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

[Allison Collins <allison.henderson@xxxxxxxxxx>]

On 12/13/19 6:07 AM, Brian Foster wrote:
> 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@xxxxxxxxxx>
> > ---
> >   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.
I may have borrowed the extra braces from somewhere else in the code. 
Will clean out and also add the type init.

> > +}
> > +
> >   /* 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
Sure, I will scoot that up.  Thx!
Allison

> > +	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