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| author | Darrick J. Wong <darrick.wong@oracle.com> | 2016-10-03 18:11:14 +0200 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2016-10-03 18:11:14 +0200 |
| commit | 71be6b4942dd64bc17728f82f787be98fd8afed7 (patch) | |
| tree | c5a219e8c9d574051b01551d6e24012519213a03 /fs/open.c | |
| parent | vfs: support FS_XFLAG_COWEXTSIZE and get/set of CoW extent size hint (diff) | |
| download | linux-71be6b4942dd64bc17728f82f787be98fd8afed7.tar.xz linux-71be6b4942dd64bc17728f82f787be98fd8afed7.zip | |
vfs: add a FALLOC_FL_UNSHARE mode to fallocate to unshare a range of blocks
Add a new fallocate mode flag that explicitly unshares blocks on
filesystems that support such features. The new flag can only
be used with an allocate-mode fallocate call.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Diffstat (limited to 'fs/open.c')
| -rw-r--r-- | fs/open.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/open.c b/fs/open.c index 4fd6e256f4f4..d58525dda28d 100644 --- a/fs/open.c +++ b/fs/open.c @@ -256,6 +256,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) (mode & ~FALLOC_FL_INSERT_RANGE)) return -EINVAL; + /* Unshare range should only be used with allocate mode. */ + if ((mode & FALLOC_FL_UNSHARE_RANGE) && + (mode & ~(FALLOC_FL_UNSHARE_RANGE | FALLOC_FL_KEEP_SIZE))) + return -EINVAL; + if (!(file->f_mode & FMODE_WRITE)) return -EBADF; |