diff mbox series

[v4,05/17] xfs: Add xfs_has_attr and subroutines

Message ID 20191107012801.22863-6-allison.henderson@oracle.com (mailing list archive)
State Superseded
Headers show
Series xfs: Delay Ready Attributes | expand

Commit Message

Allison Henderson Nov. 7, 2019, 1:27 a.m. UTC
From: Allison Henderson <allison.henderson@oracle.com>

This patch adds a new functions to check for the existence of
an attribute.  Subroutines are also added to handle the cases
of leaf blocks, nodes or shortform.  Common code that appears
in existing attr add and remove functions have been factored
out to help reduce the appearence of duplicated code.  We will
need these routines later for delayed attributes since delayed
operations cannot return error codes.

Signed-off-by: Allison Collins <allison.henderson@oracle.com>
---
 fs/xfs/libxfs/xfs_attr.c      | 154 +++++++++++++++++++++++++++---------------
 fs/xfs/libxfs/xfs_attr.h      |   1 +
 fs/xfs/libxfs/xfs_attr_leaf.c | 107 ++++++++++++++++++-----------
 fs/xfs/libxfs/xfs_attr_leaf.h |   2 +
 4 files changed, 171 insertions(+), 93 deletions(-)

Comments

Darrick J. Wong Nov. 8, 2019, 7:32 p.m. UTC | #1
On Wed, Nov 06, 2019 at 06:27:49PM -0700, Allison Collins wrote:
> From: Allison Henderson <allison.henderson@oracle.com>
> 
> This patch adds a new functions to check for the existence of
> an attribute.  Subroutines are also added to handle the cases
> of leaf blocks, nodes or shortform.  Common code that appears
> in existing attr add and remove functions have been factored
> out to help reduce the appearence of duplicated code.  We will
> need these routines later for delayed attributes since delayed
> operations cannot return error codes.
> 
> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> ---
>  fs/xfs/libxfs/xfs_attr.c      | 154 +++++++++++++++++++++++++++---------------
>  fs/xfs/libxfs/xfs_attr.h      |   1 +
>  fs/xfs/libxfs/xfs_attr_leaf.c | 107 ++++++++++++++++++-----------
>  fs/xfs/libxfs/xfs_attr_leaf.h |   2 +
>  4 files changed, 171 insertions(+), 93 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index 5cb83a8..c8a3273 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -46,6 +46,7 @@ STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
>  STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
>  STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
>  STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
> +STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
>  
>  /*
>   * Internal routines when attribute list is more than one block.
> @@ -53,6 +54,8 @@ STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
>  STATIC int xfs_attr_node_get(xfs_da_args_t *args);
>  STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
>  STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
> +STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
> +				 struct xfs_da_state **state);
>  STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
>  STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
>  
> @@ -310,6 +313,34 @@ xfs_attr_set_args(
>  }
>  
>  /*
> + * Return EEXIST if attr is found, or ENOATTR if not
> + */
> +int
> +xfs_has_attr(
> +	struct xfs_da_args      *args)

I was really hoping for a "replace ENOATTR/EEXIST with a boolean"
cleanup at the end of this series, though as a straight hoisting and
refactoring, this patch is ok for leaving the existing error code
overloading. :)

> +{
> +	struct xfs_inode        *dp = args->dp;
> +	struct xfs_buf		*bp;
> +	int                     error;
> +
> +	if (!xfs_inode_hasattr(dp)) {
> +		error = -ENOATTR;
> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
> +		error = xfs_attr_leaf_hasname(args, &bp);
> +		if (error != -ENOATTR && error != -EEXIST)
> +			goto out;
> +		xfs_trans_brelse(args->trans, bp);
> +	} else {
> +		error = xfs_attr_node_hasname(args, NULL);
> +	}
> +out:
> +	return error;
> +}
> +
> +/*
>   * Remove the attribute specified in @args.
>   */
>  int
> @@ -580,27 +611,20 @@ STATIC int
>  xfs_attr_leaf_addname(
>  	struct xfs_da_args	*args)
>  {
> -	struct xfs_inode	*dp;
>  	struct xfs_buf		*bp;
>  	int			retval, error, forkoff;
> +	struct xfs_inode	*dp = args->dp;
>  
>  	trace_xfs_attr_leaf_addname(args);
>  
>  	/*
> -	 * Read the (only) block in the attribute list in.
> -	 */
> -	dp = args->dp;
> -	args->blkno = 0;
> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
> -	if (error)
> -		return error;
> -
> -	/*
>  	 * Look up the given attribute in the leaf block.  Figure out if
>  	 * the given flags produce an error or call for an atomic rename.
>  	 */
> -	retval = xfs_attr3_leaf_lookup_int(bp, args);
> +	retval = xfs_attr_leaf_hasname(args, &bp);
> +	if (retval != -ENOATTR && retval != -EEXIST)
> +		return retval;
> +
>  	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
>  		xfs_trans_brelse(args->trans, bp);
>  		return retval;
> @@ -752,6 +776,24 @@ xfs_attr_leaf_addname(
>  }
>  
>  /*
> + * Return EEXIST if attr is found, or ENOATTR if not
> + */
> +STATIC int
> +xfs_attr_leaf_hasname(
> +	struct xfs_da_args      *args,
> +	struct xfs_buf		**bp)
> +{
> +	int                     error = 0;
> +
> +	error = xfs_attr3_leaf_read(args->trans, args->dp, 0,
> +				    XFS_DABUF_MAP_NOMAPPING, bp);
> +	if (error)
> +		return error;
> +
> +	return xfs_attr3_leaf_lookup_int(*bp, args);
> +}
> +
> +/*
>   * Remove a name from the leaf attribute list structure
>   *
>   * This leaf block cannot have a "remote" value, we only call this routine
> @@ -771,13 +813,11 @@ xfs_attr_leaf_removename(
>  	 * Remove the attribute.
>  	 */
>  	dp = args->dp;
> -	args->blkno = 0;
> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
> -	if (error)
> +
> +	error = xfs_attr_leaf_hasname(args, &bp);
> +	if (error != -ENOATTR && error != -EEXIST)
>  		return error;
>  
> -	error = xfs_attr3_leaf_lookup_int(bp, args);
>  	if (error == -ENOATTR) {
>  		xfs_trans_brelse(args->trans, bp);
>  		return error;
> @@ -816,13 +856,10 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>  
>  	trace_xfs_attr_leaf_get(args);
>  
> -	args->blkno = 0;
> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
> -	if (error)
> +	error = xfs_attr_leaf_hasname(args, &bp);
> +	if (error != -ENOATTR && error != -EEXIST)
>  		return error;
>  
> -	error = xfs_attr3_leaf_lookup_int(bp, args);
>  	if (error != -EEXIST)  {
>  		xfs_trans_brelse(args->trans, bp);
>  		return error;
> @@ -832,6 +869,38 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>  	return error;
>  }
>  
> +/*
> + * Return EEXIST if attr is found, or ENOATTR if not
> + * statep: If not null is set to point at the found state.  Caller will
> + * 	   be responsible for freeing the state in this case.
> + */
> +STATIC int
> +xfs_attr_node_hasname(
> +	struct xfs_da_args	*args,
> +	struct xfs_da_state	**statep)
> +{
> +	struct xfs_da_state	*state;
> +	int			retval, error;
> +
> +	state = xfs_da_state_alloc();
> +	state->args = args;
> +	state->mp = args->dp->i_mount;
> +
> +	/*
> +	 * Search to see if name exists, and get back a pointer to it.
> +	 */
> +	error = xfs_da3_node_lookup_int(state, &retval);
> +	if (error == 0)
> +		error = retval;
> +
> +	if (statep != NULL)
> +		*statep = state;
> +	else
> +		xfs_da_state_free(state);
> +
> +	return error;
> +}
> +
>  /*========================================================================
>   * External routines when attribute list size > geo->blksize
>   *========================================================================*/
> @@ -864,20 +933,17 @@ xfs_attr_node_addname(
>  	dp = args->dp;
>  	mp = dp->i_mount;
>  restart:
> -	state = xfs_da_state_alloc();
> -	state->args = args;
> -	state->mp = mp;
> -
>  	/*
>  	 * Search to see if name already exists, and get back a pointer
>  	 * to where it should go.
>  	 */
> -	error = xfs_da3_node_lookup_int(state, &retval);
> -	if (error)
> +	retval = xfs_attr_node_hasname(args, &state);
> +	if (retval != -ENOATTR)
>  		goto out;
> +
>  	blk = &state->path.blk[ state->path.active-1 ];
>  	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
> -	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
> +	if (args->name.type & ATTR_REPLACE) {
>  		goto out;
>  	} else if (retval == -EEXIST) {
>  		if (args->name.type & ATTR_CREATE)
> @@ -1079,29 +1145,15 @@ xfs_attr_node_removename(
>  {
>  	struct xfs_da_state	*state;
>  	struct xfs_da_state_blk	*blk;
> -	struct xfs_inode	*dp;
>  	struct xfs_buf		*bp;
>  	int			retval, error, forkoff;
> +	struct xfs_inode	*dp = args->dp;
>  
>  	trace_xfs_attr_node_removename(args);
>  
> -	/*
> -	 * Tie a string around our finger to remind us where we are.
> -	 */
> -	dp = args->dp;
> -	state = xfs_da_state_alloc();
> -	state->args = args;
> -	state->mp = dp->i_mount;
> -
> -	/*
> -	 * Search to see if name exists, and get back a pointer to it.
> -	 */
> -	error = xfs_da3_node_lookup_int(state, &retval);
> -	if (error || (retval != -EEXIST)) {
> -		if (error == 0)
> -			error = retval;
> +	error = xfs_attr_node_hasname(args, &state);
> +	if (error != -EEXIST)
>  		goto out;
> -	}
>  
>  	/*
>  	 * If there is an out-of-line value, de-allocate the blocks.
> @@ -1324,20 +1376,14 @@ xfs_attr_node_get(xfs_da_args_t *args)
>  
>  	trace_xfs_attr_node_get(args);
>  
> -	state = xfs_da_state_alloc();
> -	state->args = args;
> -	state->mp = args->dp->i_mount;
> -
>  	/*
>  	 * Search to see if name exists, and get back a pointer to it.
>  	 */
> -	error = xfs_da3_node_lookup_int(state, &retval);
> -	if (error) {
> +	error = xfs_attr_node_hasname(args, &state);
> +	if (error != -EEXIST) {
>  		retval = error;
>  		goto out_release;
>  	}
> -	if (retval != -EEXIST)
> -		goto out_release;
>  
>  	/*
>  	 * Get the value, local or "remote"
> diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
> index 44dd07a..3b5dad4 100644
> --- a/fs/xfs/libxfs/xfs_attr.h
> +++ b/fs/xfs/libxfs/xfs_attr.h
> @@ -150,6 +150,7 @@ int xfs_attr_set(struct xfs_inode *dp, struct xfs_name *name,
>  		 unsigned char *value, int valuelen, int flags);
>  int xfs_attr_set_args(struct xfs_da_args *args);
>  int xfs_attr_remove(struct xfs_inode *dp, struct xfs_name *name, int flags);
> +int xfs_has_attr(struct xfs_da_args *args);
>  int xfs_attr_remove_args(struct xfs_da_args *args);
>  int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
>  		  int flags, struct attrlist_cursor_kern *cursor);
> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
> index 93c3496..d06cfd6 100644
> --- a/fs/xfs/libxfs/xfs_attr_leaf.c
> +++ b/fs/xfs/libxfs/xfs_attr_leaf.c
> @@ -655,18 +655,67 @@ xfs_attr_shortform_create(xfs_da_args_t *args)
>  }
>  
>  /*
> + * Return -EEXIST if attr is found, or -ENOATTR if not
> + * args:  args containing attribute name and namelen
> + * sfep:  If not null, pointer will be set to the last attr entry found on
> +	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
> + * basep: If not null, pointer is set to the byte offset of the entry in the
> + *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
> + *	  the last entry in the list
> + */
> +int
> +xfs_attr_shortform_hasname(
> +	struct xfs_da_args	 *args,
> +	struct xfs_attr_sf_entry **sfep,
> +	int			 *basep)

Byte offsets can't be negative, so this should be unsigned int.

Seeing as we also return the location of the sf entry and byte offset,
maybe this ought to be called xfs_attr_sf_findname ?

> +{
> +	struct xfs_attr_shortform *sf;
> +	struct xfs_attr_sf_entry *sfe;
> +	int			base = sizeof(struct xfs_attr_sf_hdr);
> +	int			size = 0;
> +	int			end;
> +	int			i;
> +
> +	base = sizeof(struct xfs_attr_sf_hdr);
> +	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
> +	sfe = &sf->list[0];
> +	end = sf->hdr.count;
> +	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
> +			base += size, i++) {
> +		size = XFS_ATTR_SF_ENTSIZE(sfe);
> +		if (sfe->namelen != args->name.len)
> +			continue;
> +		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
> +			continue;
> +		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> +			continue;
> +		break;
> +	}
> +
> +	if (sfep != NULL)
> +		*sfep = sfe;
> +
> +	if (basep != NULL)
> +		*basep = base;
> +
> +	if (i == end)
> +		return -ENOATTR;
> +	return -EEXIST;
> +}
> +
> +/*
>   * Add a name/value pair to the shortform attribute list.
>   * Overflow from the inode has already been checked for.
>   */
>  void
>  xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>  {
> -	xfs_attr_shortform_t *sf;
> -	xfs_attr_sf_entry_t *sfe;
> -	int i, offset, size;
> -	xfs_mount_t *mp;
> -	xfs_inode_t *dp;
> -	struct xfs_ifork *ifp;
> +	struct xfs_attr_shortform	*sf;
> +	struct xfs_attr_sf_entry	*sfe;
> +	int				offset, size, error;
> +	struct xfs_mount		*mp;
> +	struct xfs_inode		*dp;
> +	struct xfs_ifork		*ifp;
>  
>  	trace_xfs_attr_sf_add(args);
>  
> @@ -677,18 +726,8 @@ xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>  	ifp = dp->i_afp;
>  	ASSERT(ifp->if_flags & XFS_IFINLINE);
>  	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
> -	sfe = &sf->list[0];
> -	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
> -#ifdef DEBUG
> -		if (sfe->namelen != args->name.len)
> -			continue;
> -		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
> -			continue;
> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> -			continue;
> -		ASSERT(0);
> -#endif
> -	}
> +	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
> +	ASSERT(error != -EEXIST);

If this assertion triggers, the fs is corrupt and we need to log
something and bail out.  5.5 for-next will soon have a new
XFS_IS_CORRUPT macro that takes care of this, so you can do:

	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
	if (XFS_IS_CORRUPT(mp, error != -EEXIST))
		return -EFSCORRUPTED;

--D


>  
>  	offset = (char *)sfe - (char *)sf;
>  	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
> @@ -733,33 +772,23 @@ xfs_attr_fork_remove(
>  int
>  xfs_attr_shortform_remove(xfs_da_args_t *args)
>  {
> -	xfs_attr_shortform_t *sf;
> -	xfs_attr_sf_entry_t *sfe;
> -	int base, size=0, end, totsize, i;
> -	xfs_mount_t *mp;
> -	xfs_inode_t *dp;
> +	struct xfs_attr_shortform	*sf;
> +	struct xfs_attr_sf_entry	*sfe;
> +	int				base, size = 0, end, totsize;
> +	struct xfs_mount		*mp;
> +	struct xfs_inode		*dp;
> +	int				error;
>  
>  	trace_xfs_attr_sf_remove(args);
>  
>  	dp = args->dp;
>  	mp = dp->i_mount;
> -	base = sizeof(xfs_attr_sf_hdr_t);
>  	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
> -	sfe = &sf->list[0];
> -	end = sf->hdr.count;
> -	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
> -					base += size, i++) {
> -		size = XFS_ATTR_SF_ENTSIZE(sfe);
> -		if (sfe->namelen != args->name.len)
> -			continue;
> -		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
> -			continue;
> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> -			continue;
> -		break;
> -	}
> -	if (i == end)
> -		return -ENOATTR;
> +
> +	error = xfs_attr_shortform_hasname(args, &sfe, &base);
> +	if (error != -EEXIST)
> +		return error;
> +	size = XFS_ATTR_SF_ENTSIZE(sfe);
>  
>  	/*
>  	 * Fix up the attribute fork data, covering the hole
> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
> index 017480e..e108b37 100644
> --- a/fs/xfs/libxfs/xfs_attr_leaf.h
> +++ b/fs/xfs/libxfs/xfs_attr_leaf.h
> @@ -42,6 +42,8 @@ int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
>  int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
>  			struct xfs_buf **leaf_bp);
>  int	xfs_attr_shortform_remove(struct xfs_da_args *args);
> +int	xfs_attr_shortform_hasname(struct xfs_da_args *args,
> +			       struct xfs_attr_sf_entry **sfep, int *basep);
>  int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
>  int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
>  xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);
> -- 
> 2.7.4
>
Allison Henderson Nov. 8, 2019, 7:51 p.m. UTC | #2
On 11/8/19 12:32 PM, Darrick J. Wong wrote:
> On Wed, Nov 06, 2019 at 06:27:49PM -0700, Allison Collins wrote:
>> From: Allison Henderson <allison.henderson@oracle.com>
>>
>> This patch adds a new functions to check for the existence of
>> an attribute.  Subroutines are also added to handle the cases
>> of leaf blocks, nodes or shortform.  Common code that appears
>> in existing attr add and remove functions have been factored
>> out to help reduce the appearence of duplicated code.  We will
>> need these routines later for delayed attributes since delayed
>> operations cannot return error codes.
>>
>> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
>> ---
>>   fs/xfs/libxfs/xfs_attr.c      | 154 +++++++++++++++++++++++++++---------------
>>   fs/xfs/libxfs/xfs_attr.h      |   1 +
>>   fs/xfs/libxfs/xfs_attr_leaf.c | 107 ++++++++++++++++++-----------
>>   fs/xfs/libxfs/xfs_attr_leaf.h |   2 +
>>   4 files changed, 171 insertions(+), 93 deletions(-)
>>
>> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
>> index 5cb83a8..c8a3273 100644
>> --- a/fs/xfs/libxfs/xfs_attr.c
>> +++ b/fs/xfs/libxfs/xfs_attr.c
>> @@ -46,6 +46,7 @@ STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
>>   STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
>>   STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
>>   STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
>> +STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
>>   
>>   /*
>>    * Internal routines when attribute list is more than one block.
>> @@ -53,6 +54,8 @@ STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
>>   STATIC int xfs_attr_node_get(xfs_da_args_t *args);
>>   STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
>>   STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
>> +STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
>> +				 struct xfs_da_state **state);
>>   STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
>>   STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
>>   
>> @@ -310,6 +313,34 @@ xfs_attr_set_args(
>>   }
>>   
>>   /*
>> + * Return EEXIST if attr is found, or ENOATTR if not
>> + */
>> +int
>> +xfs_has_attr(
>> +	struct xfs_da_args      *args)
> 
> I was really hoping for a "replace ENOATTR/EEXIST with a boolean"
> cleanup at the end of this series, though as a straight hoisting and
> refactoring, this patch is ok for leaving the existing error code
> overloading. :)
> 
>> +{
>> +	struct xfs_inode        *dp = args->dp;
>> +	struct xfs_buf		*bp;
>> +	int                     error;
>> +
>> +	if (!xfs_inode_hasattr(dp)) {
>> +		error = -ENOATTR;
>> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
>> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
>> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
>> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
>> +		error = xfs_attr_leaf_hasname(args, &bp);
>> +		if (error != -ENOATTR && error != -EEXIST)
>> +			goto out;
>> +		xfs_trans_brelse(args->trans, bp);
>> +	} else {
>> +		error = xfs_attr_node_hasname(args, NULL);
>> +	}
>> +out:
>> +	return error;
>> +}
>> +
>> +/*
>>    * Remove the attribute specified in @args.
>>    */
>>   int
>> @@ -580,27 +611,20 @@ STATIC int
>>   xfs_attr_leaf_addname(
>>   	struct xfs_da_args	*args)
>>   {
>> -	struct xfs_inode	*dp;
>>   	struct xfs_buf		*bp;
>>   	int			retval, error, forkoff;
>> +	struct xfs_inode	*dp = args->dp;
>>   
>>   	trace_xfs_attr_leaf_addname(args);
>>   
>>   	/*
>> -	 * Read the (only) block in the attribute list in.
>> -	 */
>> -	dp = args->dp;
>> -	args->blkno = 0;
>> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
>> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
>> -	if (error)
>> -		return error;
>> -
>> -	/*
>>   	 * Look up the given attribute in the leaf block.  Figure out if
>>   	 * the given flags produce an error or call for an atomic rename.
>>   	 */
>> -	retval = xfs_attr3_leaf_lookup_int(bp, args);
>> +	retval = xfs_attr_leaf_hasname(args, &bp);
>> +	if (retval != -ENOATTR && retval != -EEXIST)
>> +		return retval;
>> +
>>   	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
>>   		xfs_trans_brelse(args->trans, bp);
>>   		return retval;
>> @@ -752,6 +776,24 @@ xfs_attr_leaf_addname(
>>   }
>>   
>>   /*
>> + * Return EEXIST if attr is found, or ENOATTR if not
>> + */
>> +STATIC int
>> +xfs_attr_leaf_hasname(
>> +	struct xfs_da_args      *args,
>> +	struct xfs_buf		**bp)
>> +{
>> +	int                     error = 0;
>> +
>> +	error = xfs_attr3_leaf_read(args->trans, args->dp, 0,
>> +				    XFS_DABUF_MAP_NOMAPPING, bp);
>> +	if (error)
>> +		return error;
>> +
>> +	return xfs_attr3_leaf_lookup_int(*bp, args);
>> +}
>> +
>> +/*
>>    * Remove a name from the leaf attribute list structure
>>    *
>>    * This leaf block cannot have a "remote" value, we only call this routine
>> @@ -771,13 +813,11 @@ xfs_attr_leaf_removename(
>>   	 * Remove the attribute.
>>   	 */
>>   	dp = args->dp;
>> -	args->blkno = 0;
>> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
>> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
>> -	if (error)
>> +
>> +	error = xfs_attr_leaf_hasname(args, &bp);
>> +	if (error != -ENOATTR && error != -EEXIST)
>>   		return error;
>>   
>> -	error = xfs_attr3_leaf_lookup_int(bp, args);
>>   	if (error == -ENOATTR) {
>>   		xfs_trans_brelse(args->trans, bp);
>>   		return error;
>> @@ -816,13 +856,10 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>>   
>>   	trace_xfs_attr_leaf_get(args);
>>   
>> -	args->blkno = 0;
>> -	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
>> -				    XFS_DABUF_MAP_NOMAPPING, &bp);
>> -	if (error)
>> +	error = xfs_attr_leaf_hasname(args, &bp);
>> +	if (error != -ENOATTR && error != -EEXIST)
>>   		return error;
>>   
>> -	error = xfs_attr3_leaf_lookup_int(bp, args);
>>   	if (error != -EEXIST)  {
>>   		xfs_trans_brelse(args->trans, bp);
>>   		return error;
>> @@ -832,6 +869,38 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>>   	return error;
>>   }
>>   
>> +/*
>> + * Return EEXIST if attr is found, or ENOATTR if not
>> + * statep: If not null is set to point at the found state.  Caller will
>> + * 	   be responsible for freeing the state in this case.
>> + */
>> +STATIC int
>> +xfs_attr_node_hasname(
>> +	struct xfs_da_args	*args,
>> +	struct xfs_da_state	**statep)
>> +{
>> +	struct xfs_da_state	*state;
>> +	int			retval, error;
>> +
>> +	state = xfs_da_state_alloc();
>> +	state->args = args;
>> +	state->mp = args->dp->i_mount;
>> +
>> +	/*
>> +	 * Search to see if name exists, and get back a pointer to it.
>> +	 */
>> +	error = xfs_da3_node_lookup_int(state, &retval);
>> +	if (error == 0)
>> +		error = retval;
>> +
>> +	if (statep != NULL)
>> +		*statep = state;
>> +	else
>> +		xfs_da_state_free(state);
>> +
>> +	return error;
>> +}
>> +
>>   /*========================================================================
>>    * External routines when attribute list size > geo->blksize
>>    *========================================================================*/
>> @@ -864,20 +933,17 @@ xfs_attr_node_addname(
>>   	dp = args->dp;
>>   	mp = dp->i_mount;
>>   restart:
>> -	state = xfs_da_state_alloc();
>> -	state->args = args;
>> -	state->mp = mp;
>> -
>>   	/*
>>   	 * Search to see if name already exists, and get back a pointer
>>   	 * to where it should go.
>>   	 */
>> -	error = xfs_da3_node_lookup_int(state, &retval);
>> -	if (error)
>> +	retval = xfs_attr_node_hasname(args, &state);
>> +	if (retval != -ENOATTR)
>>   		goto out;
>> +
>>   	blk = &state->path.blk[ state->path.active-1 ];
>>   	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
>> -	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
>> +	if (args->name.type & ATTR_REPLACE) {
>>   		goto out;
>>   	} else if (retval == -EEXIST) {
>>   		if (args->name.type & ATTR_CREATE)
>> @@ -1079,29 +1145,15 @@ xfs_attr_node_removename(
>>   {
>>   	struct xfs_da_state	*state;
>>   	struct xfs_da_state_blk	*blk;
>> -	struct xfs_inode	*dp;
>>   	struct xfs_buf		*bp;
>>   	int			retval, error, forkoff;
>> +	struct xfs_inode	*dp = args->dp;
>>   
>>   	trace_xfs_attr_node_removename(args);
>>   
>> -	/*
>> -	 * Tie a string around our finger to remind us where we are.
>> -	 */
>> -	dp = args->dp;
>> -	state = xfs_da_state_alloc();
>> -	state->args = args;
>> -	state->mp = dp->i_mount;
>> -
>> -	/*
>> -	 * Search to see if name exists, and get back a pointer to it.
>> -	 */
>> -	error = xfs_da3_node_lookup_int(state, &retval);
>> -	if (error || (retval != -EEXIST)) {
>> -		if (error == 0)
>> -			error = retval;
>> +	error = xfs_attr_node_hasname(args, &state);
>> +	if (error != -EEXIST)
>>   		goto out;
>> -	}
>>   
>>   	/*
>>   	 * If there is an out-of-line value, de-allocate the blocks.
>> @@ -1324,20 +1376,14 @@ xfs_attr_node_get(xfs_da_args_t *args)
>>   
>>   	trace_xfs_attr_node_get(args);
>>   
>> -	state = xfs_da_state_alloc();
>> -	state->args = args;
>> -	state->mp = args->dp->i_mount;
>> -
>>   	/*
>>   	 * Search to see if name exists, and get back a pointer to it.
>>   	 */
>> -	error = xfs_da3_node_lookup_int(state, &retval);
>> -	if (error) {
>> +	error = xfs_attr_node_hasname(args, &state);
>> +	if (error != -EEXIST) {
>>   		retval = error;
>>   		goto out_release;
>>   	}
>> -	if (retval != -EEXIST)
>> -		goto out_release;
>>   
>>   	/*
>>   	 * Get the value, local or "remote"
>> diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
>> index 44dd07a..3b5dad4 100644
>> --- a/fs/xfs/libxfs/xfs_attr.h
>> +++ b/fs/xfs/libxfs/xfs_attr.h
>> @@ -150,6 +150,7 @@ int xfs_attr_set(struct xfs_inode *dp, struct xfs_name *name,
>>   		 unsigned char *value, int valuelen, int flags);
>>   int xfs_attr_set_args(struct xfs_da_args *args);
>>   int xfs_attr_remove(struct xfs_inode *dp, struct xfs_name *name, int flags);
>> +int xfs_has_attr(struct xfs_da_args *args);
>>   int xfs_attr_remove_args(struct xfs_da_args *args);
>>   int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
>>   		  int flags, struct attrlist_cursor_kern *cursor);
>> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
>> index 93c3496..d06cfd6 100644
>> --- a/fs/xfs/libxfs/xfs_attr_leaf.c
>> +++ b/fs/xfs/libxfs/xfs_attr_leaf.c
>> @@ -655,18 +655,67 @@ xfs_attr_shortform_create(xfs_da_args_t *args)
>>   }
>>   
>>   /*
>> + * Return -EEXIST if attr is found, or -ENOATTR if not
>> + * args:  args containing attribute name and namelen
>> + * sfep:  If not null, pointer will be set to the last attr entry found on
>> +	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
>> + * basep: If not null, pointer is set to the byte offset of the entry in the
>> + *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
>> + *	  the last entry in the list
>> + */
>> +int
>> +xfs_attr_shortform_hasname(
>> +	struct xfs_da_args	 *args,
>> +	struct xfs_attr_sf_entry **sfep,
>> +	int			 *basep)
> 
> Byte offsets can't be negative, so this should be unsigned int.
> 
> Seeing as we also return the location of the sf entry and byte offset,
> maybe this ought to be called xfs_attr_sf_findname ?

Sure, will fix.

> 
>> +{
>> +	struct xfs_attr_shortform *sf;
>> +	struct xfs_attr_sf_entry *sfe;
>> +	int			base = sizeof(struct xfs_attr_sf_hdr);
>> +	int			size = 0;
>> +	int			end;
>> +	int			i;
>> +
>> +	base = sizeof(struct xfs_attr_sf_hdr);
>> +	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
>> +	sfe = &sf->list[0];
>> +	end = sf->hdr.count;
>> +	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
>> +			base += size, i++) {
>> +		size = XFS_ATTR_SF_ENTSIZE(sfe);
>> +		if (sfe->namelen != args->name.len)
>> +			continue;
>> +		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
>> +			continue;
>> +		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> +			continue;
>> +		break;
>> +	}
>> +
>> +	if (sfep != NULL)
>> +		*sfep = sfe;
>> +
>> +	if (basep != NULL)
>> +		*basep = base;
>> +
>> +	if (i == end)
>> +		return -ENOATTR;
>> +	return -EEXIST;
>> +}
>> +
>> +/*
>>    * Add a name/value pair to the shortform attribute list.
>>    * Overflow from the inode has already been checked for.
>>    */
>>   void
>>   xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>>   {
>> -	xfs_attr_shortform_t *sf;
>> -	xfs_attr_sf_entry_t *sfe;
>> -	int i, offset, size;
>> -	xfs_mount_t *mp;
>> -	xfs_inode_t *dp;
>> -	struct xfs_ifork *ifp;
>> +	struct xfs_attr_shortform	*sf;
>> +	struct xfs_attr_sf_entry	*sfe;
>> +	int				offset, size, error;
>> +	struct xfs_mount		*mp;
>> +	struct xfs_inode		*dp;
>> +	struct xfs_ifork		*ifp;
>>   
>>   	trace_xfs_attr_sf_add(args);
>>   
>> @@ -677,18 +726,8 @@ xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>>   	ifp = dp->i_afp;
>>   	ASSERT(ifp->if_flags & XFS_IFINLINE);
>>   	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
>> -	sfe = &sf->list[0];
>> -	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
>> -#ifdef DEBUG
>> -		if (sfe->namelen != args->name.len)
>> -			continue;
>> -		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
>> -			continue;
>> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> -			continue;
>> -		ASSERT(0);
>> -#endif
>> -	}
>> +	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
>> +	ASSERT(error != -EEXIST);
> 
> If this assertion triggers, the fs is corrupt and we need to log
> something and bail out.  5.5 for-next will soon have a new
> XFS_IS_CORRUPT macro that takes care of this, so you can do:
> 
> 	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
> 	if (XFS_IS_CORRUPT(mp, error != -EEXIST))
> 		return -EFSCORRUPTED;
> 
> --D
Ok, I will keep an eye out for that then.  Thanks!
Allison

> 
> 
>>   
>>   	offset = (char *)sfe - (char *)sf;
>>   	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
>> @@ -733,33 +772,23 @@ xfs_attr_fork_remove(
>>   int
>>   xfs_attr_shortform_remove(xfs_da_args_t *args)
>>   {
>> -	xfs_attr_shortform_t *sf;
>> -	xfs_attr_sf_entry_t *sfe;
>> -	int base, size=0, end, totsize, i;
>> -	xfs_mount_t *mp;
>> -	xfs_inode_t *dp;
>> +	struct xfs_attr_shortform	*sf;
>> +	struct xfs_attr_sf_entry	*sfe;
>> +	int				base, size = 0, end, totsize;
>> +	struct xfs_mount		*mp;
>> +	struct xfs_inode		*dp;
>> +	int				error;
>>   
>>   	trace_xfs_attr_sf_remove(args);
>>   
>>   	dp = args->dp;
>>   	mp = dp->i_mount;
>> -	base = sizeof(xfs_attr_sf_hdr_t);
>>   	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
>> -	sfe = &sf->list[0];
>> -	end = sf->hdr.count;
>> -	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
>> -					base += size, i++) {
>> -		size = XFS_ATTR_SF_ENTSIZE(sfe);
>> -		if (sfe->namelen != args->name.len)
>> -			continue;
>> -		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
>> -			continue;
>> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> -			continue;
>> -		break;
>> -	}
>> -	if (i == end)
>> -		return -ENOATTR;
>> +
>> +	error = xfs_attr_shortform_hasname(args, &sfe, &base);
>> +	if (error != -EEXIST)
>> +		return error;
>> +	size = XFS_ATTR_SF_ENTSIZE(sfe);
>>   
>>   	/*
>>   	 * Fix up the attribute fork data, covering the hole
>> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
>> index 017480e..e108b37 100644
>> --- a/fs/xfs/libxfs/xfs_attr_leaf.h
>> +++ b/fs/xfs/libxfs/xfs_attr_leaf.h
>> @@ -42,6 +42,8 @@ int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
>>   int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
>>   			struct xfs_buf **leaf_bp);
>>   int	xfs_attr_shortform_remove(struct xfs_da_args *args);
>> +int	xfs_attr_shortform_hasname(struct xfs_da_args *args,
>> +			       struct xfs_attr_sf_entry **sfep, int *basep);
>>   int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
>>   int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
>>   xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);
>> -- 
>> 2.7.4
>>
Brian Foster Nov. 11, 2019, 5:40 p.m. UTC | #3
On Wed, Nov 06, 2019 at 06:27:49PM -0700, Allison Collins wrote:
> From: Allison Henderson <allison.henderson@oracle.com>
> 
> This patch adds a new functions to check for the existence of
> an attribute.  Subroutines are also added to handle the cases
> of leaf blocks, nodes or shortform.  Common code that appears
> in existing attr add and remove functions have been factored
> out to help reduce the appearence of duplicated code.  We will
> need these routines later for delayed attributes since delayed
> operations cannot return error codes.
> 
> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> ---

This mostly looks good to me. Just some small nits..

>  fs/xfs/libxfs/xfs_attr.c      | 154 +++++++++++++++++++++++++++---------------
>  fs/xfs/libxfs/xfs_attr.h      |   1 +
>  fs/xfs/libxfs/xfs_attr_leaf.c | 107 ++++++++++++++++++-----------
>  fs/xfs/libxfs/xfs_attr_leaf.h |   2 +
>  4 files changed, 171 insertions(+), 93 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index 5cb83a8..c8a3273 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
...
> @@ -310,6 +313,34 @@ xfs_attr_set_args(
>  }
>  
>  /*
> + * Return EEXIST if attr is found, or ENOATTR if not
> + */
> +int
> +xfs_has_attr(
> +	struct xfs_da_args      *args)
> +{
> +	struct xfs_inode        *dp = args->dp;
> +	struct xfs_buf		*bp;
> +	int                     error;
> +
> +	if (!xfs_inode_hasattr(dp)) {
> +		error = -ENOATTR;
> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
> +		error = xfs_attr_leaf_hasname(args, &bp);
> +		if (error != -ENOATTR && error != -EEXIST)
> +			goto out;

Hmm.. is this basically an indirect check for whether bp is set? If so,
I think doing bp = NULL above and:

		if (bp)
			xfs_trans_brelse(args->trans, bp);

... is more straightforward.

> +		xfs_trans_brelse(args->trans, bp);
> +	} else {
> +		error = xfs_attr_node_hasname(args, NULL);
> +	}
> +out:
> +	return error;
> +}
> +
> +/*
>   * Remove the attribute specified in @args.
>   */
>  int
...
> @@ -832,6 +869,38 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>  	return error;
>  }
>  
> +/*
> + * Return EEXIST if attr is found, or ENOATTR if not
> + * statep: If not null is set to point at the found state.  Caller will
> + * 	   be responsible for freeing the state in this case.
> + */
> +STATIC int
> +xfs_attr_node_hasname(
> +	struct xfs_da_args	*args,
> +	struct xfs_da_state	**statep)
> +{
> +	struct xfs_da_state	*state;
> +	int			retval, error;
> +
> +	state = xfs_da_state_alloc();
> +	state->args = args;
> +	state->mp = args->dp->i_mount;
> +
> +	/*
> +	 * Search to see if name exists, and get back a pointer to it.
> +	 */
> +	error = xfs_da3_node_lookup_int(state, &retval);
> +	if (error == 0)
> +		error = retval;
> +
> +	if (statep != NULL)
> +		*statep = state;
> +	else
> +		xfs_da_state_free(state);
> +
> +	return error;
> +}

The state allocation handling is a little wonky here in the error
scenario. I think precedent is that if we're returning an unexpected
error, we should probably just free state directly rather than rely on
the caller to do so. If the function returns "success" (meaning -EEXIST
or -ENOATTR), then the caller owns the state memory. It might also make
sense to NULL init the pointer either at the top of this helper or the
caller.

> +
>  /*========================================================================
>   * External routines when attribute list size > geo->blksize
>   *========================================================================*/
...
> @@ -1324,20 +1376,14 @@ xfs_attr_node_get(xfs_da_args_t *args)
>  
>  	trace_xfs_attr_node_get(args);
>  
> -	state = xfs_da_state_alloc();
> -	state->args = args;
> -	state->mp = args->dp->i_mount;
> -
>  	/*
>  	 * Search to see if name exists, and get back a pointer to it.
>  	 */
> -	error = xfs_da3_node_lookup_int(state, &retval);
> -	if (error) {
> +	error = xfs_attr_node_hasname(args, &state);
> +	if (error != -EEXIST) {
>  		retval = error;

Can we kill retval in this function now? The only use is to assign error
to it.

>  		goto out_release;
>  	}
> -	if (retval != -EEXIST)
> -		goto out_release;
>  
>  	/*
>  	 * Get the value, local or "remote"
...
> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
> index 93c3496..d06cfd6 100644
> --- a/fs/xfs/libxfs/xfs_attr_leaf.c
> +++ b/fs/xfs/libxfs/xfs_attr_leaf.c
> @@ -655,18 +655,67 @@ xfs_attr_shortform_create(xfs_da_args_t *args)
>  }
>  
>  /*
> + * Return -EEXIST if attr is found, or -ENOATTR if not
> + * args:  args containing attribute name and namelen
> + * sfep:  If not null, pointer will be set to the last attr entry found on
> +	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
> + * basep: If not null, pointer is set to the byte offset of the entry in the
> + *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
> + *	  the last entry in the list
> + */
> +int
> +xfs_attr_shortform_hasname(
> +	struct xfs_da_args	 *args,
> +	struct xfs_attr_sf_entry **sfep,
> +	int			 *basep)
> +{
> +	struct xfs_attr_shortform *sf;
> +	struct xfs_attr_sf_entry *sfe;
> +	int			base = sizeof(struct xfs_attr_sf_hdr);
> +	int			size = 0;
> +	int			end;
> +	int			i;
> +
> +	base = sizeof(struct xfs_attr_sf_hdr);

Double init.

> +	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
> +	sfe = &sf->list[0];
> +	end = sf->hdr.count;
> +	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
> +			base += size, i++) {
> +		size = XFS_ATTR_SF_ENTSIZE(sfe);
> +		if (sfe->namelen != args->name.len)
> +			continue;
> +		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
> +			continue;
> +		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> +			continue;
> +		break;
> +	}
> +
> +	if (sfep != NULL)
> +		*sfep = sfe;
> +
> +	if (basep != NULL)
> +		*basep = base;
> +
> +	if (i == end)
> +		return -ENOATTR;
> +	return -EEXIST;
> +}
> +
> +/*
>   * Add a name/value pair to the shortform attribute list.
>   * Overflow from the inode has already been checked for.
>   */
>  void
>  xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>  {
> -	xfs_attr_shortform_t *sf;
> -	xfs_attr_sf_entry_t *sfe;
> -	int i, offset, size;
> -	xfs_mount_t *mp;
> -	xfs_inode_t *dp;
> -	struct xfs_ifork *ifp;
> +	struct xfs_attr_shortform	*sf;
> +	struct xfs_attr_sf_entry	*sfe;
> +	int				offset, size, error;
> +	struct xfs_mount		*mp;
> +	struct xfs_inode		*dp;
> +	struct xfs_ifork		*ifp;

Might as well fix up the typedef in the function signature (here and
below) as well.

Brian

>  
>  	trace_xfs_attr_sf_add(args);
>  
> @@ -677,18 +726,8 @@ xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>  	ifp = dp->i_afp;
>  	ASSERT(ifp->if_flags & XFS_IFINLINE);
>  	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
> -	sfe = &sf->list[0];
> -	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
> -#ifdef DEBUG
> -		if (sfe->namelen != args->name.len)
> -			continue;
> -		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
> -			continue;
> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> -			continue;
> -		ASSERT(0);
> -#endif
> -	}
> +	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
> +	ASSERT(error != -EEXIST);
>  
>  	offset = (char *)sfe - (char *)sf;
>  	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
> @@ -733,33 +772,23 @@ xfs_attr_fork_remove(
>  int
>  xfs_attr_shortform_remove(xfs_da_args_t *args)
>  {
> -	xfs_attr_shortform_t *sf;
> -	xfs_attr_sf_entry_t *sfe;
> -	int base, size=0, end, totsize, i;
> -	xfs_mount_t *mp;
> -	xfs_inode_t *dp;
> +	struct xfs_attr_shortform	*sf;
> +	struct xfs_attr_sf_entry	*sfe;
> +	int				base, size = 0, end, totsize;
> +	struct xfs_mount		*mp;
> +	struct xfs_inode		*dp;
> +	int				error;
>  
>  	trace_xfs_attr_sf_remove(args);
>  
>  	dp = args->dp;
>  	mp = dp->i_mount;
> -	base = sizeof(xfs_attr_sf_hdr_t);
>  	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
> -	sfe = &sf->list[0];
> -	end = sf->hdr.count;
> -	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
> -					base += size, i++) {
> -		size = XFS_ATTR_SF_ENTSIZE(sfe);
> -		if (sfe->namelen != args->name.len)
> -			continue;
> -		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
> -			continue;
> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
> -			continue;
> -		break;
> -	}
> -	if (i == end)
> -		return -ENOATTR;
> +
> +	error = xfs_attr_shortform_hasname(args, &sfe, &base);
> +	if (error != -EEXIST)
> +		return error;
> +	size = XFS_ATTR_SF_ENTSIZE(sfe);
>  
>  	/*
>  	 * Fix up the attribute fork data, covering the hole
> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
> index 017480e..e108b37 100644
> --- a/fs/xfs/libxfs/xfs_attr_leaf.h
> +++ b/fs/xfs/libxfs/xfs_attr_leaf.h
> @@ -42,6 +42,8 @@ int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
>  int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
>  			struct xfs_buf **leaf_bp);
>  int	xfs_attr_shortform_remove(struct xfs_da_args *args);
> +int	xfs_attr_shortform_hasname(struct xfs_da_args *args,
> +			       struct xfs_attr_sf_entry **sfep, int *basep);
>  int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
>  int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
>  xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);
> -- 
> 2.7.4
>
Christoph Hellwig Nov. 11, 2019, 5:53 p.m. UTC | #4
> +	if (!xfs_inode_hasattr(dp)) {
> +		error = -ENOATTR;
> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
> +		error = xfs_attr_leaf_hasname(args, &bp);
> +		if (error != -ENOATTR && error != -EEXIST)
> +			goto out;
> +		xfs_trans_brelse(args->trans, bp);
> +	} else {
> +		error = xfs_attr_node_hasname(args, NULL);
> +	}
> +out:
> +	return error;
> +}

I think a lot of this would be much simpler without the goto out, e.g.:

	if (!xfs_inode_hasattr(dp))
		return -ENOATTR;

	if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
		return xfs_attr_shortform_hasname(args, NULL, NULL);
	}

	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
		struct xfs_buf	*bp;
		int		error = xfs_attr_leaf_hasname(args, &bp);

		if (error == -ENOATTR || error == -EEXIST)
			xfs_trans_brelse(args->trans, bp);
		return error;
	}

	return xfs_attr_node_hasname(args, NULL);
Allison Henderson Nov. 11, 2019, 11:34 p.m. UTC | #5
On 11/11/19 10:40 AM, Brian Foster wrote:
> On Wed, Nov 06, 2019 at 06:27:49PM -0700, Allison Collins wrote:
>> From: Allison Henderson <allison.henderson@oracle.com>
>>
>> This patch adds a new functions to check for the existence of
>> an attribute.  Subroutines are also added to handle the cases
>> of leaf blocks, nodes or shortform.  Common code that appears
>> in existing attr add and remove functions have been factored
>> out to help reduce the appearence of duplicated code.  We will
>> need these routines later for delayed attributes since delayed
>> operations cannot return error codes.
>>
>> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
>> ---
> 
> This mostly looks good to me. Just some small nits..
> 
>>   fs/xfs/libxfs/xfs_attr.c      | 154 +++++++++++++++++++++++++++---------------
>>   fs/xfs/libxfs/xfs_attr.h      |   1 +
>>   fs/xfs/libxfs/xfs_attr_leaf.c | 107 ++++++++++++++++++-----------
>>   fs/xfs/libxfs/xfs_attr_leaf.h |   2 +
>>   4 files changed, 171 insertions(+), 93 deletions(-)
>>
>> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
>> index 5cb83a8..c8a3273 100644
>> --- a/fs/xfs/libxfs/xfs_attr.c
>> +++ b/fs/xfs/libxfs/xfs_attr.c
> ...
>> @@ -310,6 +313,34 @@ xfs_attr_set_args(
>>   }
>>   
>>   /*
>> + * Return EEXIST if attr is found, or ENOATTR if not
>> + */
>> +int
>> +xfs_has_attr(
>> +	struct xfs_da_args      *args)
>> +{
>> +	struct xfs_inode        *dp = args->dp;
>> +	struct xfs_buf		*bp;
>> +	int                     error;
>> +
>> +	if (!xfs_inode_hasattr(dp)) {
>> +		error = -ENOATTR;
>> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
>> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
>> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
>> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
>> +		error = xfs_attr_leaf_hasname(args, &bp);
>> +		if (error != -ENOATTR && error != -EEXIST)
>> +			goto out;
> 
> Hmm.. is this basically an indirect check for whether bp is set? If so,
> I think doing bp = NULL above and:
> 
> 		if (bp)
> 			xfs_trans_brelse(args->trans, bp);
> 
> ... is more straightforward.
> 
>> +		xfs_trans_brelse(args->trans, bp);
>> +	} else {
>> +		error = xfs_attr_node_hasname(args, NULL);
>> +	}
>> +out:
>> +	return error;
>> +}
>> +
>> +/*
>>    * Remove the attribute specified in @args.
>>    */
>>   int
> ...
>> @@ -832,6 +869,38 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
>>   	return error;
>>   }
>>   
>> +/*
>> + * Return EEXIST if attr is found, or ENOATTR if not
>> + * statep: If not null is set to point at the found state.  Caller will
>> + * 	   be responsible for freeing the state in this case.
>> + */
>> +STATIC int
>> +xfs_attr_node_hasname(
>> +	struct xfs_da_args	*args,
>> +	struct xfs_da_state	**statep)
>> +{
>> +	struct xfs_da_state	*state;
>> +	int			retval, error;
>> +
>> +	state = xfs_da_state_alloc();
>> +	state->args = args;
>> +	state->mp = args->dp->i_mount;
>> +
>> +	/*
>> +	 * Search to see if name exists, and get back a pointer to it.
>> +	 */
>> +	error = xfs_da3_node_lookup_int(state, &retval);
>> +	if (error == 0)
>> +		error = retval;
>> +
>> +	if (statep != NULL)
>> +		*statep = state;
>> +	else
>> +		xfs_da_state_free(state);
>> +
>> +	return error;
>> +}
> 
> The state allocation handling is a little wonky here in the error
> scenario. I think precedent is that if we're returning an unexpected
> error, we should probably just free state directly rather than rely on
> the caller to do so. If the function returns "success" (meaning -EEXIST
> or -ENOATTR), then the caller owns the state memory. It might also make
> sense to NULL init the pointer either at the top of this helper or the
> caller.
> 
>> +
>>   /*========================================================================
>>    * External routines when attribute list size > geo->blksize
>>    *========================================================================*/
> ...
>> @@ -1324,20 +1376,14 @@ xfs_attr_node_get(xfs_da_args_t *args)
>>   
>>   	trace_xfs_attr_node_get(args);
>>   
>> -	state = xfs_da_state_alloc();
>> -	state->args = args;
>> -	state->mp = args->dp->i_mount;
>> -
>>   	/*
>>   	 * Search to see if name exists, and get back a pointer to it.
>>   	 */
>> -	error = xfs_da3_node_lookup_int(state, &retval);
>> -	if (error) {
>> +	error = xfs_attr_node_hasname(args, &state);
>> +	if (error != -EEXIST) {
>>   		retval = error;
> 
> Can we kill retval in this function now? The only use is to assign error
> to it.
> 
>>   		goto out_release;
>>   	}
>> -	if (retval != -EEXIST)
>> -		goto out_release;
>>   
>>   	/*
>>   	 * Get the value, local or "remote"
> ...
>> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
>> index 93c3496..d06cfd6 100644
>> --- a/fs/xfs/libxfs/xfs_attr_leaf.c
>> +++ b/fs/xfs/libxfs/xfs_attr_leaf.c
>> @@ -655,18 +655,67 @@ xfs_attr_shortform_create(xfs_da_args_t *args)
>>   }
>>   
>>   /*
>> + * Return -EEXIST if attr is found, or -ENOATTR if not
>> + * args:  args containing attribute name and namelen
>> + * sfep:  If not null, pointer will be set to the last attr entry found on
>> +	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
>> + * basep: If not null, pointer is set to the byte offset of the entry in the
>> + *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
>> + *	  the last entry in the list
>> + */
>> +int
>> +xfs_attr_shortform_hasname(
>> +	struct xfs_da_args	 *args,
>> +	struct xfs_attr_sf_entry **sfep,
>> +	int			 *basep)
>> +{
>> +	struct xfs_attr_shortform *sf;
>> +	struct xfs_attr_sf_entry *sfe;
>> +	int			base = sizeof(struct xfs_attr_sf_hdr);
>> +	int			size = 0;
>> +	int			end;
>> +	int			i;
>> +
>> +	base = sizeof(struct xfs_attr_sf_hdr);
> 
> Double init.
> 
>> +	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
>> +	sfe = &sf->list[0];
>> +	end = sf->hdr.count;
>> +	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
>> +			base += size, i++) {
>> +		size = XFS_ATTR_SF_ENTSIZE(sfe);
>> +		if (sfe->namelen != args->name.len)
>> +			continue;
>> +		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
>> +			continue;
>> +		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> +			continue;
>> +		break;
>> +	}
>> +
>> +	if (sfep != NULL)
>> +		*sfep = sfe;
>> +
>> +	if (basep != NULL)
>> +		*basep = base;
>> +
>> +	if (i == end)
>> +		return -ENOATTR;
>> +	return -EEXIST;
>> +}
>> +
>> +/*
>>    * Add a name/value pair to the shortform attribute list.
>>    * Overflow from the inode has already been checked for.
>>    */
>>   void
>>   xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>>   {
>> -	xfs_attr_shortform_t *sf;
>> -	xfs_attr_sf_entry_t *sfe;
>> -	int i, offset, size;
>> -	xfs_mount_t *mp;
>> -	xfs_inode_t *dp;
>> -	struct xfs_ifork *ifp;
>> +	struct xfs_attr_shortform	*sf;
>> +	struct xfs_attr_sf_entry	*sfe;
>> +	int				offset, size, error;
>> +	struct xfs_mount		*mp;
>> +	struct xfs_inode		*dp;
>> +	struct xfs_ifork		*ifp;
> 
> Might as well fix up the typedef in the function signature (here and
> below) as well.
> 
> Brian

Sure, all the nits sound reasonable I will update them in the next 
version.  Thanks for the review!

Allison

> 
>>   
>>   	trace_xfs_attr_sf_add(args);
>>   
>> @@ -677,18 +726,8 @@ xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
>>   	ifp = dp->i_afp;
>>   	ASSERT(ifp->if_flags & XFS_IFINLINE);
>>   	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
>> -	sfe = &sf->list[0];
>> -	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
>> -#ifdef DEBUG
>> -		if (sfe->namelen != args->name.len)
>> -			continue;
>> -		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
>> -			continue;
>> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> -			continue;
>> -		ASSERT(0);
>> -#endif
>> -	}
>> +	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
>> +	ASSERT(error != -EEXIST);
>>   
>>   	offset = (char *)sfe - (char *)sf;
>>   	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
>> @@ -733,33 +772,23 @@ xfs_attr_fork_remove(
>>   int
>>   xfs_attr_shortform_remove(xfs_da_args_t *args)
>>   {
>> -	xfs_attr_shortform_t *sf;
>> -	xfs_attr_sf_entry_t *sfe;
>> -	int base, size=0, end, totsize, i;
>> -	xfs_mount_t *mp;
>> -	xfs_inode_t *dp;
>> +	struct xfs_attr_shortform	*sf;
>> +	struct xfs_attr_sf_entry	*sfe;
>> +	int				base, size = 0, end, totsize;
>> +	struct xfs_mount		*mp;
>> +	struct xfs_inode		*dp;
>> +	int				error;
>>   
>>   	trace_xfs_attr_sf_remove(args);
>>   
>>   	dp = args->dp;
>>   	mp = dp->i_mount;
>> -	base = sizeof(xfs_attr_sf_hdr_t);
>>   	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
>> -	sfe = &sf->list[0];
>> -	end = sf->hdr.count;
>> -	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
>> -					base += size, i++) {
>> -		size = XFS_ATTR_SF_ENTSIZE(sfe);
>> -		if (sfe->namelen != args->name.len)
>> -			continue;
>> -		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
>> -			continue;
>> -		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
>> -			continue;
>> -		break;
>> -	}
>> -	if (i == end)
>> -		return -ENOATTR;
>> +
>> +	error = xfs_attr_shortform_hasname(args, &sfe, &base);
>> +	if (error != -EEXIST)
>> +		return error;
>> +	size = XFS_ATTR_SF_ENTSIZE(sfe);
>>   
>>   	/*
>>   	 * Fix up the attribute fork data, covering the hole
>> diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
>> index 017480e..e108b37 100644
>> --- a/fs/xfs/libxfs/xfs_attr_leaf.h
>> +++ b/fs/xfs/libxfs/xfs_attr_leaf.h
>> @@ -42,6 +42,8 @@ int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
>>   int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
>>   			struct xfs_buf **leaf_bp);
>>   int	xfs_attr_shortform_remove(struct xfs_da_args *args);
>> +int	xfs_attr_shortform_hasname(struct xfs_da_args *args,
>> +			       struct xfs_attr_sf_entry **sfep, int *basep);
>>   int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
>>   int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
>>   xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);
>> -- 
>> 2.7.4
>>
>
Allison Henderson Nov. 11, 2019, 11:36 p.m. UTC | #6
On 11/11/19 10:53 AM, Christoph Hellwig wrote:
>> +	if (!xfs_inode_hasattr(dp)) {
>> +		error = -ENOATTR;
>> +	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
>> +		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
>> +		error = xfs_attr_shortform_hasname(args, NULL, NULL);
>> +	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
>> +		error = xfs_attr_leaf_hasname(args, &bp);
>> +		if (error != -ENOATTR && error != -EEXIST)
>> +			goto out;
>> +		xfs_trans_brelse(args->trans, bp);
>> +	} else {
>> +		error = xfs_attr_node_hasname(args, NULL);
>> +	}
>> +out:
>> +	return error;
>> +}
> 
> I think a lot of this would be much simpler without the goto out, e.g.:
> 
> 	if (!xfs_inode_hasattr(dp))
> 		return -ENOATTR;
> 
> 	if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
> 		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
> 		return xfs_attr_shortform_hasname(args, NULL, NULL);
> 	}
> 
> 	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
> 		struct xfs_buf	*bp;
> 		int		error = xfs_attr_leaf_hasname(args, &bp);
> 
> 		if (error == -ENOATTR || error == -EEXIST)
> 			xfs_trans_brelse(args->trans, bp);
> 		return error;
> 	}
> 
> 	return xfs_attr_node_hasname(args, NULL);
> 

Sure, will fix this along with Brians suggestions too.  Thanks!
Allison
diff mbox series

Patch

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 5cb83a8..c8a3273 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -46,6 +46,7 @@  STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
+STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
 
 /*
  * Internal routines when attribute list is more than one block.
@@ -53,6 +54,8 @@  STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
 STATIC int xfs_attr_node_get(xfs_da_args_t *args);
 STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
+STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
+				 struct xfs_da_state **state);
 STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
 STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
 
@@ -310,6 +313,34 @@  xfs_attr_set_args(
 }
 
 /*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ */
+int
+xfs_has_attr(
+	struct xfs_da_args      *args)
+{
+	struct xfs_inode        *dp = args->dp;
+	struct xfs_buf		*bp;
+	int                     error;
+
+	if (!xfs_inode_hasattr(dp)) {
+		error = -ENOATTR;
+	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
+		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
+		error = xfs_attr_shortform_hasname(args, NULL, NULL);
+	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
+		error = xfs_attr_leaf_hasname(args, &bp);
+		if (error != -ENOATTR && error != -EEXIST)
+			goto out;
+		xfs_trans_brelse(args->trans, bp);
+	} else {
+		error = xfs_attr_node_hasname(args, NULL);
+	}
+out:
+	return error;
+}
+
+/*
  * Remove the attribute specified in @args.
  */
 int
@@ -580,27 +611,20 @@  STATIC int
 xfs_attr_leaf_addname(
 	struct xfs_da_args	*args)
 {
-	struct xfs_inode	*dp;
 	struct xfs_buf		*bp;
 	int			retval, error, forkoff;
+	struct xfs_inode	*dp = args->dp;
 
 	trace_xfs_attr_leaf_addname(args);
 
 	/*
-	 * Read the (only) block in the attribute list in.
-	 */
-	dp = args->dp;
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
-				    XFS_DABUF_MAP_NOMAPPING, &bp);
-	if (error)
-		return error;
-
-	/*
 	 * Look up the given attribute in the leaf block.  Figure out if
 	 * the given flags produce an error or call for an atomic rename.
 	 */
-	retval = xfs_attr3_leaf_lookup_int(bp, args);
+	retval = xfs_attr_leaf_hasname(args, &bp);
+	if (retval != -ENOATTR && retval != -EEXIST)
+		return retval;
+
 	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
 		xfs_trans_brelse(args->trans, bp);
 		return retval;
@@ -752,6 +776,24 @@  xfs_attr_leaf_addname(
 }
 
 /*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ */
+STATIC int
+xfs_attr_leaf_hasname(
+	struct xfs_da_args      *args,
+	struct xfs_buf		**bp)
+{
+	int                     error = 0;
+
+	error = xfs_attr3_leaf_read(args->trans, args->dp, 0,
+				    XFS_DABUF_MAP_NOMAPPING, bp);
+	if (error)
+		return error;
+
+	return xfs_attr3_leaf_lookup_int(*bp, args);
+}
+
+/*
  * Remove a name from the leaf attribute list structure
  *
  * This leaf block cannot have a "remote" value, we only call this routine
@@ -771,13 +813,11 @@  xfs_attr_leaf_removename(
 	 * Remove the attribute.
 	 */
 	dp = args->dp;
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
-				    XFS_DABUF_MAP_NOMAPPING, &bp);
-	if (error)
+
+	error = xfs_attr_leaf_hasname(args, &bp);
+	if (error != -ENOATTR && error != -EEXIST)
 		return error;
 
-	error = xfs_attr3_leaf_lookup_int(bp, args);
 	if (error == -ENOATTR) {
 		xfs_trans_brelse(args->trans, bp);
 		return error;
@@ -816,13 +856,10 @@  xfs_attr_leaf_get(xfs_da_args_t *args)
 
 	trace_xfs_attr_leaf_get(args);
 
-	args->blkno = 0;
-	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
-				    XFS_DABUF_MAP_NOMAPPING, &bp);
-	if (error)
+	error = xfs_attr_leaf_hasname(args, &bp);
+	if (error != -ENOATTR && error != -EEXIST)
 		return error;
 
-	error = xfs_attr3_leaf_lookup_int(bp, args);
 	if (error != -EEXIST)  {
 		xfs_trans_brelse(args->trans, bp);
 		return error;
@@ -832,6 +869,38 @@  xfs_attr_leaf_get(xfs_da_args_t *args)
 	return error;
 }
 
+/*
+ * Return EEXIST if attr is found, or ENOATTR if not
+ * statep: If not null is set to point at the found state.  Caller will
+ * 	   be responsible for freeing the state in this case.
+ */
+STATIC int
+xfs_attr_node_hasname(
+	struct xfs_da_args	*args,
+	struct xfs_da_state	**statep)
+{
+	struct xfs_da_state	*state;
+	int			retval, error;
+
+	state = xfs_da_state_alloc();
+	state->args = args;
+	state->mp = args->dp->i_mount;
+
+	/*
+	 * Search to see if name exists, and get back a pointer to it.
+	 */
+	error = xfs_da3_node_lookup_int(state, &retval);
+	if (error == 0)
+		error = retval;
+
+	if (statep != NULL)
+		*statep = state;
+	else
+		xfs_da_state_free(state);
+
+	return error;
+}
+
 /*========================================================================
  * External routines when attribute list size > geo->blksize
  *========================================================================*/
@@ -864,20 +933,17 @@  xfs_attr_node_addname(
 	dp = args->dp;
 	mp = dp->i_mount;
 restart:
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = mp;
-
 	/*
 	 * Search to see if name already exists, and get back a pointer
 	 * to where it should go.
 	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error)
+	retval = xfs_attr_node_hasname(args, &state);
+	if (retval != -ENOATTR)
 		goto out;
+
 	blk = &state->path.blk[ state->path.active-1 ];
 	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
-	if ((args->name.type & ATTR_REPLACE) && (retval == -ENOATTR)) {
+	if (args->name.type & ATTR_REPLACE) {
 		goto out;
 	} else if (retval == -EEXIST) {
 		if (args->name.type & ATTR_CREATE)
@@ -1079,29 +1145,15 @@  xfs_attr_node_removename(
 {
 	struct xfs_da_state	*state;
 	struct xfs_da_state_blk	*blk;
-	struct xfs_inode	*dp;
 	struct xfs_buf		*bp;
 	int			retval, error, forkoff;
+	struct xfs_inode	*dp = args->dp;
 
 	trace_xfs_attr_node_removename(args);
 
-	/*
-	 * Tie a string around our finger to remind us where we are.
-	 */
-	dp = args->dp;
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = dp->i_mount;
-
-	/*
-	 * Search to see if name exists, and get back a pointer to it.
-	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error || (retval != -EEXIST)) {
-		if (error == 0)
-			error = retval;
+	error = xfs_attr_node_hasname(args, &state);
+	if (error != -EEXIST)
 		goto out;
-	}
 
 	/*
 	 * If there is an out-of-line value, de-allocate the blocks.
@@ -1324,20 +1376,14 @@  xfs_attr_node_get(xfs_da_args_t *args)
 
 	trace_xfs_attr_node_get(args);
 
-	state = xfs_da_state_alloc();
-	state->args = args;
-	state->mp = args->dp->i_mount;
-
 	/*
 	 * Search to see if name exists, and get back a pointer to it.
 	 */
-	error = xfs_da3_node_lookup_int(state, &retval);
-	if (error) {
+	error = xfs_attr_node_hasname(args, &state);
+	if (error != -EEXIST) {
 		retval = error;
 		goto out_release;
 	}
-	if (retval != -EEXIST)
-		goto out_release;
 
 	/*
 	 * Get the value, local or "remote"
diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index 44dd07a..3b5dad4 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -150,6 +150,7 @@  int xfs_attr_set(struct xfs_inode *dp, struct xfs_name *name,
 		 unsigned char *value, int valuelen, int flags);
 int xfs_attr_set_args(struct xfs_da_args *args);
 int xfs_attr_remove(struct xfs_inode *dp, struct xfs_name *name, int flags);
+int xfs_has_attr(struct xfs_da_args *args);
 int xfs_attr_remove_args(struct xfs_da_args *args);
 int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
 		  int flags, struct attrlist_cursor_kern *cursor);
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 93c3496..d06cfd6 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -655,18 +655,67 @@  xfs_attr_shortform_create(xfs_da_args_t *args)
 }
 
 /*
+ * Return -EEXIST if attr is found, or -ENOATTR if not
+ * args:  args containing attribute name and namelen
+ * sfep:  If not null, pointer will be set to the last attr entry found on
+	  -EEXIST.  On -ENOATTR pointer is left at the last entry in the list
+ * basep: If not null, pointer is set to the byte offset of the entry in the
+ *	  list on -EEXIST.  On -ENOATTR, pointer is left at the byte offset of
+ *	  the last entry in the list
+ */
+int
+xfs_attr_shortform_hasname(
+	struct xfs_da_args	 *args,
+	struct xfs_attr_sf_entry **sfep,
+	int			 *basep)
+{
+	struct xfs_attr_shortform *sf;
+	struct xfs_attr_sf_entry *sfe;
+	int			base = sizeof(struct xfs_attr_sf_hdr);
+	int			size = 0;
+	int			end;
+	int			i;
+
+	base = sizeof(struct xfs_attr_sf_hdr);
+	sf = (struct xfs_attr_shortform *)args->dp->i_afp->if_u1.if_data;
+	sfe = &sf->list[0];
+	end = sf->hdr.count;
+	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
+			base += size, i++) {
+		size = XFS_ATTR_SF_ENTSIZE(sfe);
+		if (sfe->namelen != args->name.len)
+			continue;
+		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
+			continue;
+		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
+			continue;
+		break;
+	}
+
+	if (sfep != NULL)
+		*sfep = sfe;
+
+	if (basep != NULL)
+		*basep = base;
+
+	if (i == end)
+		return -ENOATTR;
+	return -EEXIST;
+}
+
+/*
  * Add a name/value pair to the shortform attribute list.
  * Overflow from the inode has already been checked for.
  */
 void
 xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
 {
-	xfs_attr_shortform_t *sf;
-	xfs_attr_sf_entry_t *sfe;
-	int i, offset, size;
-	xfs_mount_t *mp;
-	xfs_inode_t *dp;
-	struct xfs_ifork *ifp;
+	struct xfs_attr_shortform	*sf;
+	struct xfs_attr_sf_entry	*sfe;
+	int				offset, size, error;
+	struct xfs_mount		*mp;
+	struct xfs_inode		*dp;
+	struct xfs_ifork		*ifp;
 
 	trace_xfs_attr_sf_add(args);
 
@@ -677,18 +726,8 @@  xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
 	ifp = dp->i_afp;
 	ASSERT(ifp->if_flags & XFS_IFINLINE);
 	sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
-	sfe = &sf->list[0];
-	for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
-#ifdef DEBUG
-		if (sfe->namelen != args->name.len)
-			continue;
-		if (memcmp(args->name.name, sfe->nameval, args->name.len) != 0)
-			continue;
-		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
-			continue;
-		ASSERT(0);
-#endif
-	}
+	error = xfs_attr_shortform_hasname(args, &sfe, NULL);
+	ASSERT(error != -EEXIST);
 
 	offset = (char *)sfe - (char *)sf;
 	size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen);
@@ -733,33 +772,23 @@  xfs_attr_fork_remove(
 int
 xfs_attr_shortform_remove(xfs_da_args_t *args)
 {
-	xfs_attr_shortform_t *sf;
-	xfs_attr_sf_entry_t *sfe;
-	int base, size=0, end, totsize, i;
-	xfs_mount_t *mp;
-	xfs_inode_t *dp;
+	struct xfs_attr_shortform	*sf;
+	struct xfs_attr_sf_entry	*sfe;
+	int				base, size = 0, end, totsize;
+	struct xfs_mount		*mp;
+	struct xfs_inode		*dp;
+	int				error;
 
 	trace_xfs_attr_sf_remove(args);
 
 	dp = args->dp;
 	mp = dp->i_mount;
-	base = sizeof(xfs_attr_sf_hdr_t);
 	sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
-	sfe = &sf->list[0];
-	end = sf->hdr.count;
-	for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
-					base += size, i++) {
-		size = XFS_ATTR_SF_ENTSIZE(sfe);
-		if (sfe->namelen != args->name.len)
-			continue;
-		if (memcmp(sfe->nameval, args->name.name, args->name.len) != 0)
-			continue;
-		if (!xfs_attr_namesp_match(args->name.type, sfe->flags))
-			continue;
-		break;
-	}
-	if (i == end)
-		return -ENOATTR;
+
+	error = xfs_attr_shortform_hasname(args, &sfe, &base);
+	if (error != -EEXIST)
+		return error;
+	size = XFS_ATTR_SF_ENTSIZE(sfe);
 
 	/*
 	 * Fix up the attribute fork data, covering the hole
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
index 017480e..e108b37 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.h
+++ b/fs/xfs/libxfs/xfs_attr_leaf.h
@@ -42,6 +42,8 @@  int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
 int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
 			struct xfs_buf **leaf_bp);
 int	xfs_attr_shortform_remove(struct xfs_da_args *args);
+int	xfs_attr_shortform_hasname(struct xfs_da_args *args,
+			       struct xfs_attr_sf_entry **sfep, int *basep);
 int	xfs_attr_shortform_allfit(struct xfs_buf *bp, struct xfs_inode *dp);
 int	xfs_attr_shortform_bytesfit(struct xfs_inode *dp, int bytes);
 xfs_failaddr_t xfs_attr_shortform_verify(struct xfs_inode *ip);