Re: [PATCH v5 02/14] xfs: Replace attribute parameters with struct xfs_name

Brian Foster
2019-12-13T20:37:10Z

On Wed, Dec 11, 2019 at 09:15:01PM -0700, Allison Collins wrote:
> This patch replaces the attribute name and length parameters with a
> single struct xfs_name parameter. This helps to clean up the numbers of
> parameters being passed around and pre-simplifies the code some.
>
> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> ---
> fs/xfs/libxfs/xfs_attr.c | 22 +++++++++-------------
> fs/xfs/libxfs/xfs_attr.h | 12 +++++-------
> fs/xfs/libxfs/xfs_types.c | 10 ++++++++++
> fs/xfs/libxfs/xfs_types.h | 1 +
> fs/xfs/xfs_acl.c | 27 +++++++++++++--------------
> fs/xfs/xfs_ioctl.c | 23 +++++++++++++----------
> fs/xfs/xfs_iops.c | 6 +++---
> fs/xfs/xfs_xattr.c | 23 +++++++++++++----------
> 8 files changed, 67 insertions(+), 57 deletions(-)
>
...
> diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c
> index 4f59554..c81a904 100644
> --- a/fs/xfs/libxfs/xfs_types.c
> +++ b/fs/xfs/libxfs/xfs_types.c
> @@ -12,6 +12,16 @@
> #include "xfs_bit.h"
> #include "xfs_mount.h"
>
> +/* Initialize a struct xfs_name with a null terminated string name */
> +void
> +xfs_name_init(
> + struct xfs_name *xname,
> + const char *name)
> +{
> + xname->name = name;
> + xname->len = (strlen(name));

Are the extra braces necessary here? Also, perhaps we should initialize
->type to zero or something so it doesn't carry garbage data.

> +}
> +
> /* Find the size of the AG, in blocks. */
> xfs_agblock_t
> xfs_ag_block_count(
...
> diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
> index b58e18c..7b0e5b7 100644
> --- a/fs/xfs/xfs_acl.c
> +++ b/fs/xfs/xfs_acl.c
> @@ -123,7 +123,7 @@ xfs_get_acl(struct inode *inode, int type)
> struct xfs_inode *ip = XFS_I(inode);
> struct posix_acl *acl = NULL;
> struct xfs_acl *xfs_acl = NULL;
> - unsigned char *ea_name;
> + struct xfs_name name;
> int error;
> int len;
>
> @@ -131,10 +131,10 @@ xfs_get_acl(struct inode *inode, int type)
>
> switch (type) {
> case ACL_TYPE_ACCESS:
> - ea_name = SGI_ACL_FILE;
> + name.name = SGI_ACL_FILE;
> break;
> case ACL_TYPE_DEFAULT:
> - ea_name = SGI_ACL_DEFAULT;
> + name.name = SGI_ACL_DEFAULT;
> break;
> default:
> BUG();
> @@ -145,9 +145,9 @@ xfs_get_acl(struct inode *inode, int type)
> * go out to the disk.
> */
> len = XFS_ACL_MAX_SIZE(ip->i_mount);
> - error = xfs_attr_get(ip, ea_name, strlen(ea_name),
> - (unsigned char **)&xfs_acl, &len,
> - ATTR_ALLOC | ATTR_ROOT);
> + xfs_name_init(&name, name.name);

Could we call xfs_name_init() in the switch branches above to avoid this
partial init weirdness? Same question applies below, otherwise looks Ok
to me.

Brian

> + error = xfs_attr_get(ip, &name, (unsigned char **)&xfs_acl, &len,
> + ATTR_ALLOC | ATTR_ROOT);
> if (error) {
> /*
> * If the attribute doesn't exist make sure we have a negative
> @@ -167,17 +167,17 @@ int
> __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
> {
> struct xfs_inode *ip = XFS_I(inode);
> - unsigned char *ea_name;
> + struct xfs_name name;
> int error;
>
> switch (type) {
> case ACL_TYPE_ACCESS:
> - ea_name = SGI_ACL_FILE;
> + name.name = SGI_ACL_FILE;
> break;
> case ACL_TYPE_DEFAULT:
> if (!S_ISDIR(inode->i_mode))
> return acl ? -EACCES : 0;
> - ea_name = SGI_ACL_DEFAULT;
> + name.name = SGI_ACL_DEFAULT;
> break;
> default:
> return -EINVAL;
> @@ -197,17 +197,16 @@ __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
> len -= sizeof(struct xfs_acl_entry) *
> (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
>
> - error = xfs_attr_set(ip, ea_name, strlen(ea_name),
> - (unsigned char *)xfs_acl, len, ATTR_ROOT);
> + xfs_name_init(&name, name.name);
> + error = xfs_attr_set(ip, &name, (unsigned char *)xfs_acl, len,
> + ATTR_ROOT);
>
> kmem_free(xfs_acl);
> } else {
> /*
> * A NULL ACL argument means we want to remove the ACL.
> */
> - error = xfs_attr_remove(ip, ea_name,
> - strlen(ea_name),
> - ATTR_ROOT);
> + error = xfs_attr_remove(ip, &name, ATTR_ROOT);
>
> /*
> * If the attribute didn't exist to start with that's fine.
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index f5a9bf9..4fc8698 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -357,7 +357,9 @@ xfs_attrmulti_attr_get(
> {
> unsigned char *kbuf;
> int error = -EFAULT;
> - size_t namelen;
> + struct xfs_name xname;
> +
> + xfs_name_init(&xname, name);
>
> if (*len > XFS_XATTR_SIZE_MAX)
> return -EINVAL;
> @@ -365,9 +367,7 @@ xfs_attrmulti_attr_get(
> if (!kbuf)
> return -ENOMEM;
>
> - namelen = strlen(name);
> - error = xfs_attr_get(XFS_I(inode), name, namelen, &kbuf, (int *)len,
> - flags);
> + error = xfs_attr_get(XFS_I(inode), &xname, &kbuf, (int *)len, flags);
> if (error)
> goto out_kfree;
>
> @@ -389,7 +389,9 @@ xfs_attrmulti_attr_set(
> {
> unsigned char *kbuf;
> int error;
> - size_t namelen;
> + struct xfs_name xname;
> +
> + xfs_name_init(&xname, name);
>
> if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
> return -EPERM;
> @@ -400,8 +402,7 @@ xfs_attrmulti_attr_set(
> if (IS_ERR(kbuf))
> return PTR_ERR(kbuf);
>
> - namelen = strlen(name);
> - error = xfs_attr_set(XFS_I(inode), name, namelen, kbuf, len, flags);
> + error = xfs_attr_set(XFS_I(inode), &xname, kbuf, len, flags);
> if (!error)
> xfs_forget_acl(inode, name, flags);
> kfree(kbuf);
> @@ -415,12 +416,14 @@ xfs_attrmulti_attr_remove(
> uint32_t flags)
> {
> int error;
> - size_t namelen;
> + struct xfs_name xname;
> +
> + xfs_name_init(&xname, name);
>
> if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
> return -EPERM;
> - namelen = strlen(name);
> - error = xfs_attr_remove(XFS_I(inode), name, namelen, flags);
> +
> + error = xfs_attr_remove(XFS_I(inode), &xname, flags);
> if (!error)
> xfs_forget_acl(inode, name, flags);
> return error;
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 81f2f93..e85bbf5 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -48,11 +48,11 @@ xfs_initxattrs(
> const struct xattr *xattr;
> struct xfs_inode *ip = XFS_I(inode);
> int error = 0;
> + struct xfs_name name;
>
> for (xattr = xattr_array; xattr->name != NULL; xattr++) {
> - error = xfs_attr_set(ip, xattr->name,
> - strlen(xattr->name),
> - xattr->value, xattr->value_len,
> + xfs_name_init(&name, xattr->name);
> + error = xfs_attr_set(ip, &name, xattr->value, xattr->value_len,
> ATTR_SECURE);
> if (error < 0)
> break;
> diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
> index 1f1601f..5623682 100644
> --- a/fs/xfs/xfs_xattr.c
> +++ b/fs/xfs/xfs_xattr.c
> @@ -21,10 +21,12 @@ static int
> xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
> struct inode *inode, const char *name, void *value, size_t size)
> {
> - int xflags = handler->flags;
> - struct xfs_inode *ip = XFS_I(inode);
> - int error, asize = size;
> - size_t namelen = strlen(name);
> + int xflags = handler->flags;
> + struct xfs_inode *ip = XFS_I(inode);
> + int error, asize = size;
> + struct xfs_name xname;
> +
> + xfs_name_init(&xname, name);
>
> /* Convert Linux syscall to XFS internal ATTR flags */
> if (!size) {
> @@ -32,8 +34,8 @@ xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
> value = NULL;
> }
>
> - error = xfs_attr_get(ip, name, namelen, (unsigned char **)&value,
> - &asize, xflags);
> + error = xfs_attr_get(ip, &xname, (unsigned char **)&value, &asize,
> + xflags);
> if (error)
> return error;
> return asize;
> @@ -69,7 +71,9 @@ xfs_xattr_set(const struct xattr_handler *handler, struct dentry *unused,
> int xflags = handler->flags;
> struct xfs_inode *ip = XFS_I(inode);
> int error;
> - size_t namelen = strlen(name);
> + struct xfs_name xname;
> +
> + xfs_name_init(&xname, name);
>
> /* Convert Linux syscall to XFS internal ATTR flags */
> if (flags & XATTR_CREATE)
> @@ -78,9 +82,8 @@ xfs_xattr_set(const struct xattr_handler *handler, struct dentry *unused,
> xflags |= ATTR_REPLACE;
>
> if (!value)
> - return xfs_attr_remove(ip, name,
> - namelen, xflags);
> - error = xfs_attr_set(ip, name, namelen, (void *)value, size, xflags);
> + return xfs_attr_remove(ip, &xname, xflags);
> + error = xfs_attr_set(ip, &xname, (void *)value, size, xflags);
> if (!error)
> xfs_forget_acl(inode, name, xflags);
>
> --
> 2.7.4
>