd &&
2064		   rgrp_contains_block(rs->rs_rgd, ip->i_goal)) {
2065		begin = rs->rs_rgd;
2066	} else {
2067		check_and_update_goal(ip);
2068		rs->rs_rgd = begin = gfs2_blk2rgrpd(sdp, ip->i_goal, 1);
2069	}
2070	if (S_ISDIR(ip->i_inode.i_mode) && (ap->aflags & GFS2_AF_ORLOV))
2071		skip = gfs2_orlov_skip(ip);
2072	if (rs->rs_rgd == NULL)
2073		return -EBADSLT;
2074
2075	while (loops < 3) {
2076		struct gfs2_rgrpd *rgd;
2077
2078		rg_locked = gfs2_glock_is_locked_by_me(rs->rs_rgd->rd_gl);
2079		if (rg_locked) {
2080			rgrp_lock_local(rs->rs_rgd);
2081		} else {
2082			if (skip && skip--)
2083				goto next_rgrp;
2084			if (!gfs2_rs_active(rs)) {
2085				if (loops == 0 &&
2086				    !fast_to_acquire(rs->rs_rgd))
2087					goto next_rgrp;
2088				if ((loops < 2) &&
2089				    gfs2_rgrp_used_recently(rs, 1000) &&
2090				    gfs2_rgrp_congested(rs->rs_rgd, loops))
2091					goto next_rgrp;
2092			}
2093			error = gfs2_glock_nq_init(rs->rs_rgd->rd_gl,
2094						   LM_ST_EXCLUSIVE, flags,
2095						   &ip->i_rgd_gh);
2096			if (unlikely(error))
2097				return error;
2098			rgrp_lock_local(rs->rs_rgd);
2099			if (!gfs2_rs_active(rs) && (loops < 2) &&
2100			    gfs2_rgrp_congested(rs->rs_rgd, loops))
2101				goto skip_rgrp;
2102			if (sdp->sd_args.ar_rgrplvb) {
2103				error = update_rgrp_lvb(rs->rs_rgd,
2104							&ip->i_rgd_gh);
2105				if (unlikely(error)) {
2106					rgrp_unlock_local(rs->rs_rgd);
2107					gfs2_glock_dq_uninit(&ip->i_rgd_gh);
2108					return error;
2109				}
2110			}
2111		}
2112
2113		/* Skip unusable resource groups */
2114		if ((rs->rs_rgd->rd_flags & (GFS2_RGF_NOALLOC |
2115						 GFS2_RDF_ERROR)) ||
2116		    (loops == 0 && target > rs->rs_rgd->rd_extfail_pt))
2117			goto skip_rgrp;
2118
2119		if (sdp->sd_args.ar_rgrplvb) {
2120			error = gfs2_instantiate(&ip->i_rgd_gh);
2121			if (error)
2122				goto skip_rgrp;
2123		}
2124
2125		/* Get a reservation if we don't already have one */
2126		if (!gfs2_rs_active(rs))
2127			rg_mblk_search(rs->rs_rgd, ip, ap);
2128
2129		/* Skip rgrps when we can't get a reservation on first pass */
2130		if (!gfs2_rs_active(rs) && (loops < 1))
2131			goto check_rgrp;
2132
2133		/* If rgrp has enough free space, use it */
2134		rgd = rs->rs_rgd;
2135		spin_lock(&rgd->rd_rsspin);
2136		free_blocks = rgd_free(rgd, rs);
2137		blocks_available = rgd->rd_free_clone - rgd->rd_reserved;
2138		if (free_blocks < target || blocks_available < target) {
2139			spin_unlock(&rgd->rd_rsspin);
2140			goto check_rgrp;
2141		}
2142		rs->rs_reserved = ap->target;
2143		if (rs->rs_reserved > blocks_available)
2144			rs->rs_reserved = blocks_available;
2145		rgd->rd_reserved += rs->rs_reserved;
2146		spin_unlock(&rgd->rd_rsspin);
2147		rgrp_unlock_local(rs->rs_rgd);
2148		return 0;
2149check_rgrp:
2150		/* Check for unlinked inodes which can be reclaimed */
2151		if (rs->rs_rgd->rd_flags & GFS2_RDF_CHECK)
2152			try_rgrp_unlink(rs->rs_rgd, &last_unlinked,
2153					ip->i_no_addr);
2154skip_rgrp:
2155		rgrp_unlock_local(rs->rs_rgd);
2156
2157		/* Drop reservation, if we couldn't use reserved rgrp */
2158		if (gfs2_rs_active(rs))
2159			gfs2_rs_deltree(rs);
2160
2161		/* Unlock rgrp if required */
2162		if (!rg_locked)
2163			gfs2_glock_dq_uninit(&ip->i_rgd_gh);
2164next_rgrp:
2165		/* Find the next rgrp, and continue looking */
2166		if (gfs2_select_rgrp(&rs->rs_rgd, begin))
2167			continue;
2168		if (skip)
2169			continue;
2170
2171		/* If we've scanned all the rgrps, but found no free blocks
2172		 * then this checks for some less likely conditions before
2173		 * trying again.
2174		 */
2175		loops++;
2176		/* Check that fs hasn't grown if writing to rindex */
2177		if (ip == GFS2_I(sdp->sd_rindex) && !sdp->sd_rindex_uptodate) {
2178			error = gfs2_ri_update(ip);
2179			if (error)
2180				return error;
2181		}
2182		/* Flushing the log may release space */
2183		if (loops == 2) {
2184			if (ap->min_target)
2185				target = ap->min_target;
2186			gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
2187				       GFS2_LFC_INPLACE_RESERVE);
2188		}
2189	}
2190
2191	return -ENOSPC;
2192}
2193
2194/**
2195 * gfs2_inplace_release - release an inplace reservation
2196 * @ip: the inode the reservation was taken out on
2197 *
2198 * Release a reservation made by gfs2_inplace_reserve().
2199 */
2200
2201void gfs2_inplace_release(struct gfs2_inode *ip)
2202{
2203	struct gfs2_blkreserv *rs = &ip->i_res;
2204
2205	if (rs->rs_reserved) {
2206		struct gfs2_rgrpd *rgd = rs->rs_rgd;
 
 
 
 
 
 
 
 
 
2207
2208		spin_lock(&rgd->rd_rsspin);
2209		GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved < rs->rs_reserved);
2210		rgd->rd_reserved -= rs->rs_reserved;
2211		spin_unlock(&rgd->rd_rsspin);
2212		rs->rs_reserved = 0;
2213	}
2214	if (gfs2_holder_initialized(&ip->i_rgd_gh))
2215		gfs2_glock_dq_uninit(&ip->i_rgd_gh);
 
2216}
2217
 
2218/**
2219 * gfs2_alloc_extent - allocate an extent from a given bitmap
2220 * @rbm: the resource group information
2221 * @dinode: TRUE if the first block we allocate is for a dinode
2222 * @n: The extent length (value/result)
2223 *
2224 * Add the bitmap buffer to the transaction.
2225 * Set the found bits to @new_state to change block's allocation state.
2226 */
2227static void gfs2_alloc_extent(const struct gfs2_rbm *rbm, bool dinode,
2228			     unsigned int *n)
2229{
2230	struct gfs2_rbm pos = { .rgd = rbm->rgd, };
2231	const unsigned int elen = *n;
2232	u64 block;
2233	int ret;
2234
2235	*n = 1;
2236	block = gfs2_rbm_to_block(rbm);
2237	gfs2_trans_add_meta(rbm->rgd->rd_gl, rbm_bi(rbm)->bi_bh);
2238	gfs2_setbit(rbm, true, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2239	block++;
2240	while (*n < elen) {
2241		ret = gfs2_rbm_from_block(&pos, block);
2242		if (ret || gfs2_testbit(&pos, true) != GFS2_BLKST_FREE)
2243			break;
2244		gfs2_trans_add_meta(pos.rgd->rd_gl, rbm_bi(&pos)->bi_bh);
2245		gfs2_setbit(&pos, true, GFS2_BLKST_USED);
2246		(*n)++;
2247		block++;
2248	}
2249}
2250
2251/**
2252 * rgblk_free - Change alloc state of given block(s)
2253 * @sdp: the filesystem
2254 * @rgd: the resource group the blocks are in
2255 * @bstart: the start of a run of blocks to free
2256 * @blen: the length of the block run (all must lie within ONE RG!)
2257 * @new_state: GFS2_BLKST_XXX the after-allocation block state
 
 
2258 */
2259
2260static void rgblk_free(struct gfs2_sbd *sdp, struct gfs2_rgrpd *rgd,
2261		       u64 bstart, u32 blen, unsigned char new_state)
2262{
2263	struct gfs2_rbm rbm;
2264	struct gfs2_bitmap *bi, *bi_prev = NULL;
2265
2266	rbm.rgd = rgd;
2267	if (WARN_ON_ONCE(gfs2_rbm_from_block(&rbm, bstart)))
2268		return;
 
 
 
 
 
2269	while (blen--) {
2270		bi = rbm_bi(&rbm);
2271		if (bi != bi_prev) {
2272			if (!bi->bi_clone) {
2273				bi->bi_clone = kmalloc(bi->bi_bh->b_size,
2274						      GFP_NOFS | __GFP_NOFAIL);
2275				memcpy(bi->bi_clone + bi->bi_offset,
2276				       bi->bi_bh->b_data + bi->bi_offset,
2277				       bi->bi_bytes);
2278			}
2279			gfs2_trans_add_meta(rbm.rgd->rd_gl, bi->bi_bh);
2280			bi_prev = bi;
2281		}
2282		gfs2_setbit(&rbm, false, new_state);
2283		gfs2_rbm_add(&rbm, 1);
2284	}
 
 
2285}
2286
2287/**
2288 * gfs2_rgrp_dump - print out an rgrp
2289 * @seq: The iterator
2290 * @rgd: The rgrp in question
2291 * @fs_id_buf: pointer to file system id (if requested)
2292 *
2293 */
2294
2295void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_rgrpd *rgd,
2296		    const char *fs_id_buf)
2297{
 
2298	struct gfs2_blkreserv *trs;
2299	const struct rb_node *n;
2300
2301	spin_lock(&rgd->rd_rsspin);
2302	gfs2_print_dbg(seq, "%s R: n:%llu f:%02x b:%u/%u i:%u q:%u r:%u e:%u\n",
2303		       fs_id_buf,
2304		       (unsigned long long)rgd->rd_addr, rgd->rd_flags,
2305		       rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes,
2306		       rgd->rd_requested, rgd->rd_reserved, rgd->rd_extfail_pt);
2307	if (rgd->rd_sbd->sd_args.ar_rgrplvb && rgd->rd_rgl) {
2308		struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
2309
2310		gfs2_print_dbg(seq, "%s  L: f:%02x b:%u i:%u\n", fs_id_buf,
2311			       be32_to_cpu(rgl->rl_flags),
2312			       be32_to_cpu(rgl->rl_free),
2313			       be32_to_cpu(rgl->rl_dinodes));
2314	}
2315	for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) {
2316		trs = rb_entry(n, struct gfs2_blkreserv, rs_node);
2317		dump_rs(seq, trs, fs_id_buf);
2318	}
2319	spin_unlock(&rgd->rd_rsspin);
2320}
2321
2322static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd)
2323{
2324	struct gfs2_sbd *sdp = rgd->rd_sbd;
2325	char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
2326
2327	fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n",
2328		(unsigned long long)rgd->rd_addr);
2329	fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n");
2330	sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
2331	gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
2332	rgd->rd_flags |= GFS2_RDF_ERROR;
2333}
2334
2335/**
2336 * gfs2_adjust_reservation - Adjust (or remove) a reservation after allocation
2337 * @ip: The inode we have just allocated blocks for
2338 * @rbm: The start of the allocated blocks
2339 * @len: The extent length
2340 *
2341 * Adjusts a reservation after an allocation has taken place. If the
2342 * reservation does not match the allocation, or if it is now empty
2343 * then it is removed.
2344 */
2345
2346static void gfs2_adjust_reservation(struct gfs2_inode *ip,
2347				    const struct gfs2_rbm *rbm, unsigned len)
2348{
2349	struct gfs2_blkreserv *rs = &ip->i_res;
2350	struct gfs2_rgrpd *rgd = rbm->rgd;
 
 
 
2351
2352	BUG_ON(rs->rs_reserved < len);
2353	rs->rs_reserved -= len;
2354	if (gfs2_rs_active(rs)) {
2355		u64 start = gfs2_rbm_to_block(rbm);
2356
2357		if (rs->rs_start == start) {
2358			unsigned int rlen;
2359
2360			rs->rs_start += len;
2361			rlen = min(rs->rs_requested, len);
2362			rs->rs_requested -= rlen;
2363			rgd->rd_requested -= rlen;
2364			trace_gfs2_rs(rs, TRACE_RS_CLAIM);
2365			if (rs->rs_start < rgd->rd_data0 + rgd->rd_data &&
2366			    rs->rs_requested)
2367				return;
2368			/* We used up our block reservation, so we should
2369			   reserve more blocks next time. */
2370			atomic_add(RGRP_RSRV_ADDBLKS, &ip->i_sizehint);
2371		}
2372		__rs_deltree(rs);
2373	}
 
 
2374}
2375
2376/**
2377 * gfs2_set_alloc_start - Set starting point for block allocation
2378 * @rbm: The rbm which will be set to the required location
2379 * @ip: The gfs2 inode
2380 * @dinode: Flag to say if allocation includes a new inode
2381 *
2382 * This sets the starting point from the reservation if one is active
2383 * otherwise it falls back to guessing a start point based on the
2384 * inode's goal block or the last allocation point in the rgrp.
2385 */
2386
2387static void gfs2_set_alloc_start(struct gfs2_rbm *rbm,
2388				 const struct gfs2_inode *ip, bool dinode)
2389{
2390	u64 goal;
2391
2392	if (gfs2_rs_active(&ip->i_res)) {
2393		goal = ip->i_res.rs_start;
2394	} else {
2395		if (!dinode && rgrp_contains_block(rbm->rgd, ip->i_goal))
2396			goal = ip->i_goal;
2397		else
2398			goal = rbm->rgd->rd_last_alloc + rbm->rgd->rd_data0;
2399	}
2400	if (WARN_ON_ONCE(gfs2_rbm_from_block(rbm, goal))) {
2401		rbm->bii = 0;
2402		rbm->offset = 0;
2403	}
 
 
 
 
 
 
 
2404}
2405
2406/**
2407 * gfs2_alloc_blocks - Allocate one or more blocks of data and/or a dinode
2408 * @ip: the inode to allocate the block for
2409 * @bn: Used to return the starting block number
2410 * @nblocks: requested number of blocks/extent length (value/result)
2411 * @dinode: 1 if we're allocating a dinode block, else 0
 
2412 *
2413 * Returns: 0 or error
2414 */
2415
2416int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *nblocks,
2417		      bool dinode)
2418{
2419	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2420	struct buffer_head *dibh;
2421	struct gfs2_rbm rbm = { .rgd = ip->i_res.rs_rgd, };
 
2422	u64 block; /* block, within the file system scope */
2423	u32 minext = 1;
2424	int error = -ENOSPC;
2425
2426	BUG_ON(ip->i_res.rs_reserved < *nblocks);
 
2427
2428	rgrp_lock_local(rbm.rgd);
2429	if (gfs2_rs_active(&ip->i_res)) {
2430		gfs2_set_alloc_start(&rbm, ip, dinode);
2431		error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, &ip->i_res, false);
2432	}
2433	if (error == -ENOSPC) {
2434		gfs2_set_alloc_start(&rbm, ip, dinode);
2435		error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, NULL, false);
 
2436	}
2437
2438	/* Since all blocks are reserved in advance, this shouldn't happen */
2439	if (error) {
2440		fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d fail_pt=%d\n",
2441			(unsigned long long)ip->i_no_addr, error, *nblocks,
2442			test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags),
2443			rbm.rgd->rd_extfail_pt);
2444		goto rgrp_error;
2445	}
2446
2447	gfs2_alloc_extent(&rbm, dinode, nblocks);
2448	block = gfs2_rbm_to_block(&rbm);
2449	rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0;
 
 
 
 
 
 
2450	if (!dinode) {
2451		ip->i_goal = block + *nblocks - 1;
2452		error = gfs2_meta_inode_buffer(ip, &dibh);
2453		if (error == 0) {
2454			struct gfs2_dinode *di =
2455				(struct gfs2_dinode *)dibh->b_data;
2456			gfs2_trans_add_meta(ip->i_gl, dibh);
2457			di->di_goal_meta = di->di_goal_data =
2458				cpu_to_be64(ip->i_goal);
2459			brelse(dibh);
2460		}
2461	}
2462	spin_lock(&rbm.rgd->rd_rsspin);
2463	gfs2_adjust_reservation(ip, &rbm, *nblocks);
2464	if (rbm.rgd->rd_free < *nblocks || rbm.rgd->rd_reserved < *nblocks) {
2465		fs_warn(sdp, "nblocks=%u\n", *nblocks);
2466		spin_unlock(&rbm.rgd->rd_rsspin);
2467		goto rgrp_error;
2468	}
2469	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_reserved < *nblocks);
2470	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free_clone < *nblocks);
2471	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free < *nblocks);
2472	rbm.rgd->rd_reserved -= *nblocks;
2473	rbm.rgd->rd_free_clone -= *nblocks;
2474	rbm.rgd->rd_free -= *nblocks;
2475	spin_unlock(&rbm.rgd->rd_rsspin);
2476	if (dinode) {
2477		u64 generation;
2478
2479		rbm.rgd->rd_dinodes++;
2480		generation = rbm.rgd->rd_igeneration++;
2481		if (generation == 0)
2482			generation = rbm.rgd->rd_igeneration++;
2483		ip->i_generation = generation;
2484	}
2485
2486	gfs2_trans_add_meta(rbm.rgd->rd_gl, rbm.rgd->rd_bits[0].bi_bh);
2487	gfs2_rgrp_out(rbm.rgd, rbm.rgd->rd_bits[0].bi_bh->b_data);
2488	rgrp_unlock_local(rbm.rgd);
2489
2490	gfs2_statfs_change(sdp, 0, -(s64)*nblocks, dinode ? 1 : 0);
2491	if (dinode)
2492		gfs2_trans_remove_revoke(sdp, block, *nblocks);
2493
2494	gfs2_quota_change(ip, *nblocks, ip->i_inode.i_uid, ip->i_inode.i_gid);
2495
 
2496	trace_gfs2_block_alloc(ip, rbm.rgd, block, *nblocks,
2497			       dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2498	*bn = block;
2499	return 0;
2500
2501rgrp_error:
2502	rgrp_unlock_local(rbm.rgd);
2503	gfs2_rgrp_error(rbm.rgd);
2504	return -EIO;
2505}
2506
2507/**
2508 * __gfs2_free_blocks - free a contiguous run of block(s)
2509 * @ip: the inode these blocks are being freed from
2510 * @rgd: the resource group the blocks are in
2511 * @bstart: first block of a run of contiguous blocks
2512 * @blen: the length of the block run
2513 * @meta: 1 if the blocks represent metadata
2514 *
2515 */
2516
2517void __gfs2_free_blocks(struct gfs2_inode *ip, struct gfs2_rgrpd *rgd,
2518			u64 bstart, u32 blen, int meta)
2519{
2520	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 
2521
2522	rgrp_lock_local(rgd);
2523	rgblk_free(sdp, rgd, bstart, blen, GFS2_BLKST_FREE);
 
2524	trace_gfs2_block_alloc(ip, rgd, bstart, blen, GFS2_BLKST_FREE);
2525	rgd->rd_free += blen;
2526	rgd->rd_flags &= ~GFS2_RGF_TRIMMED;
2527	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2528	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2529	rgrp_unlock_local(rgd);
2530
2531	/* Directories keep their data in the metadata address space */
2532	if (meta || ip->i_depth || gfs2_is_jdata(ip))
2533		gfs2_journal_wipe(ip, bstart, blen);
2534}
2535
2536/**
2537 * gfs2_free_meta - free a contiguous run of data block(s)
2538 * @ip: the inode these blocks are being freed from
2539 * @rgd: the resource group the blocks are in
2540 * @bstart: first block of a run of contiguous blocks
2541 * @blen: the length of the block run
2542 *
2543 */
2544
2545void gfs2_free_meta(struct gfs2_inode *ip, struct gfs2_rgrpd *rgd,
2546		    u64 bstart, u32 blen)
2547{
2548	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2549
2550	__gfs2_free_blocks(ip, rgd, bstart, blen, 1);
2551	gfs2_statfs_change(sdp, 0, +blen, 0);
2552	gfs2_quota_change(ip, -(s64)blen, ip->i_inode.i_uid, ip->i_inode.i_gid);
2553}
2554
2555void gfs2_unlink_di(struct inode *inode)
2556{
2557	struct gfs2_inode *ip = GFS2_I(inode);
2558	struct gfs2_sbd *sdp = GFS2_SB(inode);
2559	struct gfs2_rgrpd *rgd;
2560	u64 blkno = ip->i_no_addr;
2561
2562	rgd = gfs2_blk2rgrpd(sdp, blkno, true);
2563	if (!rgd)
2564		return;
2565	rgrp_lock_local(rgd);
2566	rgblk_free(sdp, rgd, blkno, 1, GFS2_BLKST_UNLINKED);
2567	trace_gfs2_block_alloc(ip, rgd, blkno, 1, GFS2_BLKST_UNLINKED);
2568	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2569	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2570	be32_add_cpu(&rgd->rd_rgl->rl_unlinked, 1);
2571	rgrp_unlock_local(rgd);
2572}
2573
2574void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip)
2575{
2576	struct gfs2_sbd *sdp = rgd->rd_sbd;
 
 
 
 
 
 
2577
2578	rgrp_lock_local(rgd);
2579	rgblk_free(sdp, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE);
2580	if (!rgd->rd_dinodes)
2581		gfs2_consist_rgrpd(rgd);
2582	rgd->rd_dinodes--;
2583	rgd->rd_free++;
2584
2585	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2586	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2587	be32_add_cpu(&rgd->rd_rgl->rl_unlinked, -1);
2588	rgrp_unlock_local(rgd);
2589
2590	gfs2_statfs_change(sdp, 0, +1, -1);
 
 
 
 
 
 
2591	trace_gfs2_block_alloc(ip, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE);
2592	gfs2_quota_change(ip, -1, ip->i_inode.i_uid, ip->i_inode.i_gid);
2593	gfs2_journal_wipe(ip, ip->i_no_addr, 1);
2594}
2595
2596/**
2597 * gfs2_check_blk_type - Check the type of a block
2598 * @sdp: The superblock
2599 * @no_addr: The block number to check
2600 * @type: The block type we are looking for
2601 *
2602 * The inode glock of @no_addr must be held.  The @type to check for is either
2603 * GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED; checking for type GFS2_BLKST_FREE
2604 * or GFS2_BLKST_USED would make no sense.
2605 *
2606 * Returns: 0 if the block type matches the expected type
2607 *          -ESTALE if it doesn't match
2608 *          or -ve errno if something went wrong while checking
2609 */
2610
2611int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
2612{
2613	struct gfs2_rgrpd *rgd;
2614	struct gfs2_holder rgd_gh;
2615	struct gfs2_rbm rbm;
2616	int error = -EINVAL;
2617
2618	rgd = gfs2_blk2rgrpd(sdp, no_addr, 1);
2619	if (!rgd)
2620		goto fail;
2621
2622	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
2623	if (error)
2624		goto fail;
2625
2626	rbm.rgd = rgd;
2627	error = gfs2_rbm_from_block(&rbm, no_addr);
2628	if (!WARN_ON_ONCE(error)) {
2629		/*
2630		 * No need to take the local resource group lock here; the
2631		 * inode glock of @no_addr provides the necessary
2632		 * synchronization in case the block is an inode.  (In case
2633		 * the block is not an inode, the block type will not match
2634		 * the @type we are looking for.)
2635		 */
2636		if (gfs2_testbit(&rbm, false) != type)
2637			error = -ESTALE;
2638	}
2639
2640	gfs2_glock_dq_uninit(&rgd_gh);
2641
2642fail:
2643	return error;
2644}
2645
2646/**
2647 * gfs2_rlist_add - add a RG to a list of RGs
2648 * @ip: the inode
2649 * @rlist: the list of resource groups
2650 * @block: the block
2651 *
2652 * Figure out what RG a block belongs to and add that RG to the list
2653 *
2654 * FIXME: Don't use NOFAIL
2655 *
2656 */
2657
2658void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
2659		    u64 block)
2660{
2661	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2662	struct gfs2_rgrpd *rgd;
2663	struct gfs2_rgrpd **tmp;
2664	unsigned int new_space;
2665	unsigned int x;
2666
2667	if (gfs2_assert_warn(sdp, !rlist->rl_ghs))
2668		return;
2669
2670	/*
2671	 * The resource group last accessed is kept in the last position.
2672	 */
2673
2674	if (rlist->rl_rgrps) {
2675		rgd = rlist->rl_rgd[rlist->rl_rgrps - 1];
2676		if (rgrp_contains_block(rgd, block))
2677			return;
2678		rgd = gfs2_blk2rgrpd(sdp, block, 1);
2679	} else {
2680		rgd = ip->i_res.rs_rgd;
2681		if (!rgd || !rgrp_contains_block(rgd, block))
2682			rgd = gfs2_blk2rgrpd(sdp, block, 1);
2683	}
2684
2685	if (!rgd) {
2686		fs_err(sdp, "rlist_add: no rgrp for block %llu\n",
2687		       (unsigned long long)block);
2688		return;
2689	}
 
2690
2691	for (x = 0; x < rlist->rl_rgrps; x++) {
2692		if (rlist->rl_rgd[x] == rgd) {
2693			swap(rlist->rl_rgd[x],
2694			     rlist->rl_rgd[rlist->rl_rgrps - 1]);
2695			return;
2696		}
2697	}
2698
2699	if (rlist->rl_rgrps == rlist->rl_space) {
2700		new_space = rlist->rl_space + 10;
2701
2702		tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *),
2703			      GFP_NOFS | __GFP_NOFAIL);
2704
2705		if (rlist->rl_rgd) {
2706			memcpy(tmp, rlist->rl_rgd,
2707			       rlist->rl_space * sizeof(struct gfs2_rgrpd *));
2708			kfree(rlist->rl_rgd);
2709		}
2710
2711		rlist->rl_space = new_space;
2712		rlist->rl_rgd = tmp;
2713	}
2714
2715	rlist->rl_rgd[rlist->rl_rgrps++] = rgd;
2716}
2717
2718/**
2719 * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate
2720 *      and initialize an array of glock holders for them
2721 * @rlist: the list of resource groups
2722 * @state: the state we're requesting
2723 * @flags: the modifier flags
2724 *
2725 * FIXME: Don't use NOFAIL
2726 *
2727 */
2728
2729void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist,
2730		      unsigned int state, u16 flags)
2731{
2732	unsigned int x;
2733
2734	rlist->rl_ghs = kmalloc_array(rlist->rl_rgrps,
2735				      sizeof(struct gfs2_holder),
2736				      GFP_NOFS | __GFP_NOFAIL);
2737	for (x = 0; x < rlist->rl_rgrps; x++)
2738		gfs2_holder_init(rlist->rl_rgd[x]->rd_gl, state, flags,
2739				 &rlist->rl_ghs[x]);
 
2740}
2741
2742/**
2743 * gfs2_rlist_free - free a resource group list
2744 * @rlist: the list of resource groups
2745 *
2746 */
2747
2748void gfs2_rlist_free(struct gfs2_rgrp_list *rlist)
2749{
2750	unsigned int x;
2751
2752	kfree(rlist->rl_rgd);
2753
2754	if (rlist->rl_ghs) {
2755		for (x = 0; x < rlist->rl_rgrps; x++)
2756			gfs2_holder_uninit(&rlist->rl_ghs[x]);
2757		kfree(rlist->rl_ghs);
2758		rlist->rl_ghs = NULL;
2759	}
2760}
2761
2762void rgrp_lock_local(struct gfs2_rgrpd *rgd)
2763{
2764	mutex_lock(&rgd->rd_mutex);
2765}
2766
2767void rgrp_unlock_local(struct gfs2_rgrpd *rgd)
2768{
2769	mutex_unlock(&rgd->rd_mutex);
2770}