Re: [PATCH v3 13/19] xfs: Add delay context to xfs_da_args

[Brian Foster <bfoster@redhat.com>]

On Thu, Sep 05, 2019 at 03:18:31PM -0700, Allison Collins wrote:
> This patch adds a new struct xfs_delay_context, which we
> will use to keep track of the current state of a delayed
> attribute operation.
> 
> The flags member is used to track various operations that
> are in progress so that we know not to repeat them, and
> resume where we left off before EAGAIN was returned to
> cycle out the transaction.  Other members take the place
> of local variables that need to retain their values
> across multiple function recalls.
> 
> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> ---

Ok, I'll have to get further along in the usage of these bits to fully
grok this one. One quick note in the meantime...

>  fs/xfs/libxfs/xfs_da_btree.h | 23 +++++++++++++++++++++++
>  fs/xfs/scrub/common.c        |  2 ++
>  fs/xfs/xfs_acl.c             |  2 ++
>  fs/xfs/xfs_attr_list.c       |  1 +
>  fs/xfs/xfs_ioctl.c           |  2 ++
>  fs/xfs/xfs_ioctl32.c         |  2 ++
>  fs/xfs/xfs_iops.c            |  2 ++
>  fs/xfs/xfs_xattr.c           |  1 +
>  8 files changed, 35 insertions(+)
> 
> diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h
> index bed4f40..ebe1295 100644
> --- a/fs/xfs/libxfs/xfs_da_btree.h
> +++ b/fs/xfs/libxfs/xfs_da_btree.h
> @@ -42,6 +42,28 @@ enum xfs_dacmp {
>  	XFS_CMP_CASE		/* names are same but differ in case */
>  };
>  
> +#define		XFS_DC_INIT		0x01 /* Init delay info */
> +#define		XFS_DC_FOUND_LBLK	0x02 /* We found leaf blk for attr */
> +#define		XFS_DC_FOUND_NBLK	0x04 /* We found node blk for attr */
> +#define		XFS_DC_ALLOC_LEAF	0x08 /* We are allocating leaf blocks */
> +#define		XFS_DC_ALLOC_NODE	0x10 /* We are allocating node blocks */
> +#define		XFS_DC_RM_LEAF_BLKS	0x20 /* We are removing leaf blocks */
> +#define		XFS_DC_RM_NODE_BLKS	0x40 /* We are removing node blocks */
> +
> +/*
> + * Context used for keeping track of delayed attribute operations
> + */
> +struct xfs_delay_context {
> +	unsigned int		flags;
> +	struct xfs_buf		*leaf_bp;
> +	struct xfs_bmbt_irec	map;
> +	xfs_dablk_t		lblkno;
> +	xfs_fileoff_t		lfileoff;
> +	int			blkcnt;
> +	struct xfs_da_state	*state;
> +	struct xfs_da_state_blk *blk;
> +};
> +

The mixed size of the various fields leaves some holes in the structure.
See 'pahole xfs.ko' output for how this struct could be reordered to
reduce the overall size a bit..

Brian

>  /*
>   * Structure to ease passing around component names.
>   */
> @@ -69,6 +91,7 @@ typedef struct xfs_da_args {
>  	int		rmtvaluelen2;	/* remote attr value length in bytes */
>  	int		op_flags;	/* operation flags */
>  	enum xfs_dacmp	cmpresult;	/* name compare result for lookups */
> +	struct xfs_delay_context  dc;	/* context used for delay attr ops */
>  } xfs_da_args_t;
>  
>  /*
> diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
> index 1887605..9a649d1 100644
> --- a/fs/xfs/scrub/common.c
> +++ b/fs/xfs/scrub/common.c
> @@ -24,6 +24,8 @@
>  #include "xfs_rmap_btree.h"
>  #include "xfs_log.h"
>  #include "xfs_trans_priv.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  #include "xfs_reflink.h"
>  #include "scrub/scrub.h"
> diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
> index f8fb6e10..4e85b38 100644
> --- a/fs/xfs/xfs_acl.c
> +++ b/fs/xfs/xfs_acl.c
> @@ -10,6 +10,8 @@
>  #include "xfs_trans_resv.h"
>  #include "xfs_mount.h"
>  #include "xfs_inode.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  #include "xfs_trace.h"
>  #include <linux/posix_acl_xattr.h>
> diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c
> index 00758fd..467c53c 100644
> --- a/fs/xfs/xfs_attr_list.c
> +++ b/fs/xfs/xfs_attr_list.c
> @@ -12,6 +12,7 @@
>  #include "xfs_trans_resv.h"
>  #include "xfs_mount.h"
>  #include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_inode.h"
>  #include "xfs_trans.h"
>  #include "xfs_bmap.h"
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 626420d..2cabdc2 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -15,6 +15,8 @@
>  #include "xfs_iwalk.h"
>  #include "xfs_itable.h"
>  #include "xfs_error.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  #include "xfs_bmap.h"
>  #include "xfs_bmap_util.h"
> diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
> index 1e08bf7..7153780 100644
> --- a/fs/xfs/xfs_ioctl32.c
> +++ b/fs/xfs/xfs_ioctl32.c
> @@ -17,6 +17,8 @@
>  #include "xfs_itable.h"
>  #include "xfs_fsops.h"
>  #include "xfs_rtalloc.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  #include "xfs_ioctl.h"
>  #include "xfs_ioctl32.h"
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 469e8e2..57de5f1 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -13,6 +13,8 @@
>  #include "xfs_inode.h"
>  #include "xfs_acl.h"
>  #include "xfs_quota.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  #include "xfs_trans.h"
>  #include "xfs_trace.h"
> diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
> index 6309da4..470e605 100644
> --- a/fs/xfs/xfs_xattr.c
> +++ b/fs/xfs/xfs_xattr.c
> @@ -10,6 +10,7 @@
>  #include "xfs_log_format.h"
>  #include "xfs_da_format.h"
>  #include "xfs_inode.h"
> +#include "xfs_da_btree.h"
>  #include "xfs_attr.h"
>  
>  #include <linux/posix_acl_xattr.h>
> -- 
> 2.7.4
>