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v6.2
   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
 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 patter 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\n"
 818			"ri_length = %u\n"
 819			"ri_data0 = %llu\n"
 820			"ri_data = %u\n"
 821			"ri_bitbytes = %u\n"
 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 * @gh: the glock holder 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_delete_work(gl, 0))
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
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	u32 skip;
1991
1992	get_random_bytes(&skip, sizeof(skip));
1993	return skip % sdp->sd_rgrps;
1994}
1995
1996static bool gfs2_select_rgrp(struct gfs2_rgrpd **pos, const struct gfs2_rgrpd *begin)
1997{
1998	struct gfs2_rgrpd *rgd = *pos;
1999	struct gfs2_sbd *sdp = rgd->rd_sbd;
2000
2001	rgd = gfs2_rgrpd_get_next(rgd);
2002	if (rgd == NULL)
2003		rgd = gfs2_rgrpd_get_first(sdp);
2004	*pos = rgd;
2005	if (rgd != begin) /* If we didn't wrap */
2006		return true;
2007	return false;
2008}
2009
2010/**
2011 * fast_to_acquire - determine if a resource group will be fast to acquire
2012 * @rgd: The rgrp
2013 *
2014 * If this is one of our preferred rgrps, it should be quicker to acquire,
2015 * because we tried to set ourselves up as dlm lock master.
2016 */
2017static inline int fast_to_acquire(struct gfs2_rgrpd *rgd)
2018{
2019	struct gfs2_glock *gl = rgd->rd_gl;
2020
2021	if (gl->gl_state != LM_ST_UNLOCKED && list_empty(&gl->gl_holders) &&
2022	    !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
2023	    !test_bit(GLF_DEMOTE, &gl->gl_flags))
2024		return 1;
2025	if (rgd->rd_flags & GFS2_RDF_PREFERRED)
2026		return 1;
2027	return 0;
2028}
2029
2030/**
2031 * gfs2_inplace_reserve - Reserve space in the filesystem
2032 * @ip: the inode to reserve space for
2033 * @ap: the allocation parameters
2034 *
2035 * We try our best to find an rgrp that has at least ap->target blocks
2036 * available. After a couple of passes (loops == 2), the prospects of finding
2037 * such an rgrp diminish. At this stage, we return the first rgrp that has
2038 * at least ap->min_target blocks available.
 
2039 *
2040 * Returns: 0 on success,
2041 *          -ENOMEM if a suitable rgrp can't be found
2042 *          errno otherwise
2043 */
2044
2045int gfs2_inplace_reserve(struct gfs2_inode *ip, struct gfs2_alloc_parms *ap)
2046{
2047	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2048	struct gfs2_rgrpd *begin = NULL;
2049	struct gfs2_blkreserv *rs = &ip->i_res;
2050	int error = 0, flags = LM_FLAG_NODE_SCOPE;
2051	bool rg_locked;
2052	u64 last_unlinked = NO_BLOCK;
2053	u32 target = ap->target;
2054	int loops = 0;
2055	u32 free_blocks, blocks_available, skip = 0;
2056
2057	BUG_ON(rs->rs_reserved);
2058
2059	if (sdp->sd_args.ar_rgrplvb)
2060		flags |= GL_SKIP;
2061	if (gfs2_assert_warn(sdp, target))
2062		return -EINVAL;
2063	if (gfs2_rs_active(rs)) {
2064		begin = rs->rs_rgd;
2065	} else if (rs->rs_rgd &&
2066		   rgrp_contains_block(rs->rs_rgd, ip->i_goal)) {
2067		begin = rs->rs_rgd;
2068	} else {
2069		check_and_update_goal(ip);
2070		rs->rs_rgd = begin = gfs2_blk2rgrpd(sdp, ip->i_goal, 1);
2071	}
2072	if (S_ISDIR(ip->i_inode.i_mode) && (ap->aflags & GFS2_AF_ORLOV))
2073		skip = gfs2_orlov_skip(ip);
2074	if (rs->rs_rgd == NULL)
2075		return -EBADSLT;
2076
2077	while (loops < 3) {
2078		struct gfs2_rgrpd *rgd;
2079
2080		rg_locked = gfs2_glock_is_locked_by_me(rs->rs_rgd->rd_gl);
2081		if (rg_locked) {
2082			rgrp_lock_local(rs->rs_rgd);
2083		} else {
2084			if (skip && skip--)
2085				goto next_rgrp;
2086			if (!gfs2_rs_active(rs)) {
2087				if (loops == 0 &&
2088				    !fast_to_acquire(rs->rs_rgd))
2089					goto next_rgrp;
2090				if ((loops < 2) &&
2091				    gfs2_rgrp_used_recently(rs, 1000) &&
2092				    gfs2_rgrp_congested(rs->rs_rgd, loops))
2093					goto next_rgrp;
2094			}
2095			error = gfs2_glock_nq_init(rs->rs_rgd->rd_gl,
2096						   LM_ST_EXCLUSIVE, flags,
2097						   &ip->i_rgd_gh);
2098			if (unlikely(error))
2099				return error;
2100			rgrp_lock_local(rs->rs_rgd);
2101			if (!gfs2_rs_active(rs) && (loops < 2) &&
2102			    gfs2_rgrp_congested(rs->rs_rgd, loops))
2103				goto skip_rgrp;
2104			if (sdp->sd_args.ar_rgrplvb) {
2105				error = update_rgrp_lvb(rs->rs_rgd,
2106							&ip->i_rgd_gh);
2107				if (unlikely(error)) {
2108					rgrp_unlock_local(rs->rs_rgd);
2109					gfs2_glock_dq_uninit(&ip->i_rgd_gh);
2110					return error;
2111				}
2112			}
2113		}
2114
2115		/* Skip unusable resource groups */
2116		if ((rs->rs_rgd->rd_flags & (GFS2_RGF_NOALLOC |
2117						 GFS2_RDF_ERROR)) ||
2118		    (loops == 0 && target > rs->rs_rgd->rd_extfail_pt))
2119			goto skip_rgrp;
2120
2121		if (sdp->sd_args.ar_rgrplvb) {
2122			error = gfs2_instantiate(&ip->i_rgd_gh);
2123			if (error)
2124				goto skip_rgrp;
2125		}
2126
2127		/* Get a reservation if we don't already have one */
2128		if (!gfs2_rs_active(rs))
2129			rg_mblk_search(rs->rs_rgd, ip, ap);
2130
2131		/* Skip rgrps when we can't get a reservation on first pass */
2132		if (!gfs2_rs_active(rs) && (loops < 1))
2133			goto check_rgrp;
2134
2135		/* If rgrp has enough free space, use it */
2136		rgd = rs->rs_rgd;
2137		spin_lock(&rgd->rd_rsspin);
2138		free_blocks = rgd_free(rgd, rs);
2139		blocks_available = rgd->rd_free_clone - rgd->rd_reserved;
2140		if (free_blocks < target || blocks_available < target) {
2141			spin_unlock(&rgd->rd_rsspin);
2142			goto check_rgrp;
2143		}
2144		rs->rs_reserved = ap->target;
2145		if (rs->rs_reserved > blocks_available)
2146			rs->rs_reserved = blocks_available;
2147		rgd->rd_reserved += rs->rs_reserved;
2148		spin_unlock(&rgd->rd_rsspin);
2149		rgrp_unlock_local(rs->rs_rgd);
2150		return 0;
2151check_rgrp:
2152		/* Check for unlinked inodes which can be reclaimed */
2153		if (rs->rs_rgd->rd_flags & GFS2_RDF_CHECK)
2154			try_rgrp_unlink(rs->rs_rgd, &last_unlinked,
2155					ip->i_no_addr);
2156skip_rgrp:
2157		rgrp_unlock_local(rs->rs_rgd);
2158
2159		/* Drop reservation, if we couldn't use reserved rgrp */
2160		if (gfs2_rs_active(rs))
2161			gfs2_rs_deltree(rs);
2162
2163		/* Unlock rgrp if required */
2164		if (!rg_locked)
2165			gfs2_glock_dq_uninit(&ip->i_rgd_gh);
2166next_rgrp:
2167		/* Find the next rgrp, and continue looking */
2168		if (gfs2_select_rgrp(&rs->rs_rgd, begin))
2169			continue;
2170		if (skip)
2171			continue;
2172
2173		/* If we've scanned all the rgrps, but found no free blocks
2174		 * then this checks for some less likely conditions before
2175		 * trying again.
2176		 */
2177		loops++;
2178		/* Check that fs hasn't grown if writing to rindex */
2179		if (ip == GFS2_I(sdp->sd_rindex) && !sdp->sd_rindex_uptodate) {
2180			error = gfs2_ri_update(ip);
2181			if (error)
2182				return error;
2183		}
2184		/* Flushing the log may release space */
2185		if (loops == 2) {
2186			if (ap->min_target)
2187				target = ap->min_target;
2188			gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
2189				       GFS2_LFC_INPLACE_RESERVE);
2190		}
2191	}
2192
2193	return -ENOSPC;
2194}
2195
2196/**
2197 * gfs2_inplace_release - release an inplace reservation
2198 * @ip: the inode the reservation was taken out on
2199 *
2200 * Release a reservation made by gfs2_inplace_reserve().
2201 */
2202
2203void gfs2_inplace_release(struct gfs2_inode *ip)
2204{
2205	struct gfs2_blkreserv *rs = &ip->i_res;
2206
2207	if (rs->rs_reserved) {
2208		struct gfs2_rgrpd *rgd = rs->rs_rgd;
 
2209
2210		spin_lock(&rgd->rd_rsspin);
2211		GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved < rs->rs_reserved);
2212		rgd->rd_reserved -= rs->rs_reserved;
2213		spin_unlock(&rgd->rd_rsspin);
2214		rs->rs_reserved = 0;
2215	}
2216	if (gfs2_holder_initialized(&ip->i_rgd_gh))
2217		gfs2_glock_dq_uninit(&ip->i_rgd_gh);
 
 
 
 
 
 
 
 
 
2218}
2219
 
2220/**
2221 * gfs2_alloc_extent - allocate an extent from a given bitmap
2222 * @rbm: the resource group information
2223 * @dinode: TRUE if the first block we allocate is for a dinode
2224 * @n: The extent length (value/result)
2225 *
2226 * Add the bitmap buffer to the transaction.
2227 * Set the found bits to @new_state to change block's allocation state.
2228 */
2229static void gfs2_alloc_extent(const struct gfs2_rbm *rbm, bool dinode,
2230			     unsigned int *n)
2231{
2232	struct gfs2_rbm pos = { .rgd = rbm->rgd, };
2233	const unsigned int elen = *n;
2234	u64 block;
2235	int ret;
2236
2237	*n = 1;
2238	block = gfs2_rbm_to_block(rbm);
2239	gfs2_trans_add_meta(rbm->rgd->rd_gl, rbm_bi(rbm)->bi_bh);
2240	gfs2_setbit(rbm, true, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2241	block++;
2242	while (*n < elen) {
2243		ret = gfs2_rbm_from_block(&pos, block);
2244		if (ret || gfs2_testbit(&pos, true) != GFS2_BLKST_FREE)
2245			break;
2246		gfs2_trans_add_meta(pos.rgd->rd_gl, rbm_bi(&pos)->bi_bh);
2247		gfs2_setbit(&pos, true, GFS2_BLKST_USED);
2248		(*n)++;
2249		block++;
2250	}
2251}
2252
2253/**
2254 * rgblk_free - Change alloc state of given block(s)
2255 * @sdp: the filesystem
2256 * @rgd: the resource group the blocks are in
2257 * @bstart: the start of a run of blocks to free
2258 * @blen: the length of the block run (all must lie within ONE RG!)
2259 * @new_state: GFS2_BLKST_XXX the after-allocation block state
 
 
2260 */
2261
2262static void rgblk_free(struct gfs2_sbd *sdp, struct gfs2_rgrpd *rgd,
2263		       u64 bstart, u32 blen, unsigned char new_state)
2264{
2265	struct gfs2_rbm rbm;
2266	struct gfs2_bitmap *bi, *bi_prev = NULL;
2267
2268	rbm.rgd = rgd;
2269	if (WARN_ON_ONCE(gfs2_rbm_from_block(&rbm, bstart)))
2270		return;
 
 
 
 
 
2271	while (blen--) {
2272		bi = rbm_bi(&rbm);
2273		if (bi != bi_prev) {
2274			if (!bi->bi_clone) {
2275				bi->bi_clone = kmalloc(bi->bi_bh->b_size,
2276						      GFP_NOFS | __GFP_NOFAIL);
2277				memcpy(bi->bi_clone + bi->bi_offset,
2278				       bi->bi_bh->b_data + bi->bi_offset,
2279				       bi->bi_bytes);
2280			}
2281			gfs2_trans_add_meta(rbm.rgd->rd_gl, bi->bi_bh);
2282			bi_prev = bi;
2283		}
2284		gfs2_setbit(&rbm, false, new_state);
2285		gfs2_rbm_add(&rbm, 1);
2286	}
 
 
2287}
2288
2289/**
2290 * gfs2_rgrp_dump - print out an rgrp
2291 * @seq: The iterator
2292 * @rgd: The rgrp in question
2293 * @fs_id_buf: pointer to file system id (if requested)
2294 *
2295 */
2296
2297void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_rgrpd *rgd,
2298		    const char *fs_id_buf)
2299{
 
2300	struct gfs2_blkreserv *trs;
2301	const struct rb_node *n;
2302
2303	spin_lock(&rgd->rd_rsspin);
2304	gfs2_print_dbg(seq, "%s R: n:%llu f:%02x b:%u/%u i:%u q:%u r:%u e:%u\n",
2305		       fs_id_buf,
2306		       (unsigned long long)rgd->rd_addr, rgd->rd_flags,
2307		       rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes,
2308		       rgd->rd_requested, rgd->rd_reserved, rgd->rd_extfail_pt);
2309	if (rgd->rd_sbd->sd_args.ar_rgrplvb) {
2310		struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
2311
2312		gfs2_print_dbg(seq, "%s  L: f:%02x b:%u i:%u\n", fs_id_buf,
2313			       be32_to_cpu(rgl->rl_flags),
2314			       be32_to_cpu(rgl->rl_free),
2315			       be32_to_cpu(rgl->rl_dinodes));
2316	}
2317	for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) {
2318		trs = rb_entry(n, struct gfs2_blkreserv, rs_node);
2319		dump_rs(seq, trs, fs_id_buf);
2320	}
2321	spin_unlock(&rgd->rd_rsspin);
2322}
2323
2324static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd)
2325{
2326	struct gfs2_sbd *sdp = rgd->rd_sbd;
2327	char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
2328
2329	fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n",
2330		(unsigned long long)rgd->rd_addr);
2331	fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n");
2332	sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
2333	gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
2334	rgd->rd_flags |= GFS2_RDF_ERROR;
2335}
2336
2337/**
2338 * gfs2_adjust_reservation - Adjust (or remove) a reservation after allocation
2339 * @ip: The inode we have just allocated blocks for
2340 * @rbm: The start of the allocated blocks
2341 * @len: The extent length
2342 *
2343 * Adjusts a reservation after an allocation has taken place. If the
2344 * reservation does not match the allocation, or if it is now empty
2345 * then it is removed.
2346 */
2347
2348static void gfs2_adjust_reservation(struct gfs2_inode *ip,
2349				    const struct gfs2_rbm *rbm, unsigned len)
2350{
2351	struct gfs2_blkreserv *rs = &ip->i_res;
2352	struct gfs2_rgrpd *rgd = rbm->rgd;
 
 
 
2353
2354	BUG_ON(rs->rs_reserved < len);
2355	rs->rs_reserved -= len;
2356	if (gfs2_rs_active(rs)) {
2357		u64 start = gfs2_rbm_to_block(rbm);
2358
2359		if (rs->rs_start == start) {
2360			unsigned int rlen;
2361
2362			rs->rs_start += len;
2363			rlen = min(rs->rs_requested, len);
2364			rs->rs_requested -= rlen;
2365			rgd->rd_requested -= rlen;
2366			trace_gfs2_rs(rs, TRACE_RS_CLAIM);
2367			if (rs->rs_start < rgd->rd_data0 + rgd->rd_data &&
2368			    rs->rs_requested)
2369				return;
2370			/* We used up our block reservation, so we should
2371			   reserve more blocks next time. */
2372			atomic_add(RGRP_RSRV_ADDBLKS, &ip->i_sizehint);
2373		}
2374		__rs_deltree(rs);
2375	}
 
 
2376}
2377
2378/**
2379 * gfs2_set_alloc_start - Set starting point for block allocation
2380 * @rbm: The rbm which will be set to the required location
2381 * @ip: The gfs2 inode
2382 * @dinode: Flag to say if allocation includes a new inode
2383 *
2384 * This sets the starting point from the reservation if one is active
2385 * otherwise it falls back to guessing a start point based on the
2386 * inode's goal block or the last allocation point in the rgrp.
2387 */
2388
2389static void gfs2_set_alloc_start(struct gfs2_rbm *rbm,
2390				 const struct gfs2_inode *ip, bool dinode)
2391{
2392	u64 goal;
2393
2394	if (gfs2_rs_active(&ip->i_res)) {
2395		goal = ip->i_res.rs_start;
2396	} else {
2397		if (!dinode && rgrp_contains_block(rbm->rgd, ip->i_goal))
2398			goal = ip->i_goal;
2399		else
2400			goal = rbm->rgd->rd_last_alloc + rbm->rgd->rd_data0;
2401	}
2402	if (WARN_ON_ONCE(gfs2_rbm_from_block(rbm, goal))) {
2403		rbm->bii = 0;
2404		rbm->offset = 0;
2405	}
 
 
 
 
 
 
 
2406}
2407
2408/**
2409 * gfs2_alloc_blocks - Allocate one or more blocks of data and/or a dinode
2410 * @ip: the inode to allocate the block for
2411 * @bn: Used to return the starting block number
2412 * @nblocks: requested number of blocks/extent length (value/result)
2413 * @dinode: 1 if we're allocating a dinode block, else 0
2414 * @generation: the generation number of the inode
2415 *
2416 * Returns: 0 or error
2417 */
2418
2419int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *nblocks,
2420		      bool dinode, u64 *generation)
2421{
2422	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2423	struct buffer_head *dibh;
2424	struct gfs2_rbm rbm = { .rgd = ip->i_res.rs_rgd, };
 
2425	u64 block; /* block, within the file system scope */
2426	u32 minext = 1;
2427	int error = -ENOSPC;
2428
2429	BUG_ON(ip->i_res.rs_reserved < *nblocks);
 
2430
2431	rgrp_lock_local(rbm.rgd);
2432	if (gfs2_rs_active(&ip->i_res)) {
2433		gfs2_set_alloc_start(&rbm, ip, dinode);
2434		error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, &ip->i_res, false);
2435	}
2436	if (error == -ENOSPC) {
2437		gfs2_set_alloc_start(&rbm, ip, dinode);
2438		error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, NULL, false);
2439	}
2440
2441	/* Since all blocks are reserved in advance, this shouldn't happen */
2442	if (error) {
2443		fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d fail_pt=%d\n",
2444			(unsigned long long)ip->i_no_addr, error, *nblocks,
2445			test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags),
2446			rbm.rgd->rd_extfail_pt);
2447		goto rgrp_error;
2448	}
2449
2450	gfs2_alloc_extent(&rbm, dinode, nblocks);
2451	block = gfs2_rbm_to_block(&rbm);
2452	rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0;
 
 
 
 
 
 
2453	if (!dinode) {
2454		ip->i_goal = block + *nblocks - 1;
2455		error = gfs2_meta_inode_buffer(ip, &dibh);
2456		if (error == 0) {
2457			struct gfs2_dinode *di =
2458				(struct gfs2_dinode *)dibh->b_data;
2459			gfs2_trans_add_meta(ip->i_gl, dibh);
2460			di->di_goal_meta = di->di_goal_data =
2461				cpu_to_be64(ip->i_goal);
2462			brelse(dibh);
2463		}
2464	}
2465	spin_lock(&rbm.rgd->rd_rsspin);
2466	gfs2_adjust_reservation(ip, &rbm, *nblocks);
2467	if (rbm.rgd->rd_free < *nblocks || rbm.rgd->rd_reserved < *nblocks) {
2468		fs_warn(sdp, "nblocks=%u\n", *nblocks);
2469		spin_unlock(&rbm.rgd->rd_rsspin);
2470		goto rgrp_error;
2471	}
2472	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_reserved < *nblocks);
2473	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free_clone < *nblocks);
2474	GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free < *nblocks);
2475	rbm.rgd->rd_reserved -= *nblocks;
2476	rbm.rgd->rd_free_clone -= *nblocks;
2477	rbm.rgd->rd_free -= *nblocks;
2478	spin_unlock(&rbm.rgd->rd_rsspin);
2479	if (dinode) {
2480		rbm.rgd->rd_dinodes++;
2481		*generation = rbm.rgd->rd_igeneration++;
2482		if (*generation == 0)
2483			*generation = rbm.rgd->rd_igeneration++;
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	rgrp_unlock_local(rgd);
2588	be32_add_cpu(&rgd->rd_rgl->rl_unlinked, -1);
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}
v4.10.11
 
   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
  78
  79/**
  80 * gfs2_setbit - Set a bit in the bitmaps
  81 * @rbm: The position of the bit to set
  82 * @do_clone: Also set the clone bitmap, if it exists
  83 * @new_state: the new state of the block
  84 *
  85 */
  86
  87static inline void gfs2_setbit(const struct gfs2_rbm *rbm, bool do_clone,
  88			       unsigned char new_state)
  89{
  90	unsigned char *byte1, *byte2, *end, cur_state;
  91	struct gfs2_bitmap *bi = rbm_bi(rbm);
  92	unsigned int buflen = bi->bi_len;
  93	const unsigned int bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
  94
  95	byte1 = bi->bi_bh->b_data + bi->bi_offset + (rbm->offset / GFS2_NBBY);
  96	end = bi->bi_bh->b_data + bi->bi_offset + buflen;
  97
  98	BUG_ON(byte1 >= end);
  99
 100	cur_state = (*byte1 >> bit) & GFS2_BIT_MASK;
 101
 102	if (unlikely(!valid_change[new_state * 4 + cur_state])) {
 103		pr_warn("buf_blk = 0x%x old_state=%d, new_state=%d\n",
 
 
 104			rbm->offset, cur_state, new_state);
 105		pr_warn("rgrp=0x%llx bi_start=0x%x\n",
 106			(unsigned long long)rbm->rgd->rd_addr, bi->bi_start);
 107		pr_warn("bi_offset=0x%x bi_len=0x%x\n",
 108			bi->bi_offset, bi->bi_len);
 
 
 109		dump_stack();
 110		gfs2_consist_rgrpd(rbm->rgd);
 111		return;
 112	}
 113	*byte1 ^= (cur_state ^ new_state) << bit;
 114
 115	if (do_clone && bi->bi_clone) {
 116		byte2 = bi->bi_clone + bi->bi_offset + (rbm->offset / GFS2_NBBY);
 117		cur_state = (*byte2 >> bit) & GFS2_BIT_MASK;
 118		*byte2 ^= (cur_state ^ new_state) << bit;
 119	}
 120}
 121
 122/**
 123 * gfs2_testbit - test a bit in the bitmaps
 124 * @rbm: The bit to test
 
 
 
 
 125 *
 126 * Returns: The two bit block state of the requested bit
 127 */
 128
 129static inline u8 gfs2_testbit(const struct gfs2_rbm *rbm)
 130{
 131	struct gfs2_bitmap *bi = rbm_bi(rbm);
 132	const u8 *buffer = bi->bi_bh->b_data + bi->bi_offset;
 133	const u8 *byte;
 134	unsigned int bit;
 135
 
 
 
 
 
 136	byte = buffer + (rbm->offset / GFS2_NBBY);
 137	bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE;
 138
 139	return (*byte >> bit) & GFS2_BIT_MASK;
 140}
 141
 142/**
 143 * gfs2_bit_search
 144 * @ptr: Pointer to bitmap data
 145 * @mask: Mask to use (normally 0x55555.... but adjusted for search start)
 146 * @state: The state we are searching for
 147 *
 148 * We xor the bitmap data with a patter which is the bitwise opposite
 149 * of what we are looking for, this gives rise to a pattern of ones
 150 * wherever there is a match. Since we have two bits per entry, we
 151 * take this pattern, shift it down by one place and then and it with
 152 * the original. All the even bit positions (0,2,4, etc) then represent
 153 * successful matches, so we mask with 0x55555..... to remove the unwanted
 154 * odd bit positions.
 155 *
 156 * This allows searching of a whole u64 at once (32 blocks) with a
 157 * single test (on 64 bit arches).
 158 */
 159
 160static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state)
 161{
 162	u64 tmp;
 163	static const u64 search[] = {
 164		[0] = 0xffffffffffffffffULL,
 165		[1] = 0xaaaaaaaaaaaaaaaaULL,
 166		[2] = 0x5555555555555555ULL,
 167		[3] = 0x0000000000000000ULL,
 168	};
 169	tmp = le64_to_cpu(*ptr) ^ search[state];
 170	tmp &= (tmp >> 1);
 171	tmp &= mask;
 172	return tmp;
 173}
 174
 175/**
 176 * rs_cmp - multi-block reservation range compare
 177 * @blk: absolute file system block number of the new reservation
 178 * @len: number of blocks in the new reservation
 179 * @rs: existing reservation to compare against
 180 *
 181 * returns: 1 if the block range is beyond the reach of the reservation
 182 *         -1 if the block range is before the start of the reservation
 183 *          0 if the block range overlaps with the reservation
 184 */
 185static inline int rs_cmp(u64 blk, u32 len, struct gfs2_blkreserv *rs)
 186{
 187	u64 startblk = gfs2_rbm_to_block(&rs->rs_rbm);
 188
 189	if (blk >= startblk + rs->rs_free)
 190		return 1;
 191	if (blk + len - 1 < startblk)
 192		return -1;
 193	return 0;
 194}
 195
 196/**
 197 * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing
 198 *       a block in a given allocation state.
 199 * @buf: the buffer that holds the bitmaps
 200 * @len: the length (in bytes) of the buffer
 201 * @goal: start search at this block's bit-pair (within @buffer)
 202 * @state: GFS2_BLKST_XXX the state of the block we're looking for.
 203 *
 204 * Scope of @goal and returned block number is only within this bitmap buffer,
 205 * not entire rgrp or filesystem.  @buffer will be offset from the actual
 206 * beginning of a bitmap block buffer, skipping any header structures, but
 207 * headers are always a multiple of 64 bits long so that the buffer is
 208 * always aligned to a 64 bit boundary.
 209 *
 210 * The size of the buffer is in bytes, but is it assumed that it is
 211 * always ok to read a complete multiple of 64 bits at the end
 212 * of the block in case the end is no aligned to a natural boundary.
 213 *
 214 * Return: the block number (bitmap buffer scope) that was found
 215 */
 216
 217static u32 gfs2_bitfit(const u8 *buf, const unsigned int len,
 218		       u32 goal, u8 state)
 219{
 220	u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1);
 221	const __le64 *ptr = ((__le64 *)buf) + (goal >> 5);
 222	const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64)));
 223	u64 tmp;
 224	u64 mask = 0x5555555555555555ULL;
 225	u32 bit;
 226
 227	/* Mask off bits we don't care about at the start of the search */
 228	mask <<= spoint;
 229	tmp = gfs2_bit_search(ptr, mask, state);
 230	ptr++;
 231	while(tmp == 0 && ptr < end) {
 232		tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state);
 233		ptr++;
 234	}
 235	/* Mask off any bits which are more than len bytes from the start */
 236	if (ptr == end && (len & (sizeof(u64) - 1)))
 237		tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1))));
 238	/* Didn't find anything, so return */
 239	if (tmp == 0)
 240		return BFITNOENT;
 241	ptr--;
 242	bit = __ffs64(tmp);
 243	bit /= 2;	/* two bits per entry in the bitmap */
 244	return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit;
 245}
 246
 247/**
 248 * gfs2_rbm_from_block - Set the rbm based upon rgd and block number
 249 * @rbm: The rbm with rgd already set correctly
 250 * @block: The block number (filesystem relative)
 251 *
 252 * This sets the bi and offset members of an rbm based on a
 253 * resource group and a filesystem relative block number. The
 254 * resource group must be set in the rbm on entry, the bi and
 255 * offset members will be set by this function.
 256 *
 257 * Returns: 0 on success, or an error code
 258 */
 259
 260static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block)
 261{
 262	u64 rblock = block - rbm->rgd->rd_data0;
 263
 264	if (WARN_ON_ONCE(rblock > UINT_MAX))
 265		return -EINVAL;
 266	if (block >= rbm->rgd->rd_data0 + rbm->rgd->rd_data)
 267		return -E2BIG;
 268
 269	rbm->bii = 0;
 270	rbm->offset = (u32)(rblock);
 271	/* Check if the block is within the first block */
 272	if (rbm->offset < rbm_bi(rbm)->bi_blocks)
 273		return 0;
 274
 275	/* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */
 276	rbm->offset += (sizeof(struct gfs2_rgrp) -
 277			sizeof(struct gfs2_meta_header)) * GFS2_NBBY;
 278	rbm->bii = rbm->offset / rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 279	rbm->offset -= rbm->bii * rbm->rgd->rd_sbd->sd_blocks_per_bitmap;
 280	return 0;
 281}
 282
 283/**
 284 * gfs2_rbm_incr - increment an rbm structure
 285 * @rbm: The rbm with rgd already set correctly
 
 286 *
 287 * This function takes an existing rbm structure and increments it to the next
 288 * viable block offset.
 289 *
 290 * Returns: If incrementing the offset would cause the rbm to go past the
 291 *          end of the rgrp, true is returned, otherwise false.
 292 *
 
 293 */
 294
 295static bool gfs2_rbm_incr(struct gfs2_rbm *rbm)
 296{
 297	if (rbm->offset + 1 < rbm_bi(rbm)->bi_blocks) { /* in the same bitmap */
 298		rbm->offset++;
 
 
 
 299		return false;
 300	}
 301	if (rbm->bii == rbm->rgd->rd_length - 1) /* at the last bitmap */
 302		return true;
 303
 304	rbm->offset = 0;
 305	rbm->bii++;
 306	return false;
 
 
 
 
 
 
 
 
 307}
 308
 309/**
 310 * gfs2_unaligned_extlen - Look for free blocks which are not byte aligned
 311 * @rbm: Position to search (value/result)
 312 * @n_unaligned: Number of unaligned blocks to check
 313 * @len: Decremented for each block found (terminate on zero)
 314 *
 315 * Returns: true if a non-free block is encountered
 
 316 */
 317
 318static bool gfs2_unaligned_extlen(struct gfs2_rbm *rbm, u32 n_unaligned, u32 *len)
 319{
 320	u32 n;
 321	u8 res;
 322
 323	for (n = 0; n < n_unaligned; n++) {
 324		res = gfs2_testbit(rbm);
 325		if (res != GFS2_BLKST_FREE)
 326			return true;
 327		(*len)--;
 328		if (*len == 0)
 329			return true;
 330		if (gfs2_rbm_incr(rbm))
 331			return true;
 332	}
 333
 334	return false;
 335}
 336
 337/**
 338 * gfs2_free_extlen - Return extent length of free blocks
 339 * @rrbm: Starting position
 340 * @len: Max length to check
 341 *
 342 * Starting at the block specified by the rbm, see how many free blocks
 343 * there are, not reading more than len blocks ahead. This can be done
 344 * using memchr_inv when the blocks are byte aligned, but has to be done
 345 * on a block by block basis in case of unaligned blocks. Also this
 346 * function can cope with bitmap boundaries (although it must stop on
 347 * a resource group boundary)
 348 *
 349 * Returns: Number of free blocks in the extent
 350 */
 351
 352static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len)
 353{
 354	struct gfs2_rbm rbm = *rrbm;
 355	u32 n_unaligned = rbm.offset & 3;
 356	u32 size = len;
 357	u32 bytes;
 358	u32 chunk_size;
 359	u8 *ptr, *start, *end;
 360	u64 block;
 361	struct gfs2_bitmap *bi;
 362
 363	if (n_unaligned &&
 364	    gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len))
 365		goto out;
 366
 367	n_unaligned = len & 3;
 368	/* Start is now byte aligned */
 369	while (len > 3) {
 370		bi = rbm_bi(&rbm);
 371		start = bi->bi_bh->b_data;
 372		if (bi->bi_clone)
 373			start = bi->bi_clone;
 374		end = start + bi->bi_bh->b_size;
 375		start += bi->bi_offset;
 
 376		BUG_ON(rbm.offset & 3);
 377		start += (rbm.offset / GFS2_NBBY);
 378		bytes = min_t(u32, len / GFS2_NBBY, (end - start));
 379		ptr = memchr_inv(start, 0, bytes);
 380		chunk_size = ((ptr == NULL) ? bytes : (ptr - start));
 381		chunk_size *= GFS2_NBBY;
 382		BUG_ON(len < chunk_size);
 383		len -= chunk_size;
 384		block = gfs2_rbm_to_block(&rbm);
 385		if (gfs2_rbm_from_block(&rbm, block + chunk_size)) {
 386			n_unaligned = 0;
 387			break;
 388		}
 389		if (ptr) {
 390			n_unaligned = 3;
 391			break;
 392		}
 393		n_unaligned = len & 3;
 394	}
 395
 396	/* Deal with any bits left over at the end */
 397	if (n_unaligned)
 398		gfs2_unaligned_extlen(&rbm, n_unaligned, &len);
 399out:
 400	return size - len;
 401}
 402
 403/**
 404 * gfs2_bitcount - count the number of bits in a certain state
 405 * @rgd: the resource group descriptor
 406 * @buffer: the buffer that holds the bitmaps
 407 * @buflen: the length (in bytes) of the buffer
 408 * @state: the state of the block we're looking for
 409 *
 410 * Returns: The number of bits
 411 */
 412
 413static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer,
 414			 unsigned int buflen, u8 state)
 415{
 416	const u8 *byte = buffer;
 417	const u8 *end = buffer + buflen;
 418	const u8 state1 = state << 2;
 419	const u8 state2 = state << 4;
 420	const u8 state3 = state << 6;
 421	u32 count = 0;
 422
 423	for (; byte < end; byte++) {
 424		if (((*byte) & 0x03) == state)
 425			count++;
 426		if (((*byte) & 0x0C) == state1)
 427			count++;
 428		if (((*byte) & 0x30) == state2)
 429			count++;
 430		if (((*byte) & 0xC0) == state3)
 431			count++;
 432	}
 433
 434	return count;
 435}
 436
 437/**
 438 * gfs2_rgrp_verify - Verify that a resource group is consistent
 439 * @rgd: the rgrp
 440 *
 441 */
 442
 443void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd)
 444{
 445	struct gfs2_sbd *sdp = rgd->rd_sbd;
 446	struct gfs2_bitmap *bi = NULL;
 447	u32 length = rgd->rd_length;
 448	u32 count[4], tmp;
 449	int buf, x;
 450
 451	memset(count, 0, 4 * sizeof(u32));
 452
 453	/* Count # blocks in each of 4 possible allocation states */
 454	for (buf = 0; buf < length; buf++) {
 455		bi = rgd->rd_bits + buf;
 456		for (x = 0; x < 4; x++)
 457			count[x] += gfs2_bitcount(rgd,
 458						  bi->bi_bh->b_data +
 459						  bi->bi_offset,
 460						  bi->bi_len, x);
 461	}
 462
 463	if (count[0] != rgd->rd_free) {
 464		if (gfs2_consist_rgrpd(rgd))
 465			fs_err(sdp, "free data mismatch:  %u != %u\n",
 466			       count[0], rgd->rd_free);
 467		return;
 468	}
 469
 470	tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes;
 471	if (count[1] != tmp) {
 472		if (gfs2_consist_rgrpd(rgd))
 473			fs_err(sdp, "used data mismatch:  %u != %u\n",
 474			       count[1], tmp);
 475		return;
 476	}
 477
 478	if (count[2] + count[3] != rgd->rd_dinodes) {
 479		if (gfs2_consist_rgrpd(rgd))
 480			fs_err(sdp, "used metadata mismatch:  %u != %u\n",
 481			       count[2] + count[3], rgd->rd_dinodes);
 482		return;
 483	}
 484}
 485
 486static inline int rgrp_contains_block(struct gfs2_rgrpd *rgd, u64 block)
 487{
 488	u64 first = rgd->rd_data0;
 489	u64 last = first + rgd->rd_data;
 490	return first <= block && block < last;
 491}
 492
 493/**
 494 * gfs2_blk2rgrpd - Find resource group for a given data/meta block number
 495 * @sdp: The GFS2 superblock
 496 * @blk: The data block number
 497 * @exact: True if this needs to be an exact match
 498 *
 
 
 
 
 
 
 
 499 * Returns: The resource group, or NULL if not found
 500 */
 501
 502struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact)
 503{
 504	struct rb_node *n, *next;
 505	struct gfs2_rgrpd *cur;
 506
 507	spin_lock(&sdp->sd_rindex_spin);
 508	n = sdp->sd_rindex_tree.rb_node;
 509	while (n) {
 510		cur = rb_entry(n, struct gfs2_rgrpd, rd_node);
 511		next = NULL;
 512		if (blk < cur->rd_addr)
 513			next = n->rb_left;
 514		else if (blk >= cur->rd_data0 + cur->rd_data)
 515			next = n->rb_right;
 516		if (next == NULL) {
 517			spin_unlock(&sdp->sd_rindex_spin);
 518			if (exact) {
 519				if (blk < cur->rd_addr)
 520					return NULL;
 521				if (blk >= cur->rd_data0 + cur->rd_data)
 522					return NULL;
 523			}
 524			return cur;
 525		}
 526		n = next;
 527	}
 528	spin_unlock(&sdp->sd_rindex_spin);
 529
 530	return NULL;
 531}
 532
 533/**
 534 * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem
 535 * @sdp: The GFS2 superblock
 536 *
 537 * Returns: The first rgrp in the filesystem
 538 */
 539
 540struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp)
 541{
 542	const struct rb_node *n;
 543	struct gfs2_rgrpd *rgd;
 544
 545	spin_lock(&sdp->sd_rindex_spin);
 546	n = rb_first(&sdp->sd_rindex_tree);
 547	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 548	spin_unlock(&sdp->sd_rindex_spin);
 549
 550	return rgd;
 551}
 552
 553/**
 554 * gfs2_rgrpd_get_next - get the next RG
 555 * @rgd: the resource group descriptor
 556 *
 557 * Returns: The next rgrp
 558 */
 559
 560struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd)
 561{
 562	struct gfs2_sbd *sdp = rgd->rd_sbd;
 563	const struct rb_node *n;
 564
 565	spin_lock(&sdp->sd_rindex_spin);
 566	n = rb_next(&rgd->rd_node);
 567	if (n == NULL)
 568		n = rb_first(&sdp->sd_rindex_tree);
 569
 570	if (unlikely(&rgd->rd_node == n)) {
 571		spin_unlock(&sdp->sd_rindex_spin);
 572		return NULL;
 573	}
 574	rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 575	spin_unlock(&sdp->sd_rindex_spin);
 576	return rgd;
 577}
 578
 579void check_and_update_goal(struct gfs2_inode *ip)
 580{
 581	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 582	if (!ip->i_goal || gfs2_blk2rgrpd(sdp, ip->i_goal, 1) == NULL)
 583		ip->i_goal = ip->i_no_addr;
 584}
 585
 586void gfs2_free_clones(struct gfs2_rgrpd *rgd)
 587{
 588	int x;
 589
 590	for (x = 0; x < rgd->rd_length; x++) {
 591		struct gfs2_bitmap *bi = rgd->rd_bits + x;
 592		kfree(bi->bi_clone);
 593		bi->bi_clone = NULL;
 594	}
 595}
 596
 597/**
 598 * gfs2_rsqa_alloc - make sure we have a reservation assigned to the inode
 599 *                 plus a quota allocations data structure, if necessary
 600 * @ip: the inode for this reservation
 601 */
 602int gfs2_rsqa_alloc(struct gfs2_inode *ip)
 603{
 604	return gfs2_qa_alloc(ip);
 605}
 606
 607static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs)
 608{
 609	gfs2_print_dbg(seq, "  B: n:%llu s:%llu b:%u f:%u\n",
 610		       (unsigned long long)rs->rs_inum,
 611		       (unsigned long long)gfs2_rbm_to_block(&rs->rs_rbm),
 612		       rs->rs_rbm.offset, rs->rs_free);
 613}
 614
 615/**
 616 * __rs_deltree - remove a multi-block reservation from the rgd tree
 617 * @rs: The reservation to remove
 618 *
 619 */
 620static void __rs_deltree(struct gfs2_blkreserv *rs)
 621{
 622	struct gfs2_rgrpd *rgd;
 623
 624	if (!gfs2_rs_active(rs))
 625		return;
 626
 627	rgd = rs->rs_rbm.rgd;
 628	trace_gfs2_rs(rs, TRACE_RS_TREEDEL);
 629	rb_erase(&rs->rs_node, &rgd->rd_rstree);
 630	RB_CLEAR_NODE(&rs->rs_node);
 631
 632	if (rs->rs_free) {
 633		struct gfs2_bitmap *bi = rbm_bi(&rs->rs_rbm);
 
 
 634
 635		/* return reserved blocks to the rgrp */
 636		BUG_ON(rs->rs_rbm.rgd->rd_reserved < rs->rs_free);
 637		rs->rs_rbm.rgd->rd_reserved -= rs->rs_free;
 638		/* The rgrp extent failure point is likely not to increase;
 639		   it will only do so if the freed blocks are somehow
 640		   contiguous with a span of free blocks that follows. Still,
 641		   it will force the number to be recalculated later. */
 642		rgd->rd_extfail_pt += rs->rs_free;
 643		rs->rs_free = 0;
 644		clear_bit(GBF_FULL, &bi->bi_flags);
 645	}
 646}
 647
 648/**
 649 * gfs2_rs_deltree - remove a multi-block reservation from the rgd tree
 650 * @rs: The reservation to remove
 651 *
 652 */
 653void gfs2_rs_deltree(struct gfs2_blkreserv *rs)
 654{
 655	struct gfs2_rgrpd *rgd;
 656
 657	rgd = rs->rs_rbm.rgd;
 658	if (rgd) {
 659		spin_lock(&rgd->rd_rsspin);
 660		__rs_deltree(rs);
 661		BUG_ON(rs->rs_free);
 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	up_write(&ip->i_rw_mutex);
 678	gfs2_qa_delete(ip, wcount);
 679}
 680
 681/**
 682 * return_all_reservations - return all reserved blocks back to the rgrp.
 683 * @rgd: the rgrp that needs its space back
 684 *
 685 * We previously reserved a bunch of blocks for allocation. Now we need to
 686 * give them back. This leave the reservation structures in tact, but removes
 687 * all of their corresponding "no-fly zones".
 688 */
 689static void return_all_reservations(struct gfs2_rgrpd *rgd)
 690{
 691	struct rb_node *n;
 692	struct gfs2_blkreserv *rs;
 693
 694	spin_lock(&rgd->rd_rsspin);
 695	while ((n = rb_first(&rgd->rd_rstree))) {
 696		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
 697		__rs_deltree(rs);
 698	}
 699	spin_unlock(&rgd->rd_rsspin);
 700}
 701
 702void gfs2_clear_rgrpd(struct gfs2_sbd *sdp)
 703{
 704	struct rb_node *n;
 705	struct gfs2_rgrpd *rgd;
 706	struct gfs2_glock *gl;
 707
 708	while ((n = rb_first(&sdp->sd_rindex_tree))) {
 709		rgd = rb_entry(n, struct gfs2_rgrpd, rd_node);
 710		gl = rgd->rd_gl;
 711
 712		rb_erase(n, &sdp->sd_rindex_tree);
 713
 714		if (gl) {
 715			spin_lock(&gl->gl_lockref.lock);
 716			gl->gl_object = NULL;
 717			spin_unlock(&gl->gl_lockref.lock);
 718			gfs2_glock_add_to_lru(gl);
 
 
 719			gfs2_glock_put(gl);
 720		}
 721
 722		gfs2_free_clones(rgd);
 
 723		kfree(rgd->rd_bits);
 724		rgd->rd_bits = NULL;
 725		return_all_reservations(rgd);
 726		kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 727	}
 728}
 729
 730static void gfs2_rindex_print(const struct gfs2_rgrpd *rgd)
 731{
 732	pr_info("ri_addr = %llu\n", (unsigned long long)rgd->rd_addr);
 733	pr_info("ri_length = %u\n", rgd->rd_length);
 734	pr_info("ri_data0 = %llu\n", (unsigned long long)rgd->rd_data0);
 735	pr_info("ri_data = %u\n", rgd->rd_data);
 736	pr_info("ri_bitbytes = %u\n", rgd->rd_bitbytes);
 737}
 738
 739/**
 740 * gfs2_compute_bitstructs - Compute the bitmap sizes
 741 * @rgd: The resource group descriptor
 742 *
 743 * Calculates bitmap descriptors, one for each block that contains bitmap data
 744 *
 745 * Returns: errno
 746 */
 747
 748static int compute_bitstructs(struct gfs2_rgrpd *rgd)
 749{
 750	struct gfs2_sbd *sdp = rgd->rd_sbd;
 751	struct gfs2_bitmap *bi;
 752	u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */
 753	u32 bytes_left, bytes;
 754	int x;
 755
 756	if (!length)
 757		return -EINVAL;
 758
 759	rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS);
 760	if (!rgd->rd_bits)
 761		return -ENOMEM;
 762
 763	bytes_left = rgd->rd_bitbytes;
 764
 765	for (x = 0; x < length; x++) {
 766		bi = rgd->rd_bits + x;
 767
 768		bi->bi_flags = 0;
 769		/* small rgrp; bitmap stored completely in header block */
 770		if (length == 1) {
 771			bytes = bytes_left;
 772			bi->bi_offset = sizeof(struct gfs2_rgrp);
 773			bi->bi_start = 0;
 774			bi->bi_len = bytes;
 775			bi->bi_blocks = bytes * GFS2_NBBY;
 776		/* header block */
 777		} else if (x == 0) {
 778			bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
 779			bi->bi_offset = sizeof(struct gfs2_rgrp);
 780			bi->bi_start = 0;
 781			bi->bi_len = bytes;
 782			bi->bi_blocks = bytes * GFS2_NBBY;
 783		/* last block */
 784		} else if (x + 1 == length) {
 785			bytes = bytes_left;
 786			bi->bi_offset = sizeof(struct gfs2_meta_header);
 787			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 788			bi->bi_len = bytes;
 789			bi->bi_blocks = bytes * GFS2_NBBY;
 790		/* other blocks */
 791		} else {
 792			bytes = sdp->sd_sb.sb_bsize -
 793				sizeof(struct gfs2_meta_header);
 794			bi->bi_offset = sizeof(struct gfs2_meta_header);
 795			bi->bi_start = rgd->rd_bitbytes - bytes_left;
 796			bi->bi_len = bytes;
 797			bi->bi_blocks = bytes * GFS2_NBBY;
 798		}
 799
 800		bytes_left -= bytes;
 801	}
 802
 803	if (bytes_left) {
 804		gfs2_consist_rgrpd(rgd);
 805		return -EIO;
 806	}
 807	bi = rgd->rd_bits + (length - 1);
 808	if ((bi->bi_start + bi->bi_len) * GFS2_NBBY != rgd->rd_data) {
 809		if (gfs2_consist_rgrpd(rgd)) {
 810			gfs2_rindex_print(rgd);
 811			fs_err(sdp, "start=%u len=%u offset=%u\n",
 812			       bi->bi_start, bi->bi_len, bi->bi_offset);
 813		}
 
 
 
 
 
 
 
 
 
 814		return -EIO;
 815	}
 816
 817	return 0;
 818}
 819
 820/**
 821 * gfs2_ri_total - Total up the file system space, according to the rindex.
 822 * @sdp: the filesystem
 823 *
 824 */
 825u64 gfs2_ri_total(struct gfs2_sbd *sdp)
 826{
 827	u64 total_data = 0;	
 828	struct inode *inode = sdp->sd_rindex;
 829	struct gfs2_inode *ip = GFS2_I(inode);
 830	char buf[sizeof(struct gfs2_rindex)];
 831	int error, rgrps;
 832
 833	for (rgrps = 0;; rgrps++) {
 834		loff_t pos = rgrps * sizeof(struct gfs2_rindex);
 835
 836		if (pos + sizeof(struct gfs2_rindex) > i_size_read(inode))
 837			break;
 838		error = gfs2_internal_read(ip, buf, &pos,
 839					   sizeof(struct gfs2_rindex));
 840		if (error != sizeof(struct gfs2_rindex))
 841			break;
 842		total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data);
 843	}
 844	return total_data;
 845}
 846
 847static int rgd_insert(struct gfs2_rgrpd *rgd)
 848{
 849	struct gfs2_sbd *sdp = rgd->rd_sbd;
 850	struct rb_node **newn = &sdp->sd_rindex_tree.rb_node, *parent = NULL;
 851
 852	/* Figure out where to put new node */
 853	while (*newn) {
 854		struct gfs2_rgrpd *cur = rb_entry(*newn, struct gfs2_rgrpd,
 855						  rd_node);
 856
 857		parent = *newn;
 858		if (rgd->rd_addr < cur->rd_addr)
 859			newn = &((*newn)->rb_left);
 860		else if (rgd->rd_addr > cur->rd_addr)
 861			newn = &((*newn)->rb_right);
 862		else
 863			return -EEXIST;
 864	}
 865
 866	rb_link_node(&rgd->rd_node, parent, newn);
 867	rb_insert_color(&rgd->rd_node, &sdp->sd_rindex_tree);
 868	sdp->sd_rgrps++;
 869	return 0;
 870}
 871
 872/**
 873 * read_rindex_entry - Pull in a new resource index entry from the disk
 874 * @ip: Pointer to the rindex inode
 875 *
 876 * Returns: 0 on success, > 0 on EOF, error code otherwise
 877 */
 878
 879static int read_rindex_entry(struct gfs2_inode *ip)
 880{
 881	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 882	const unsigned bsize = sdp->sd_sb.sb_bsize;
 883	loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
 884	struct gfs2_rindex buf;
 885	int error;
 886	struct gfs2_rgrpd *rgd;
 887
 888	if (pos >= i_size_read(&ip->i_inode))
 889		return 1;
 890
 891	error = gfs2_internal_read(ip, (char *)&buf, &pos,
 892				   sizeof(struct gfs2_rindex));
 893
 894	if (error != sizeof(struct gfs2_rindex))
 895		return (error == 0) ? 1 : error;
 896
 897	rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS);
 898	error = -ENOMEM;
 899	if (!rgd)
 900		return error;
 901
 902	rgd->rd_sbd = sdp;
 903	rgd->rd_addr = be64_to_cpu(buf.ri_addr);
 904	rgd->rd_length = be32_to_cpu(buf.ri_length);
 905	rgd->rd_data0 = be64_to_cpu(buf.ri_data0);
 906	rgd->rd_data = be32_to_cpu(buf.ri_data);
 907	rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes);
 908	spin_lock_init(&rgd->rd_rsspin);
 
 909
 910	error = compute_bitstructs(rgd);
 
 911	if (error)
 912		goto fail;
 913
 914	error = gfs2_glock_get(sdp, rgd->rd_addr,
 915			       &gfs2_rgrp_glops, CREATE, &rgd->rd_gl);
 916	if (error)
 917		goto fail;
 918
 919	rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr;
 920	rgd->rd_flags &= ~(GFS2_RDF_UPTODATE | GFS2_RDF_PREFERRED);
 921	if (rgd->rd_data > sdp->sd_max_rg_data)
 922		sdp->sd_max_rg_data = rgd->rd_data;
 923	spin_lock(&sdp->sd_rindex_spin);
 924	error = rgd_insert(rgd);
 925	spin_unlock(&sdp->sd_rindex_spin);
 926	if (!error) {
 927		rgd->rd_gl->gl_object = rgd;
 928		rgd->rd_gl->gl_vm.start = (rgd->rd_addr * bsize) & PAGE_MASK;
 929		rgd->rd_gl->gl_vm.end = PAGE_ALIGN((rgd->rd_addr +
 930						    rgd->rd_length) * bsize) - 1;
 931		return 0;
 932	}
 933
 934	error = 0; /* someone else read in the rgrp; free it and ignore it */
 
 935	gfs2_glock_put(rgd->rd_gl);
 936
 937fail:
 938	kfree(rgd->rd_bits);
 939	rgd->rd_bits = NULL;
 940	kmem_cache_free(gfs2_rgrpd_cachep, rgd);
 941	return error;
 942}
 943
 944/**
 945 * set_rgrp_preferences - Run all the rgrps, selecting some we prefer to use
 946 * @sdp: the GFS2 superblock
 947 *
 948 * The purpose of this function is to select a subset of the resource groups
 949 * and mark them as PREFERRED. We do it in such a way that each node prefers
 950 * to use a unique set of rgrps to minimize glock contention.
 951 */
 952static void set_rgrp_preferences(struct gfs2_sbd *sdp)
 953{
 954	struct gfs2_rgrpd *rgd, *first;
 955	int i;
 956
 957	/* Skip an initial number of rgrps, based on this node's journal ID.
 958	   That should start each node out on its own set. */
 959	rgd = gfs2_rgrpd_get_first(sdp);
 960	for (i = 0; i < sdp->sd_lockstruct.ls_jid; i++)
 961		rgd = gfs2_rgrpd_get_next(rgd);
 962	first = rgd;
 963
 964	do {
 965		rgd->rd_flags |= GFS2_RDF_PREFERRED;
 966		for (i = 0; i < sdp->sd_journals; i++) {
 967			rgd = gfs2_rgrpd_get_next(rgd);
 968			if (!rgd || rgd == first)
 969				break;
 970		}
 971	} while (rgd && rgd != first);
 972}
 973
 974/**
 975 * gfs2_ri_update - Pull in a new resource index from the disk
 976 * @ip: pointer to the rindex inode
 977 *
 978 * Returns: 0 on successful update, error code otherwise
 979 */
 980
 981static int gfs2_ri_update(struct gfs2_inode *ip)
 982{
 983	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 984	int error;
 985
 986	do {
 987		error = read_rindex_entry(ip);
 988	} while (error == 0);
 989
 990	if (error < 0)
 991		return error;
 992
 
 
 
 
 993	set_rgrp_preferences(sdp);
 994
 995	sdp->sd_rindex_uptodate = 1;
 996	return 0;
 997}
 998
 999/**
1000 * gfs2_rindex_update - Update the rindex if required
1001 * @sdp: The GFS2 superblock
1002 *
1003 * We grab a lock on the rindex inode to make sure that it doesn't
1004 * change whilst we are performing an operation. We keep this lock
1005 * for quite long periods of time compared to other locks. This
1006 * doesn't matter, since it is shared and it is very, very rarely
1007 * accessed in the exclusive mode (i.e. only when expanding the filesystem).
1008 *
1009 * This makes sure that we're using the latest copy of the resource index
1010 * special file, which might have been updated if someone expanded the
1011 * filesystem (via gfs2_grow utility), which adds new resource groups.
1012 *
1013 * Returns: 0 on succeess, error code otherwise
1014 */
1015
1016int gfs2_rindex_update(struct gfs2_sbd *sdp)
1017{
1018	struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
1019	struct gfs2_glock *gl = ip->i_gl;
1020	struct gfs2_holder ri_gh;
1021	int error = 0;
1022	int unlock_required = 0;
1023
1024	/* Read new copy from disk if we don't have the latest */
1025	if (!sdp->sd_rindex_uptodate) {
1026		if (!gfs2_glock_is_locked_by_me(gl)) {
1027			error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, &ri_gh);
1028			if (error)
1029				return error;
1030			unlock_required = 1;
1031		}
1032		if (!sdp->sd_rindex_uptodate)
1033			error = gfs2_ri_update(ip);
1034		if (unlock_required)
1035			gfs2_glock_dq_uninit(&ri_gh);
1036	}
1037
1038	return error;
1039}
1040
1041static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf)
1042{
1043	const struct gfs2_rgrp *str = buf;
1044	u32 rg_flags;
1045
1046	rg_flags = be32_to_cpu(str->rg_flags);
1047	rg_flags &= ~GFS2_RDF_MASK;
1048	rgd->rd_flags &= GFS2_RDF_MASK;
1049	rgd->rd_flags |= rg_flags;
1050	rgd->rd_free = be32_to_cpu(str->rg_free);
1051	rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes);
1052	rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration);
 
 
 
 
 
 
 
 
 
 
 
 
 
1053}
1054
1055static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf)
1056{
 
1057	struct gfs2_rgrp *str = buf;
 
1058
1059	str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK);
1060	str->rg_free = cpu_to_be32(rgd->rd_free);
1061	str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes);
1062	str->__pad = cpu_to_be32(0);
 
 
 
1063	str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration);
 
 
 
 
 
 
 
1064	memset(&str->rg_reserved, 0, sizeof(str->rg_reserved));
 
1065}
1066
1067static int gfs2_rgrp_lvb_valid(struct gfs2_rgrpd *rgd)
1068{
1069	struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1070	struct gfs2_rgrp *str = (struct gfs2_rgrp *)rgd->rd_bits[0].bi_bh->b_data;
 
 
1071
1072	if (rgl->rl_flags != str->rg_flags || rgl->rl_free != str->rg_free ||
1073	    rgl->rl_dinodes != str->rg_dinodes ||
1074	    rgl->rl_igeneration != str->rg_igeneration)
1075		return 0;
1076	return 1;
1077}
1078
1079static void gfs2_rgrp_ondisk2lvb(struct gfs2_rgrp_lvb *rgl, const void *buf)
1080{
1081	const struct gfs2_rgrp *str = buf;
1082
1083	rgl->rl_magic = cpu_to_be32(GFS2_MAGIC);
1084	rgl->rl_flags = str->rg_flags;
1085	rgl->rl_free = str->rg_free;
1086	rgl->rl_dinodes = str->rg_dinodes;
1087	rgl->rl_igeneration = str->rg_igeneration;
1088	rgl->__pad = 0UL;
1089}
1090
1091static void update_rgrp_lvb_unlinked(struct gfs2_rgrpd *rgd, u32 change)
1092{
1093	struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
1094	u32 unlinked = be32_to_cpu(rgl->rl_unlinked) + change;
1095	rgl->rl_unlinked = cpu_to_be32(unlinked);
 
 
 
1096}
1097
1098static u32 count_unlinked(struct gfs2_rgrpd *rgd)
1099{
1100	struct gfs2_bitmap *bi;
1101	const u32 length = rgd->rd_length;
1102	const u8 *buffer = NULL;
1103	u32 i, goal, count = 0;
1104
1105	for (i = 0, bi = rgd->rd_bits; i < length; i++, bi++) {
1106		goal = 0;
1107		buffer = bi->bi_bh->b_data + bi->bi_offset;
1108		WARN_ON(!buffer_uptodate(bi->bi_bh));
1109		while (goal < bi->bi_len * GFS2_NBBY) {
1110			goal = gfs2_bitfit(buffer, bi->bi_len, goal,
1111					   GFS2_BLKST_UNLINKED);
1112			if (goal == BFITNOENT)
1113				break;
1114			count++;
1115			goal++;
1116		}
1117	}
1118
1119	return count;
1120}
1121
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1122
1123/**
1124 * gfs2_rgrp_bh_get - Read in a RG's header and bitmaps
1125 * @rgd: the struct gfs2_rgrpd describing the RG to read in
1126 *
1127 * Read in all of a Resource Group's header and bitmap blocks.
1128 * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps.
1129 *
1130 * Returns: errno
1131 */
1132
1133static int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
1134{
 
1135	struct gfs2_sbd *sdp = rgd->rd_sbd;
1136	struct gfs2_glock *gl = rgd->rd_gl;
1137	unsigned int length = rgd->rd_length;
1138	struct gfs2_bitmap *bi;
1139	unsigned int x, y;
1140	int error;
1141
1142	if (rgd->rd_bits[0].bi_bh != NULL)
1143		return 0;
1144
1145	for (x = 0; x < length; x++) {
1146		bi = rgd->rd_bits + x;
1147		error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, 0, &bi->bi_bh);
1148		if (error)
1149			goto fail;
1150	}
1151
1152	for (y = length; y--;) {
1153		bi = rgd->rd_bits + y;
1154		error = gfs2_meta_wait(sdp, bi->bi_bh);
1155		if (error)
1156			goto fail;
1157		if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB :
1158					      GFS2_METATYPE_RG)) {
1159			error = -EIO;
1160			goto fail;
1161		}
1162	}
1163
1164	if (!(rgd->rd_flags & GFS2_RDF_UPTODATE)) {
1165		for (x = 0; x < length; x++)
1166			clear_bit(GBF_FULL, &rgd->rd_bits[x].bi_flags);
1167		gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
1168		rgd->rd_flags |= (GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1169		rgd->rd_free_clone = rgd->rd_free;
1170		/* max out the rgrp allocation failure point */
1171		rgd->rd_extfail_pt = rgd->rd_free;
1172	}
1173	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) {
1174		rgd->rd_rgl->rl_unlinked = cpu_to_be32(count_unlinked(rgd));
1175		gfs2_rgrp_ondisk2lvb(rgd->rd_rgl,
1176				     rgd->rd_bits[0].bi_bh->b_data);
1177	}
1178	else if (sdp->sd_args.ar_rgrplvb) {
1179		if (!gfs2_rgrp_lvb_valid(rgd)){
1180			gfs2_consist_rgrpd(rgd);
1181			error = -EIO;
1182			goto fail;
1183		}
1184		if (rgd->rd_rgl->rl_unlinked == 0)
1185			rgd->rd_flags &= ~GFS2_RDF_CHECK;
1186	}
1187	return 0;
1188
1189fail:
1190	while (x--) {
1191		bi = rgd->rd_bits + x;
1192		brelse(bi->bi_bh);
1193		bi->bi_bh = NULL;
1194		gfs2_assert_warn(sdp, !bi->bi_clone);
1195	}
1196
1197	return error;
1198}
1199
1200static int update_rgrp_lvb(struct gfs2_rgrpd *rgd)
1201{
1202	u32 rl_flags;
1203
1204	if (rgd->rd_flags & GFS2_RDF_UPTODATE)
1205		return 0;
1206
1207	if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic)
1208		return gfs2_rgrp_bh_get(rgd);
1209
1210	rl_flags = be32_to_cpu(rgd->rd_rgl->rl_flags);
1211	rl_flags &= ~GFS2_RDF_MASK;
1212	rgd->rd_flags &= GFS2_RDF_MASK;
1213	rgd->rd_flags |= (rl_flags | GFS2_RDF_UPTODATE | GFS2_RDF_CHECK);
1214	if (rgd->rd_rgl->rl_unlinked == 0)
1215		rgd->rd_flags &= ~GFS2_RDF_CHECK;
1216	rgd->rd_free = be32_to_cpu(rgd->rd_rgl->rl_free);
 
1217	rgd->rd_free_clone = rgd->rd_free;
 
 
 
1218	rgd->rd_dinodes = be32_to_cpu(rgd->rd_rgl->rl_dinodes);
1219	rgd->rd_igeneration = be64_to_cpu(rgd->rd_rgl->rl_igeneration);
1220	return 0;
1221}
1222
1223int gfs2_rgrp_go_lock(struct gfs2_holder *gh)
1224{
1225	struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1226	struct gfs2_sbd *sdp = rgd->rd_sbd;
1227
1228	if (gh->gh_flags & GL_SKIP && sdp->sd_args.ar_rgrplvb)
1229		return 0;
1230	return gfs2_rgrp_bh_get(rgd);
1231}
1232
1233/**
1234 * gfs2_rgrp_brelse - Release RG bitmaps read in with gfs2_rgrp_bh_get()
1235 * @rgd: The resource group
1236 *
1237 */
1238
1239void gfs2_rgrp_brelse(struct gfs2_rgrpd *rgd)
1240{
1241	int x, length = rgd->rd_length;
1242
1243	for (x = 0; x < length; x++) {
1244		struct gfs2_bitmap *bi = rgd->rd_bits + x;
1245		if (bi->bi_bh) {
1246			brelse(bi->bi_bh);
1247			bi->bi_bh = NULL;
1248		}
1249	}
1250
1251}
1252
1253/**
1254 * gfs2_rgrp_go_unlock - Unlock a rgrp glock
1255 * @gh: The glock holder for the resource group
1256 *
1257 */
1258
1259void gfs2_rgrp_go_unlock(struct gfs2_holder *gh)
1260{
1261	struct gfs2_rgrpd *rgd = gh->gh_gl->gl_object;
1262	int demote_requested = test_bit(GLF_DEMOTE, &gh->gh_gl->gl_flags) |
1263		test_bit(GLF_PENDING_DEMOTE, &gh->gh_gl->gl_flags);
1264
1265	if (rgd && demote_requested)
1266		gfs2_rgrp_brelse(rgd);
1267}
1268
1269int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
1270			     struct buffer_head *bh,
1271			     const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed)
1272{
1273	struct super_block *sb = sdp->sd_vfs;
1274	u64 blk;
1275	sector_t start = 0;
1276	sector_t nr_blks = 0;
1277	int rv;
1278	unsigned int x;
1279	u32 trimmed = 0;
1280	u8 diff;
1281
1282	for (x = 0; x < bi->bi_len; x++) {
1283		const u8 *clone = bi->bi_clone ? bi->bi_clone : bi->bi_bh->b_data;
1284		clone += bi->bi_offset;
1285		clone += x;
1286		if (bh) {
1287			const u8 *orig = bh->b_data + bi->bi_offset + x;
1288			diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1));
1289		} else {
1290			diff = ~(*clone | (*clone >> 1));
1291		}
1292		diff &= 0x55;
1293		if (diff == 0)
1294			continue;
1295		blk = offset + ((bi->bi_start + x) * GFS2_NBBY);
1296		while(diff) {
1297			if (diff & 1) {
1298				if (nr_blks == 0)
1299					goto start_new_extent;
1300				if ((start + nr_blks) != blk) {
1301					if (nr_blks >= minlen) {
1302						rv = sb_issue_discard(sb,
1303							start, nr_blks,
1304							GFP_NOFS, 0);
1305						if (rv)
1306							goto fail;
1307						trimmed += nr_blks;
1308					}
1309					nr_blks = 0;
1310start_new_extent:
1311					start = blk;
1312				}
1313				nr_blks++;
1314			}
1315			diff >>= 2;
1316			blk++;
1317		}
1318	}
1319	if (nr_blks >= minlen) {
1320		rv = sb_issue_discard(sb, start, nr_blks, GFP_NOFS, 0);
1321		if (rv)
1322			goto fail;
1323		trimmed += nr_blks;
1324	}
1325	if (ptrimmed)
1326		*ptrimmed = trimmed;
1327	return 0;
1328
1329fail:
1330	if (sdp->sd_args.ar_discard)
1331		fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem", rv);
1332	sdp->sd_args.ar_discard = 0;
1333	return -EIO;
1334}
1335
1336/**
1337 * gfs2_fitrim - Generate discard requests for unused bits of the filesystem
1338 * @filp: Any file on the filesystem
1339 * @argp: Pointer to the arguments (also used to pass result)
1340 *
1341 * Returns: 0 on success, otherwise error code
1342 */
1343
1344int gfs2_fitrim(struct file *filp, void __user *argp)
1345{
1346	struct inode *inode = file_inode(filp);
1347	struct gfs2_sbd *sdp = GFS2_SB(inode);
1348	struct request_queue *q = bdev_get_queue(sdp->sd_vfs->s_bdev);
1349	struct buffer_head *bh;
1350	struct gfs2_rgrpd *rgd;
1351	struct gfs2_rgrpd *rgd_end;
1352	struct gfs2_holder gh;
1353	struct fstrim_range r;
1354	int ret = 0;
1355	u64 amt;
1356	u64 trimmed = 0;
1357	u64 start, end, minlen;
1358	unsigned int x;
1359	unsigned bs_shift = sdp->sd_sb.sb_bsize_shift;
1360
1361	if (!capable(CAP_SYS_ADMIN))
1362		return -EPERM;
1363
1364	if (!blk_queue_discard(q))
 
 
 
1365		return -EOPNOTSUPP;
1366
1367	if (copy_from_user(&r, argp, sizeof(r)))
1368		return -EFAULT;
1369
1370	ret = gfs2_rindex_update(sdp);
1371	if (ret)
1372		return ret;
1373
1374	start = r.start >> bs_shift;
1375	end = start + (r.len >> bs_shift);
1376	minlen = max_t(u64, r.minlen,
1377		       q->limits.discard_granularity) >> bs_shift;
1378
1379	if (end <= start || minlen > sdp->sd_max_rg_data)
1380		return -EINVAL;
1381
1382	rgd = gfs2_blk2rgrpd(sdp, start, 0);
1383	rgd_end = gfs2_blk2rgrpd(sdp, end, 0);
1384
1385	if ((gfs2_rgrpd_get_first(sdp) == gfs2_rgrpd_get_next(rgd_end))
1386	    && (start > rgd_end->rd_data0 + rgd_end->rd_data))
1387		return -EINVAL; /* start is beyond the end of the fs */
1388
1389	while (1) {
1390
1391		ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
 
1392		if (ret)
1393			goto out;
1394
1395		if (!(rgd->rd_flags & GFS2_RGF_TRIMMED)) {
1396			/* Trim each bitmap in the rgrp */
1397			for (x = 0; x < rgd->rd_length; x++) {
1398				struct gfs2_bitmap *bi = rgd->rd_bits + x;
 
1399				ret = gfs2_rgrp_send_discards(sdp,
1400						rgd->rd_data0, NULL, bi, minlen,
1401						&amt);
 
1402				if (ret) {
1403					gfs2_glock_dq_uninit(&gh);
1404					goto out;
1405				}
1406				trimmed += amt;
1407			}
1408
1409			/* Mark rgrp as having been trimmed */
1410			ret = gfs2_trans_begin(sdp, RES_RG_HDR, 0);
1411			if (ret == 0) {
1412				bh = rgd->rd_bits[0].bi_bh;
 
1413				rgd->rd_flags |= GFS2_RGF_TRIMMED;
1414				gfs2_trans_add_meta(rgd->rd_gl, bh);
1415				gfs2_rgrp_out(rgd, bh->b_data);
1416				gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, bh->b_data);
1417				gfs2_trans_end(sdp);
1418			}
1419		}
1420		gfs2_glock_dq_uninit(&gh);
1421
1422		if (rgd == rgd_end)
1423			break;
1424
1425		rgd = gfs2_rgrpd_get_next(rgd);
1426	}
1427
1428out:
1429	r.len = trimmed << bs_shift;
1430	if (copy_to_user(argp, &r, sizeof(r)))
1431		return -EFAULT;
1432
1433	return ret;
1434}
1435
1436/**
1437 * rs_insert - insert a new multi-block reservation into the rgrp's rb_tree
1438 * @ip: the inode structure
1439 *
1440 */
1441static void rs_insert(struct gfs2_inode *ip)
1442{
1443	struct rb_node **newn, *parent = NULL;
1444	int rc;
1445	struct gfs2_blkreserv *rs = &ip->i_res;
1446	struct gfs2_rgrpd *rgd = rs->rs_rbm.rgd;
1447	u64 fsblock = gfs2_rbm_to_block(&rs->rs_rbm);
1448
1449	BUG_ON(gfs2_rs_active(rs));
1450
1451	spin_lock(&rgd->rd_rsspin);
1452	newn = &rgd->rd_rstree.rb_node;
1453	while (*newn) {
1454		struct gfs2_blkreserv *cur =
1455			rb_entry(*newn, struct gfs2_blkreserv, rs_node);
1456
1457		parent = *newn;
1458		rc = rs_cmp(fsblock, rs->rs_free, cur);
1459		if (rc > 0)
1460			newn = &((*newn)->rb_right);
1461		else if (rc < 0)
1462			newn = &((*newn)->rb_left);
1463		else {
1464			spin_unlock(&rgd->rd_rsspin);
1465			WARN_ON(1);
1466			return;
1467		}
1468	}
1469
1470	rb_link_node(&rs->rs_node, parent, newn);
1471	rb_insert_color(&rs->rs_node, &rgd->rd_rstree);
1472
1473	/* Do our rgrp accounting for the reservation */
1474	rgd->rd_reserved += rs->rs_free; /* blocks reserved */
1475	spin_unlock(&rgd->rd_rsspin);
1476	trace_gfs2_rs(rs, TRACE_RS_INSERT);
1477}
1478
1479/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1480 * rg_mblk_search - find a group of multiple free blocks to form a reservation
1481 * @rgd: the resource group descriptor
1482 * @ip: pointer to the inode for which we're reserving blocks
1483 * @ap: the allocation parameters
1484 *
1485 */
1486
1487static void rg_mblk_search(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip,
1488			   const struct gfs2_alloc_parms *ap)
1489{
1490	struct gfs2_rbm rbm = { .rgd = rgd, };
1491	u64 goal;
1492	struct gfs2_blkreserv *rs = &ip->i_res;
1493	u32 extlen;
1494	u32 free_blocks = rgd->rd_free_clone - rgd->rd_reserved;
1495	int ret;
1496	struct inode *inode = &ip->i_inode;
1497
 
 
 
 
 
 
 
 
 
1498	if (S_ISDIR(inode->i_mode))
1499		extlen = 1;
1500	else {
1501		extlen = max_t(u32, atomic_read(&rs->rs_sizehint), ap->target);
1502		extlen = clamp(extlen, RGRP_RSRV_MINBLKS, free_blocks);
1503	}
1504	if ((rgd->rd_free_clone < rgd->rd_reserved) || (free_blocks < extlen))
1505		return;
1506
1507	/* Find bitmap block that contains bits for goal block */
1508	if (rgrp_contains_block(rgd, ip->i_goal))
1509		goal = ip->i_goal;
1510	else
1511		goal = rgd->rd_last_alloc + rgd->rd_data0;
1512
1513	if (WARN_ON(gfs2_rbm_from_block(&rbm, goal)))
1514		return;
1515
1516	ret = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &extlen, ip, true);
1517	if (ret == 0) {
1518		rs->rs_rbm = rbm;
1519		rs->rs_free = extlen;
1520		rs->rs_inum = ip->i_no_addr;
1521		rs_insert(ip);
1522	} else {
1523		if (goal == rgd->rd_last_alloc + rgd->rd_data0)
1524			rgd->rd_last_alloc = 0;
1525	}
1526}
1527
1528/**
1529 * gfs2_next_unreserved_block - Return next block that is not reserved
1530 * @rgd: The resource group
1531 * @block: The starting block
1532 * @length: The required length
1533 * @ip: Ignore any reservations for this inode
1534 *
1535 * If the block does not appear in any reservation, then return the
1536 * block number unchanged. If it does appear in the reservation, then
1537 * keep looking through the tree of reservations in order to find the
1538 * first block number which is not reserved.
1539 */
1540
1541static u64 gfs2_next_unreserved_block(struct gfs2_rgrpd *rgd, u64 block,
1542				      u32 length,
1543				      const struct gfs2_inode *ip)
1544{
1545	struct gfs2_blkreserv *rs;
1546	struct rb_node *n;
1547	int rc;
1548
1549	spin_lock(&rgd->rd_rsspin);
1550	n = rgd->rd_rstree.rb_node;
1551	while (n) {
1552		rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1553		rc = rs_cmp(block, length, rs);
1554		if (rc < 0)
1555			n = n->rb_left;
1556		else if (rc > 0)
1557			n = n->rb_right;
1558		else
1559			break;
1560	}
1561
1562	if (n) {
1563		while ((rs_cmp(block, length, rs) == 0) && (&ip->i_res != rs)) {
1564			block = gfs2_rbm_to_block(&rs->rs_rbm) + rs->rs_free;
1565			n = n->rb_right;
1566			if (n == NULL)
1567				break;
1568			rs = rb_entry(n, struct gfs2_blkreserv, rs_node);
1569		}
1570	}
1571
1572	spin_unlock(&rgd->rd_rsspin);
1573	return block;
1574}
1575
1576/**
1577 * gfs2_reservation_check_and_update - Check for reservations during block alloc
1578 * @rbm: The current position in the resource group
1579 * @ip: The inode for which we are searching for blocks
1580 * @minext: The minimum extent length
1581 * @maxext: A pointer to the maximum extent structure
1582 *
1583 * This checks the current position in the rgrp to see whether there is
1584 * a reservation covering this block. If not then this function is a
1585 * no-op. If there is, then the position is moved to the end of the
1586 * contiguous reservation(s) so that we are pointing at the first
1587 * non-reserved block.
1588 *
1589 * Returns: 0 if no reservation, 1 if @rbm has changed, otherwise an error
1590 */
1591
1592static int gfs2_reservation_check_and_update(struct gfs2_rbm *rbm,
1593					     const struct gfs2_inode *ip,
1594					     u32 minext,
1595					     struct gfs2_extent *maxext)
1596{
1597	u64 block = gfs2_rbm_to_block(rbm);
1598	u32 extlen = 1;
1599	u64 nblock;
1600	int ret;
1601
1602	/*
1603	 * If we have a minimum extent length, then skip over any extent
1604	 * which is less than the min extent length in size.
1605	 */
1606	if (minext) {
1607		extlen = gfs2_free_extlen(rbm, minext);
1608		if (extlen <= maxext->len)
1609			goto fail;
1610	}
1611
1612	/*
1613	 * Check the extent which has been found against the reservations
1614	 * and skip if parts of it are already reserved
1615	 */
1616	nblock = gfs2_next_unreserved_block(rbm->rgd, block, extlen, ip);
1617	if (nblock == block) {
1618		if (!minext || extlen >= minext)
1619			return 0;
1620
1621		if (extlen > maxext->len) {
1622			maxext->len = extlen;
1623			maxext->rbm = *rbm;
1624		}
 
 
 
 
 
 
1625fail:
1626		nblock = block + extlen;
1627	}
1628	ret = gfs2_rbm_from_block(rbm, nblock);
1629	if (ret < 0)
1630		return ret;
1631	return 1;
1632}
1633
1634/**
1635 * gfs2_rbm_find - Look for blocks of a particular state
1636 * @rbm: Value/result starting position and final position
1637 * @state: The state which we want to find
1638 * @minext: Pointer to the requested extent length (NULL for a single block)
1639 *          This is updated to be the actual reservation size.
1640 * @ip: If set, check for reservations
1641 * @nowrap: Stop looking at the end of the rgrp, rather than wrapping
1642 *          around until we've reached the starting point.
1643 *
1644 * Side effects:
1645 * - If looking for free blocks, we set GBF_FULL on each bitmap which
1646 *   has no free blocks in it.
1647 * - If looking for free blocks, we set rd_extfail_pt on each rgrp which
1648 *   has come up short on a free block search.
1649 *
1650 * Returns: 0 on success, -ENOSPC if there is no block of the requested state
1651 */
1652
1653static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
1654			 const struct gfs2_inode *ip, bool nowrap)
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);
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 (gfs2_holder_initialized(&rs->rs_rgd_gh))
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);
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	}
2338
2339	/* Since all blocks are reserved in advance, this shouldn't happen */
2340	if (error) {
2341		fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d fail_pt=%d\n",
2342			(unsigned long long)ip->i_no_addr, error, *nblocks,
2343			test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags),
2344			rbm.rgd->rd_extfail_pt);
2345		goto rgrp_error;
2346	}
2347
2348	gfs2_alloc_extent(&rbm, dinode, nblocks);
2349	block = gfs2_rbm_to_block(&rbm);
2350	rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0;
2351	if (gfs2_rs_active(&ip->i_res))
2352		gfs2_adjust_reservation(ip, &rbm, *nblocks);
2353	ndata = *nblocks;
2354	if (dinode)
2355		ndata--;
2356
2357	if (!dinode) {
2358		ip->i_goal = block + ndata - 1;
2359		error = gfs2_meta_inode_buffer(ip, &dibh);
2360		if (error == 0) {
2361			struct gfs2_dinode *di =
2362				(struct gfs2_dinode *)dibh->b_data;
2363			gfs2_trans_add_meta(ip->i_gl, dibh);
2364			di->di_goal_meta = di->di_goal_data =
2365				cpu_to_be64(ip->i_goal);
2366			brelse(dibh);
2367		}
2368	}
2369	if (rbm.rgd->rd_free < *nblocks) {
2370		pr_warn("nblocks=%u\n", *nblocks);
 
 
 
2371		goto rgrp_error;
2372	}
2373
 
 
 
 
2374	rbm.rgd->rd_free -= *nblocks;
 
2375	if (dinode) {
2376		rbm.rgd->rd_dinodes++;
2377		*generation = rbm.rgd->rd_igeneration++;
2378		if (*generation == 0)
2379			*generation = rbm.rgd->rd_igeneration++;
2380	}
2381
2382	gfs2_trans_add_meta(rbm.rgd->rd_gl, rbm.rgd->rd_bits[0].bi_bh);
2383	gfs2_rgrp_out(rbm.rgd, rbm.rgd->rd_bits[0].bi_bh->b_data);
2384	gfs2_rgrp_ondisk2lvb(rbm.rgd->rd_rgl, rbm.rgd->rd_bits[0].bi_bh->b_data);
2385
2386	gfs2_statfs_change(sdp, 0, -(s64)*nblocks, dinode ? 1 : 0);
2387	if (dinode)
2388		gfs2_trans_add_unrevoke(sdp, block, *nblocks);
2389
2390	gfs2_quota_change(ip, *nblocks, ip->i_inode.i_uid, ip->i_inode.i_gid);
2391
2392	rbm.rgd->rd_free_clone -= *nblocks;
2393	trace_gfs2_block_alloc(ip, rbm.rgd, block, *nblocks,
2394			       dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
2395	*bn = block;
2396	return 0;
2397
2398rgrp_error:
 
2399	gfs2_rgrp_error(rbm.rgd);
2400	return -EIO;
2401}
2402
2403/**
2404 * __gfs2_free_blocks - free a contiguous run of block(s)
2405 * @ip: the inode these blocks are being freed from
 
2406 * @bstart: first block of a run of contiguous blocks
2407 * @blen: the length of the block run
2408 * @meta: 1 if the blocks represent metadata
2409 *
2410 */
2411
2412void __gfs2_free_blocks(struct gfs2_inode *ip, u64 bstart, u32 blen, int meta)
 
2413{
2414	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2415	struct gfs2_rgrpd *rgd;
2416
2417	rgd = rgblk_free(sdp, bstart, blen, GFS2_BLKST_FREE);
2418	if (!rgd)
2419		return;
2420	trace_gfs2_block_alloc(ip, rgd, bstart, blen, GFS2_BLKST_FREE);
2421	rgd->rd_free += blen;
2422	rgd->rd_flags &= ~GFS2_RGF_TRIMMED;
2423	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2424	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2425	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2426
2427	/* Directories keep their data in the metadata address space */
2428	if (meta || ip->i_depth)
2429		gfs2_meta_wipe(ip, bstart, blen);
2430}
2431
2432/**
2433 * gfs2_free_meta - free a contiguous run of data block(s)
2434 * @ip: the inode these blocks are being freed from
 
2435 * @bstart: first block of a run of contiguous blocks
2436 * @blen: the length of the block run
2437 *
2438 */
2439
2440void gfs2_free_meta(struct gfs2_inode *ip, u64 bstart, u32 blen)
 
2441{
2442	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2443
2444	__gfs2_free_blocks(ip, bstart, blen, 1);
2445	gfs2_statfs_change(sdp, 0, +blen, 0);
2446	gfs2_quota_change(ip, -(s64)blen, ip->i_inode.i_uid, ip->i_inode.i_gid);
2447}
2448
2449void gfs2_unlink_di(struct inode *inode)
2450{
2451	struct gfs2_inode *ip = GFS2_I(inode);
2452	struct gfs2_sbd *sdp = GFS2_SB(inode);
2453	struct gfs2_rgrpd *rgd;
2454	u64 blkno = ip->i_no_addr;
2455
2456	rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_UNLINKED);
2457	if (!rgd)
2458		return;
 
 
2459	trace_gfs2_block_alloc(ip, rgd, blkno, 1, GFS2_BLKST_UNLINKED);
2460	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2461	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2462	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2463	update_rgrp_lvb_unlinked(rgd, 1);
2464}
2465
2466static void gfs2_free_uninit_di(struct gfs2_rgrpd *rgd, u64 blkno)
2467{
2468	struct gfs2_sbd *sdp = rgd->rd_sbd;
2469	struct gfs2_rgrpd *tmp_rgd;
2470
2471	tmp_rgd = rgblk_free(sdp, blkno, 1, GFS2_BLKST_FREE);
2472	if (!tmp_rgd)
2473		return;
2474	gfs2_assert_withdraw(sdp, rgd == tmp_rgd);
2475
 
 
2476	if (!rgd->rd_dinodes)
2477		gfs2_consist_rgrpd(rgd);
2478	rgd->rd_dinodes--;
2479	rgd->rd_free++;
2480
2481	gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh);
2482	gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data);
2483	gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, rgd->rd_bits[0].bi_bh->b_data);
2484	update_rgrp_lvb_unlinked(rgd, -1);
2485
2486	gfs2_statfs_change(sdp, 0, +1, -1);
2487}
2488
2489
2490void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip)
2491{
2492	gfs2_free_uninit_di(rgd, ip->i_no_addr);
2493	trace_gfs2_block_alloc(ip, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE);
2494	gfs2_quota_change(ip, -1, ip->i_inode.i_uid, ip->i_inode.i_gid);
2495	gfs2_meta_wipe(ip, ip->i_no_addr, 1);
2496}
2497
2498/**
2499 * gfs2_check_blk_type - Check the type of a block
2500 * @sdp: The superblock
2501 * @no_addr: The block number to check
2502 * @type: The block type we are looking for
2503 *
 
 
 
 
2504 * Returns: 0 if the block type matches the expected type
2505 *          -ESTALE if it doesn't match
2506 *          or -ve errno if something went wrong while checking
2507 */
2508
2509int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
2510{
2511	struct gfs2_rgrpd *rgd;
2512	struct gfs2_holder rgd_gh;
 
2513	int error = -EINVAL;
2514
2515	rgd = gfs2_blk2rgrpd(sdp, no_addr, 1);
2516	if (!rgd)
2517		goto fail;
2518
2519	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
2520	if (error)
2521		goto fail;
2522
2523	if (gfs2_get_block_type(rgd, no_addr) != type)
2524		error = -ESTALE;
 
 
 
 
 
 
 
 
 
 
 
2525
2526	gfs2_glock_dq_uninit(&rgd_gh);
 
2527fail:
2528	return error;
2529}
2530
2531/**
2532 * gfs2_rlist_add - add a RG to a list of RGs
2533 * @ip: the inode
2534 * @rlist: the list of resource groups
2535 * @block: the block
2536 *
2537 * Figure out what RG a block belongs to and add that RG to the list
2538 *
2539 * FIXME: Don't use NOFAIL
2540 *
2541 */
2542
2543void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
2544		    u64 block)
2545{
2546	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2547	struct gfs2_rgrpd *rgd;
2548	struct gfs2_rgrpd **tmp;
2549	unsigned int new_space;
2550	unsigned int x;
2551
2552	if (gfs2_assert_warn(sdp, !rlist->rl_ghs))
2553		return;
2554
2555	if (ip->i_rgd && rgrp_contains_block(ip->i_rgd, block))
2556		rgd = ip->i_rgd;
2557	else
 
 
 
 
 
2558		rgd = gfs2_blk2rgrpd(sdp, block, 1);
 
 
 
 
 
 
2559	if (!rgd) {
2560		fs_err(sdp, "rlist_add: no rgrp for block %llu\n", (unsigned long long)block);
 
2561		return;
2562	}
2563	ip->i_rgd = rgd;
2564
2565	for (x = 0; x < rlist->rl_rgrps; x++)
2566		if (rlist->rl_rgd[x] == rgd)
 
 
2567			return;
 
 
2568
2569	if (rlist->rl_rgrps == rlist->rl_space) {
2570		new_space = rlist->rl_space + 10;
2571
2572		tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *),
2573			      GFP_NOFS | __GFP_NOFAIL);
2574
2575		if (rlist->rl_rgd) {
2576			memcpy(tmp, rlist->rl_rgd,
2577			       rlist->rl_space * sizeof(struct gfs2_rgrpd *));
2578			kfree(rlist->rl_rgd);
2579		}
2580
2581		rlist->rl_space = new_space;
2582		rlist->rl_rgd = tmp;
2583	}
2584
2585	rlist->rl_rgd[rlist->rl_rgrps++] = rgd;
2586}
2587
2588/**
2589 * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate
2590 *      and initialize an array of glock holders for them
2591 * @rlist: the list of resource groups
2592 * @state: the lock state to acquire the RG lock in
 
2593 *
2594 * FIXME: Don't use NOFAIL
2595 *
2596 */
2597
2598void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state)
 
2599{
2600	unsigned int x;
2601
2602	rlist->rl_ghs = kmalloc(rlist->rl_rgrps * sizeof(struct gfs2_holder),
2603				GFP_NOFS | __GFP_NOFAIL);
 
2604	for (x = 0; x < rlist->rl_rgrps; x++)
2605		gfs2_holder_init(rlist->rl_rgd[x]->rd_gl,
2606				state, 0,
2607				&rlist->rl_ghs[x]);
2608}
2609
2610/**
2611 * gfs2_rlist_free - free a resource group list
2612 * @rlist: the list of resource groups
2613 *
2614 */
2615
2616void gfs2_rlist_free(struct gfs2_rgrp_list *rlist)
2617{
2618	unsigned int x;
2619
2620	kfree(rlist->rl_rgd);
2621
2622	if (rlist->rl_ghs) {
2623		for (x = 0; x < rlist->rl_rgrps; x++)
2624			gfs2_holder_uninit(&rlist->rl_ghs[x]);
2625		kfree(rlist->rl_ghs);
2626		rlist->rl_ghs = NULL;
2627	}
2628}
2629