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>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 651d523..4471a41 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -60,7 +60,6 @@
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 @@
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 @@
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: