diff options
| author | Daniel Xu <dxu@dxuuu.xyz> | 2020-03-12 21:03:15 +0100 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2020-03-16 20:53:47 +0100 |
| commit | a46a22955bae16fc5a756af7188d3ccb25c3f797 (patch) | |
| tree | c1a356cde80b186783225a8cb2d8f56f9474c1b3 | |
| parent | kernfs: kvmalloc xattr value instead of kmalloc (diff) | |
| download | linux-a46a22955bae16fc5a756af7188d3ccb25c3f797.tar.xz linux-a46a22955bae16fc5a756af7188d3ccb25c3f797.zip | |
kernfs: Add removed_size out param for simple_xattr_set
This helps set up size accounting in the next commit. Without this out
param, it's difficult to find out the removed xattr size without taking
a lock for longer and walking the xattr linked list twice.
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
| -rw-r--r-- | fs/kernfs/inode.c | 2 | ||||
| -rw-r--r-- | fs/xattr.c | 11 | ||||
| -rw-r--r-- | include/linux/xattr.h | 3 | ||||
| -rw-r--r-- | mm/shmem.c | 2 |
4 files changed, 14 insertions, 4 deletions
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index d0f7a5abd9a9..5f10ae95fbfa 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -303,7 +303,7 @@ int kernfs_xattr_set(struct kernfs_node *kn, const char *name, if (!attrs) return -ENOMEM; - return simple_xattr_set(&attrs->xattrs, name, value, size, flags); + return simple_xattr_set(&attrs->xattrs, name, value, size, flags, NULL); } static int kernfs_vfs_xattr_get(const struct xattr_handler *handler, diff --git a/fs/xattr.c b/fs/xattr.c index 0d3c9b4d1914..e13265e65871 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -860,6 +860,7 @@ int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, * @value: value of the xattr. If %NULL, will remove the attribute. * @size: size of the new xattr * @flags: %XATTR_{CREATE|REPLACE} + * @removed_size: returns size of the removed xattr, -1 if none removed * * %XATTR_CREATE is set, the xattr shouldn't exist already; otherwise fails * with -EEXIST. If %XATTR_REPLACE is set, the xattr should exist; @@ -868,7 +869,8 @@ int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, * Returns 0 on success, -errno on failure. */ int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, - const void *value, size_t size, int flags) + const void *value, size_t size, int flags, + ssize_t *removed_size) { struct simple_xattr *xattr; struct simple_xattr *new_xattr = NULL; @@ -895,8 +897,12 @@ int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, err = -EEXIST; } else if (new_xattr) { list_replace(&xattr->list, &new_xattr->list); + if (removed_size) + *removed_size = xattr->size; } else { list_del(&xattr->list); + if (removed_size) + *removed_size = xattr->size; } goto out; } @@ -908,6 +914,9 @@ int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, list_add(&new_xattr->list, &xattrs->head); xattr = NULL; } + + if (removed_size) + *removed_size = -1; out: spin_unlock(&xattrs->lock); if (xattr) { diff --git a/include/linux/xattr.h b/include/linux/xattr.h index 6dad031be3c2..4cf6e11f4a3c 100644 --- a/include/linux/xattr.h +++ b/include/linux/xattr.h @@ -102,7 +102,8 @@ struct simple_xattr *simple_xattr_alloc(const void *value, size_t size); int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, void *buffer, size_t size); int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, - const void *value, size_t size, int flags); + const void *value, size_t size, int flags, + ssize_t *removed_size); ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer, size_t size); void simple_xattr_list_add(struct simple_xattrs *xattrs, diff --git a/mm/shmem.c b/mm/shmem.c index c8f7540ef048..e6a7549faf20 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -3243,7 +3243,7 @@ static int shmem_xattr_handler_set(const struct xattr_handler *handler, struct shmem_inode_info *info = SHMEM_I(inode); name = xattr_full_name(handler, name); - return simple_xattr_set(&info->xattrs, name, value, size, flags); + return simple_xattr_set(&info->xattrs, name, value, size, flags, NULL); } static const struct xattr_handler shmem_security_xattr_handler = { |