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v3.1
 
   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2006 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#include <linux/slab.h>
  11#include <linux/spinlock.h>
 
  12#include <linux/completion.h>
  13#include <linux/buffer_head.h>
  14#include <linux/pagemap.h>
  15#include <linux/uio.h>
  16#include <linux/blkdev.h>
  17#include <linux/mm.h>
  18#include <linux/mount.h>
  19#include <linux/fs.h>
 
  20#include <linux/gfs2_ondisk.h>
  21#include <linux/ext2_fs.h>
  22#include <linux/falloc.h>
  23#include <linux/swap.h>
  24#include <linux/crc32.h>
  25#include <linux/writeback.h>
  26#include <asm/uaccess.h>
  27#include <linux/dlm.h>
  28#include <linux/dlm_plock.h>
 
 
 
  29
  30#include "gfs2.h"
  31#include "incore.h"
  32#include "bmap.h"
 
  33#include "dir.h"
  34#include "glock.h"
  35#include "glops.h"
  36#include "inode.h"
  37#include "log.h"
  38#include "meta_io.h"
  39#include "quota.h"
  40#include "rgrp.h"
  41#include "trans.h"
  42#include "util.h"
  43
  44/**
  45 * gfs2_llseek - seek to a location in a file
  46 * @file: the file
  47 * @offset: the offset
  48 * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
  49 *
  50 * SEEK_END requires the glock for the file because it references the
  51 * file's size.
  52 *
  53 * Returns: The new offset, or errno
  54 */
  55
  56static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
  57{
  58	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
  59	struct gfs2_holder i_gh;
  60	loff_t error;
  61
  62	if (origin == 2) {
 
  63		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
  64					   &i_gh);
  65		if (!error) {
  66			error = generic_file_llseek_unlocked(file, offset, origin);
  67			gfs2_glock_dq_uninit(&i_gh);
  68		}
  69	} else
  70		error = generic_file_llseek_unlocked(file, offset, origin);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  71
  72	return error;
  73}
  74
  75/**
  76 * gfs2_readdir - Read directory entries from a directory
  77 * @file: The directory to read from
  78 * @dirent: Buffer for dirents
  79 * @filldir: Function used to do the copying
  80 *
  81 * Returns: errno
  82 */
  83
  84static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
  85{
  86	struct inode *dir = file->f_mapping->host;
  87	struct gfs2_inode *dip = GFS2_I(dir);
  88	struct gfs2_holder d_gh;
  89	u64 offset = file->f_pos;
  90	int error;
  91
  92	gfs2_holder_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
  93	error = gfs2_glock_nq(&d_gh);
  94	if (error) {
  95		gfs2_holder_uninit(&d_gh);
  96		return error;
  97	}
  98
  99	error = gfs2_dir_read(dir, &offset, dirent, filldir);
 100
 101	gfs2_glock_dq_uninit(&d_gh);
 102
 103	file->f_pos = offset;
 104
 105	return error;
 106}
 107
 108/**
 109 * fsflags_cvt
 110 * @table: A table of 32 u32 flags
 111 * @val: a 32 bit value to convert
 112 *
 113 * This function can be used to convert between fsflags values and
 114 * GFS2's own flags values.
 115 *
 116 * Returns: the converted flags
 
 117 */
 118static u32 fsflags_cvt(const u32 *table, u32 val)
 119{
 120	u32 res = 0;
 121	while(val) {
 122		if (val & 1)
 123			res |= *table;
 124		table++;
 125		val >>= 1;
 126	}
 127	return res;
 128}
 129
 130static const u32 fsflags_to_gfs2[32] = {
 131	[3] = GFS2_DIF_SYNC,
 132	[4] = GFS2_DIF_IMMUTABLE,
 133	[5] = GFS2_DIF_APPENDONLY,
 134	[7] = GFS2_DIF_NOATIME,
 135	[12] = GFS2_DIF_EXHASH,
 136	[14] = GFS2_DIF_INHERIT_JDATA,
 137};
 138
 139static const u32 gfs2_to_fsflags[32] = {
 140	[gfs2fl_Sync] = FS_SYNC_FL,
 141	[gfs2fl_Immutable] = FS_IMMUTABLE_FL,
 142	[gfs2fl_AppendOnly] = FS_APPEND_FL,
 143	[gfs2fl_NoAtime] = FS_NOATIME_FL,
 144	[gfs2fl_ExHash] = FS_INDEX_FL,
 145	[gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
 146};
 147
 148static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
 
 
 
 
 
 
 
 
 
 
 
 149{
 150	struct inode *inode = filp->f_path.dentry->d_inode;
 151	struct gfs2_inode *ip = GFS2_I(inode);
 152	struct gfs2_holder gh;
 153	int error;
 154	u32 fsflags;
 155
 
 
 
 156	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 157	error = gfs2_glock_nq(&gh);
 158	if (error)
 159		return error;
 160
 161	fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags);
 162	if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA)
 163		fsflags |= FS_JOURNAL_DATA_FL;
 164	if (put_user(fsflags, ptr))
 165		error = -EFAULT;
 166
 167	gfs2_glock_dq(&gh);
 
 168	gfs2_holder_uninit(&gh);
 169	return error;
 170}
 171
 172void gfs2_set_inode_flags(struct inode *inode)
 173{
 174	struct gfs2_inode *ip = GFS2_I(inode);
 175	unsigned int flags = inode->i_flags;
 176
 177	flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
 178	if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
 179		inode->i_flags |= S_NOSEC;
 180	if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
 181		flags |= S_IMMUTABLE;
 182	if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
 183		flags |= S_APPEND;
 184	if (ip->i_diskflags & GFS2_DIF_NOATIME)
 185		flags |= S_NOATIME;
 186	if (ip->i_diskflags & GFS2_DIF_SYNC)
 187		flags |= S_SYNC;
 188	inode->i_flags = flags;
 189}
 190
 191/* Flags that can be set by user space */
 192#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA|			\
 193			     GFS2_DIF_IMMUTABLE|		\
 194			     GFS2_DIF_APPENDONLY|		\
 195			     GFS2_DIF_NOATIME|			\
 196			     GFS2_DIF_SYNC|			\
 197			     GFS2_DIF_SYSTEM|			\
 198			     GFS2_DIF_INHERIT_JDATA)
 199
 200/**
 201 * gfs2_set_flags - set flags on an inode
 202 * @inode: The inode
 203 * @flags: The flags to set
 204 * @mask: Indicates which flags are valid
 205 *
 206 */
 207static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
 208{
 209	struct inode *inode = filp->f_path.dentry->d_inode;
 210	struct gfs2_inode *ip = GFS2_I(inode);
 211	struct gfs2_sbd *sdp = GFS2_SB(inode);
 212	struct buffer_head *bh;
 213	struct gfs2_holder gh;
 214	int error;
 215	u32 new_flags, flags;
 216
 217	error = mnt_want_write(filp->f_path.mnt);
 218	if (error)
 219		return error;
 220
 221	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 222	if (error)
 223		goto out_drop_write;
 224
 225	error = -EACCES;
 226	if (!inode_owner_or_capable(inode))
 227		goto out;
 228
 229	error = 0;
 230	flags = ip->i_diskflags;
 231	new_flags = (flags & ~mask) | (reqflags & mask);
 232	if ((new_flags ^ flags) == 0)
 233		goto out;
 234
 235	error = -EINVAL;
 236	if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
 237		goto out;
 238
 239	error = -EPERM;
 240	if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
 241		goto out;
 242	if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
 243		goto out;
 244	if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
 245	    !capable(CAP_LINUX_IMMUTABLE))
 246		goto out;
 247	if (!IS_IMMUTABLE(inode)) {
 248		error = gfs2_permission(inode, MAY_WRITE);
 249		if (error)
 250			goto out;
 251	}
 252	if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
 253		if (flags & GFS2_DIF_JDATA)
 254			gfs2_log_flush(sdp, ip->i_gl);
 
 
 255		error = filemap_fdatawrite(inode->i_mapping);
 256		if (error)
 257			goto out;
 258		error = filemap_fdatawait(inode->i_mapping);
 259		if (error)
 260			goto out;
 
 
 261	}
 262	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
 263	if (error)
 264		goto out;
 265	error = gfs2_meta_inode_buffer(ip, &bh);
 266	if (error)
 267		goto out_trans_end;
 268	gfs2_trans_add_bh(ip->i_gl, bh, 1);
 
 269	ip->i_diskflags = new_flags;
 270	gfs2_dinode_out(ip, bh->b_data);
 271	brelse(bh);
 272	gfs2_set_inode_flags(inode);
 273	gfs2_set_aops(inode);
 274out_trans_end:
 275	gfs2_trans_end(sdp);
 276out:
 277	gfs2_glock_dq_uninit(&gh);
 278out_drop_write:
 279	mnt_drop_write(filp->f_path.mnt);
 280	return error;
 281}
 282
 283static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
 
 284{
 285	struct inode *inode = filp->f_path.dentry->d_inode;
 286	u32 fsflags, gfsflags;
 
 
 287
 288	if (get_user(fsflags, ptr))
 289		return -EFAULT;
 
 
 
 
 
 
 
 
 
 
 
 
 290
 291	gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
 292	if (!S_ISDIR(inode->i_mode)) {
 293		if (gfsflags & GFS2_DIF_INHERIT_JDATA)
 294			gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA);
 295		return do_gfs2_set_flags(filp, gfsflags, ~0);
 
 
 
 296	}
 297	return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
 
 
 
 
 
 
 
 
 
 
 
 
 298}
 299
 300static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 301{
 302	switch(cmd) {
 303	case FS_IOC_GETFLAGS:
 304		return gfs2_get_flags(filp, (u32 __user *)arg);
 305	case FS_IOC_SETFLAGS:
 306		return gfs2_set_flags(filp, (u32 __user *)arg);
 307	}
 
 308	return -ENOTTY;
 309}
 310
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 311/**
 312 * gfs2_allocate_page_backing - Use bmap to allocate blocks
 313 * @page: The (locked) page to allocate backing for
 
 314 *
 315 * We try to allocate all the blocks required for the page in
 316 * one go. This might fail for various reasons, so we keep
 317 * trying until all the blocks to back this page are allocated.
 318 * If some of the blocks are already allocated, thats ok too.
 319 */
 320
 321static int gfs2_allocate_page_backing(struct page *page)
 322{
 323	struct inode *inode = page->mapping->host;
 324	struct buffer_head bh;
 325	unsigned long size = PAGE_CACHE_SIZE;
 326	u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
 327
 328	do {
 329		bh.b_state = 0;
 330		bh.b_size = size;
 331		gfs2_block_map(inode, lblock, &bh, 1);
 332		if (!buffer_mapped(&bh))
 333			return -EIO;
 334		size -= bh.b_size;
 335		lblock += (bh.b_size >> inode->i_blkbits);
 336	} while(size > 0);
 
 
 
 
 337	return 0;
 338}
 339
 340/**
 341 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
 342 * @vma: The virtual memory area
 343 * @page: The page which is about to become writable
 344 *
 345 * When the page becomes writable, we need to ensure that we have
 346 * blocks allocated on disk to back that page.
 347 */
 348
 349static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 350{
 351	struct page *page = vmf->page;
 352	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
 353	struct gfs2_inode *ip = GFS2_I(inode);
 354	struct gfs2_sbd *sdp = GFS2_SB(inode);
 355	unsigned long last_index;
 356	u64 pos = page->index << PAGE_CACHE_SHIFT;
 357	unsigned int data_blocks, ind_blocks, rblocks;
 
 358	struct gfs2_holder gh;
 359	struct gfs2_alloc *al;
 360	int ret;
 
 
 
 361
 362	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 363	ret = gfs2_glock_nq(&gh);
 364	if (ret)
 365		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 366
 367	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
 368	set_bit(GIF_SW_PAGED, &ip->i_flags);
 369
 370	if (!gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE))
 
 
 
 
 
 
 
 
 
 
 
 371		goto out_unlock;
 372	ret = -ENOMEM;
 373	al = gfs2_alloc_get(ip);
 374	if (al == NULL)
 
 
 375		goto out_unlock;
 
 376
 377	ret = gfs2_quota_lock_check(ip);
 378	if (ret)
 379		goto out_alloc_put;
 380	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
 381	al->al_requested = data_blocks + ind_blocks;
 382	ret = gfs2_inplace_reserve(ip);
 383	if (ret)
 
 
 
 384		goto out_quota_unlock;
 
 385
 386	rblocks = RES_DINODE + ind_blocks;
 387	if (gfs2_is_jdata(ip))
 388		rblocks += data_blocks ? data_blocks : 1;
 389	if (ind_blocks || data_blocks) {
 390		rblocks += RES_STATFS + RES_QUOTA;
 391		rblocks += gfs2_rg_blocks(al);
 392	}
 393	ret = gfs2_trans_begin(sdp, rblocks, 0);
 394	if (ret)
 
 395		goto out_trans_fail;
 
 396
 397	lock_page(page);
 398	ret = -EINVAL;
 399	last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT;
 400	if (page->index > last_index)
 401		goto out_unlock_page;
 402	ret = 0;
 403	if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping)
 404		goto out_unlock_page;
 405	if (gfs2_is_stuffed(ip)) {
 406		ret = gfs2_unstuff_dinode(ip, page);
 407		if (ret)
 408			goto out_unlock_page;
 
 
 409	}
 410	ret = gfs2_allocate_page_backing(page);
 411
 412out_unlock_page:
 413	unlock_page(page);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 414	gfs2_trans_end(sdp);
 415out_trans_fail:
 416	gfs2_inplace_release(ip);
 417out_quota_unlock:
 418	gfs2_quota_unlock(ip);
 419out_alloc_put:
 420	gfs2_alloc_put(ip);
 421out_unlock:
 422	gfs2_glock_dq(&gh);
 423out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 424	gfs2_holder_uninit(&gh);
 425	if (ret == -ENOMEM)
 426		ret = VM_FAULT_OOM;
 427	else if (ret)
 428		ret = VM_FAULT_SIGBUS;
 429	return ret;
 430}
 431
 432static const struct vm_operations_struct gfs2_vm_ops = {
 433	.fault = filemap_fault,
 
 434	.page_mkwrite = gfs2_page_mkwrite,
 435};
 436
 437/**
 438 * gfs2_mmap -
 439 * @file: The file to map
 440 * @vma: The VMA which described the mapping
 441 *
 442 * There is no need to get a lock here unless we should be updating
 443 * atime. We ignore any locking errors since the only consequence is
 444 * a missed atime update (which will just be deferred until later).
 445 *
 446 * Returns: 0
 447 */
 448
 449static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
 450{
 451	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 452
 453	if (!(file->f_flags & O_NOATIME) &&
 454	    !IS_NOATIME(&ip->i_inode)) {
 455		struct gfs2_holder i_gh;
 456		int error;
 457
 458		gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 459		error = gfs2_glock_nq(&i_gh);
 460		if (error == 0) {
 461			file_accessed(file);
 462			gfs2_glock_dq(&i_gh);
 463		}
 464		gfs2_holder_uninit(&i_gh);
 465		if (error)
 466			return error;
 
 
 
 467	}
 468	vma->vm_ops = &gfs2_vm_ops;
 469	vma->vm_flags |= VM_CAN_NONLINEAR;
 470
 471	return 0;
 472}
 473
 474/**
 475 * gfs2_open - open a file
 476 * @inode: the inode to open
 477 * @file: the struct file for this opening
 
 
 
 
 
 478 *
 479 * Returns: errno
 480 */
 481
 482static int gfs2_open(struct inode *inode, struct file *file)
 483{
 484	struct gfs2_inode *ip = GFS2_I(inode);
 485	struct gfs2_holder i_gh;
 486	struct gfs2_file *fp;
 487	int error;
 
 
 
 
 
 488
 489	fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
 
 
 
 
 490	if (!fp)
 491		return -ENOMEM;
 492
 493	mutex_init(&fp->f_fl_mutex);
 494
 495	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
 496	file->private_data = fp;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 497
 498	if (S_ISREG(ip->i_inode.i_mode)) {
 499		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 500					   &i_gh);
 501		if (error)
 502			goto fail;
 
 
 503
 504		if (!(file->f_flags & O_LARGEFILE) &&
 505		    i_size_read(inode) > MAX_NON_LFS) {
 506			error = -EOVERFLOW;
 507			goto fail_gunlock;
 508		}
 509
 
 510		gfs2_glock_dq_uninit(&i_gh);
 511	}
 512
 513	return 0;
 514
 515fail_gunlock:
 516	gfs2_glock_dq_uninit(&i_gh);
 517fail:
 518	file->private_data = NULL;
 519	kfree(fp);
 520	return error;
 521}
 522
 523/**
 524 * gfs2_close - called to close a struct file
 525 * @inode: the inode the struct file belongs to
 526 * @file: the struct file being closed
 527 *
 528 * Returns: errno
 529 */
 530
 531static int gfs2_close(struct inode *inode, struct file *file)
 532{
 533	struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
 534	struct gfs2_file *fp;
 535
 536	fp = file->private_data;
 537	file->private_data = NULL;
 538
 539	if (gfs2_assert_warn(sdp, fp))
 540		return -EIO;
 541
 542	kfree(fp);
 543
 544	return 0;
 545}
 546
 547/**
 548 * gfs2_fsync - sync the dirty data for a file (across the cluster)
 549 * @file: the file that points to the dentry
 550 * @start: the start position in the file to sync
 551 * @end: the end position in the file to sync
 552 * @datasync: set if we can ignore timestamp changes
 553 *
 554 * The VFS will flush data for us. We only need to worry
 555 * about metadata here.
 
 
 
 
 
 
 
 
 556 *
 557 * Returns: errno
 558 */
 559
 560static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 561		      int datasync)
 562{
 563	struct inode *inode = file->f_mapping->host;
 564	int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC);
 
 565	struct gfs2_inode *ip = GFS2_I(inode);
 566	int ret;
 567
 568	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
 569	if (ret)
 570		return ret;
 571	mutex_lock(&inode->i_mutex);
 
 572
 
 
 573	if (datasync)
 574		sync_state &= ~I_DIRTY_SYNC;
 575
 576	if (sync_state) {
 577		ret = sync_inode_metadata(inode, 1);
 578		if (ret) {
 579			mutex_unlock(&inode->i_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 580			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 581		}
 582		gfs2_ail_flush(ip->i_gl);
 583	}
 
 
 
 584
 585	mutex_unlock(&inode->i_mutex);
 586	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 587}
 588
 589/**
 590 * gfs2_file_aio_write - Perform a write to a file
 591 * @iocb: The io context
 592 * @iov: The data to write
 593 * @nr_segs: Number of @iov segments
 594 * @pos: The file position
 595 *
 596 * We have to do a lock/unlock here to refresh the inode size for
 597 * O_APPEND writes, otherwise we can land up writing at the wrong
 598 * offset. There is still a race, but provided the app is using its
 599 * own file locking, this will make O_APPEND work as expected.
 600 *
 601 */
 602
 603static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 604				   unsigned long nr_segs, loff_t pos)
 605{
 606	struct file *file = iocb->ki_filp;
 
 
 
 
 607
 608	if (file->f_flags & O_APPEND) {
 609		struct dentry *dentry = file->f_dentry;
 610		struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 611		struct gfs2_holder gh;
 612		int ret;
 613
 
 614		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 615		if (ret)
 616			return ret;
 617		gfs2_glock_dq_uninit(&gh);
 618	}
 619
 620	return generic_file_aio_write(iocb, iov, nr_segs, pos);
 621}
 622
 623static int empty_write_end(struct page *page, unsigned from,
 624			   unsigned to, int mode)
 625{
 626	struct inode *inode = page->mapping->host;
 627	struct gfs2_inode *ip = GFS2_I(inode);
 628	struct buffer_head *bh;
 629	unsigned offset, blksize = 1 << inode->i_blkbits;
 630	pgoff_t end_index = i_size_read(inode) >> PAGE_CACHE_SHIFT;
 631
 632	zero_user(page, from, to-from);
 633	mark_page_accessed(page);
 634
 635	if (page->index < end_index || !(mode & FALLOC_FL_KEEP_SIZE)) {
 636		if (!gfs2_is_writeback(ip))
 637			gfs2_page_add_databufs(ip, page, from, to);
 638
 639		block_commit_write(page, from, to);
 640		return 0;
 641	}
 
 
 
 
 
 
 642
 643	offset = 0;
 644	bh = page_buffers(page);
 645	while (offset < to) {
 646		if (offset >= from) {
 647			set_buffer_uptodate(bh);
 648			mark_buffer_dirty(bh);
 649			clear_buffer_new(bh);
 650			write_dirty_buffer(bh, WRITE);
 651		}
 652		offset += blksize;
 653		bh = bh->b_this_page;
 654	}
 655
 656	offset = 0;
 657	bh = page_buffers(page);
 658	while (offset < to) {
 659		if (offset >= from) {
 660			wait_on_buffer(bh);
 661			if (!buffer_uptodate(bh))
 662				return -EIO;
 663		}
 664		offset += blksize;
 665		bh = bh->b_this_page;
 666	}
 667	return 0;
 668}
 669
 670static int needs_empty_write(sector_t block, struct inode *inode)
 671{
 672	int error;
 673	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 674
 675	bh_map.b_size = 1 << inode->i_blkbits;
 676	error = gfs2_block_map(inode, block, &bh_map, 0);
 677	if (unlikely(error))
 678		return error;
 679	return !buffer_mapped(&bh_map);
 680}
 681
 682static int write_empty_blocks(struct page *page, unsigned from, unsigned to,
 683			      int mode)
 684{
 685	struct inode *inode = page->mapping->host;
 686	unsigned start, end, next, blksize;
 687	sector_t block = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
 688	int ret;
 
 
 
 689
 690	blksize = 1 << inode->i_blkbits;
 691	next = end = 0;
 692	while (next < from) {
 693		next += blksize;
 694		block++;
 695	}
 696	start = next;
 697	do {
 698		next += blksize;
 699		ret = needs_empty_write(block, inode);
 700		if (unlikely(ret < 0))
 701			return ret;
 702		if (ret == 0) {
 703			if (end) {
 704				ret = __block_write_begin(page, start, end - start,
 705							  gfs2_block_map);
 706				if (unlikely(ret))
 707					return ret;
 708				ret = empty_write_end(page, start, end, mode);
 709				if (unlikely(ret))
 710					return ret;
 711				end = 0;
 712			}
 713			start = next;
 714		}
 715		else
 716			end = next;
 717		block++;
 718	} while (next < to);
 719
 720	if (end) {
 721		ret = __block_write_begin(page, start, end - start, gfs2_block_map);
 722		if (unlikely(ret))
 723			return ret;
 724		ret = empty_write_end(page, start, end, mode);
 725		if (unlikely(ret))
 726			return ret;
 727	}
 728
 729	return 0;
 
 
 730}
 731
 732static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
 733			   int mode)
 734{
 
 735	struct gfs2_inode *ip = GFS2_I(inode);
 
 736	struct buffer_head *dibh;
 737	int error;
 738	u64 start = offset >> PAGE_CACHE_SHIFT;
 739	unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
 740	u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
 741	pgoff_t curr;
 742	struct page *page;
 743	unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
 744	unsigned int from, to;
 745
 746	if (!end_offset)
 747		end_offset = PAGE_CACHE_SIZE;
 748
 749	error = gfs2_meta_inode_buffer(ip, &dibh);
 750	if (unlikely(error))
 751		goto out;
 752
 753	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 754
 755	if (gfs2_is_stuffed(ip)) {
 756		error = gfs2_unstuff_dinode(ip, NULL);
 757		if (unlikely(error))
 758			goto out;
 759	}
 760
 761	curr = start;
 762	offset = start << PAGE_CACHE_SHIFT;
 763	from = start_offset;
 764	to = PAGE_CACHE_SIZE;
 765	while (curr <= end) {
 766		page = grab_cache_page_write_begin(inode->i_mapping, curr,
 767						   AOP_FLAG_NOFS);
 768		if (unlikely(!page)) {
 769			error = -ENOMEM;
 770			goto out;
 771		}
 772
 773		if (curr == end)
 774			to = end_offset;
 775		error = write_empty_blocks(page, from, to, mode);
 776		if (!error && offset + to > inode->i_size &&
 777		    !(mode & FALLOC_FL_KEEP_SIZE)) {
 778			i_size_write(inode, offset + to);
 779		}
 780		unlock_page(page);
 781		page_cache_release(page);
 782		if (error)
 783			goto out;
 784		curr++;
 785		offset += PAGE_CACHE_SIZE;
 786		from = 0;
 
 
 
 
 
 
 
 787	}
 788
 789	gfs2_dinode_out(ip, dibh->b_data);
 790	mark_inode_dirty(inode);
 791
 792	brelse(dibh);
 793
 794out:
 
 795	return error;
 796}
 797
 798static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
 799			    unsigned int *data_blocks, unsigned int *ind_blocks)
 
 
 
 
 
 
 
 
 
 
 
 
 800{
 
 801	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 802	unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
 803	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
 804
 805	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
 806		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
 807		max_data -= tmp;
 808	}
 809	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
 810	   so it might end up with fewer data blocks */
 811	if (max_data <= *data_blocks)
 812		return;
 813	*data_blocks = max_data;
 814	*ind_blocks = max_blocks - max_data;
 815	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
 816	if (*len > max) {
 817		*len = max;
 818		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
 819	}
 820}
 821
 822static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
 823			   loff_t len)
 824{
 825	struct inode *inode = file->f_path.dentry->d_inode;
 826	struct gfs2_sbd *sdp = GFS2_SB(inode);
 827	struct gfs2_inode *ip = GFS2_I(inode);
 
 828	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
 829	loff_t bytes, max_bytes;
 830	struct gfs2_alloc *al;
 831	int error;
 
 
 832	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
 833	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
 834	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
 835
 836	/* We only support the FALLOC_FL_KEEP_SIZE mode */
 837	if (mode & ~FALLOC_FL_KEEP_SIZE)
 838		return -EOPNOTSUPP;
 839
 840	offset &= bsize_mask;
 841
 842	len = next - offset;
 843	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
 844	if (!bytes)
 845		bytes = UINT_MAX;
 846	bytes &= bsize_mask;
 847	if (bytes == 0)
 848		bytes = sdp->sd_sb.sb_bsize;
 849
 850	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
 851	error = gfs2_glock_nq(&ip->i_gh);
 852	if (unlikely(error))
 853		goto out_uninit;
 854
 855	if (!gfs2_write_alloc_required(ip, offset, len))
 856		goto out_unlock;
 857
 858	while (len > 0) {
 859		if (len < bytes)
 860			bytes = len;
 861		al = gfs2_alloc_get(ip);
 862		if (!al) {
 863			error = -ENOMEM;
 864			goto out_unlock;
 865		}
 866
 867		error = gfs2_quota_lock_check(ip);
 868		if (error)
 869			goto out_alloc_put;
 870
 871retry:
 
 
 
 
 
 872		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
 
 873
 874		al->al_requested = data_blocks + ind_blocks;
 875		error = gfs2_inplace_reserve(ip);
 876		if (error) {
 877			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
 878				bytes >>= 1;
 879				bytes &= bsize_mask;
 880				if (bytes == 0)
 881					bytes = sdp->sd_sb.sb_bsize;
 882				goto retry;
 883			}
 
 884			goto out_qunlock;
 885		}
 886		max_bytes = bytes;
 887		calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
 888		al->al_requested = data_blocks + ind_blocks;
 
 
 
 
 
 
 889
 890		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
 891			  RES_RG_HDR + gfs2_rg_blocks(al);
 892		if (gfs2_is_jdata(ip))
 893			rblocks += data_blocks ? data_blocks : 1;
 894
 895		error = gfs2_trans_begin(sdp, rblocks,
 896					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
 897		if (error)
 898			goto out_trans_fail;
 899
 900		error = fallocate_chunk(inode, offset, max_bytes, mode);
 901		gfs2_trans_end(sdp);
 902
 903		if (error)
 904			goto out_trans_fail;
 905
 906		len -= max_bytes;
 907		offset += max_bytes;
 908		gfs2_inplace_release(ip);
 909		gfs2_quota_unlock(ip);
 910		gfs2_alloc_put(ip);
 911	}
 912	goto out_unlock;
 
 
 
 
 
 
 
 
 
 913
 914out_trans_fail:
 915	gfs2_inplace_release(ip);
 916out_qunlock:
 917	gfs2_quota_unlock(ip);
 918out_alloc_put:
 919	gfs2_alloc_put(ip);
 920out_unlock:
 921	gfs2_glock_dq(&ip->i_gh);
 922out_uninit:
 923	gfs2_holder_uninit(&ip->i_gh);
 924	return error;
 925}
 926
 927#ifdef CONFIG_GFS2_FS_LOCKING_DLM
 
 
 
 
 
 
 928
 929/**
 930 * gfs2_setlease - acquire/release a file lease
 931 * @file: the file pointer
 932 * @arg: lease type
 933 * @fl: file lock
 934 *
 935 * We don't currently have a way to enforce a lease across the whole
 936 * cluster; until we do, disable leases (by just returning -EINVAL),
 937 * unless the administrator has requested purely local locking.
 938 *
 939 * Locking: called under lock_flocks
 940 *
 941 * Returns: errno
 942 */
 943
 944static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 945{
 946	return -EINVAL;
 
 
 
 
 
 947}
 948
 
 
 949/**
 950 * gfs2_lock - acquire/release a posix lock on a file
 951 * @file: the file pointer
 952 * @cmd: either modify or retrieve lock state, possibly wait
 953 * @fl: type and range of lock
 954 *
 955 * Returns: errno
 956 */
 957
 958static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
 959{
 960	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 961	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
 962	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 963
 964	if (!(fl->fl_flags & FL_POSIX))
 965		return -ENOLCK;
 966	if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
 967		return -ENOLCK;
 968
 969	if (cmd == F_CANCELLK) {
 970		/* Hack: */
 971		cmd = F_SETLK;
 972		fl->fl_type = F_UNLCK;
 973	}
 974	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 975		return -EIO;
 976	if (IS_GETLK(cmd))
 
 
 
 977		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
 978	else if (fl->fl_type == F_UNLCK)
 979		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
 980	else
 981		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
 982}
 983
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 984static int do_flock(struct file *file, int cmd, struct file_lock *fl)
 985{
 986	struct gfs2_file *fp = file->private_data;
 987	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
 988	struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
 989	struct gfs2_glock *gl;
 990	unsigned int state;
 991	int flags;
 992	int error = 0;
 
 993
 994	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
 995	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
 
 
 996
 997	mutex_lock(&fp->f_fl_mutex);
 998
 999	gl = fl_gh->gh_gl;
1000	if (gl) {
1001		if (fl_gh->gh_state == state)
1002			goto out;
1003		flock_lock_file_wait(file,
1004				     &(struct file_lock){.fl_type = F_UNLCK});
1005		gfs2_glock_dq_wait(fl_gh);
 
 
1006		gfs2_holder_reinit(state, flags, fl_gh);
1007	} else {
1008		error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1009				       &gfs2_flock_glops, CREATE, &gl);
1010		if (error)
1011			goto out;
 
1012		gfs2_holder_init(gl, state, flags, fl_gh);
 
1013		gfs2_glock_put(gl);
1014	}
1015	error = gfs2_glock_nq(fl_gh);
 
 
 
 
 
 
 
1016	if (error) {
1017		gfs2_holder_uninit(fl_gh);
1018		if (error == GLR_TRYFAILED)
1019			error = -EAGAIN;
1020	} else {
1021		error = flock_lock_file_wait(file, fl);
1022		gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1023	}
1024
1025out:
1026	mutex_unlock(&fp->f_fl_mutex);
1027	return error;
1028}
1029
1030static void do_unflock(struct file *file, struct file_lock *fl)
1031{
1032	struct gfs2_file *fp = file->private_data;
1033	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1034
1035	mutex_lock(&fp->f_fl_mutex);
1036	flock_lock_file_wait(file, fl);
1037	if (fl_gh->gh_gl) {
1038		gfs2_glock_dq_wait(fl_gh);
1039		gfs2_holder_uninit(fl_gh);
1040	}
1041	mutex_unlock(&fp->f_fl_mutex);
1042}
1043
1044/**
1045 * gfs2_flock - acquire/release a flock lock on a file
1046 * @file: the file pointer
1047 * @cmd: either modify or retrieve lock state, possibly wait
1048 * @fl: type and range of lock
1049 *
1050 * Returns: errno
1051 */
1052
1053static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1054{
1055	if (!(fl->fl_flags & FL_FLOCK))
1056		return -ENOLCK;
1057	if (fl->fl_type & LOCK_MAND)
1058		return -EOPNOTSUPP;
1059
1060	if (fl->fl_type == F_UNLCK) {
1061		do_unflock(file, fl);
1062		return 0;
1063	} else {
1064		return do_flock(file, cmd, fl);
1065	}
1066}
1067
1068const struct file_operations gfs2_file_fops = {
1069	.llseek		= gfs2_llseek,
1070	.read		= do_sync_read,
1071	.aio_read	= generic_file_aio_read,
1072	.write		= do_sync_write,
1073	.aio_write	= gfs2_file_aio_write,
1074	.unlocked_ioctl	= gfs2_ioctl,
 
1075	.mmap		= gfs2_mmap,
1076	.open		= gfs2_open,
1077	.release	= gfs2_close,
1078	.fsync		= gfs2_fsync,
1079	.lock		= gfs2_lock,
1080	.flock		= gfs2_flock,
1081	.splice_read	= generic_file_splice_read,
1082	.splice_write	= generic_file_splice_write,
1083	.setlease	= gfs2_setlease,
1084	.fallocate	= gfs2_fallocate,
1085};
1086
1087const struct file_operations gfs2_dir_fops = {
1088	.readdir	= gfs2_readdir,
1089	.unlocked_ioctl	= gfs2_ioctl,
 
1090	.open		= gfs2_open,
1091	.release	= gfs2_close,
1092	.fsync		= gfs2_fsync,
1093	.lock		= gfs2_lock,
1094	.flock		= gfs2_flock,
1095	.llseek		= default_llseek,
1096};
1097
1098#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1099
1100const struct file_operations gfs2_file_fops_nolock = {
1101	.llseek		= gfs2_llseek,
1102	.read		= do_sync_read,
1103	.aio_read	= generic_file_aio_read,
1104	.write		= do_sync_write,
1105	.aio_write	= gfs2_file_aio_write,
1106	.unlocked_ioctl	= gfs2_ioctl,
 
1107	.mmap		= gfs2_mmap,
1108	.open		= gfs2_open,
1109	.release	= gfs2_close,
1110	.fsync		= gfs2_fsync,
1111	.splice_read	= generic_file_splice_read,
1112	.splice_write	= generic_file_splice_write,
1113	.setlease	= generic_setlease,
1114	.fallocate	= gfs2_fallocate,
1115};
1116
1117const struct file_operations gfs2_dir_fops_nolock = {
1118	.readdir	= gfs2_readdir,
1119	.unlocked_ioctl	= gfs2_ioctl,
 
1120	.open		= gfs2_open,
1121	.release	= gfs2_close,
1122	.fsync		= gfs2_fsync,
1123	.llseek		= default_llseek,
1124};
1125
v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
 
 
 
 
   5 */
   6
   7#include <linux/slab.h>
   8#include <linux/spinlock.h>
   9#include <linux/compat.h>
  10#include <linux/completion.h>
  11#include <linux/buffer_head.h>
  12#include <linux/pagemap.h>
  13#include <linux/uio.h>
  14#include <linux/blkdev.h>
  15#include <linux/mm.h>
  16#include <linux/mount.h>
  17#include <linux/fs.h>
  18#include <linux/filelock.h>
  19#include <linux/gfs2_ondisk.h>
 
  20#include <linux/falloc.h>
  21#include <linux/swap.h>
  22#include <linux/crc32.h>
  23#include <linux/writeback.h>
  24#include <linux/uaccess.h>
  25#include <linux/dlm.h>
  26#include <linux/dlm_plock.h>
  27#include <linux/delay.h>
  28#include <linux/backing-dev.h>
  29#include <linux/fileattr.h>
  30
  31#include "gfs2.h"
  32#include "incore.h"
  33#include "bmap.h"
  34#include "aops.h"
  35#include "dir.h"
  36#include "glock.h"
  37#include "glops.h"
  38#include "inode.h"
  39#include "log.h"
  40#include "meta_io.h"
  41#include "quota.h"
  42#include "rgrp.h"
  43#include "trans.h"
  44#include "util.h"
  45
  46/**
  47 * gfs2_llseek - seek to a location in a file
  48 * @file: the file
  49 * @offset: the offset
  50 * @whence: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
  51 *
  52 * SEEK_END requires the glock for the file because it references the
  53 * file's size.
  54 *
  55 * Returns: The new offset, or errno
  56 */
  57
  58static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence)
  59{
  60	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
  61	struct gfs2_holder i_gh;
  62	loff_t error;
  63
  64	switch (whence) {
  65	case SEEK_END:
  66		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
  67					   &i_gh);
  68		if (!error) {
  69			error = generic_file_llseek(file, offset, whence);
  70			gfs2_glock_dq_uninit(&i_gh);
  71		}
  72		break;
  73
  74	case SEEK_DATA:
  75		error = gfs2_seek_data(file, offset);
  76		break;
  77
  78	case SEEK_HOLE:
  79		error = gfs2_seek_hole(file, offset);
  80		break;
  81
  82	case SEEK_CUR:
  83	case SEEK_SET:
  84		/*
  85		 * These don't reference inode->i_size and don't depend on the
  86		 * block mapping, so we don't need the glock.
  87		 */
  88		error = generic_file_llseek(file, offset, whence);
  89		break;
  90	default:
  91		error = -EINVAL;
  92	}
  93
  94	return error;
  95}
  96
  97/**
  98 * gfs2_readdir - Iterator for a directory
  99 * @file: The directory to read from
 100 * @ctx: What to feed directory entries to
 
 101 *
 102 * Returns: errno
 103 */
 104
 105static int gfs2_readdir(struct file *file, struct dir_context *ctx)
 106{
 107	struct inode *dir = file->f_mapping->host;
 108	struct gfs2_inode *dip = GFS2_I(dir);
 109	struct gfs2_holder d_gh;
 
 110	int error;
 111
 112	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
 113	if (error)
 
 
 114		return error;
 
 115
 116	error = gfs2_dir_read(dir, ctx, &file->f_ra);
 117
 118	gfs2_glock_dq_uninit(&d_gh);
 119
 
 
 120	return error;
 121}
 122
 123/*
 124 * struct fsflag_gfs2flag
 
 
 
 
 
 125 *
 126 * The FS_JOURNAL_DATA_FL flag maps to GFS2_DIF_INHERIT_JDATA for directories,
 127 * and to GFS2_DIF_JDATA for non-directories.
 128 */
 129static struct {
 130	u32 fsflag;
 131	u32 gfsflag;
 132} fsflag_gfs2flag[] = {
 133	{FS_SYNC_FL, GFS2_DIF_SYNC},
 134	{FS_IMMUTABLE_FL, GFS2_DIF_IMMUTABLE},
 135	{FS_APPEND_FL, GFS2_DIF_APPENDONLY},
 136	{FS_NOATIME_FL, GFS2_DIF_NOATIME},
 137	{FS_INDEX_FL, GFS2_DIF_EXHASH},
 138	{FS_TOPDIR_FL, GFS2_DIF_TOPDIR},
 139	{FS_JOURNAL_DATA_FL, GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA},
 
 
 
 
 
 
 
 
 140};
 141
 142static inline u32 gfs2_gfsflags_to_fsflags(struct inode *inode, u32 gfsflags)
 143{
 144	int i;
 145	u32 fsflags = 0;
 
 
 
 
 146
 147	if (S_ISDIR(inode->i_mode))
 148		gfsflags &= ~GFS2_DIF_JDATA;
 149	else
 150		gfsflags &= ~GFS2_DIF_INHERIT_JDATA;
 151
 152	for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++)
 153		if (gfsflags & fsflag_gfs2flag[i].gfsflag)
 154			fsflags |= fsflag_gfs2flag[i].fsflag;
 155	return fsflags;
 156}
 157
 158int gfs2_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 159{
 160	struct inode *inode = d_inode(dentry);
 161	struct gfs2_inode *ip = GFS2_I(inode);
 162	struct gfs2_holder gh;
 163	int error;
 164	u32 fsflags;
 165
 166	if (d_is_special(dentry))
 167		return -ENOTTY;
 168
 169	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 170	error = gfs2_glock_nq(&gh);
 171	if (error)
 172		goto out_uninit;
 173
 174	fsflags = gfs2_gfsflags_to_fsflags(inode, ip->i_diskflags);
 175
 176	fileattr_fill_flags(fa, fsflags);
 
 
 177
 178	gfs2_glock_dq(&gh);
 179out_uninit:
 180	gfs2_holder_uninit(&gh);
 181	return error;
 182}
 183
 184void gfs2_set_inode_flags(struct inode *inode)
 185{
 186	struct gfs2_inode *ip = GFS2_I(inode);
 187	unsigned int flags = inode->i_flags;
 188
 189	flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_NOSEC);
 190	if ((ip->i_eattr == 0) && !is_sxid(inode->i_mode))
 191		flags |= S_NOSEC;
 192	if (ip->i_diskflags & GFS2_DIF_IMMUTABLE)
 193		flags |= S_IMMUTABLE;
 194	if (ip->i_diskflags & GFS2_DIF_APPENDONLY)
 195		flags |= S_APPEND;
 196	if (ip->i_diskflags & GFS2_DIF_NOATIME)
 197		flags |= S_NOATIME;
 198	if (ip->i_diskflags & GFS2_DIF_SYNC)
 199		flags |= S_SYNC;
 200	inode->i_flags = flags;
 201}
 202
 203/* Flags that can be set by user space */
 204#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA|			\
 205			     GFS2_DIF_IMMUTABLE|		\
 206			     GFS2_DIF_APPENDONLY|		\
 207			     GFS2_DIF_NOATIME|			\
 208			     GFS2_DIF_SYNC|			\
 209			     GFS2_DIF_TOPDIR|			\
 210			     GFS2_DIF_INHERIT_JDATA)
 211
 212/**
 213 * do_gfs2_set_flags - set flags on an inode
 214 * @inode: The inode
 215 * @reqflags: The flags to set
 216 * @mask: Indicates which flags are valid
 217 *
 218 */
 219static int do_gfs2_set_flags(struct inode *inode, u32 reqflags, u32 mask)
 220{
 
 221	struct gfs2_inode *ip = GFS2_I(inode);
 222	struct gfs2_sbd *sdp = GFS2_SB(inode);
 223	struct buffer_head *bh;
 224	struct gfs2_holder gh;
 225	int error;
 226	u32 new_flags, flags;
 227
 
 
 
 
 228	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 229	if (error)
 230		return error;
 
 
 
 
 231
 232	error = 0;
 233	flags = ip->i_diskflags;
 234	new_flags = (flags & ~mask) | (reqflags & mask);
 235	if ((new_flags ^ flags) == 0)
 236		goto out;
 237
 
 
 
 
 
 
 
 
 
 
 
 
 238	if (!IS_IMMUTABLE(inode)) {
 239		error = gfs2_permission(&nop_mnt_idmap, inode, MAY_WRITE);
 240		if (error)
 241			goto out;
 242	}
 243	if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
 244		if (new_flags & GFS2_DIF_JDATA)
 245			gfs2_log_flush(sdp, ip->i_gl,
 246				       GFS2_LOG_HEAD_FLUSH_NORMAL |
 247				       GFS2_LFC_SET_FLAGS);
 248		error = filemap_fdatawrite(inode->i_mapping);
 249		if (error)
 250			goto out;
 251		error = filemap_fdatawait(inode->i_mapping);
 252		if (error)
 253			goto out;
 254		if (new_flags & GFS2_DIF_JDATA)
 255			gfs2_ordered_del_inode(ip);
 256	}
 257	error = gfs2_trans_begin(sdp, RES_DINODE, 0);
 258	if (error)
 259		goto out;
 260	error = gfs2_meta_inode_buffer(ip, &bh);
 261	if (error)
 262		goto out_trans_end;
 263	inode_set_ctime_current(inode);
 264	gfs2_trans_add_meta(ip->i_gl, bh);
 265	ip->i_diskflags = new_flags;
 266	gfs2_dinode_out(ip, bh->b_data);
 267	brelse(bh);
 268	gfs2_set_inode_flags(inode);
 269	gfs2_set_aops(inode);
 270out_trans_end:
 271	gfs2_trans_end(sdp);
 272out:
 273	gfs2_glock_dq_uninit(&gh);
 
 
 274	return error;
 275}
 276
 277int gfs2_fileattr_set(struct mnt_idmap *idmap,
 278		      struct dentry *dentry, struct fileattr *fa)
 279{
 280	struct inode *inode = d_inode(dentry);
 281	u32 fsflags = fa->flags, gfsflags = 0;
 282	u32 mask;
 283	int i;
 284
 285	if (d_is_special(dentry))
 286		return -ENOTTY;
 287
 288	if (fileattr_has_fsx(fa))
 289		return -EOPNOTSUPP;
 290
 291	for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) {
 292		if (fsflags & fsflag_gfs2flag[i].fsflag) {
 293			fsflags &= ~fsflag_gfs2flag[i].fsflag;
 294			gfsflags |= fsflag_gfs2flag[i].gfsflag;
 295		}
 296	}
 297	if (fsflags || gfsflags & ~GFS2_FLAGS_USER_SET)
 298		return -EINVAL;
 299
 300	mask = GFS2_FLAGS_USER_SET;
 301	if (S_ISDIR(inode->i_mode)) {
 302		mask &= ~GFS2_DIF_JDATA;
 303	} else {
 304		/* The GFS2_DIF_TOPDIR flag is only valid for directories. */
 305		if (gfsflags & GFS2_DIF_TOPDIR)
 306			return -EINVAL;
 307		mask &= ~(GFS2_DIF_TOPDIR | GFS2_DIF_INHERIT_JDATA);
 308	}
 309
 310	return do_gfs2_set_flags(inode, gfsflags, mask);
 311}
 312
 313static int gfs2_getlabel(struct file *filp, char __user *label)
 314{
 315	struct inode *inode = file_inode(filp);
 316	struct gfs2_sbd *sdp = GFS2_SB(inode);
 317
 318	if (copy_to_user(label, sdp->sd_sb.sb_locktable, GFS2_LOCKNAME_LEN))
 319		return -EFAULT;
 320
 321	return 0;
 322}
 323
 324static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 325{
 326	switch(cmd) {
 327	case FITRIM:
 328		return gfs2_fitrim(filp, (void __user *)arg);
 329	case FS_IOC_GETFSLABEL:
 330		return gfs2_getlabel(filp, (char __user *)arg);
 331	}
 332
 333	return -ENOTTY;
 334}
 335
 336#ifdef CONFIG_COMPAT
 337static long gfs2_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 338{
 339	switch(cmd) {
 340	/* Keep this list in sync with gfs2_ioctl */
 341	case FITRIM:
 342	case FS_IOC_GETFSLABEL:
 343		break;
 344	default:
 345		return -ENOIOCTLCMD;
 346	}
 347
 348	return gfs2_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
 349}
 350#else
 351#define gfs2_compat_ioctl NULL
 352#endif
 353
 354/**
 355 * gfs2_size_hint - Give a hint to the size of a write request
 356 * @filep: The struct file
 357 * @offset: The file offset of the write
 358 * @size: The length of the write
 359 *
 360 * When we are about to do a write, this function records the total
 361 * write size in order to provide a suitable hint to the lower layers
 362 * about how many blocks will be required.
 363 *
 364 */
 365
 366static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size)
 367{
 368	struct inode *inode = file_inode(filep);
 369	struct gfs2_sbd *sdp = GFS2_SB(inode);
 370	struct gfs2_inode *ip = GFS2_I(inode);
 371	size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift;
 372	int hint = min_t(size_t, INT_MAX, blks);
 373
 374	if (hint > atomic_read(&ip->i_sizehint))
 375		atomic_set(&ip->i_sizehint, hint);
 376}
 377
 378/**
 379 * gfs2_allocate_page_backing - Allocate blocks for a write fault
 380 * @page: The (locked) page to allocate backing for
 381 * @length: Size of the allocation
 382 *
 383 * We try to allocate all the blocks required for the page in one go.  This
 384 * might fail for various reasons, so we keep trying until all the blocks to
 385 * back this page are allocated.  If some of the blocks are already allocated,
 386 * that is ok too.
 387 */
 388static int gfs2_allocate_page_backing(struct page *page, unsigned int length)
 
 389{
 390	u64 pos = page_offset(page);
 
 
 
 391
 392	do {
 393		struct iomap iomap = { };
 394
 395		if (gfs2_iomap_alloc(page->mapping->host, pos, length, &iomap))
 
 396			return -EIO;
 397
 398		if (length < iomap.length)
 399			iomap.length = length;
 400		length -= iomap.length;
 401		pos += iomap.length;
 402	} while (length > 0);
 403
 404	return 0;
 405}
 406
 407/**
 408 * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable
 409 * @vmf: The virtual memory fault containing the page to become writable
 
 410 *
 411 * When the page becomes writable, we need to ensure that we have
 412 * blocks allocated on disk to back that page.
 413 */
 414
 415static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
 416{
 417	struct page *page = vmf->page;
 418	struct inode *inode = file_inode(vmf->vma->vm_file);
 419	struct gfs2_inode *ip = GFS2_I(inode);
 420	struct gfs2_sbd *sdp = GFS2_SB(inode);
 421	struct gfs2_alloc_parms ap = {};
 422	u64 offset = page_offset(page);
 423	unsigned int data_blocks, ind_blocks, rblocks;
 424	vm_fault_t ret = VM_FAULT_LOCKED;
 425	struct gfs2_holder gh;
 426	unsigned int length;
 427	loff_t size;
 428	int err;
 429
 430	sb_start_pagefault(inode->i_sb);
 431
 432	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 433	err = gfs2_glock_nq(&gh);
 434	if (err) {
 435		ret = vmf_fs_error(err);
 436		goto out_uninit;
 437	}
 438
 439	/* Check page index against inode size */
 440	size = i_size_read(inode);
 441	if (offset >= size) {
 442		ret = VM_FAULT_SIGBUS;
 443		goto out_unlock;
 444	}
 445
 446	/* Update file times before taking page lock */
 447	file_update_time(vmf->vma->vm_file);
 448
 449	/* page is wholly or partially inside EOF */
 450	if (size - offset < PAGE_SIZE)
 451		length = size - offset;
 452	else
 453		length = PAGE_SIZE;
 454
 455	gfs2_size_hint(vmf->vma->vm_file, offset, length);
 456
 457	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
 458	set_bit(GIF_SW_PAGED, &ip->i_flags);
 459
 460	/*
 461	 * iomap_writepage / iomap_writepages currently don't support inline
 462	 * files, so always unstuff here.
 463	 */
 464
 465	if (!gfs2_is_stuffed(ip) &&
 466	    !gfs2_write_alloc_required(ip, offset, length)) {
 467		lock_page(page);
 468		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
 469			ret = VM_FAULT_NOPAGE;
 470			unlock_page(page);
 471		}
 472		goto out_unlock;
 473	}
 474
 475	err = gfs2_rindex_update(sdp);
 476	if (err) {
 477		ret = vmf_fs_error(err);
 478		goto out_unlock;
 479	}
 480
 481	gfs2_write_calc_reserv(ip, length, &data_blocks, &ind_blocks);
 482	ap.target = data_blocks + ind_blocks;
 483	err = gfs2_quota_lock_check(ip, &ap);
 484	if (err) {
 485		ret = vmf_fs_error(err);
 486		goto out_unlock;
 487	}
 488	err = gfs2_inplace_reserve(ip, &ap);
 489	if (err) {
 490		ret = vmf_fs_error(err);
 491		goto out_quota_unlock;
 492	}
 493
 494	rblocks = RES_DINODE + ind_blocks;
 495	if (gfs2_is_jdata(ip))
 496		rblocks += data_blocks ? data_blocks : 1;
 497	if (ind_blocks || data_blocks) {
 498		rblocks += RES_STATFS + RES_QUOTA;
 499		rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
 500	}
 501	err = gfs2_trans_begin(sdp, rblocks, 0);
 502	if (err) {
 503		ret = vmf_fs_error(err);
 504		goto out_trans_fail;
 505	}
 506
 507	/* Unstuff, if required, and allocate backing blocks for page */
 
 
 
 
 
 
 
 508	if (gfs2_is_stuffed(ip)) {
 509		err = gfs2_unstuff_dinode(ip);
 510		if (err) {
 511			ret = vmf_fs_error(err);
 512			goto out_trans_end;
 513		}
 514	}
 
 515
 516	lock_page(page);
 517	/* If truncated, we must retry the operation, we may have raced
 518	 * with the glock demotion code.
 519	 */
 520	if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
 521		ret = VM_FAULT_NOPAGE;
 522		goto out_page_locked;
 523	}
 524
 525	err = gfs2_allocate_page_backing(page, length);
 526	if (err)
 527		ret = vmf_fs_error(err);
 528
 529out_page_locked:
 530	if (ret != VM_FAULT_LOCKED)
 531		unlock_page(page);
 532out_trans_end:
 533	gfs2_trans_end(sdp);
 534out_trans_fail:
 535	gfs2_inplace_release(ip);
 536out_quota_unlock:
 537	gfs2_quota_unlock(ip);
 
 
 538out_unlock:
 539	gfs2_glock_dq(&gh);
 540out_uninit:
 541	gfs2_holder_uninit(&gh);
 542	if (ret == VM_FAULT_LOCKED) {
 543		set_page_dirty(page);
 544		wait_for_stable_page(page);
 545	}
 546	sb_end_pagefault(inode->i_sb);
 547	return ret;
 548}
 549
 550static vm_fault_t gfs2_fault(struct vm_fault *vmf)
 551{
 552	struct inode *inode = file_inode(vmf->vma->vm_file);
 553	struct gfs2_inode *ip = GFS2_I(inode);
 554	struct gfs2_holder gh;
 555	vm_fault_t ret;
 556	int err;
 557
 558	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 559	err = gfs2_glock_nq(&gh);
 560	if (err) {
 561		ret = vmf_fs_error(err);
 562		goto out_uninit;
 563	}
 564	ret = filemap_fault(vmf);
 565	gfs2_glock_dq(&gh);
 566out_uninit:
 567	gfs2_holder_uninit(&gh);
 
 
 
 
 568	return ret;
 569}
 570
 571static const struct vm_operations_struct gfs2_vm_ops = {
 572	.fault = gfs2_fault,
 573	.map_pages = filemap_map_pages,
 574	.page_mkwrite = gfs2_page_mkwrite,
 575};
 576
 577/**
 578 * gfs2_mmap
 579 * @file: The file to map
 580 * @vma: The VMA which described the mapping
 581 *
 582 * There is no need to get a lock here unless we should be updating
 583 * atime. We ignore any locking errors since the only consequence is
 584 * a missed atime update (which will just be deferred until later).
 585 *
 586 * Returns: 0
 587 */
 588
 589static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
 590{
 591	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 592
 593	if (!(file->f_flags & O_NOATIME) &&
 594	    !IS_NOATIME(&ip->i_inode)) {
 595		struct gfs2_holder i_gh;
 596		int error;
 597
 598		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 599					   &i_gh);
 
 
 
 
 
 600		if (error)
 601			return error;
 602		/* grab lock to update inode */
 603		gfs2_glock_dq_uninit(&i_gh);
 604		file_accessed(file);
 605	}
 606	vma->vm_ops = &gfs2_vm_ops;
 
 607
 608	return 0;
 609}
 610
 611/**
 612 * gfs2_open_common - This is common to open and atomic_open
 613 * @inode: The inode being opened
 614 * @file: The file being opened
 615 *
 616 * This maybe called under a glock or not depending upon how it has
 617 * been called. We must always be called under a glock for regular
 618 * files, however. For other file types, it does not matter whether
 619 * we hold the glock or not.
 620 *
 621 * Returns: Error code or 0 for success
 622 */
 623
 624int gfs2_open_common(struct inode *inode, struct file *file)
 625{
 
 
 626	struct gfs2_file *fp;
 627	int ret;
 628
 629	if (S_ISREG(inode->i_mode)) {
 630		ret = generic_file_open(inode, file);
 631		if (ret)
 632			return ret;
 633
 634		if (!gfs2_is_jdata(GFS2_I(inode)))
 635			file->f_mode |= FMODE_CAN_ODIRECT;
 636	}
 637
 638	fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
 639	if (!fp)
 640		return -ENOMEM;
 641
 642	mutex_init(&fp->f_fl_mutex);
 643
 644	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
 645	file->private_data = fp;
 646	if (file->f_mode & FMODE_WRITE) {
 647		ret = gfs2_qa_get(GFS2_I(inode));
 648		if (ret)
 649			goto fail;
 650	}
 651	return 0;
 652
 653fail:
 654	kfree(file->private_data);
 655	file->private_data = NULL;
 656	return ret;
 657}
 658
 659/**
 660 * gfs2_open - open a file
 661 * @inode: the inode to open
 662 * @file: the struct file for this opening
 663 *
 664 * After atomic_open, this function is only used for opening files
 665 * which are already cached. We must still get the glock for regular
 666 * files to ensure that we have the file size uptodate for the large
 667 * file check which is in the common code. That is only an issue for
 668 * regular files though.
 669 *
 670 * Returns: errno
 671 */
 672
 673static int gfs2_open(struct inode *inode, struct file *file)
 674{
 675	struct gfs2_inode *ip = GFS2_I(inode);
 676	struct gfs2_holder i_gh;
 677	int error;
 678	bool need_unlock = false;
 679
 680	if (S_ISREG(ip->i_inode.i_mode)) {
 681		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
 682					   &i_gh);
 683		if (error)
 684			return error;
 685		need_unlock = true;
 686	}
 687
 688	error = gfs2_open_common(inode, file);
 
 
 
 
 689
 690	if (need_unlock)
 691		gfs2_glock_dq_uninit(&i_gh);
 
 
 
 692
 
 
 
 
 
 693	return error;
 694}
 695
 696/**
 697 * gfs2_release - called to close a struct file
 698 * @inode: the inode the struct file belongs to
 699 * @file: the struct file being closed
 700 *
 701 * Returns: errno
 702 */
 703
 704static int gfs2_release(struct inode *inode, struct file *file)
 705{
 706	struct gfs2_inode *ip = GFS2_I(inode);
 
 707
 708	kfree(file->private_data);
 709	file->private_data = NULL;
 710
 711	if (file->f_mode & FMODE_WRITE) {
 712		if (gfs2_rs_active(&ip->i_res))
 713			gfs2_rs_delete(ip);
 714		gfs2_qa_put(ip);
 715	}
 716	return 0;
 717}
 718
 719/**
 720 * gfs2_fsync - sync the dirty data for a file (across the cluster)
 721 * @file: the file that points to the dentry
 722 * @start: the start position in the file to sync
 723 * @end: the end position in the file to sync
 724 * @datasync: set if we can ignore timestamp changes
 725 *
 726 * We split the data flushing here so that we don't wait for the data
 727 * until after we've also sent the metadata to disk. Note that for
 728 * data=ordered, we will write & wait for the data at the log flush
 729 * stage anyway, so this is unlikely to make much of a difference
 730 * except in the data=writeback case.
 731 *
 732 * If the fdatawrite fails due to any reason except -EIO, we will
 733 * continue the remainder of the fsync, although we'll still report
 734 * the error at the end. This is to match filemap_write_and_wait_range()
 735 * behaviour.
 736 *
 737 * Returns: errno
 738 */
 739
 740static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 741		      int datasync)
 742{
 743	struct address_space *mapping = file->f_mapping;
 744	struct inode *inode = mapping->host;
 745	int sync_state = inode->i_state & I_DIRTY;
 746	struct gfs2_inode *ip = GFS2_I(inode);
 747	int ret = 0, ret1 = 0;
 748
 749	if (mapping->nrpages) {
 750		ret1 = filemap_fdatawrite_range(mapping, start, end);
 751		if (ret1 == -EIO)
 752			return ret1;
 753	}
 754
 755	if (!gfs2_is_jdata(ip))
 756		sync_state &= ~I_DIRTY_PAGES;
 757	if (datasync)
 758		sync_state &= ~I_DIRTY_SYNC;
 759
 760	if (sync_state) {
 761		ret = sync_inode_metadata(inode, 1);
 762		if (ret)
 763			return ret;
 764		if (gfs2_is_jdata(ip))
 765			ret = file_write_and_wait(file);
 766		if (ret)
 767			return ret;
 768		gfs2_ail_flush(ip->i_gl, 1);
 769	}
 770
 771	if (mapping->nrpages)
 772		ret = file_fdatawait_range(file, start, end);
 773
 774	return ret ? ret : ret1;
 775}
 776
 777static inline bool should_fault_in_pages(struct iov_iter *i,
 778					 struct kiocb *iocb,
 779					 size_t *prev_count,
 780					 size_t *window_size)
 781{
 782	size_t count = iov_iter_count(i);
 783	size_t size, offs;
 784
 785	if (!count)
 786		return false;
 787	if (!user_backed_iter(i))
 788		return false;
 789
 790	/*
 791	 * Try to fault in multiple pages initially.  When that doesn't result
 792	 * in any progress, fall back to a single page.
 793	 */
 794	size = PAGE_SIZE;
 795	offs = offset_in_page(iocb->ki_pos);
 796	if (*prev_count != count) {
 797		size_t nr_dirtied;
 798
 799		nr_dirtied = max(current->nr_dirtied_pause -
 800				 current->nr_dirtied, 8);
 801		size = min_t(size_t, SZ_1M, nr_dirtied << PAGE_SHIFT);
 802	}
 803
 804	*prev_count = count;
 805	*window_size = size - offs;
 806	return true;
 807}
 808
 809static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to,
 810				     struct gfs2_holder *gh)
 811{
 812	struct file *file = iocb->ki_filp;
 813	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
 814	size_t prev_count = 0, window_size = 0;
 815	size_t read = 0;
 816	ssize_t ret;
 817
 818	/*
 819	 * In this function, we disable page faults when we're holding the
 820	 * inode glock while doing I/O.  If a page fault occurs, we indicate
 821	 * that the inode glock may be dropped, fault in the pages manually,
 822	 * and retry.
 823	 *
 824	 * Unlike generic_file_read_iter, for reads, iomap_dio_rw can trigger
 825	 * physical as well as manual page faults, and we need to disable both
 826	 * kinds.
 827	 *
 828	 * For direct I/O, gfs2 takes the inode glock in deferred mode.  This
 829	 * locking mode is compatible with other deferred holders, so multiple
 830	 * processes and nodes can do direct I/O to a file at the same time.
 831	 * There's no guarantee that reads or writes will be atomic.  Any
 832	 * coordination among readers and writers needs to happen externally.
 833	 */
 834
 835	if (!iov_iter_count(to))
 836		return 0; /* skip atime */
 837
 838	gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh);
 839retry:
 840	ret = gfs2_glock_nq(gh);
 841	if (ret)
 842		goto out_uninit;
 843	pagefault_disable();
 844	to->nofault = true;
 845	ret = iomap_dio_rw(iocb, to, &gfs2_iomap_ops, NULL,
 846			   IOMAP_DIO_PARTIAL, NULL, read);
 847	to->nofault = false;
 848	pagefault_enable();
 849	if (ret <= 0 && ret != -EFAULT)
 850		goto out_unlock;
 851	/* No increment (+=) because iomap_dio_rw returns a cumulative value. */
 852	if (ret > 0)
 853		read = ret;
 854
 855	if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) {
 856		gfs2_glock_dq(gh);
 857		window_size -= fault_in_iov_iter_writeable(to, window_size);
 858		if (window_size)
 859			goto retry;
 860	}
 861out_unlock:
 862	if (gfs2_holder_queued(gh))
 863		gfs2_glock_dq(gh);
 864out_uninit:
 865	gfs2_holder_uninit(gh);
 866	/* User space doesn't expect partial success. */
 867	if (ret < 0)
 868		return ret;
 869	return read;
 870}
 871
 872static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from,
 873				      struct gfs2_holder *gh)
 874{
 875	struct file *file = iocb->ki_filp;
 876	struct inode *inode = file->f_mapping->host;
 877	struct gfs2_inode *ip = GFS2_I(inode);
 878	size_t prev_count = 0, window_size = 0;
 879	size_t written = 0;
 880	bool enough_retries;
 881	ssize_t ret;
 882
 883	/*
 884	 * In this function, we disable page faults when we're holding the
 885	 * inode glock while doing I/O.  If a page fault occurs, we indicate
 886	 * that the inode glock may be dropped, fault in the pages manually,
 887	 * and retry.
 888	 *
 889	 * For writes, iomap_dio_rw only triggers manual page faults, so we
 890	 * don't need to disable physical ones.
 891	 */
 892
 893	/*
 894	 * Deferred lock, even if its a write, since we do no allocation on
 895	 * this path. All we need to change is the atime, and this lock mode
 896	 * ensures that other nodes have flushed their buffered read caches
 897	 * (i.e. their page cache entries for this inode). We do not,
 898	 * unfortunately, have the option of only flushing a range like the
 899	 * VFS does.
 900	 */
 901	gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, gh);
 902retry:
 903	ret = gfs2_glock_nq(gh);
 904	if (ret)
 905		goto out_uninit;
 906	/* Silently fall back to buffered I/O when writing beyond EOF */
 907	if (iocb->ki_pos + iov_iter_count(from) > i_size_read(&ip->i_inode))
 908		goto out_unlock;
 909
 910	from->nofault = true;
 911	ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL,
 912			   IOMAP_DIO_PARTIAL, NULL, written);
 913	from->nofault = false;
 914	if (ret <= 0) {
 915		if (ret == -ENOTBLK)
 916			ret = 0;
 917		if (ret != -EFAULT)
 918			goto out_unlock;
 919	}
 920	/* No increment (+=) because iomap_dio_rw returns a cumulative value. */
 921	if (ret > 0)
 922		written = ret;
 923
 924	enough_retries = prev_count == iov_iter_count(from) &&
 925			 window_size <= PAGE_SIZE;
 926	if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
 927		gfs2_glock_dq(gh);
 928		window_size -= fault_in_iov_iter_readable(from, window_size);
 929		if (window_size) {
 930			if (!enough_retries)
 931				goto retry;
 932			/* fall back to buffered I/O */
 933			ret = 0;
 934		}
 935	}
 936out_unlock:
 937	if (gfs2_holder_queued(gh))
 938		gfs2_glock_dq(gh);
 939out_uninit:
 940	gfs2_holder_uninit(gh);
 941	/* User space doesn't expect partial success. */
 942	if (ret < 0)
 943		return ret;
 944	return written;
 945}
 946
 947static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 948{
 949	struct gfs2_inode *ip;
 950	struct gfs2_holder gh;
 951	size_t prev_count = 0, window_size = 0;
 952	size_t read = 0;
 953	ssize_t ret;
 954
 955	/*
 956	 * In this function, we disable page faults when we're holding the
 957	 * inode glock while doing I/O.  If a page fault occurs, we indicate
 958	 * that the inode glock may be dropped, fault in the pages manually,
 959	 * and retry.
 960	 */
 961
 962	if (iocb->ki_flags & IOCB_DIRECT)
 963		return gfs2_file_direct_read(iocb, to, &gh);
 964
 965	pagefault_disable();
 966	iocb->ki_flags |= IOCB_NOIO;
 967	ret = generic_file_read_iter(iocb, to);
 968	iocb->ki_flags &= ~IOCB_NOIO;
 969	pagefault_enable();
 970	if (ret >= 0) {
 971		if (!iov_iter_count(to))
 972			return ret;
 973		read = ret;
 974	} else if (ret != -EFAULT) {
 975		if (ret != -EAGAIN)
 976			return ret;
 977		if (iocb->ki_flags & IOCB_NOWAIT)
 978			return ret;
 979	}
 980	ip = GFS2_I(iocb->ki_filp->f_mapping->host);
 981	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 982retry:
 983	ret = gfs2_glock_nq(&gh);
 984	if (ret)
 985		goto out_uninit;
 986	pagefault_disable();
 987	ret = generic_file_read_iter(iocb, to);
 988	pagefault_enable();
 989	if (ret <= 0 && ret != -EFAULT)
 990		goto out_unlock;
 991	if (ret > 0)
 992		read += ret;
 993
 994	if (should_fault_in_pages(to, iocb, &prev_count, &window_size)) {
 995		gfs2_glock_dq(&gh);
 996		window_size -= fault_in_iov_iter_writeable(to, window_size);
 997		if (window_size)
 998			goto retry;
 999	}
1000out_unlock:
1001	if (gfs2_holder_queued(&gh))
1002		gfs2_glock_dq(&gh);
1003out_uninit:
1004	gfs2_holder_uninit(&gh);
1005	return read ? read : ret;
1006}
1007
1008static ssize_t gfs2_file_buffered_write(struct kiocb *iocb,
1009					struct iov_iter *from,
1010					struct gfs2_holder *gh)
1011{
1012	struct file *file = iocb->ki_filp;
1013	struct inode *inode = file_inode(file);
1014	struct gfs2_inode *ip = GFS2_I(inode);
1015	struct gfs2_sbd *sdp = GFS2_SB(inode);
1016	struct gfs2_holder *statfs_gh = NULL;
1017	size_t prev_count = 0, window_size = 0;
1018	size_t orig_count = iov_iter_count(from);
1019	size_t written = 0;
1020	ssize_t ret;
1021
1022	/*
1023	 * In this function, we disable page faults when we're holding the
1024	 * inode glock while doing I/O.  If a page fault occurs, we indicate
1025	 * that the inode glock may be dropped, fault in the pages manually,
1026	 * and retry.
1027	 */
1028
1029	if (inode == sdp->sd_rindex) {
1030		statfs_gh = kmalloc(sizeof(*statfs_gh), GFP_NOFS);
1031		if (!statfs_gh)
1032			return -ENOMEM;
1033	}
1034
1035	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, gh);
1036	if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
1037retry:
1038		window_size -= fault_in_iov_iter_readable(from, window_size);
1039		if (!window_size) {
1040			ret = -EFAULT;
1041			goto out_uninit;
1042		}
1043		from->count = min(from->count, window_size);
1044	}
1045	ret = gfs2_glock_nq(gh);
1046	if (ret)
1047		goto out_uninit;
1048
1049	if (inode == sdp->sd_rindex) {
1050		struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
1051
1052		ret = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
1053					 GL_NOCACHE, statfs_gh);
1054		if (ret)
1055			goto out_unlock;
1056	}
1057
1058	pagefault_disable();
1059	ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops);
1060	pagefault_enable();
1061	if (ret > 0)
1062		written += ret;
1063
1064	if (inode == sdp->sd_rindex)
1065		gfs2_glock_dq_uninit(statfs_gh);
1066
1067	if (ret <= 0 && ret != -EFAULT)
1068		goto out_unlock;
1069
1070	from->count = orig_count - written;
1071	if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) {
1072		gfs2_glock_dq(gh);
1073		goto retry;
1074	}
1075out_unlock:
1076	if (gfs2_holder_queued(gh))
1077		gfs2_glock_dq(gh);
1078out_uninit:
1079	gfs2_holder_uninit(gh);
1080	kfree(statfs_gh);
1081	from->count = orig_count - written;
1082	return written ? written : ret;
1083}
1084
1085/**
1086 * gfs2_file_write_iter - Perform a write to a file
1087 * @iocb: The io context
1088 * @from: The data to write
 
 
1089 *
1090 * We have to do a lock/unlock here to refresh the inode size for
1091 * O_APPEND writes, otherwise we can land up writing at the wrong
1092 * offset. There is still a race, but provided the app is using its
1093 * own file locking, this will make O_APPEND work as expected.
1094 *
1095 */
1096
1097static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
1098{
1099	struct file *file = iocb->ki_filp;
1100	struct inode *inode = file_inode(file);
1101	struct gfs2_inode *ip = GFS2_I(inode);
1102	struct gfs2_holder gh;
1103	ssize_t ret;
1104
1105	gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));
 
 
 
 
1106
1107	if (iocb->ki_flags & IOCB_APPEND) {
1108		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
1109		if (ret)
1110			return ret;
1111		gfs2_glock_dq_uninit(&gh);
1112	}
1113
1114	inode_lock(inode);
1115	ret = generic_write_checks(iocb, from);
1116	if (ret <= 0)
1117		goto out_unlock;
 
 
 
 
 
 
 
 
 
 
1118
1119	ret = file_remove_privs(file);
1120	if (ret)
1121		goto out_unlock;
1122
1123	if (iocb->ki_flags & IOCB_DIRECT) {
1124		struct address_space *mapping = file->f_mapping;
1125		ssize_t buffered, ret2;
1126
1127		/*
1128		 * Note that under direct I/O, we don't allow and inode
1129		 * timestamp updates, so we're not calling file_update_time()
1130		 * here.
1131		 */
1132
1133		ret = gfs2_file_direct_write(iocb, from, &gh);
1134		if (ret < 0 || !iov_iter_count(from))
1135			goto out_unlock;
 
 
 
 
 
 
 
 
 
1136
1137		iocb->ki_flags |= IOCB_DSYNC;
1138		buffered = gfs2_file_buffered_write(iocb, from, &gh);
1139		if (unlikely(buffered <= 0)) {
1140			if (!ret)
1141				ret = buffered;
1142			goto out_unlock;
 
1143		}
 
 
 
 
 
 
 
 
 
 
1144
1145		/*
1146		 * We need to ensure that the page cache pages are written to
1147		 * disk and invalidated to preserve the expected O_DIRECT
1148		 * semantics.  If the writeback or invalidate fails, only report
1149		 * the direct I/O range as we don't know if the buffered pages
1150		 * made it to disk.
1151		 */
1152		ret2 = generic_write_sync(iocb, buffered);
1153		invalidate_mapping_pages(mapping,
1154				(iocb->ki_pos - buffered) >> PAGE_SHIFT,
1155				(iocb->ki_pos - 1) >> PAGE_SHIFT);
1156		if (!ret || ret2 > 0)
1157			ret += ret2;
1158	} else {
1159		ret = file_update_time(file);
1160		if (ret)
1161			goto out_unlock;
1162
1163		ret = gfs2_file_buffered_write(iocb, from, &gh);
1164		if (likely(ret > 0))
1165			ret = generic_write_sync(iocb, ret);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1166	}
1167
1168out_unlock:
1169	inode_unlock(inode);
1170	return ret;
1171}
1172
1173static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
1174			   int mode)
1175{
1176	struct super_block *sb = inode->i_sb;
1177	struct gfs2_inode *ip = GFS2_I(inode);
1178	loff_t end = offset + len;
1179	struct buffer_head *dibh;
1180	int error;
 
 
 
 
 
 
 
 
 
 
1181
1182	error = gfs2_meta_inode_buffer(ip, &dibh);
1183	if (unlikely(error))
1184		return error;
1185
1186	gfs2_trans_add_meta(ip->i_gl, dibh);
1187
1188	if (gfs2_is_stuffed(ip)) {
1189		error = gfs2_unstuff_dinode(ip);
1190		if (unlikely(error))
1191			goto out;
1192	}
1193
1194	while (offset < end) {
1195		struct iomap iomap = { };
 
 
 
 
 
 
 
 
 
1196
1197		error = gfs2_iomap_alloc(inode, offset, end - offset, &iomap);
 
 
 
 
 
 
 
 
1198		if (error)
1199			goto out;
1200		offset = iomap.offset + iomap.length;
1201		if (!(iomap.flags & IOMAP_F_NEW))
1202			continue;
1203		error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits,
1204					 iomap.length >> inode->i_blkbits,
1205					 GFP_NOFS);
1206		if (error) {
1207			fs_err(GFS2_SB(inode), "Failed to zero data buffers\n");
1208			goto out;
1209		}
1210	}
 
 
 
 
 
 
1211out:
1212	brelse(dibh);
1213	return error;
1214}
1215
1216/**
1217 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
1218 *                     blocks, determine how many bytes can be written.
1219 * @ip:          The inode in question.
1220 * @len:         Max cap of bytes. What we return in *len must be <= this.
1221 * @data_blocks: Compute and return the number of data blocks needed
1222 * @ind_blocks:  Compute and return the number of indirect blocks needed
1223 * @max_blocks:  The total blocks available to work with.
1224 *
1225 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
1226 */
1227static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
1228			    unsigned int *data_blocks, unsigned int *ind_blocks,
1229			    unsigned int max_blocks)
1230{
1231	loff_t max = *len;
1232	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 
1233	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
1234
1235	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
1236		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
1237		max_data -= tmp;
1238	}
1239
 
 
 
1240	*data_blocks = max_data;
1241	*ind_blocks = max_blocks - max_data;
1242	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
1243	if (*len > max) {
1244		*len = max;
1245		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
1246	}
1247}
1248
1249static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 
1250{
1251	struct inode *inode = file_inode(file);
1252	struct gfs2_sbd *sdp = GFS2_SB(inode);
1253	struct gfs2_inode *ip = GFS2_I(inode);
1254	struct gfs2_alloc_parms ap = {};
1255	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
1256	loff_t bytes, max_bytes, max_blks;
 
1257	int error;
1258	const loff_t pos = offset;
1259	const loff_t count = len;
1260	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
1261	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
1262	loff_t max_chunk_size = UINT_MAX & bsize_mask;
1263
1264	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
 
 
1265
1266	offset &= bsize_mask;
1267
1268	len = next - offset;
1269	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
1270	if (!bytes)
1271		bytes = UINT_MAX;
1272	bytes &= bsize_mask;
1273	if (bytes == 0)
1274		bytes = sdp->sd_sb.sb_bsize;
1275
1276	gfs2_size_hint(file, offset, len);
 
 
 
1277
1278	gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
1279	ap.min_target = data_blocks + ind_blocks;
1280
1281	while (len > 0) {
1282		if (len < bytes)
1283			bytes = len;
1284		if (!gfs2_write_alloc_required(ip, offset, bytes)) {
1285			len -= bytes;
1286			offset += bytes;
1287			continue;
1288		}
1289
1290		/* We need to determine how many bytes we can actually
1291		 * fallocate without exceeding quota or going over the
1292		 * end of the fs. We start off optimistically by assuming
1293		 * we can write max_bytes */
1294		max_bytes = (len > max_chunk_size) ? max_chunk_size : len;
1295
1296		/* Since max_bytes is most likely a theoretical max, we
1297		 * calculate a more realistic 'bytes' to serve as a good
1298		 * starting point for the number of bytes we may be able
1299		 * to write */
1300		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
1301		ap.target = data_blocks + ind_blocks;
1302
1303		error = gfs2_quota_lock_check(ip, &ap);
1304		if (error)
1305			return error;
1306		/* ap.allowed tells us how many blocks quota will allow
1307		 * us to write. Check if this reduces max_blks */
1308		max_blks = UINT_MAX;
1309		if (ap.allowed)
1310			max_blks = ap.allowed;
1311
1312		error = gfs2_inplace_reserve(ip, &ap);
1313		if (error)
1314			goto out_qunlock;
1315
1316		/* check if the selected rgrp limits our max_blks further */
1317		if (ip->i_res.rs_reserved < max_blks)
1318			max_blks = ip->i_res.rs_reserved;
1319
1320		/* Almost done. Calculate bytes that can be written using
1321		 * max_blks. We also recompute max_bytes, data_blocks and
1322		 * ind_blocks */
1323		calc_max_reserv(ip, &max_bytes, &data_blocks,
1324				&ind_blocks, max_blks);
1325
1326		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
1327			  RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
1328		if (gfs2_is_jdata(ip))
1329			rblocks += data_blocks ? data_blocks : 1;
1330
1331		error = gfs2_trans_begin(sdp, rblocks,
1332					 PAGE_SIZE >> inode->i_blkbits);
1333		if (error)
1334			goto out_trans_fail;
1335
1336		error = fallocate_chunk(inode, offset, max_bytes, mode);
1337		gfs2_trans_end(sdp);
1338
1339		if (error)
1340			goto out_trans_fail;
1341
1342		len -= max_bytes;
1343		offset += max_bytes;
1344		gfs2_inplace_release(ip);
1345		gfs2_quota_unlock(ip);
 
1346	}
1347
1348	if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size)
1349		i_size_write(inode, pos + count);
1350	file_update_time(file);
1351	mark_inode_dirty(inode);
1352
1353	if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
1354		return vfs_fsync_range(file, pos, pos + count - 1,
1355			       (file->f_flags & __O_SYNC) ? 0 : 1);
1356	return 0;
1357
1358out_trans_fail:
1359	gfs2_inplace_release(ip);
1360out_qunlock:
1361	gfs2_quota_unlock(ip);
 
 
 
 
 
 
1362	return error;
1363}
1364
1365static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
1366{
1367	struct inode *inode = file_inode(file);
1368	struct gfs2_sbd *sdp = GFS2_SB(inode);
1369	struct gfs2_inode *ip = GFS2_I(inode);
1370	struct gfs2_holder gh;
1371	int ret;
1372
1373	if (mode & ~(FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))
1374		return -EOPNOTSUPP;
1375	/* fallocate is needed by gfs2_grow to reserve space in the rindex */
1376	if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex)
1377		return -EOPNOTSUPP;
1378
1379	inode_lock(inode);
 
 
 
 
 
 
 
1380
1381	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1382	ret = gfs2_glock_nq(&gh);
1383	if (ret)
1384		goto out_uninit;
1385
1386	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
1387	    (offset + len) > inode->i_size) {
1388		ret = inode_newsize_ok(inode, offset + len);
1389		if (ret)
1390			goto out_unlock;
1391	}
1392
1393	ret = get_write_access(inode);
1394	if (ret)
1395		goto out_unlock;
1396
1397	if (mode & FALLOC_FL_PUNCH_HOLE) {
1398		ret = __gfs2_punch_hole(file, offset, len);
1399	} else {
1400		ret = __gfs2_fallocate(file, mode, offset, len);
1401		if (ret)
1402			gfs2_rs_deltree(&ip->i_res);
1403	}
1404
1405	put_write_access(inode);
1406out_unlock:
1407	gfs2_glock_dq(&gh);
1408out_uninit:
1409	gfs2_holder_uninit(&gh);
1410	inode_unlock(inode);
1411	return ret;
1412}
1413
1414static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
1415				      struct file *out, loff_t *ppos,
1416				      size_t len, unsigned int flags)
1417{
1418	ssize_t ret;
1419
1420	gfs2_size_hint(out, *ppos, len);
1421
1422	ret = iter_file_splice_write(pipe, out, ppos, len, flags);
1423	return ret;
1424}
1425
1426#ifdef CONFIG_GFS2_FS_LOCKING_DLM
1427
1428/**
1429 * gfs2_lock - acquire/release a posix lock on a file
1430 * @file: the file pointer
1431 * @cmd: either modify or retrieve lock state, possibly wait
1432 * @fl: type and range of lock
1433 *
1434 * Returns: errno
1435 */
1436
1437static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
1438{
1439	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
1440	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
1441	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1442
1443	if (!(fl->fl_flags & FL_POSIX))
1444		return -ENOLCK;
1445	if (gfs2_withdrawing_or_withdrawn(sdp)) {
1446		if (fl->fl_type == F_UNLCK)
1447			locks_lock_file_wait(file, fl);
 
 
 
 
 
 
1448		return -EIO;
1449	}
1450	if (cmd == F_CANCELLK)
1451		return dlm_posix_cancel(ls->ls_dlm, ip->i_no_addr, file, fl);
1452	else if (IS_GETLK(cmd))
1453		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
1454	else if (fl->fl_type == F_UNLCK)
1455		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
1456	else
1457		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
1458}
1459
1460static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh)
1461{
1462	struct gfs2_glock *gl = gfs2_glock_hold(fl_gh->gh_gl);
1463
1464	/*
1465	 * Make sure gfs2_glock_put() won't sleep under the file->f_lock
1466	 * spinlock.
1467	 */
1468
1469	spin_lock(&file->f_lock);
1470	gfs2_holder_uninit(fl_gh);
1471	spin_unlock(&file->f_lock);
1472	gfs2_glock_put(gl);
1473}
1474
1475static int do_flock(struct file *file, int cmd, struct file_lock *fl)
1476{
1477	struct gfs2_file *fp = file->private_data;
1478	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1479	struct gfs2_inode *ip = GFS2_I(file_inode(file));
1480	struct gfs2_glock *gl;
1481	unsigned int state;
1482	u16 flags;
1483	int error = 0;
1484	int sleeptime;
1485
1486	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
1487	flags = GL_EXACT | GL_NOPID;
1488	if (!IS_SETLKW(cmd))
1489		flags |= LM_FLAG_TRY_1CB;
1490
1491	mutex_lock(&fp->f_fl_mutex);
1492
1493	if (gfs2_holder_initialized(fl_gh)) {
1494		struct file_lock request;
1495		if (fl_gh->gh_state == state)
1496			goto out;
1497		locks_init_lock(&request);
1498		request.fl_type = F_UNLCK;
1499		request.fl_flags = FL_FLOCK;
1500		locks_lock_file_wait(file, &request);
1501		gfs2_glock_dq(fl_gh);
1502		gfs2_holder_reinit(state, flags, fl_gh);
1503	} else {
1504		error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
1505				       &gfs2_flock_glops, CREATE, &gl);
1506		if (error)
1507			goto out;
1508		spin_lock(&file->f_lock);
1509		gfs2_holder_init(gl, state, flags, fl_gh);
1510		spin_unlock(&file->f_lock);
1511		gfs2_glock_put(gl);
1512	}
1513	for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) {
1514		error = gfs2_glock_nq(fl_gh);
1515		if (error != GLR_TRYFAILED)
1516			break;
1517		fl_gh->gh_flags &= ~LM_FLAG_TRY_1CB;
1518		fl_gh->gh_flags |= LM_FLAG_TRY;
1519		msleep(sleeptime);
1520	}
1521	if (error) {
1522		__flock_holder_uninit(file, fl_gh);
1523		if (error == GLR_TRYFAILED)
1524			error = -EAGAIN;
1525	} else {
1526		error = locks_lock_file_wait(file, fl);
1527		gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
1528	}
1529
1530out:
1531	mutex_unlock(&fp->f_fl_mutex);
1532	return error;
1533}
1534
1535static void do_unflock(struct file *file, struct file_lock *fl)
1536{
1537	struct gfs2_file *fp = file->private_data;
1538	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
1539
1540	mutex_lock(&fp->f_fl_mutex);
1541	locks_lock_file_wait(file, fl);
1542	if (gfs2_holder_initialized(fl_gh)) {
1543		gfs2_glock_dq(fl_gh);
1544		__flock_holder_uninit(file, fl_gh);
1545	}
1546	mutex_unlock(&fp->f_fl_mutex);
1547}
1548
1549/**
1550 * gfs2_flock - acquire/release a flock lock on a file
1551 * @file: the file pointer
1552 * @cmd: either modify or retrieve lock state, possibly wait
1553 * @fl: type and range of lock
1554 *
1555 * Returns: errno
1556 */
1557
1558static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
1559{
1560	if (!(fl->fl_flags & FL_FLOCK))
1561		return -ENOLCK;
 
 
1562
1563	if (fl->fl_type == F_UNLCK) {
1564		do_unflock(file, fl);
1565		return 0;
1566	} else {
1567		return do_flock(file, cmd, fl);
1568	}
1569}
1570
1571const struct file_operations gfs2_file_fops = {
1572	.llseek		= gfs2_llseek,
1573	.read_iter	= gfs2_file_read_iter,
1574	.write_iter	= gfs2_file_write_iter,
1575	.iopoll		= iocb_bio_iopoll,
 
1576	.unlocked_ioctl	= gfs2_ioctl,
1577	.compat_ioctl	= gfs2_compat_ioctl,
1578	.mmap		= gfs2_mmap,
1579	.open		= gfs2_open,
1580	.release	= gfs2_release,
1581	.fsync		= gfs2_fsync,
1582	.lock		= gfs2_lock,
1583	.flock		= gfs2_flock,
1584	.splice_read	= copy_splice_read,
1585	.splice_write	= gfs2_file_splice_write,
1586	.setlease	= simple_nosetlease,
1587	.fallocate	= gfs2_fallocate,
1588};
1589
1590const struct file_operations gfs2_dir_fops = {
1591	.iterate_shared	= gfs2_readdir,
1592	.unlocked_ioctl	= gfs2_ioctl,
1593	.compat_ioctl	= gfs2_compat_ioctl,
1594	.open		= gfs2_open,
1595	.release	= gfs2_release,
1596	.fsync		= gfs2_fsync,
1597	.lock		= gfs2_lock,
1598	.flock		= gfs2_flock,
1599	.llseek		= default_llseek,
1600};
1601
1602#endif /* CONFIG_GFS2_FS_LOCKING_DLM */
1603
1604const struct file_operations gfs2_file_fops_nolock = {
1605	.llseek		= gfs2_llseek,
1606	.read_iter	= gfs2_file_read_iter,
1607	.write_iter	= gfs2_file_write_iter,
1608	.iopoll		= iocb_bio_iopoll,
 
1609	.unlocked_ioctl	= gfs2_ioctl,
1610	.compat_ioctl	= gfs2_compat_ioctl,
1611	.mmap		= gfs2_mmap,
1612	.open		= gfs2_open,
1613	.release	= gfs2_release,
1614	.fsync		= gfs2_fsync,
1615	.splice_read	= copy_splice_read,
1616	.splice_write	= gfs2_file_splice_write,
1617	.setlease	= generic_setlease,
1618	.fallocate	= gfs2_fallocate,
1619};
1620
1621const struct file_operations gfs2_dir_fops_nolock = {
1622	.iterate_shared	= gfs2_readdir,
1623	.unlocked_ioctl	= gfs2_ioctl,
1624	.compat_ioctl	= gfs2_compat_ioctl,
1625	.open		= gfs2_open,
1626	.release	= gfs2_release,
1627	.fsync		= gfs2_fsync,
1628	.llseek		= default_llseek,
1629};
1630