path: root/security/commoncap.c
diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-17 11:01:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-17 11:01:31 -0700
commit7f427d3a6029331304f91ef4d7cf646f054216d2 (patch)
tree61c4a7b9b0ec387da0536324cc2c07b2427b9b46 /security/commoncap.c
parentede40902cf80714ece199977b308e2ee437cae0b (diff)
parent0e0162bb8c008fa7742f69d4d4982c8a37b88f95 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull parallel filesystem directory handling update from Al Viro. This is the main parallel directory work by Al that makes the vfs layer able to do lookup and readdir in parallel within a single directory. That's a big change, since this used to be all protected by the directory inode mutex. The inode mutex is replaced by an rwsem, and serialization of lookups of a single name is done by a "in-progress" dentry marker. The series begins with xattr cleanups, and then ends with switching filesystems over to actually doing the readdir in parallel (switching to the "iterate_shared()" that only takes the read lock). A more detailed explanation of the process from Al Viro: "The xattr work starts with some acl fixes, then switches ->getxattr to passing inode and dentry separately. This is the point where the things start to get tricky - that got merged into the very beginning of the -rc3-based #work.lookups, to allow untangling the security_d_instantiate() mess. The xattr work itself proceeds to switch a lot of filesystems to generic_...xattr(); no complications there. After that initial xattr work, the series then does the following: - untangle security_d_instantiate() - convert a bunch of open-coded lookup_one_len_unlocked() to calls of that thing; one such place (in overlayfs) actually yields a trivial conflict with overlayfs fixes later in the cycle - overlayfs ended up switching to a variant of lookup_one_len_unlocked() sans the permission checks. I would've dropped that commit (it gets overridden on merge from #ovl-fixes in #for-next; proper resolution is to use the variant in mainline fs/overlayfs/super.c), but I didn't want to rebase the damn thing - it was fairly late in the cycle... - some filesystems had managed to depend on lookup/lookup exclusion for *fs-internal* data structures in a way that would break if we relaxed the VFS exclusion. Fixing hadn't been hard, fortunately. - core of that series - parallel lookup machinery, replacing ->i_mutex with rwsem, making lookup_slow() take it only shared. At that point lookups happen in parallel; lookups on the same name wait for the in-progress one to be done with that dentry. Surprisingly little code, at that - almost all of it is in fs/dcache.c, with fs/namei.c changes limited to lookup_slow() - making it use the new primitive and actually switching to locking shared. - parallel readdir stuff - first of all, we provide the exclusion on per-struct file basis, same as we do for read() vs lseek() for regular files. That takes care of most of the needed exclusion in readdir/readdir; however, these guys are trickier than lookups, so I went for switching them one-by-one. To do that, a new method '->iterate_shared()' is added and filesystems are switched to it as they are either confirmed to be OK with shared lock on directory or fixed to be OK with that. I hope to kill the original method come next cycle (almost all in-tree filesystems are switched already), but it's still not quite finished. - several filesystems get switched to parallel readdir. The interesting part here is dealing with dcache preseeding by readdir; that needs minor adjustment to be safe with directory locked only shared. Most of the filesystems doing that got switched to in those commits. Important exception: NFS. Turns out that NFS folks, with their, er, insistence on VFS getting the fuck out of the way of the Smart Filesystem Code That Knows How And What To Lock(tm) have grown the locking of their own. They had their own homegrown rwsem, with lookup/readdir/atomic_open being *writers* (sillyunlink is the reader there). Of course, with VFS getting the fuck out of the way, as requested, the actual smarts of the smart filesystem code etc. had become exposed... - do_last/lookup_open/atomic_open cleanups. As the result, open() without O_CREAT locks the directory only shared. Including the ->atomic_open() case. Backmerge from #for-linus in the middle of that - atomic_open() fix got brought in. - then comes NFS switch to saner (VFS-based ;-) locking, killing the homegrown "lookup and readdir are writers" kinda-sorta rwsem. All exclusion for sillyunlink/lookup is done by the parallel lookups mechanism. Exclusion between sillyunlink and rmdir is a real rwsem now - rmdir being the writer. Result: NFS lookups/readdirs/O_CREAT-less opens happen in parallel now. - the rest of the series consists of switching a lot of filesystems to parallel readdir; in a lot of cases ->llseek() gets simplified as well. One backmerge in there (again, #for-linus - rockridge fix)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (74 commits) ext4: switch to ->iterate_shared() hfs: switch to ->iterate_shared() hfsplus: switch to ->iterate_shared() hostfs: switch to ->iterate_shared() hpfs: switch to ->iterate_shared() hpfs: handle allocation failures in hpfs_add_pos() gfs2: switch to ->iterate_shared() f2fs: switch to ->iterate_shared() afs: switch to ->iterate_shared() befs: switch to ->iterate_shared() befs: constify stuff a bit isofs: switch to ->iterate_shared() get_acorn_filename(): deobfuscate a bit btrfs: switch to ->iterate_shared() logfs: no need to lock directory in lseek switch ecryptfs to ->iterate_shared 9p: switch to ->iterate_shared() fat: switch to ->iterate_shared() romfs, squashfs: switch to ->iterate_shared() more trivial ->iterate_shared conversions ...
Diffstat (limited to 'security/commoncap.c')
1 files changed, 3 insertions, 3 deletions
diff --git a/security/commoncap.c b/security/commoncap.c
index 2074bf6a2fe3..e7fadde737f4 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -313,7 +313,7 @@ int cap_inode_need_killpriv(struct dentry *dentry)
if (!inode->i_op->getxattr)
return 0;
- error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
+ error = inode->i_op->getxattr(dentry, inode, XATTR_NAME_CAPS, NULL, 0);
if (error <= 0)
return 0;
return 1;
@@ -397,8 +397,8 @@ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data
if (!inode || !inode->i_op->getxattr)
return -ENODATA;
- size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
+ size = inode->i_op->getxattr((struct dentry *)dentry, inode,
if (size == -ENODATA || size == -EOPNOTSUPP)
/* no data, that's ok */
return -ENODATA;

Privacy Policy