Commit a46a2295 authored by Daniel Xu's avatar Daniel Xu Committed by Tejun Heo
Browse files

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: default avatarDaniel Xu <dxu@dxuuu.xyz>
Acked-by: default avatarChris Down <chris@chrisdown.name>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent fdc85222

fs/kernfs/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -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,

fs/xattr.c

+10 −1
Original line number Diff line number Diff line
@@ -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) {

include/linux/xattr.h

+2 −1
Original line number Diff line number Diff line
@@ -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,

mm/shmem.c

+1 −1
Original line number Diff line number Diff line
@@ -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 = {

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