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* ovl: generalize ovl_create_workdir()Amir Goldstein2017-07-041-16/+25
| | | | | | | | | | | | | | Pass in the subdir name to create and specify if subdir is persistent or if it should be cleaned up on every mount. Move fallback to readonly mount on failure to create dir and print of error message into the helper. This function is going to be used for creating the persistent 'index' dir under workbasedir. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: relax same fs constrain for ovl_check_origin()Amir Goldstein2017-07-041-18/+24
| | | | | | | | For the case of all layers not on the same fs, try to decode the copy up origin file handle on any of the lower layers. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: get exclusive ownership on upper/work dirsAmir Goldstein2017-07-042-3/+29
| | | | | | | | | | | | | | | Bad things can happen if several concurrent overlay mounts try to use the same upperdir/workdir path. Try to get the 'inuse' advisory lock on upperdir and workdir. Fail mount if another overlay mount instance or another user holds the 'inuse' lock on these directories. Note that this provides no protection for concurrent overlay mount that use overlapping (i.e. descendant) upper/work dirs. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* vfs: introduce inode 'inuse' lockAmir Goldstein2017-07-042-0/+33
| | | | | | | | | | | | | | Added an i_state flag I_INUSE and helpers to set/clear/test the bit. The 'inuse' lock is an 'advisory' inode lock, that can be used to extend exclusive create protection beyond parent->i_mutex lock among cooperating users. This is going to be used by overlayfs to get exclusive ownership on upper and work dirs among overlayfs mounts. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move cache and version to ovl_inodeMiklos Szeredi2017-07-043-17/+13
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: use ovl_inode mutex to synchronize concurrent copy upAmir Goldstein2017-07-043-20/+11
| | | | | | | | | | | | Use the new ovl_inode mutex to synchonize concurrent copy up instead of the super block copy up workqueue. Moving the synchronization object from the overlay dentry to the overlay inode is needed for synchonizing concurrent copy up of lower hardlinks to the same upper inode. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move impure to ovl_inodeMiklos Szeredi2017-07-046-17/+26
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move redirect to ovl_inodeMiklos Szeredi2017-07-044-9/+9
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: move __upperdentry to ovl_inodeMiklos Szeredi2017-07-048-94/+79
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: compare inodesMiklos Szeredi2017-07-041-4/+9
| | | | | | | When checking for consistency in directory operations (unlink, rename, etc.) match inodes not dentries. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: use i_private only as a keyMiklos Szeredi2017-07-045-20/+37
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: simplify getting inodeMiklos Szeredi2017-07-045-37/+36
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: allocate an ovl_inode structAmir Goldstein2017-07-042-2/+63
| | | | | | | | We need some more space to store overlay inode data in memory, so allocate overlay inodes from a slab of struct ovl_inode. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: fix nlink leak in ovl_rename()Amir Goldstein2017-07-041-0/+7
| | | | | | | | | | | This patch fixes an overlay inode nlink leak in the case where ovl_rename() renames over a non-dir. This is not so critical, because overlay inode doesn't rely on nlink dropping to zero for inode deletion. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid into ↵Miklos Szeredi2017-07-043-6/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | overlayfs-next UUID/GUID updates: - introduce the new uuid_t/guid_t types that are going to replace the somewhat confusing uuid_be/uuid_le types and make the terminology fit the various specs, as well as the userspace libuuid library. (me, based on a previous version from Amir) - consolidated generic uuid/guid helper functions lifted from XFS and libnvdimm (Amir and me) - conversions to the new types and helpers (Amir, Andy and me)
| * overlayfs: use uuid_t instead of uuid_beChristoph Hellwig2017-06-052-2/+2
| | | | | | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
| * fs: switch ->s_uuid to uuid_tChristoph Hellwig2017-06-052-4/+3
| | | | | | | | | | | | | | | | | | | | For some file systems we still memcpy into it, but in various places this already allows us to use the proper uuid helpers. More to come.. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* | ovl: don't set origin on broken lower hardlinkMiklos Szeredi2017-06-281-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When copying up a file that has multiple hard links we need to break any association with the origin file. This makes copy-up be essentially an atomic replace. The new file has nothing to do with the old one (except having the same data and metadata initially), so don't set the overlay.origin attribute. We can relax this in the future when we are able to index upper object by origin. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 3a1e819b4e80 ("ovl: store file handle of lower inode on copy up")
* | ovl: copy-up: don't unlock between lookup and linkMiklos Szeredi2017-06-281-12/+12
|/ | | | | | | | | | | Nothing prevents mischief on upper layer while we are busy copying up the data. Move the lookup right before the looked up dentry is actually used. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 01ad3eb8a073 ("ovl: concurrent copy up of regular files") Cc: <stable@vger.kernel.org> # v4.11
* ovl: filter trusted xattr for non-adminMiklos Szeredi2017-05-291-1/+11
| | | | | | | | | | Filesystems filter out extended attributes in the "trusted." domain for unprivlieged callers. Overlay calls underlying filesystem's method with elevated privs, so need to do the filtering in overlayfs too. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: mark upper merge dir with type origin entries "impure"Amir Goldstein2017-05-296-58/+60
| | | | | | | | | | | | | | | | | | | | An upper dir is marked "impure" to let ovl_iterate() know that this directory may contain non pure upper entries whose d_ino may need to be read from the origin inode. We already mark a non-merge dir "impure" when moving a non-pure child entry inside it, to let ovl_iterate() know not to iterate the non-merge dir directly. Mark also a merge dir "impure" when moving a non-pure child entry inside it and when copying up a child entry inside it. This can be used to optimize ovl_iterate() to perform a "pure merge" of upper and lower directories, merging the content of the directories, without having to read d_ino from origin inodes. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: mark upper dir with type origin entries "impure"Amir Goldstein2017-05-195-2/+79
| | | | | | | | | | | | | When moving a merge dir or non-dir with copy up origin into a non-merge upper dir (a.k.a pure upper dir), we are marking the target parent dir "impure". ovl_iterate() iterates pure upper dirs directly, because there is no need to filter out whiteouts and merge dir content with lower dir. But for the case of an "impure" upper dir, ovl_iterate() will not be able to iterate the real upper dir directly, because it will need to lookup the origin inode and use it to fill d_ino. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: remove unused arg from ovl_lookup_temp()Miklos Szeredi2017-05-193-6/+6
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: handle rename when upper doesn't support xattrAmir Goldstein2017-05-193-19/+20
| | | | | | | | | | | | | | On failure to set opaque/redirect xattr on rename, skip setting xattr and return -EXDEV. On failure to set opaque xattr when creating a new directory, -EIO is returned instead of -EOPNOTSUPP. Any failure to set those xattr will be recorded in super block and then setting any xattr on upper won't be attempted again. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: don't fail copy-up if upper doesn't support xattrMiklos Szeredi2017-05-181-1/+5
| | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: check on mount time if upper fs supports setting xattrAmir Goldstein2017-05-184-0/+38
| | | | | | | | | | | xattr are needed by overlayfs for setting opaque dir, redirect dir and copy up origin. Check at mount time by trying to set the overlay.opaque xattr on the workdir and if that fails issue a warning message. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: fix creds leak in copy up error pathAmir Goldstein2017-05-181-5/+6
| | | | | | | Fixes: 42f269b92540 ("ovl: rearrange code in ovl_copy_up_locked()") Cc: <stable@vger.kernel.org> # v4.11 Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* ovl: select EXPORTFSArnd Bergmann2017-05-151-0/+1
| | | | | | | | | | | | | | We get a link error when EXPORTFS is not enabled: ERROR: "exportfs_encode_fh" [fs/overlayfs/overlay.ko] undefined! ERROR: "exportfs_decode_fh" [fs/overlayfs/overlay.ko] undefined! This adds a Kconfig 'select' statement for overlayfs, the same way that it is done for the other users of exportfs. Fixes: 3a1e819b4e80 ("ovl: store file handle of lower inode on copy up") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge branch 'overlayfs-linus' of ↵Linus Torvalds2017-05-108-50/+415
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs update from Miklos Szeredi: "The biggest part of this is making st_dev/st_ino on the overlay behave like a normal filesystem (i.e. st_ino doesn't change on copy up, st_dev is the same for all files and directories). Currently this only works if all layers are on the same filesystem, but future work will move the general case towards more sane behavior. There are also miscellaneous fixes, including fixes to handling append-only files. There's a small change in the VFS, but that only has an effect on overlayfs, since otherwise file->f_path.dentry->inode and file_inode(file) are always the same" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: update documentation w.r.t. constant inode numbers ovl: persistent inode numbers for upper hardlinks ovl: merge getattr for dir and nondir ovl: constant st_ino/st_dev across copy up ovl: persistent inode number for directories ovl: set the ORIGIN type flag ovl: lookup non-dir copy-up-origin by file handle ovl: use an auxiliary var for overlay root entry ovl: store file handle of lower inode on copy up ovl: check if all layers are on the same fs ovl: do not set overlay.opaque on non-dir create ovl: check IS_APPEND() on real upper inode vfs: ftruncate check IS_APPEND() on real upper inode ovl: Use designated initializers ovl: lockdep annotate of nested stacked overlayfs inode lock
| * ovl: persistent inode numbers for upper hardlinksAmir Goldstein2017-05-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An upper type non directory dentry that is a copy up target should have a reference to its lower copy up origin. There are three ways for an upper type dentry to be instantiated: 1. A lower type dentry that is being copied up 2. An entry that is found in upper dir by ovl_lookup() 3. A negative dentry is hardlinked to an upper type dentry In the first case, the lower reference is set before copy up. In the second case, the lower reference is found by ovl_lookup(). In the last case of hardlinked upper dentry, it is not easy to update the lower reference of the negative dentry. Instead, drop the newly hardlinked negative dentry from dcache and let the next access call ovl_lookup() to find its lower reference. This makes sure that the inode number reported by stat(2) after the hardlink is created is the same inode number that will be reported by stat(2) after mount cycle, which is the inode number of the lower copy up origin of the hardlink source. NOTE that this does not fix breaking of lower hardlinks on copy up, but only fixes the case of lower nlink == 1, whose upper copy up inode is hardlinked in upper dir. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: merge getattr for dir and nondirMiklos Szeredi2017-05-053-64/+30
| | | | | | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: constant st_ino/st_dev across copy upAmir Goldstein2017-05-051-1/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When all layers are on the same underlying filesystem, let stat(2) return st_dev/st_ino values of the copy up origin inode if it is known. This results in constant st_ino/st_dev representation of files in an overlay mount before and after copy up. When the underlying filesystem support NFS exportfs, the result is also persistent st_ino/st_dev representation before and after mount cycle. Lower hardlinks are broken on copy up to different upper files, so we cannot use the lower origin st_ino for those different files, even for the same fs case. When all overlay layers are on the same fs, use overlay st_dev for non-dirs to get the correct result from du -x. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: persistent inode number for directoriesAmir Goldstein2017-05-051-4/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | stat(2) on overlay directories reports the overlay temp inode number, which is constant across copy up, but is not persistent. When all layers are on the same fs, report the copy up origin inode number for directories. This inode number is persistent, unique across the overlay mount and constant across copy up. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: set the ORIGIN type flagAmir Goldstein2017-05-052-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | For directory entries, non zero oe->numlower implies OVL_TYPE_MERGE. Define a new type flag OVL_TYPE_ORIGIN to indicate that an entry holds a reference to its lower copy up origin. For directory entries ORIGIN := MERGE && UPPER. For non-dir entries ORIGIN means that a lower type dentry has been recently copied up or that we were able to find the copy up origin from overlay.origin xattr. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: lookup non-dir copy-up-origin by file handleAmir Goldstein2017-05-051-0/+132
| | | | | | | | | | | | | | | | | | | | | | | | If overlay.origin xattr is found on a non-dir upper inode try to get lower dentry by calling exportfs_decode_fh(). On failure to lookup by file handle to lower layer, do not lookup the copy up origin by name, because the lower found by name could be another file in case the upper file was renamed. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: use an auxiliary var for overlay root entryAmir Goldstein2017-05-051-5/+4
| | | | | | | | | | Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: store file handle of lower inode on copy upAmir Goldstein2017-05-052-0/+118
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes it is interesting to know if an upper file is pure upper or a copy up target, and if it is a copy up target, it may be interesting to find the copy up origin. This will be used to preserve lower inode numbers across copy up. Store the lower inode file handle in upper inode extended attribute overlay.origin on copy up to use it later for these cases. Store the lower filesystem uuid along side the file handle, so we can validate that we are looking for the origin file in the original fs. If lower fs does not support NFS export ops store a zero sized xattr so we can always use the overlay.origin xattr to distinguish between a copy up and a pure upper inode. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: check if all layers are on the same fsAmir Goldstein2017-05-054-0/+18
| | | | | | | | | | | | | | | | | | | | | | Some features can only work when all layers are on the same fs. Test this condition during mount time, so features can check them later. Add helper ovl_same_sb() to return the common super block in case all layers are on the same fs. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: do not set overlay.opaque on non-dir createAmir Goldstein2017-04-261-1/+1
| | | | | | | | | | | | | | | | | | | | The optimization for opaque dir create was wrongly being applied also to non-dir create. Fixes: 97c684cc9110 ("ovl: create directories inside merged parent opaque") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.10
| * ovl: check IS_APPEND() on real upper inodeAmir Goldstein2017-04-201-3/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | For overlay file open, check IS_APPEND() on the real upper inode inside d_real(), because the overlay inode does not have the S_APPEND flag and IS_APPEND() can only be checked at open time. Note that because overlayfs does not copy up the chattr inode flags (i.e. S_APPEND, S_IMMUTABLE), the IS_APPEND() check is only relevant for upper inodes that were set with chattr +a and not to lower inodes that had chattr +a before copy up. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: Use designated initializersKees Cook2017-04-202-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Prepare to mark sensitive kernel structures for randomization by making sure they're using designated initializers. These were identified during allyesconfig builds of x86, arm, and arm64, with most initializer fixes extracted from grsecurity. For these cases, use { }, which will be zero-filled, instead of undesignated NULLs. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: lockdep annotate of nested stacked overlayfs inode lockAmir Goldstein2017-03-081-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An overlayfs instance can be the lower layer of another overlayfs instance. This setup triggers a lockdep splat of possible recursive locking of sb->s_type->i_mutex_key in iterate_dir(). Trimmed snip: [ INFO: possible recursive locking detected ] bash/2468 is trying to acquire lock: &sb->s_type->i_mutex_key#14, at: iterate_dir+0x7d/0x15c but task is already holding lock: &sb->s_type->i_mutex_key#14, at: iterate_dir+0x7d/0x15c One problem observed with this splat is that ovl_new_inode() does not call lockdep_annotate_inode_mutex_key() to annotate the dir inode lock as &sb->s_type->i_mutex_dir_key like other fs do. The other problem is that the 2 nested levels of overlayfs inode lock are annotated using the same key, which is the cause of the false positive lockdep warning. Fix this by annotating overlayfs inode lock in ovl_fill_inode() according to stack level of the super block instance and use different key for dir vs. non-dir like other fs do. Here is an edited snip from /proc/lockdep_chains after iterate_dir() of nested overlayfs: [...] &ovl_i_mutex_dir_key[depth] (stack_depth=2) [...] &ovl_i_mutex_dir_key[depth]#2 (stack_depth=1) [...] &type->i_mutex_dir_key (stack_depth=0) Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | overlayfs: remove now unnecessary header file includeLinus Torvalds2017-03-081-1/+0
|/ | | | | | | | | | | | This removes the extra include header file that was added in commit e58bc927835a "Pull overlayfs updates from Miklos Szeredi" now that it is no longer needed. There are probably other such includes that got added during the scheduler header splitup series, but this is the one that annoyed me personally and I know about. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'overlayfs-linus' of ↵Linus Torvalds2017-03-035-27/+148
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "Because copy up can take a long time, serialized copy ups could be a big performance bottleneck. This update allows concurrent copy up of regular files eliminating this potential problem. There are also minor fixes" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: drop CAP_SYS_RESOURCE from saved mounter's credentials ovl: properly implement sync_filesystem() ovl: concurrent copy up of regular files ovl: introduce copy up waitqueue ovl: copy up regular file using O_TMPFILE ovl: rearrange code in ovl_copy_up_locked() ovl: check if upperdir fs supports O_TMPFILE
| * ovl: drop CAP_SYS_RESOURCE from saved mounter's credentialsKonstantin Khlebnikov2017-02-071-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If overlay was mounted by root then quota set for upper layer does not work because overlay now always use mounter's credentials for operations. Also overlay might deplete reserved space and inodes in ext4. This patch drops capability SYS_RESOURCE from saved credentials. This affects creation new files, whiteouts, and copy-up operations. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Fixes: 1175b6b8d963 ("ovl: do operations on underlying file system in mounter's context") Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: properly implement sync_filesystem()Amir Goldstein2017-02-071-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | overlayfs syncs all inode pages on sync_filesystem(), but it also needs to call s_op->sync_fs() of upper fs for metadata sync. This fixes correctness of syncfs(2) as demonstrated by following xfs specific test: xfs_sync_stats() { echo $1 echo -n "xfs_log_force = " grep log /proc/fs/xfs/stat | awk '{ print $5 }' } xfs_sync_stats "before touch" touch x xfs_sync_stats "after touch" xfs_io -c syncfs . xfs_sync_stats "after syncfs" xfs_io -c fsync x xfs_sync_stats "after fsync" xfs_io -c fsync x xfs_sync_stats "after fsync #2" When this test is run in overlay mount over xfs, log force count does not increase with syncfs command. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: concurrent copy up of regular filesAmir Goldstein2017-02-071-4/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that copy up of regular file is done using O_TMPFILE, we don't need to hold rename_lock throughout copy up. Use the copy up waitqueue to synchronize concurrent copy up of the same file. Different regular files can be copied up concurrently. The upper dir inode_lock is taken instead of rename_lock, because it is needed for lookup and later for linking the temp file, but it is released while copying up data. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: introduce copy up waitqueueAmir Goldstein2017-02-074-0/+35
| | | | | | | | | | | | | | | | | | | | The overlay sb 'copyup_wq' and overlay inode 'copying' condition variable are about to replace the upper sb rename_lock, as finer grained synchronization objects for concurrent copy up. Suggested-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: copy up regular file using O_TMPFILEAmir Goldstein2017-02-071-7/+20
| | | | | | | | | | | | | | | | | | | | In preparation for concurrent copy up, implement copy up of regular file as O_TMPFILE that is linked to upperdir instead of a file in workdir that is moved to upperdir. Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: rearrange code in ovl_copy_up_locked()Amir Goldstein2017-02-071-24/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | As preparation to implementing copy up with O_TMPFILE, name the variable for dentry before final rename 'temp' and assign it to 'newdentry' only after rename. Also lookup upper dentry before looking up temp dentry and move ovl_set_timestamps() into ovl_copy_up_locked(), because that is going to be more convenient for upcoming change. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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