From 17f287172413dc04244781aa5302a0e4f10e2777 Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Thu, 23 May 2013 12:19:42 -0400 Subject: glusterfs: discard (hole punch) support Add support for the DISCARD file operation. Discard punches a hole in a file in the provided range. Block de-allocation is implemented via fallocate() (as requested via fuse and passed on to the brick fs) but a separate fop is created within gluster to emphasize the fact that discard changes file data (the discarded region is replaced with zeroes) and must invalidate caches where appropriate. BUG: 963678 Change-Id: I34633a0bfff2187afeab4292a15f3cc9adf261af Signed-off-by: Brian Foster Reviewed-on: http://review.gluster.org/5090 Tested-by: Gluster Build System Reviewed-by: Anand Avati --- api/examples/gfapi.py | 9 +++++++-- api/src/glfs-fops.c | 34 ++++++++++++++++++++++++++++++++++ api/src/glfs.h | 2 ++ 3 files changed, 43 insertions(+), 2 deletions(-) (limited to 'api') diff --git a/api/examples/gfapi.py b/api/examples/gfapi.py index 8dfe2791..8d9ed732 100755 --- a/api/examples/gfapi.py +++ b/api/examples/gfapi.py @@ -100,6 +100,8 @@ class File(object): def fallocate (self, mode, offset, len): return api.glfs_fallocate(self.fd, mode, offset, len) + def discard (self, offset, len): + return api.glfs_discard(self.fd, offset, len) class Dir(object): @@ -357,10 +359,13 @@ if __name__ == "__main__": fd = vol.creat(mypath,os.O_WRONLY|os.O_EXCL,0644) if not fd: return False, "creat error" - rc = fd.fallocate(0, 0, 1024) + rc = fd.fallocate(0, 0, 1024*1024) if rc != 0: return False, "fallocate error" - return True, "fallocate worked" + rc = fd.discard(4096, 4096) + if rc != 0: + return False, "discard error" + return True, "fallocate/discard worked" test_list = ( test_create_write, diff --git a/api/src/glfs-fops.c b/api/src/glfs-fops.c index 4bc0bb1b..fbc9f4b4 100644 --- a/api/src/glfs-fops.c +++ b/api/src/glfs-fops.c @@ -2665,6 +2665,40 @@ out: } +int +glfs_discard (struct glfs_fd *glfd, off_t offset, size_t len) +{ + int ret = -1; + xlator_t *subvol = NULL; + fd_t *fd = NULL; + + __glfs_entry_fd (glfd); + + subvol = glfs_active_subvol (glfd->fs); + if (!subvol) { + ret = -1; + errno = EIO; + goto out; + } + + fd = glfs_resolve_fd (glfd->fs, subvol, glfd); + if (!fd) { + ret = -1; + errno = EBADFD; + goto out; + } + + ret = syncop_discard (subvol, fd, offset, len); +out: + if (fd) + fd_unref(fd); + + glfs_subvol_done (glfd->fs, subvol); + + return ret; +} + + int glfs_chdir (struct glfs *fs, const char *path) { diff --git a/api/src/glfs.h b/api/src/glfs.h index 3888a103..700e10f1 100644 --- a/api/src/glfs.h +++ b/api/src/glfs.h @@ -450,6 +450,8 @@ int glfs_fremovexattr (glfs_fd_t *fd, const char *name); int glfs_fallocate(glfs_fd_t *fd, int keep_size, off_t offset, size_t len); +int glfs_discard(glfs_fd_t *fd, off_t offset, size_t len); + char *glfs_getcwd (glfs_t *fs, char *buf, size_t size); int glfs_chdir (glfs_t *fs, const char *path); -- cgit