fallocate should be a file operation

Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Documentation/filesystems/Locking

@@ -60,7 +60,6 @@ ata *);
 	ssize_t (*listxattr) (struct dentry *, char *, size_t);
 	int (*removexattr) (struct dentry *, const char *);
 	void (*truncate_range)(struct inode *, loff_t, loff_t);
-	long (*fallocate)(struct inode *inode, int mode, loff_t offset, loff_t len);
 	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);
 
 locking rules:
@@ -88,7 +87,6 @@ getxattr:	no
 listxattr:	no
 removexattr:	yes
 truncate_range:	yes
-fallocate:	no
 fiemap:		no
 	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
 victim.
@@ -437,6 +435,7 @@ prototypes:
 	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *,
 			size_t, unsigned int);
 	int (*setlease)(struct file *, long, struct file_lock **);
+	long (*fallocate)(struct file *, int, loff_t, loff_t);
 };
 
 locking rules:

fs/btrfs/file.c

@@ -24,6 +24,7 @@
 #include <linux/string.h>
 #include <linux/backing-dev.h>
 #include <linux/mpage.h>
+#include <linux/falloc.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
 #include <linux/statfs.h>
@@ -1237,6 +1238,117 @@ static int btrfs_file_mmap(struct file	*filp, struct vm_area_struct *vma)
 	return 0;
 }
 
+static long btrfs_fallocate(struct file *file, int mode,
+			    loff_t offset, loff_t len)
+{
+	struct inode *inode = file->f_path.dentry->d_inode;
+	struct extent_state *cached_state = NULL;
+	u64 cur_offset;
+	u64 last_byte;
+	u64 alloc_start;
+	u64 alloc_end;
+	u64 alloc_hint = 0;
+	u64 locked_end;
+	u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
+	struct extent_map *em;
+	int ret;
+
+	alloc_start = offset & ~mask;
+	alloc_end =  (offset + len + mask) & ~mask;
+
+	/* We only support the FALLOC_FL_KEEP_SIZE mode */
+	if (mode & ~FALLOC_FL_KEEP_SIZE)
+		return -EOPNOTSUPP;
+
+	/*
+	 * wait for ordered IO before we have any locks.  We'll loop again
+	 * below with the locks held.
+	 */
+	btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
+
+	mutex_lock(&inode->i_mutex);
+	ret = inode_newsize_ok(inode, alloc_end);
+	if (ret)
+		goto out;
+
+	if (alloc_start > inode->i_size) {
+		ret = btrfs_cont_expand(inode, alloc_start);
+		if (ret)
+			goto out;
+	}
+
+	ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start);
+	if (ret)
+		goto out;
+
+	locked_end = alloc_end - 1;
+	while (1) {
+		struct btrfs_ordered_extent *ordered;
+
+		/* the extent lock is ordered inside the running
+		 * transaction
+		 */
+		lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
+				 locked_end, 0, &cached_state, GFP_NOFS);
+		ordered = btrfs_lookup_first_ordered_extent(inode,
+							    alloc_end - 1);
+		if (ordered &&
+		    ordered->file_offset + ordered->len > alloc_start &&
+		    ordered->file_offset < alloc_end) {
+			btrfs_put_ordered_extent(ordered);
+			unlock_extent_cached(&BTRFS_I(inode)->io_tree,
+					     alloc_start, locked_end,
+					     &cached_state, GFP_NOFS);
+			/*
+			 * we can't wait on the range with the transaction
+			 * running or with the extent lock held
+			 */
+			btrfs_wait_ordered_range(inode, alloc_start,
+						 alloc_end - alloc_start);
+		} else {
+			if (ordered)
+				btrfs_put_ordered_extent(ordered);
+			break;
+		}
+	}
+
+	cur_offset = alloc_start;
+	while (1) {
+		em = btrfs_get_extent(inode, NULL, 0, cur_offset,
+				      alloc_end - cur_offset, 0);
+		BUG_ON(IS_ERR(em) || !em);
+		last_byte = min(extent_map_end(em), alloc_end);
+		last_byte = (last_byte + mask) & ~mask;
+		if (em->block_start == EXTENT_MAP_HOLE ||
+		    (cur_offset >= inode->i_size &&
+		     !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
+			ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
+							last_byte - cur_offset,
+							1 << inode->i_blkbits,
+							offset + len,
+							&alloc_hint);
+			if (ret < 0) {
+				free_extent_map(em);
+				break;
+			}
+		}
+		free_extent_map(em);
+
+		cur_offset = last_byte;
+		if (cur_offset >= alloc_end) {
+			ret = 0;
+			break;
+		}
+	}
+	unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
+			     &cached_state, GFP_NOFS);
+
+	btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
+out:
+	mutex_unlock(&inode->i_mutex);
+	return ret;
+}
+
 const struct file_operations btrfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
@@ -1248,6 +1360,7 @@ const struct file_operations btrfs_file_operations = {
 	.open		= generic_file_open,
 	.release	= btrfs_release_file,
 	.fsync		= btrfs_sync_file,
+	.fallocate	= btrfs_fallocate,
 	.unlocked_ioctl	= btrfs_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= btrfs_ioctl,

fs/btrfs/inode.c

@@ -7098,116 +7098,6 @@ int btrfs_prealloc_file_range_trans(struct inode *inode,
 					   min_size, actual_len, alloc_hint, trans);
 }
 
-static long btrfs_fallocate(struct inode *inode, int mode,
-			    loff_t offset, loff_t len)
-{
-	struct extent_state *cached_state = NULL;
-	u64 cur_offset;
-	u64 last_byte;
-	u64 alloc_start;
-	u64 alloc_end;
-	u64 alloc_hint = 0;
-	u64 locked_end;
-	u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
-	struct extent_map *em;
-	int ret;
-
-	alloc_start = offset & ~mask;
-	alloc_end =  (offset + len + mask) & ~mask;
-
-	/* We only support the FALLOC_FL_KEEP_SIZE mode */
-	if (mode & ~FALLOC_FL_KEEP_SIZE)
-		return -EOPNOTSUPP;
-
-	/*
-	 * wait for ordered IO before we have any locks.  We'll loop again
-	 * below with the locks held.
-	 */
-	btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
-
-	mutex_lock(&inode->i_mutex);
-	ret = inode_newsize_ok(inode, alloc_end);
-	if (ret)
-		goto out;
-
-	if (alloc_start > inode->i_size) {
-		ret = btrfs_cont_expand(inode, alloc_start);
-		if (ret)
-			goto out;
-	}
-
-	ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start);
-	if (ret)
-		goto out;
-
-	locked_end = alloc_end - 1;
-	while (1) {
-		struct btrfs_ordered_extent *ordered;
-
-		/* the extent lock is ordered inside the running
-		 * transaction
-		 */
-		lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
-				 locked_end, 0, &cached_state, GFP_NOFS);
-		ordered = btrfs_lookup_first_ordered_extent(inode,
-							    alloc_end - 1);
-		if (ordered &&
-		    ordered->file_offset + ordered->len > alloc_start &&
-		    ordered->file_offset < alloc_end) {
-			btrfs_put_ordered_extent(ordered);
-			unlock_extent_cached(&BTRFS_I(inode)->io_tree,
-					     alloc_start, locked_end,
-					     &cached_state, GFP_NOFS);
-			/*
-			 * we can't wait on the range with the transaction
-			 * running or with the extent lock held
-			 */
-			btrfs_wait_ordered_range(inode, alloc_start,
-						 alloc_end - alloc_start);
-		} else {
-			if (ordered)
-				btrfs_put_ordered_extent(ordered);
-			break;
-		}
-	}
-
-	cur_offset = alloc_start;
-	while (1) {
-		em = btrfs_get_extent(inode, NULL, 0, cur_offset,
-				      alloc_end - cur_offset, 0);
-		BUG_ON(IS_ERR(em) || !em);
-		last_byte = min(extent_map_end(em), alloc_end);
-		last_byte = (last_byte + mask) & ~mask;
-		if (em->block_start == EXTENT_MAP_HOLE ||
-		    (cur_offset >= inode->i_size &&
-		     !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
-			ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
-							last_byte - cur_offset,
-							1 << inode->i_blkbits,
-							offset + len,
-							&alloc_hint);
-			if (ret < 0) {
-				free_extent_map(em);
-				break;
-			}
-		}
-		free_extent_map(em);
-
-		cur_offset = last_byte;
-		if (cur_offset >= alloc_end) {
-			ret = 0;
-			break;
-		}
-	}
-	unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
-			     &cached_state, GFP_NOFS);
-
-	btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
-out:
-	mutex_unlock(&inode->i_mutex);
-	return ret;
-}
-
 static int btrfs_set_page_dirty(struct page *page)
 {
 	return __set_page_dirty_nobuffers(page);
@@ -7310,7 +7200,6 @@ static const struct inode_operations btrfs_file_inode_operations = {
 	.listxattr      = btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 	.permission	= btrfs_permission,
-	.fallocate	= btrfs_fallocate,
 	.fiemap		= btrfs_fiemap,
 };
 static const struct inode_operations btrfs_special_inode_operations = {

fs/ext4/ext4.h

@@ -2065,7 +2065,7 @@ extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 extern void ext4_ext_truncate(struct inode *);
 extern void ext4_ext_init(struct super_block *);
 extern void ext4_ext_release(struct super_block *);
-extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
+extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
 			  loff_t len);
 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
 			  ssize_t len);

fs/ext4/extents.c

@@ -3627,14 +3627,15 @@ static void ext4_falloc_update_inode(struct inode *inode,
 }
 
 /*
- * preallocate space for a file. This implements ext4's fallocate inode
+ * preallocate space for a file. This implements ext4's fallocate file
  * operation, which gets called from sys_fallocate system call.
  * For block-mapped files, posix_fallocate should fall back to the method
  * of writing zeroes to the required new blocks (the same behavior which is
  * expected for file systems which do not support fallocate() system call).
  */
-long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
+long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 {
+	struct inode *inode = file->f_path.dentry->d_inode;
 	handle_t *handle;
 	loff_t new_size;
 	unsigned int max_blocks;
@@ -3655,10 +3656,6 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
 	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
 		return -EOPNOTSUPP;
 
-	/* preallocation to directories is currently not supported */
-	if (S_ISDIR(inode->i_mode))
-		return -ENODEV;
-
 	map.m_lblk = offset >> blkbits;
 	/*
 	 * We can't just convert len to max_blocks because

fs/ext4/file.c

@@ -210,6 +210,7 @@ const struct file_operations ext4_file_operations = {
 	.fsync		= ext4_sync_file,
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= generic_file_splice_write,
+	.fallocate	= ext4_fallocate,
 };
 
 const struct inode_operations ext4_file_inode_operations = {
@@ -223,7 +224,6 @@ const struct inode_operations ext4_file_inode_operations = {
 	.removexattr	= generic_removexattr,
 #endif
 	.check_acl	= ext4_check_acl,
-	.fallocate	= ext4_fallocate,
 	.fiemap		= ext4_fiemap,
 };
 

fs/gfs2/file.c

@@ -19,6 +19,8 @@
 #include <linux/fs.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/ext2_fs.h>
+#include <linux/falloc.h>
+#include <linux/swap.h>
 #include <linux/crc32.h>
 #include <linux/writeback.h>
 #include <asm/uaccess.h>
@@ -610,6 +612,260 @@ static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	return generic_file_aio_write(iocb, iov, nr_segs, pos);
 }
 
+static void empty_write_end(struct page *page, unsigned from,
+			   unsigned to)
+{
+	struct gfs2_inode *ip = GFS2_I(page->mapping->host);
+
+	page_zero_new_buffers(page, from, to);
+	flush_dcache_page(page);
+	mark_page_accessed(page);
+
+	if (!gfs2_is_writeback(ip))
+		gfs2_page_add_databufs(ip, page, from, to);
+
+	block_commit_write(page, from, to);
+}
+
+static int write_empty_blocks(struct page *page, unsigned from, unsigned to)
+{
+	unsigned start, end, next;
+	struct buffer_head *bh, *head;
+	int error;
+
+	if (!page_has_buffers(page)) {
+		error = __block_write_begin(page, from, to - from, gfs2_block_map);
+		if (unlikely(error))
+			return error;
+
+		empty_write_end(page, from, to);
+		return 0;
+	}
+
+	bh = head = page_buffers(page);
+	next = end = 0;
+	while (next < from) {
+		next += bh->b_size;
+		bh = bh->b_this_page;
+	}
+	start = next;
+	do {
+		next += bh->b_size;
+		if (buffer_mapped(bh)) {
+			if (end) {
+				error = __block_write_begin(page, start, end - start,
+							    gfs2_block_map);
+				if (unlikely(error))
+					return error;
+				empty_write_end(page, start, end);
+				end = 0;
+			}
+			start = next;
+		}
+		else
+			end = next;
+		bh = bh->b_this_page;
+	} while (next < to);
+
+	if (end) {
+		error = __block_write_begin(page, start, end - start, gfs2_block_map);
+		if (unlikely(error))
+			return error;
+		empty_write_end(page, start, end);
+	}
+
+	return 0;
+}
+
+static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
+			   int mode)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct buffer_head *dibh;
+	int error;
+	u64 start = offset >> PAGE_CACHE_SHIFT;
+	unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
+	u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
+	pgoff_t curr;
+	struct page *page;
+	unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
+	unsigned int from, to;
+
+	if (!end_offset)
+		end_offset = PAGE_CACHE_SIZE;
+
+	error = gfs2_meta_inode_buffer(ip, &dibh);
+	if (unlikely(error))
+		goto out;
+
+	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
+
+	if (gfs2_is_stuffed(ip)) {
+		error = gfs2_unstuff_dinode(ip, NULL);
+		if (unlikely(error))
+			goto out;
+	}
+
+	curr = start;
+	offset = start << PAGE_CACHE_SHIFT;
+	from = start_offset;
+	to = PAGE_CACHE_SIZE;
+	while (curr <= end) {
+		page = grab_cache_page_write_begin(inode->i_mapping, curr,
+						   AOP_FLAG_NOFS);
+		if (unlikely(!page)) {
+			error = -ENOMEM;
+			goto out;
+		}
+
+		if (curr == end)
+			to = end_offset;
+		error = write_empty_blocks(page, from, to);
+		if (!error && offset + to > inode->i_size &&
+		    !(mode & FALLOC_FL_KEEP_SIZE)) {
+			i_size_write(inode, offset + to);
+		}
+		unlock_page(page);
+		page_cache_release(page);
+		if (error)
+			goto out;
+		curr++;
+		offset += PAGE_CACHE_SIZE;
+		from = 0;
+	}
+
+	gfs2_dinode_out(ip, dibh->b_data);
+	mark_inode_dirty(inode);
+
+	brelse(dibh);
+
+out:
+	return error;
+}
+
+static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
+			    unsigned int *data_blocks, unsigned int *ind_blocks)
+{
+	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+	unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
+	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
+
+	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
+		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
+		max_data -= tmp;
+	}
+	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
+	   so it might end up with fewer data blocks */
+	if (max_data <= *data_blocks)
+		return;
+	*data_blocks = max_data;
+	*ind_blocks = max_blocks - max_data;
+	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
+	if (*len > max) {
+		*len = max;
+		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
+	}
+}
+
+static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
+			   loff_t len)
+{
+	struct inode *inode = file->f_path.dentry->d_inode;
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct gfs2_inode *ip = GFS2_I(inode);
+	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
+	loff_t bytes, max_bytes;
+	struct gfs2_alloc *al;
+	int error;
+	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
+	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
+
+	/* We only support the FALLOC_FL_KEEP_SIZE mode */
+	if (mode & ~FALLOC_FL_KEEP_SIZE)
+		return -EOPNOTSUPP;
+
+	offset = (offset >> sdp->sd_sb.sb_bsize_shift) <<
+		 sdp->sd_sb.sb_bsize_shift;
+
+	len = next - offset;
+	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
+	if (!bytes)
+		bytes = UINT_MAX;
+
+	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
+	error = gfs2_glock_nq(&ip->i_gh);
+	if (unlikely(error))
+		goto out_uninit;
+
+	if (!gfs2_write_alloc_required(ip, offset, len))
+		goto out_unlock;
+
+	while (len > 0) {
+		if (len < bytes)
+			bytes = len;
+		al = gfs2_alloc_get(ip);
+		if (!al) {
+			error = -ENOMEM;
+			goto out_unlock;
+		}
+
+		error = gfs2_quota_lock_check(ip);
+		if (error)
+			goto out_alloc_put;
+
+retry:
+		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
+
+		al->al_requested = data_blocks + ind_blocks;
+		error = gfs2_inplace_reserve(ip);
+		if (error) {
+			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
+				bytes >>= 1;
+				goto retry;
+			}
+			goto out_qunlock;
+		}
+		max_bytes = bytes;
+		calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
+		al->al_requested = data_blocks + ind_blocks;
+
+		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
+			  RES_RG_HDR + gfs2_rg_blocks(al);
+		if (gfs2_is_jdata(ip))
+			rblocks += data_blocks ? data_blocks : 1;
+
+		error = gfs2_trans_begin(sdp, rblocks,
+					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
+		if (error)
+			goto out_trans_fail;
+
+		error = fallocate_chunk(inode, offset, max_bytes, mode);
+		gfs2_trans_end(sdp);
+
+		if (error)
+			goto out_trans_fail;
+
+		len -= max_bytes;
+		offset += max_bytes;
+		gfs2_inplace_release(ip);
+		gfs2_quota_unlock(ip);
+		gfs2_alloc_put(ip);
+	}
+	goto out_unlock;
+
+out_trans_fail:
+	gfs2_inplace_release(ip);
+out_qunlock:
+	gfs2_quota_unlock(ip);
+out_alloc_put:
+	gfs2_alloc_put(ip);
+out_unlock:
+	gfs2_glock_dq(&ip->i_gh);
+out_uninit:
+	gfs2_holder_uninit(&ip->i_gh);
+	return error;
+}
+
 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
 
 /**
@@ -765,6 +1021,7 @@ const struct file_operations gfs2_file_fops = {
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= generic_file_splice_write,
 	.setlease	= gfs2_setlease,
+	.fallocate	= gfs2_fallocate,
 };
 
 const struct file_operations gfs2_dir_fops = {
@@ -794,6 +1051,7 @@ const struct file_operations gfs2_file_fops_nolock = {
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= generic_file_splice_write,
 	.setlease	= generic_setlease,
+	.fallocate	= gfs2_fallocate,
 };
 
 const struct file_operations gfs2_dir_fops_nolock = {

fs/gfs2/ops_inode.c

@@ -18,8 +18,6 @@
 #include <linux/gfs2_ondisk.h>
 #include <linux/crc32.h>
 #include <linux/fiemap.h>
-#include <linux/swap.h>
-#include <linux/falloc.h>
 #include <asm/uaccess.h>
 
 #include "gfs2.h"
@@ -1257,261 +1255,6 @@ static int gfs2_removexattr(struct dentry *dentry, const char *name)
 	return ret;
 }
 
-static void empty_write_end(struct page *page, unsigned from,
-			   unsigned to)
-{
-	struct gfs2_inode *ip = GFS2_I(page->mapping->host);
-
-	page_zero_new_buffers(page, from, to);
-	flush_dcache_page(page);
-	mark_page_accessed(page);
-
-	if (!gfs2_is_writeback(ip))
-		gfs2_page_add_databufs(ip, page, from, to);
-
-	block_commit_write(page, from, to);
-}
-
-
-static int write_empty_blocks(struct page *page, unsigned from, unsigned to)
-{
-	unsigned start, end, next;
-	struct buffer_head *bh, *head;
-	int error;
-
-	if (!page_has_buffers(page)) {
-		error = __block_write_begin(page, from, to - from, gfs2_block_map);
-		if (unlikely(error))
-			return error;
-
-		empty_write_end(page, from, to);
-		return 0;
-	}
-
-	bh = head = page_buffers(page);
-	next = end = 0;
-	while (next < from) {
-		next += bh->b_size;
-		bh = bh->b_this_page;
-	}
-	start = next;
-	do {
-		next += bh->b_size;
-		if (buffer_mapped(bh)) {
-			if (end) {
-				error = __block_write_begin(page, start, end - start,
-							    gfs2_block_map);
-				if (unlikely(error))
-					return error;
-				empty_write_end(page, start, end);
-				end = 0;
-			}
-			start = next;
-		}
-		else
-			end = next;
-		bh = bh->b_this_page;
-	} while (next < to);
-
-	if (end) {
-		error = __block_write_begin(page, start, end - start, gfs2_block_map);
-		if (unlikely(error))
-			return error;
-		empty_write_end(page, start, end);
-	}
-
-	return 0;
-}
-
-static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
-			   int mode)
-{
-	struct gfs2_inode *ip = GFS2_I(inode);
-	struct buffer_head *dibh;
-	int error;
-	u64 start = offset >> PAGE_CACHE_SHIFT;
-	unsigned int start_offset = offset & ~PAGE_CACHE_MASK;
-	u64 end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
-	pgoff_t curr;
-	struct page *page;
-	unsigned int end_offset = (offset + len) & ~PAGE_CACHE_MASK;
-	unsigned int from, to;
-
-	if (!end_offset)
-		end_offset = PAGE_CACHE_SIZE;
-
-	error = gfs2_meta_inode_buffer(ip, &dibh);
-	if (unlikely(error))
-		goto out;
-
-	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-
-	if (gfs2_is_stuffed(ip)) {
-		error = gfs2_unstuff_dinode(ip, NULL);
-		if (unlikely(error))
-			goto out;
-	}
-
-	curr = start;
-	offset = start << PAGE_CACHE_SHIFT;
-	from = start_offset;
-	to = PAGE_CACHE_SIZE;
-	while (curr <= end) {
-		page = grab_cache_page_write_begin(inode->i_mapping, curr,
-						   AOP_FLAG_NOFS);
-		if (unlikely(!page)) {
-			error = -ENOMEM;
-			goto out;
-		}
-
-		if (curr == end)
-			to = end_offset;
-		error = write_empty_blocks(page, from, to);
-		if (!error && offset + to > inode->i_size &&
-		    !(mode & FALLOC_FL_KEEP_SIZE)) {
-			i_size_write(inode, offset + to);
-		}
-		unlock_page(page);
-		page_cache_release(page);
-		if (error)
-			goto out;
-		curr++;
-		offset += PAGE_CACHE_SIZE;
-		from = 0;
-	}
-
-	gfs2_dinode_out(ip, dibh->b_data);
-	mark_inode_dirty(inode);
-
-	brelse(dibh);
-
-out:
-	return error;
-}
-
-static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
-			    unsigned int *data_blocks, unsigned int *ind_blocks)
-{
-	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
-	unsigned int max_blocks = ip->i_alloc->al_rgd->rd_free_clone;
-	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);
-
-	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
-		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
-		max_data -= tmp;
-	}
-	/* This calculation isn't the exact reverse of gfs2_write_calc_reserve,
-	   so it might end up with fewer data blocks */
-	if (max_data <= *data_blocks)
-		return;
-	*data_blocks = max_data;
-	*ind_blocks = max_blocks - max_data;
-	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
-	if (*len > max) {
-		*len = max;
-		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
-	}
-}
-
-static long gfs2_fallocate(struct inode *inode, int mode, loff_t offset,
-			   loff_t len)
-{
-	struct gfs2_sbd *sdp = GFS2_SB(inode);
-	struct gfs2_inode *ip = GFS2_I(inode);
-	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
-	loff_t bytes, max_bytes;
-	struct gfs2_alloc *al;
-	int error;
-	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
-	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
-
-	/* We only support the FALLOC_FL_KEEP_SIZE mode */
-	if (mode & ~FALLOC_FL_KEEP_SIZE)
-		return -EOPNOTSUPP;
-
-	offset = (offset >> sdp->sd_sb.sb_bsize_shift) <<
-		 sdp->sd_sb.sb_bsize_shift;
-
-	len = next - offset;
-	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
-	if (!bytes)
-		bytes = UINT_MAX;
-
-	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
-	error = gfs2_glock_nq(&ip->i_gh);
-	if (unlikely(error))
-		goto out_uninit;
-
-	if (!gfs2_write_alloc_required(ip, offset, len))
-		goto out_unlock;
-
-	while (len > 0) {
-		if (len < bytes)
-			bytes = len;
-		al = gfs2_alloc_get(ip);
-		if (!al) {
-			error = -ENOMEM;
-			goto out_unlock;
-		}
-
-		error = gfs2_quota_lock_check(ip);
-		if (error)
-			goto out_alloc_put;
-
-retry:
-		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
-
-		al->al_requested = data_blocks + ind_blocks;
-		error = gfs2_inplace_reserve(ip);
-		if (error) {
-			if (error == -ENOSPC && bytes > sdp->sd_sb.sb_bsize) {
-				bytes >>= 1;
-				goto retry;
-			}
-			goto out_qunlock;
-		}
-		max_bytes = bytes;
-		calc_max_reserv(ip, len, &max_bytes, &data_blocks, &ind_blocks);
-		al->al_requested = data_blocks + ind_blocks;
-
-		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
-			  RES_RG_HDR + gfs2_rg_blocks(al);
-		if (gfs2_is_jdata(ip))
-			rblocks += data_blocks ? data_blocks : 1;
-
-		error = gfs2_trans_begin(sdp, rblocks,
-					 PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
-		if (error)
-			goto out_trans_fail;
-
-		error = fallocate_chunk(inode, offset, max_bytes, mode);
-		gfs2_trans_end(sdp);
-
-		if (error)
-			goto out_trans_fail;
-
-		len -= max_bytes;
-		offset += max_bytes;
-		gfs2_inplace_release(ip);
-		gfs2_quota_unlock(ip);
-		gfs2_alloc_put(ip);
-	}
-	goto out_unlock;
-
-out_trans_fail:
-	gfs2_inplace_release(ip);
-out_qunlock:
-	gfs2_quota_unlock(ip);
-out_alloc_put:
-	gfs2_alloc_put(ip);
-out_unlock:
-	gfs2_glock_dq(&ip->i_gh);
-out_uninit:
-	gfs2_holder_uninit(&ip->i_gh);
-	return error;
-}
-
-
 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		       u64 start, u64 len)
 {
@@ -1562,7 +1305,6 @@ const struct inode_operations gfs2_file_iops = {
 	.getxattr = gfs2_getxattr,
 	.listxattr = gfs2_listxattr,
 	.removexattr = gfs2_removexattr,
-	.fallocate = gfs2_fallocate,
 	.fiemap = gfs2_fiemap,
 };
 

fs/ocfs2/file.c

@@ -1989,9 +1989,10 @@ int ocfs2_change_file_space(struct file *file, unsigned int cmd,
 	return __ocfs2_change_file_space(file, inode, file->f_pos, cmd, sr, 0);
 }
 
-static long ocfs2_fallocate(struct inode *inode, int mode, loff_t offset,
+static long ocfs2_fallocate(struct file *file, int mode, loff_t offset,
 			    loff_t len)
 {
+	struct inode *inode = file->f_path.dentry->d_inode;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct ocfs2_space_resv sr;
 	int change_size = 1;
@@ -2002,9 +2003,6 @@ static long ocfs2_fallocate(struct inode *inode, int mode, loff_t offset,
 	if (!ocfs2_writes_unwritten_extents(osb))
 		return -EOPNOTSUPP;
 
-	if (S_ISDIR(inode->i_mode))
-		return -ENODEV;
-
 	if (mode & FALLOC_FL_KEEP_SIZE)
 		change_size = 0;
 
@@ -2612,7 +2610,6 @@ const struct inode_operations ocfs2_file_iops = {
 	.getxattr	= generic_getxattr,
 	.listxattr	= ocfs2_listxattr,
 	.removexattr	= generic_removexattr,
-	.fallocate	= ocfs2_fallocate,
 	.fiemap		= ocfs2_fiemap,
 };
 
@@ -2644,6 +2641,7 @@ const struct file_operations ocfs2_fops = {
 	.flock		= ocfs2_flock,
 	.splice_read	= ocfs2_file_splice_read,
 	.splice_write	= ocfs2_file_splice_write,
+	.fallocate	= ocfs2_fallocate,
 };
 
 const struct file_operations ocfs2_dops = {

fs/open.c

@@ -255,10 +255,10 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
 		return -EFBIG;
 
-	if (!inode->i_op->fallocate)
+	if (!file->f_op->fallocate)
 		return -EOPNOTSUPP;
 
-	return inode->i_op->fallocate(inode, mode, offset, len);
+	return file->f_op->fallocate(file, mode, offset, len);
 }
 
 SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len)

fs/xfs/linux-2.6/xfs_file.c

@@ -37,6 +37,7 @@
 #include "xfs_trace.h"
 
 #include <linux/dcache.h>
+#include <linux/falloc.h>
 
 static const struct vm_operations_struct xfs_file_vm_ops;
 
@@ -882,6 +883,60 @@ out_unlock:
 	return ret;
 }
 
+STATIC long
+xfs_file_fallocate(
+	struct file	*file,
+	int		mode,
+	loff_t		offset,
+	loff_t		len)
+{
+	struct inode	*inode = file->f_path.dentry->d_inode;
+	long		error;
+	loff_t		new_size = 0;
+	xfs_flock64_t	bf;
+	xfs_inode_t	*ip = XFS_I(inode);
+	int		cmd = XFS_IOC_RESVSP;
+
+	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+		return -EOPNOTSUPP;
+
+	bf.l_whence = 0;
+	bf.l_start = offset;
+	bf.l_len = len;
+
+	xfs_ilock(ip, XFS_IOLOCK_EXCL);
+
+	if (mode & FALLOC_FL_PUNCH_HOLE)
+		cmd = XFS_IOC_UNRESVSP;
+
+	/* check the new inode size is valid before allocating */
+	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
+	    offset + len > i_size_read(inode)) {
+		new_size = offset + len;
+		error = inode_newsize_ok(inode, new_size);
+		if (error)
+			goto out_unlock;
+	}
+
+	error = -xfs_change_file_space(ip, cmd, &bf, 0, XFS_ATTR_NOLOCK);
+	if (error)
+		goto out_unlock;
+
+	/* Change file size if needed */
+	if (new_size) {
+		struct iattr iattr;
+
+		iattr.ia_valid = ATTR_SIZE;
+		iattr.ia_size = new_size;
+		error = -xfs_setattr(ip, &iattr, XFS_ATTR_NOLOCK);
+	}
+
+out_unlock:
+	xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+	return error;
+}
+
+
 STATIC int
 xfs_file_open(
 	struct inode	*inode,
@@ -1000,6 +1055,7 @@ const struct file_operations xfs_file_operations = {
 	.open		= xfs_file_open,
 	.release	= xfs_file_release,
 	.fsync		= xfs_file_fsync,
+	.fallocate	= xfs_file_fallocate,
 };
 
 const struct file_operations xfs_dir_file_operations = {

fs/xfs/linux-2.6/xfs_iops.c

@@ -46,7 +46,6 @@
 #include <linux/namei.h>
 #include <linux/posix_acl.h>
 #include <linux/security.h>
-#include <linux/falloc.h>
 #include <linux/fiemap.h>
 #include <linux/slab.h>
 
@@ -505,64 +504,6 @@ xfs_vn_setattr(
 	return -xfs_setattr(XFS_I(dentry->d_inode), iattr, 0);
 }
 
-STATIC long
-xfs_vn_fallocate(
-	struct inode	*inode,
-	int		mode,
-	loff_t		offset,
-	loff_t		len)
-{
-	long		error;
-	loff_t		new_size = 0;
-	xfs_flock64_t	bf;
-	xfs_inode_t	*ip = XFS_I(inode);
-	int		cmd = XFS_IOC_RESVSP;
-
-	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
-		return -EOPNOTSUPP;
-
-	/* preallocation on directories not yet supported */
-	error = -ENODEV;
-	if (S_ISDIR(inode->i_mode))
-		goto out_error;
-
-	bf.l_whence = 0;
-	bf.l_start = offset;
-	bf.l_len = len;
-
-	xfs_ilock(ip, XFS_IOLOCK_EXCL);
-
-	if (mode & FALLOC_FL_PUNCH_HOLE)
-		cmd = XFS_IOC_UNRESVSP;
-
-	/* check the new inode size is valid before allocating */
-	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
-	    offset + len > i_size_read(inode)) {
-		new_size = offset + len;
-		error = inode_newsize_ok(inode, new_size);
-		if (error)
-			goto out_unlock;
-	}
-
-	error = -xfs_change_file_space(ip, cmd, &bf, 0, XFS_ATTR_NOLOCK);
-	if (error)
-		goto out_unlock;
-
-	/* Change file size if needed */
-	if (new_size) {
-		struct iattr iattr;
-
-		iattr.ia_valid = ATTR_SIZE;
-		iattr.ia_size = new_size;
-		error = -xfs_setattr(ip, &iattr, XFS_ATTR_NOLOCK);
-	}
-
-out_unlock:
-	xfs_iunlock(ip, XFS_IOLOCK_EXCL);
-out_error:
-	return error;
-}
-
 #define XFS_FIEMAP_FLAGS	(FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
 
 /*
@@ -656,7 +597,6 @@ static const struct inode_operations xfs_inode_operations = {
 	.getxattr		= generic_getxattr,
 	.removexattr		= generic_removexattr,
 	.listxattr		= xfs_vn_listxattr,
-	.fallocate		= xfs_vn_fallocate,
 	.fiemap			= xfs_vn_fiemap,
 };
 

include/linux/fs.h

@@ -1552,6 +1552,8 @@ struct file_operations {
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
 	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
 	int (*setlease)(struct file *, long, struct file_lock **);
+	long (*fallocate)(struct file *file, int mode, loff_t offset,
+			  loff_t len);
 };
 
 #define IPERM_FLAG_RCU	0x0001
@@ -1582,8 +1584,6 @@ struct inode_operations {
 	ssize_t (*listxattr) (struct dentry *, char *, size_t);
 	int (*removexattr) (struct dentry *, const char *);
 	void (*truncate_range)(struct inode *, loff_t, loff_t);
-	long (*fallocate)(struct inode *inode, int mode, loff_t offset,
-			  loff_t len);
 	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
 		      u64 len);
 } ____cacheline_aligned;