Re: [PATCH v13 05/10] xfs: Set up infastructure for deferred attribute operations

Darrick J. Wong
2020-11-10T21:52:05Z

On Thu, Oct 22, 2020 at 11:34:30PM -0700, Allison Henderson wrote:
> Currently attributes are modified directly across one or more
> transactions. But they are not logged or replayed in the event of an
> error. The goal of delayed attributes is to enable logging and replaying
> of attribute operations using the existing delayed operations
> infrastructure. This will later enable the attributes to become part of
> larger multi part operations that also must first be recorded to the
> log. This is mostly of interest in the scheme of parent pointers which
> would need to maintain an attribute containing parent inode information
> any time an inode is moved, created, or removed. Parent pointers would
> then be of interest to any feature that would need to quickly derive an
> inode path from the mount point. Online scrub, nfs lookups and fs grow
> or shrink operations are all features that could take advantage of this.
>
> This patch adds two new log item types for setting or removing
> attributes as deferred operations. The xfs_attri_log_item logs an
> intent to set or remove an attribute. The corresponding
> xfs_attrd_log_item holds a reference to the xfs_attri_log_item and is
> freed once the transaction is done. Both log items use a generic
> xfs_attr_log_format structure that contains the attribute name, value,
> flags, inode, and an op_flag that indicates if the operations is a set
> or remove.
>
> Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
> ---
> fs/xfs/Makefile | 1 +
> fs/xfs/libxfs/xfs_attr.c | 7 +-
> fs/xfs/libxfs/xfs_attr.h | 19 +
> fs/xfs/libxfs/xfs_defer.c | 1 +
> fs/xfs/libxfs/xfs_defer.h | 3 +
> fs/xfs/libxfs/xfs_format.h | 5 +
> fs/xfs/libxfs/xfs_log_format.h | 44 ++-
> fs/xfs/libxfs/xfs_log_recover.h | 2 +
> fs/xfs/libxfs/xfs_types.h | 1 +
> fs/xfs/scrub/common.c | 2 +
> fs/xfs/xfs_acl.c | 2 +
> fs/xfs/xfs_attr_item.c | 750 ++++++++++++++++++++++++++++++++++++++++
> fs/xfs/xfs_attr_item.h | 76 ++++
> 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_log.c | 4 +
> fs/xfs/xfs_log_recover.c | 2 +
> fs/xfs/xfs_ondisk.h | 2 +
> fs/xfs/xfs_xattr.c | 1 +
> 21 files changed, 923 insertions(+), 6 deletions(-)
>
> diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
> index 04611a1..b056cfc 100644
> --- a/fs/xfs/Makefile
> +++ b/fs/xfs/Makefile
> @@ -102,6 +102,7 @@ xfs-y += xfs_log.o \
> xfs_buf_item_recover.o \
> xfs_dquot_item_recover.o \
> xfs_extfree_item.o \
> + xfs_attr_item.o \
> xfs_icreate_item.o \
> xfs_inode_item.o \
> xfs_inode_item_recover.o \
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index 6453178..760383c 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -24,6 +24,7 @@
> #include "xfs_quota.h"
> #include "xfs_trans_space.h"
> #include "xfs_trace.h"
> +#include "xfs_attr_item.h"
>
> /*
> * xfs_attr.c
> @@ -59,8 +60,6 @@ STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
> STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
> STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
> STATIC int xfs_attr_leaf_try_add(struct xfs_da_args *args, struct xfs_buf *bp);
> -STATIC int xfs_attr_set_iter(struct xfs_delattr_context *dac,
> - struct xfs_buf **leaf_bp);
>
> int
> xfs_inode_hasattr(
> @@ -142,7 +141,7 @@ xfs_attr_get(
> /*
> * Calculate how many blocks we need for the new attribute,
> */
> -STATIC int
> +int
> xfs_attr_calc_size(
> struct xfs_da_args *args,
> int *local)
> @@ -327,7 +326,7 @@ xfs_attr_set_args(
> * to handle this, and recall the function until a successful error code is
> * returned.
> */
> -STATIC int
> +int
> xfs_attr_set_iter(
> struct xfs_delattr_context *dac,
> struct xfs_buf **leaf_bp)
> diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
> index 501f9df..5b4a1ca 100644
> --- a/fs/xfs/libxfs/xfs_attr.h
> +++ b/fs/xfs/libxfs/xfs_attr.h
> @@ -247,6 +247,7 @@ enum xfs_delattr_state {
> #define XFS_DAC_DEFER_FINISH 0x01 /* finish the transaction */
> #define XFS_DAC_NODE_RMVNAME_INIT 0x02 /* xfs_attr_node_removename init */
> #define XFS_DAC_LEAF_ADDNAME_INIT 0x04 /* xfs_attr_leaf_addname init*/
> +#define XFS_DAC_DELAYED_OP_INIT 0x08 /* delayed operations init*/
>
> /*
> * Context used for keeping track of delayed attribute operations
> @@ -254,6 +255,9 @@ enum xfs_delattr_state {
> struct xfs_delattr_context {
> struct xfs_da_args *da_args;
>
> + /* Used by delayed attributes to hold leaf across transactions */

"Used by xfs_attr_set to hold a leaf buffer across a transaction roll" ?

> + struct xfs_buf *leaf_bp;
> +
> /* Used in xfs_attr_rmtval_set_blk to roll through allocating blocks */
> struct xfs_bmbt_irec map;
> xfs_dablk_t lblkno;
> @@ -267,6 +271,18 @@ struct xfs_delattr_context {
> enum xfs_delattr_state dela_state;
> };
>
> +/*
> + * List of attrs to commit later.
> + */
> +struct xfs_attr_item {
> + struct xfs_delattr_context xattri_dac;
> + uint32_t xattri_op_flags;/* attr op set or rm */

The comment for xattri_op_flags should be more direct in mentioning that
it takes XFS_ATTR_OP_FLAGS_{SET,REMOVE}.

(Alternately you could define an enum for the incore state tracker that
causes the appropriate XFS_ATTR_OP_FLAG* to be set on the log item in
xfs_attr_create_intent to avoid mixing of the flag namespaces, but that
is a lot of paper-pushing...)

> +
> + /* used to log this item to an intent */
> + struct list_head xattri_list;
> +};

Ok, so going back to a confusing comment I had from the last series,
I'm glad that you've moved all the attr code to be deferred operations.

Can you move all the xfs_delattr_context fields into xfs_attr_item?
AFAICT (from git diff'ing the entire branch :P) we never allocate an
xfs_delattr_context on its own; we only ever access the one that's
embedded in xfs_attr_item, right?

> +
> +
> /*========================================================================
> * Function prototypes for the kernel.
> *========================================================================*/
> @@ -282,11 +298,14 @@ int xfs_attr_get_ilocked(struct xfs_da_args *args);
> int xfs_attr_get(struct xfs_da_args *args);
> int xfs_attr_set(struct xfs_da_args *args);
> int xfs_attr_set_args(struct xfs_da_args *args);
> +int xfs_attr_set_iter(struct xfs_delattr_context *dac,
> + struct xfs_buf **leaf_bp);
> int xfs_has_attr(struct xfs_da_args *args);
> int xfs_attr_remove_args(struct xfs_da_args *args);
> int xfs_attr_remove_iter(struct xfs_delattr_context *dac);
> bool xfs_attr_namecheck(const void *name, size_t length);
> void xfs_delattr_context_init(struct xfs_delattr_context *dac,
> struct xfs_da_args *args);
> +int xfs_attr_calc_size(struct xfs_da_args *args, int *local);
>
> #endif /* __XFS_ATTR_H__ */
> diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c
> index eff4a12..e9caff7 100644
> --- a/fs/xfs/libxfs/xfs_defer.c
> +++ b/fs/xfs/libxfs/xfs_defer.c
> @@ -178,6 +178,7 @@ static const struct xfs_defer_op_type *defer_op_types[] = {
> [XFS_DEFER_OPS_TYPE_RMAP] = &xfs_rmap_update_defer_type,
> [XFS_DEFER_OPS_TYPE_FREE] = &xfs_extent_free_defer_type,
> [XFS_DEFER_OPS_TYPE_AGFL_FREE] = &xfs_agfl_free_defer_type,
> + [XFS_DEFER_OPS_TYPE_ATTR] = &xfs_attr_defer_type,
> };
>
> static void
> diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h
> index 05472f7..72a5789 100644
> --- a/fs/xfs/libxfs/xfs_defer.h
> +++ b/fs/xfs/libxfs/xfs_defer.h
> @@ -19,6 +19,7 @@ enum xfs_defer_ops_type {
> XFS_DEFER_OPS_TYPE_RMAP,
> XFS_DEFER_OPS_TYPE_FREE,
> XFS_DEFER_OPS_TYPE_AGFL_FREE,
> + XFS_DEFER_OPS_TYPE_ATTR,
> XFS_DEFER_OPS_TYPE_MAX,
> };
>
> @@ -63,6 +64,8 @@ extern const struct xfs_defer_op_type xfs_refcount_update_defer_type;
> extern const struct xfs_defer_op_type xfs_rmap_update_defer_type;
> extern const struct xfs_defer_op_type xfs_extent_free_defer_type;
> extern const struct xfs_defer_op_type xfs_agfl_free_defer_type;
> +extern const struct xfs_defer_op_type xfs_attr_defer_type;
> +
>
> /*
> * This structure enables a dfops user to detach the chain of deferred
> diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
> index dd764da..d419c34 100644
> --- a/fs/xfs/libxfs/xfs_format.h
> +++ b/fs/xfs/libxfs/xfs_format.h
> @@ -584,6 +584,11 @@ static inline bool xfs_sb_version_hasinobtcounts(struct xfs_sb *sbp)
> (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_INOBTCNT);
> }
>
> +static inline bool xfs_sb_version_hasdelattr(struct xfs_sb *sbp)
> +{
> + return false;
> +}
> +
> /*
> * end of superblock version macros
> */
> diff --git a/fs/xfs/libxfs/xfs_log_format.h b/fs/xfs/libxfs/xfs_log_format.h
> index 8bd00da..de6309d 100644
> --- a/fs/xfs/libxfs/xfs_log_format.h
> +++ b/fs/xfs/libxfs/xfs_log_format.h
> @@ -117,7 +117,12 @@ struct xfs_unmount_log_format {
> #define XLOG_REG_TYPE_CUD_FORMAT 24
> #define XLOG_REG_TYPE_BUI_FORMAT 25
> #define XLOG_REG_TYPE_BUD_FORMAT 26
> -#define XLOG_REG_TYPE_MAX 26
> +#define XLOG_REG_TYPE_ATTRI_FORMAT 27
> +#define XLOG_REG_TYPE_ATTRD_FORMAT 28
> +#define XLOG_REG_TYPE_ATTR_NAME 29
> +#define XLOG_REG_TYPE_ATTR_VALUE 30
> +#define XLOG_REG_TYPE_MAX 30
> +
>
> /*
> * Flags to log operation header
> @@ -240,6 +245,8 @@ typedef struct xfs_trans_header {
> #define XFS_LI_CUD 0x1243
> #define XFS_LI_BUI 0x1244 /* bmbt update intent */
> #define XFS_LI_BUD 0x1245
> +#define XFS_LI_ATTRI 0x1246 /* attr set/remove intent*/
> +#define XFS_LI_ATTRD 0x1247 /* attr set/remove done */
>
> #define XFS_LI_TYPE_DESC \
> { XFS_LI_EFI, "XFS_LI_EFI" }, \
> @@ -255,7 +262,9 @@ typedef struct xfs_trans_header {
> { XFS_LI_CUI, "XFS_LI_CUI" }, \
> { XFS_LI_CUD, "XFS_LI_CUD" }, \
> { XFS_LI_BUI, "XFS_LI_BUI" }, \
> - { XFS_LI_BUD, "XFS_LI_BUD" }
> + { XFS_LI_BUD, "XFS_LI_BUD" }, \
> + { XFS_LI_ATTRI, "XFS_LI_ATTRI" }, \
> + { XFS_LI_ATTRD, "XFS_LI_ATTRD" }
>
> /*
> * Inode Log Item Format definitions.
> @@ -863,4 +872,35 @@ struct xfs_icreate_log {
> __be32 icl_gen; /* inode generation number to use */
> };
>
> +/*
> + * Flags for deferred attribute operations.
> + * Upper bits are flags, lower byte is type code
> + */
> +#define XFS_ATTR_OP_FLAGS_SET 1 /* Set the attribute */
> +#define XFS_ATTR_OP_FLAGS_REMOVE 2 /* Remove the attribute */
> +#define XFS_ATTR_OP_FLAGS_TYPE_MASK 0x0FF /* Flags type mask */
> +
> +/*
> + * This is the structure used to lay out an attr log item in the
> + * log.
> + */
> +struct xfs_attri_log_format {
> + uint16_t alfi_type; /* attri log item type */
> + uint16_t alfi_size; /* size of this item */
> + uint32_t __pad; /* pad to 64 bit aligned */
> + uint64_t alfi_id; /* attri identifier */
> + xfs_ino_t alfi_ino; /* the inode for this attr operation */

This is an ondisk structure; please use only explicitly sized data
types like uint64_t.

> + uint32_t alfi_op_flags; /* marks the op as a set or remove */
> + uint32_t alfi_name_len; /* attr name length */
> + uint32_t alfi_value_len; /* attr value length */
> + uint32_t alfi_attr_flags;/* attr flags */
> +};
> +
> +struct xfs_attrd_log_format {
> + uint16_t alfd_type; /* attrd log item type */
> + uint16_t alfd_size; /* size of this item */
> + uint32_t __pad; /* pad to 64 bit aligned */
> + uint64_t alfd_alf_id; /* id of corresponding attrd */

"..of corresponding attri"

> +};
> +
> #endif /* __XFS_LOG_FORMAT_H__ */
> diff --git a/fs/xfs/libxfs/xfs_log_recover.h b/fs/xfs/libxfs/xfs_log_recover.h
> index 3cca2bf..b6e5514 100644
> --- a/fs/xfs/libxfs/xfs_log_recover.h
> +++ b/fs/xfs/libxfs/xfs_log_recover.h
> @@ -72,6 +72,8 @@ extern const struct xlog_recover_item_ops xlog_rui_item_ops;
> extern const struct xlog_recover_item_ops xlog_rud_item_ops;
> extern const struct xlog_recover_item_ops xlog_cui_item_ops;
> extern const struct xlog_recover_item_ops xlog_cud_item_ops;
> +extern const struct xlog_recover_item_ops xlog_attri_item_ops;
> +extern const struct xlog_recover_item_ops xlog_attrd_item_ops;
>
> /*
> * Macros, structures, prototypes for internal log manager use.
> diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h
> index 397d947..860cdd2 100644
> --- a/fs/xfs/libxfs/xfs_types.h
> +++ b/fs/xfs/libxfs/xfs_types.h
> @@ -11,6 +11,7 @@ typedef uint32_t prid_t; /* project ID */
> typedef uint32_t xfs_agblock_t; /* blockno in alloc. group */
> typedef uint32_t xfs_agino_t; /* inode # within allocation grp */
> typedef uint32_t xfs_extlen_t; /* extent length in blocks */
> +typedef uint32_t xfs_attrlen_t; /* attr length */

This doesn't get used anywhere.

> typedef uint32_t xfs_agnumber_t; /* allocation group number */
> typedef int32_t xfs_extnum_t; /* # of extents in a file */
> typedef int16_t xfs_aextnum_t; /* # extents in an attribute fork */
> 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 c544951..cad1db4 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 "xfs_error.h"
> diff --git a/fs/xfs/xfs_attr_item.c b/fs/xfs/xfs_attr_item.c
> new file mode 100644
> index 0000000..3980066
> --- /dev/null
> +++ b/fs/xfs/xfs_attr_item.c
> @@ -0,0 +1,750 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2019 Oracle. All Rights Reserved.

2019 -> 2020.

> + * Author: Allison Collins <allison.henderson@oracle.com>
> + */
> +
> +#include "xfs.h"
> +#include "xfs_fs.h"
> +#include "xfs_format.h"
> +#include "xfs_log_format.h"
> +#include "xfs_trans_resv.h"
> +#include "xfs_bit.h"
> +#include "xfs_shared.h"
> +#include "xfs_mount.h"
> +#include "xfs_defer.h"
> +#include "xfs_trans.h"
> +#include "xfs_trans_priv.h"
> +#include "xfs_buf_item.h"
> +#include "xfs_attr_item.h"
> +#include "xfs_log.h"
> +#include "xfs_btree.h"
> +#include "xfs_rmap.h"
> +#include "xfs_inode.h"
> +#include "xfs_icache.h"
> +#include "xfs_da_format.h"
> +#include "xfs_da_btree.h"
> +#include "xfs_attr.h"
> +#include "xfs_shared.h"
> +#include "xfs_attr_item.h"
> +#include "xfs_alloc.h"
> +#include "xfs_bmap.h"
> +#include "xfs_trace.h"
> +#include "libxfs/xfs_da_format.h"
> +#include "xfs_inode.h"
> +#include "xfs_quota.h"
> +#include "xfs_log_priv.h"
> +#include "xfs_log_recover.h"
> +
> +static const struct xfs_item_ops xfs_attri_item_ops;
> +static const struct xfs_item_ops xfs_attrd_item_ops;
> +
> +static inline struct xfs_attri_log_item *ATTRI_ITEM(struct xfs_log_item *lip)
> +{
> + return container_of(lip, struct xfs_attri_log_item, attri_item);
> +}
> +
> +STATIC void
> +xfs_attri_item_free(
> + struct xfs_attri_log_item *attrip)
> +{
> + kmem_free(attrip->attri_item.li_lv_shadow);
> + kmem_free(attrip);
> +}
> +
> +/*
> + * Freeing the attrip requires that we remove it from the AIL if it has already
> + * been placed there. However, the ATTRI may not yet have been placed in the
> + * AIL when called by xfs_attri_release() from ATTRD processing due to the
> + * ordering of committed vs unpin operations in bulk insert operations. Hence
> + * the reference count to ensure only the last caller frees the ATTRI.
> + */
> +STATIC void
> +xfs_attri_release(
> + struct xfs_attri_log_item *attrip)
> +{
> + ASSERT(atomic_read(&attrip->attri_refcount) > 0);
> + if (atomic_dec_and_test(&attrip->attri_refcount)) {
> + xfs_trans_ail_delete(&attrip->attri_item,
> + SHUTDOWN_LOG_IO_ERROR);
> + xfs_attri_item_free(attrip);
> + }
> +}
> +
> +/*
> + * This returns the number of iovecs needed to log the given attri item. We
> + * only need 1 iovec for an attri item. It just logs the attr_log_format
> + * structure.
> + */
> +static inline int
> +xfs_attri_item_sizeof(
> + struct xfs_attri_log_item *attrip)
> +{
> + return sizeof(struct xfs_attri_log_format);
> +}

Please get rid of this trivial oneliner.

> +
> +STATIC void
> +xfs_attri_item_size(
> + struct xfs_log_item *lip,
> + int *nvecs,
> + int *nbytes)
> +{
> + struct xfs_attri_log_item *attrip = ATTRI_ITEM(lip);
> +
> + *nvecs += 1;
> + *nbytes += xfs_attri_item_sizeof(attrip);
> +
> + /* Attr set and remove operations require a name */
> + ASSERT(attrip->attri_name_len > 0);
> +
> + *nvecs += 1;
> + *nbytes += ATTR_NVEC_SIZE(attrip->attri_name_len);
> +
> + /*
> + * Set ops can accept a value of 0 len to clear an attr value. Remove
> + * ops do not need a value at all. So only account for the value
> + * when it is needed.
> + */
> + if (attrip->attri_value_len > 0) {
> + *nvecs += 1;
> + *nbytes += ATTR_NVEC_SIZE(attrip->attri_value_len);
> + }
> +}
> +
> +/*
> + * This is called to fill in the log iovecs for the given attri log
> + * item. We use 1 iovec for the attri_format_item, 1 for the name, and
> + * another for the value if it is present
> + */
> +STATIC void
> +xfs_attri_item_format(
> + struct xfs_log_item *lip,
> + struct xfs_log_vec *lv)
> +{
> + struct xfs_attri_log_item *attrip = ATTRI_ITEM(lip);
> + struct xfs_log_iovec *vecp = NULL;
> +
> + attrip->attri_format.alfi_type = XFS_LI_ATTRI;
> + attrip->attri_format.alfi_size = 1;
> +
> + /*
> + * This size accounting must be done before copying the attrip into the
> + * iovec. If we do it after, the wrong size will be recorded to the log
> + * and we trip across assertion checks for bad region sizes later during
> + * the log recovery.
> + */
> +
> + ASSERT(attrip->attri_name_len > 0);
> + attrip->attri_format.alfi_size++;
> +
> + if (attrip->attri_value_len > 0)
> + attrip->attri_format.alfi_size++;
> +
> + xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ATTRI_FORMAT,
> + &attrip->attri_format,
> + xfs_attri_item_sizeof(attrip));
> + if (attrip->attri_name_len > 0)

I thought we required attri_name_len > 0 always?

> + xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ATTR_NAME,
> + attrip->attri_name,
> + ATTR_NVEC_SIZE(attrip->attri_name_len));
> +
> + if (attrip->attri_value_len > 0)
> + xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ATTR_VALUE,
> + attrip->attri_value,
> + ATTR_NVEC_SIZE(attrip->attri_value_len));
> +}
> +
> +/*
> + * The unpin operation is the last place an ATTRI is manipulated in the log. It
> + * is either inserted in the AIL or aborted in the event of a log I/O error. In
> + * either case, the ATTRI transaction has been successfully committed to make
> + * it this far. Therefore, we expect whoever committed the ATTRI to either
> + * construct and commit the ATTRD or drop the ATTRD's reference in the event of
> + * error. Simply drop the log's ATTRI reference now that the log is done with
> + * it.
> + */
> +STATIC void
> +xfs_attri_item_unpin(
> + struct xfs_log_item *lip,
> + int remove)
> +{
> + struct xfs_attri_log_item *attrip = ATTRI_ITEM(lip);
> +
> + xfs_attri_release(attrip);

Nit: this could be shortened to xfs_attri_release(ATTRI_ITEM(lip)).

> +}
> +
> +
> +STATIC void
> +xfs_attri_item_release(
> + struct xfs_log_item *lip)
> +{
> + xfs_attri_release(ATTRI_ITEM(lip));
> +}
> +
> +/*
> + * Allocate and initialize an attri item
> + */
> +STATIC struct xfs_attri_log_item *
> +xfs_attri_init(
> + struct xfs_mount *mp)
> +
> +{
> + struct xfs_attri_log_item *attrip;
> + uint size;

Can you line up the *mp in the parameter list with the *attrip in the
local variables?

> +
> + size = (uint)(sizeof(struct xfs_attri_log_item));

kmem_zalloc takes a size_t parameter (which is the return type of sizeof);
no need to do all this casting.

> + attrip = kmem_zalloc(size, 0);
> +
> + xfs_log_item_init(mp, &attrip->attri_item, XFS_LI_ATTRI,
> + &xfs_attri_item_ops);
> + attrip->attri_format.alfi_id = (uintptr_t)(void *)attrip;
> + atomic_set(&attrip->attri_refcount, 2);
> +
> + return attrip;
> +}
> +
> +/*
> + * Copy an attr format buffer from the given buf, and into the destination attr
> + * format structure.
> + */
> +STATIC int
> +xfs_attri_copy_format(struct xfs_log_iovec *buf,
> + struct xfs_attri_log_format *dst_attr_fmt)
> +{
> + struct xfs_attri_log_format *src_attr_fmt = buf->i_addr;
> + uint len = sizeof(struct xfs_attri_log_format);

Indentation and whatnot with the parameter names.

> +
> + if (buf->i_len != len)
> + return -EFSCORRUPTED;
> +
> + memcpy((char *)dst_attr_fmt, (char *)src_attr_fmt, len);
> + return 0;
> +}
> +
> +static inline struct xfs_attrd_log_item *ATTRD_ITEM(struct xfs_log_item *lip)
> +{
> + return container_of(lip, struct xfs_attrd_log_item, attrd_item);
> +}
> +
> +STATIC void
> +xfs_attrd_item_free(struct xfs_attrd_log_item *attrdp)
> +{
> + kmem_free(attrdp->attrd_item.li_lv_shadow);
> + kmem_free(attrdp);
> +}
> +
> +/*
> + * This returns the number of iovecs needed to log the given attrd item.
> + * We only need 1 iovec for an attrd item. It just logs the attr_log_format
> + * structure.
> + */
> +static inline int
> +xfs_attrd_item_sizeof(
> + struct xfs_attrd_log_item *attrdp)
> +{
> + return sizeof(struct xfs_attrd_log_format);
> +}
> +
> +STATIC void
> +xfs_attrd_item_size(
> + struct xfs_log_item *lip,
> + int *nvecs,
> + int *nbytes)
> +{
> + struct xfs_attrd_log_item *attrdp = ATTRD_ITEM(lip);

Variable name alignment between the parameter list and the local vars.

> + *nvecs += 1;

Space between local variable declaration and the first line of code.

> + *nbytes += xfs_attrd_item_sizeof(attrdp);

No need for a oneliner function for sizeof.

> +}
> +
> +/*
> + * This is called to fill in the log iovecs for the given attrd log item. We use
> + * only 1 iovec for the attrd_format, and we point that at the attr_log_format
> + * structure embedded in the attrd item.
> + */
> +STATIC void
> +xfs_attrd_item_format(
> + struct xfs_log_item *lip,
> + struct xfs_log_vec *lv)
> +{
> + struct xfs_attrd_log_item *attrdp = ATTRD_ITEM(lip);
> + struct xfs_log_iovec *vecp = NULL;
> +
> + attrdp->attrd_format.alfd_type = XFS_LI_ATTRD;
> + attrdp->attrd_format.alfd_size = 1;
> +
> + xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ATTRD_FORMAT,
> + &attrdp->attrd_format, xfs_attrd_item_sizeof(attrdp));
> +}
> +
> +/*
> + * The ATTRD is either committed or aborted if the transaction is cancelled. If
> + * the transaction is cancelled, drop our reference to the ATTRI and free the
> + * ATTRD.
> + */
> +STATIC void
> +xfs_attrd_item_release(
> + struct xfs_log_item *lip)
> +{
> + struct xfs_attrd_log_item *attrdp = ATTRD_ITEM(lip);
> + xfs_attri_release(attrdp->attrd_attrip);

Space between the variable declaration and the first line of code.

> + xfs_attrd_item_free(attrdp);
> +}
> +
> +/*
> + * Log an ATTRI it to the ATTRD when the attr op is done. An attr operation

I don't know what "Log an ATTRI it to the ATTRD" means. I think this is
the function that performs one step of an attribute update intent and
then tags the attrd item dirty, right?

> + * may be a set or a remove. Note that the transaction is marked dirty
> + * regardless of whether the operation succeeds or fails to support the
> + * ATTRI/ATTRD lifecycle rules.
> + */
> +int
> +xfs_trans_attr(
> + struct xfs_delattr_context *dac,
> + struct xfs_attrd_log_item *attrdp,
> + struct xfs_buf **leaf_bp,
> + uint32_t op_flags)
> +{
> + struct xfs_da_args *args = dac->da_args;
> + int error;
> +
> + error = xfs_qm_dqattach_locked(args->dp, 0);
> + if (error)
> + return error;
> +
> + switch (op_flags) {
> + case XFS_ATTR_OP_FLAGS_SET:
> + args->op_flags |= XFS_DA_OP_ADDNAME;
> + error = xfs_attr_set_iter(dac, leaf_bp);
> + break;
> + case XFS_ATTR_OP_FLAGS_REMOVE:
> + ASSERT(XFS_IFORK_Q((args->dp)));

No need for the double parentheses around args->dp.

> + error = xfs_attr_remove_iter(dac);
> + break;
> + default:
> + error = -EFSCORRUPTED;
> + break;
> + }
> +
> + /*
> + * Mark the transaction dirty, even on error. This ensures the
> + * transaction is aborted, which:
> + *
> + * 1.) releases the ATTRI and frees the ATTRD
> + * 2.) shuts down the filesystem
> + */
> + args->trans->t_flags |= XFS_TRANS_DIRTY;
> + if (xfs_sb_version_hasdelattr(&args->dp->i_mount->m_sb))
> + set_bit(XFS_LI_DIRTY, &attrdp->attrd_item.li_flags);

This could probably be:

if (attrdp)
set_bit(...);

> +
> + return error;
> +}
> +
> +/* Log an attr to the intent item. */
> +STATIC void
> +xfs_attr_log_item(
> + struct xfs_trans *tp,
> + struct xfs_attri_log_item *attrip,
> + struct xfs_attr_item *attr)
> +{
> + struct xfs_attri_log_format *attrp;
> +
> + tp->t_flags |= XFS_TRANS_DIRTY;
> + set_bit(XFS_LI_DIRTY, &attrip->attri_item.li_flags);
> +
> + /*
> + * At this point the xfs_attr_item has been constructed, and we've
> + * created the log intent. Fill in the attri log item and log format
> + * structure with fields from this xfs_attr_item
> + */
> + attrp = &attrip->attri_format;
> + attrp->alfi_ino = attr->xattri_dac.da_args->dp->i_ino;
> + attrp->alfi_op_flags = attr->xattri_op_flags;
> + attrp->alfi_value_len = attr->xattri_dac.da_args->valuelen;
> + attrp->alfi_name_len = attr->xattri_dac.da_args->namelen;
> + attrp->alfi_attr_flags = attr->xattri_dac.da_args->attr_filter;
> +
> + attrip->attri_name = (void *)attr->xattri_dac.da_args->name;
> + attrip->attri_value = attr->xattri_dac.da_args->value;
> + attrip->attri_name_len = attr->xattri_dac.da_args->namelen;
> + attrip->attri_value_len = attr->xattri_dac.da_args->valuelen;
> +}
> +
> +/* Get an ATTRI. */
> +static struct xfs_log_item *
> +xfs_attr_create_intent(
> + struct xfs_trans *tp,
> + struct list_head *items,
> + unsigned int count,
> + bool sort)
> +{
> + struct xfs_mount *mp = tp->t_mountp;
> + struct xfs_attri_log_item *attrip;
> + struct xfs_attr_item *attr;
> +
> + ASSERT(count == 1);
> +
> + if (!xfs_sb_version_hasdelattr(&mp->m_sb))
> + return NULL;
> +
> + attrip = xfs_attri_init(mp);
> + xfs_trans_add_item(tp, &attrip->attri_item);
> + list_for_each_entry(attr, items, xattri_list)
> + xfs_attr_log_item(tp, attrip, attr);
> + return &attrip->attri_item;
> +}
> +
> +/* Process an attr. */
> +STATIC int
> +xfs_attr_finish_item(
> + struct xfs_trans *tp,
> + struct xfs_log_item *done,
> + struct list_head *item,
> + struct xfs_btree_cur **state)
> +{
> + struct xfs_attr_item *attr;
> + int error;
> + struct xfs_delattr_context *dac;
> + struct xfs_attrd_log_item *attrdp;
> + struct xfs_attri_log_item *attrip;
> +
> + attr = container_of(item, struct xfs_attr_item, xattri_list);
> + dac = &attr->xattri_dac;
> +
> + /*
> + * Always reset trans after EAGAIN cycle
> + * since the transaction is new
> + */
> + dac->da_args->trans = tp;
> +
> + error = xfs_trans_attr(dac, ATTRD_ITEM(done), &dac->leaf_bp,
> + attr->xattri_op_flags);
> + /*
> + * The attrip refers to xfs_attr_item memory to log the name and value
> + * with the intent item. This already occurred when the intent was
> + * committed so these fields are no longer accessed.

Can you clear the attri_{name,value} pointers after you've logged the
intent item so that we don't have to do them here?

> Clear them out of
> + * caution since we're about to free the xfs_attr_item.
> + */
> + if (xfs_sb_version_hasdelattr(&dac->da_args->dp->i_mount->m_sb)) {
> + attrdp = (struct xfs_attrd_log_item *)done;

attrdp = ATTRD_ITEM(done)?

> + attrip = attrdp->attrd_attrip;
> + attrip->attri_name = NULL;
> + attrip->attri_value = NULL;
> + }
> +
> + if (error != -EAGAIN)
> + kmem_free(attr);
> +
> + return error;
> +}
> +
> +/* Abort all pending ATTRs. */
> +STATIC void
> +xfs_attr_abort_intent(
> + struct xfs_log_item *intent)
> +{
> + xfs_attri_release(ATTRI_ITEM(intent));
> +}
> +
> +/* Cancel an attr */
> +STATIC void
> +xfs_attr_cancel_item(
> + struct list_head *item)
> +{
> + struct xfs_attr_item *attr;
> +
> + attr = container_of(item, struct xfs_attr_item, xattri_list);
> + kmem_free(attr);
> +}
> +
> +/*
> + * The ATTRI is logged only once and cannot be moved in the log, so simply
> + * return the lsn at which it's been logged.
> + */
> +STATIC xfs_lsn_t
> +xfs_attri_item_committed(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> + return lsn;
> +}

You can omit this function because the default is "return lsn;" if you
don't provide one. See xfs_trans_committed_bulk.

> +
> +STATIC void
> +xfs_attri_item_committing(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> +}

This function isn't required if it doesn't do anything. See
xfs_log_commit_cil.

> +
> +STATIC bool
> +xfs_attri_item_match(
> + struct xfs_log_item *lip,
> + uint64_t intent_id)
> +{
> + return ATTRI_ITEM(lip)->attri_format.alfi_id == intent_id;
> +}
> +
> +/*
> + * When the attrd item is committed to disk, all we need to do is delete our
> + * reference to our partner attri item and then free ourselves. Since we're
> + * freeing ourselves we must return -1 to keep the transaction code from
> + * further referencing this item.
> + */
> +STATIC xfs_lsn_t
> +xfs_attrd_item_committed(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> + struct xfs_attrd_log_item *attrdp = ATTRD_ITEM(lip);
> +
> + /*
> + * Drop the ATTRI reference regardless of whether the ATTRD has been
> + * aborted. Once the ATTRD transaction is constructed, it is the sole
> + * responsibility of the ATTRD to release the ATTRI (even if the ATTRI
> + * is aborted due to log I/O error).
> + */
> + xfs_attri_release(attrdp->attrd_attrip);
> + xfs_attrd_item_free(attrdp);
> +
> + return NULLCOMMITLSN;
> +}

If you set XFS_ITEM_RELEASE_WHEN_COMMITTED in the attrd item ops,
xfs_trans_committed_bulk will call ->iop_release instead of
->iop_committed and you therefore don't need this function.

> +
> +STATIC void
> +xfs_attrd_item_committing(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> +}

Same comment as xfs_attri_item_committing.

> +
> +
> +/*
> + * Allocate and initialize an attrd item
> + */
> +struct xfs_attrd_log_item *
> +xfs_attrd_init(
> + struct xfs_mount *mp,
> + struct xfs_attri_log_item *attrip)
> +
> +{
> + struct xfs_attrd_log_item *attrdp;
> + uint size;
> +
> + size = (uint)(sizeof(struct xfs_attrd_log_item));

Same comment about sizeof and size_t as in xfs_attri_init.

> + attrdp = kmem_zalloc(size, 0);
> + memset(attrdp, 0, size);

No need to memset-zero something you just zalloc'd.

> +
> + xfs_log_item_init(mp, &attrdp->attrd_item, XFS_LI_ATTRD,
> + &xfs_attrd_item_ops);
> + attrdp->attrd_attrip = attrip;
> + attrdp->attrd_format.alfd_alf_id = attrip->attri_format.alfi_id;
> +
> + return attrdp;
> +}
> +
> +/*
> + * This routine is called to allocate an "attr free done" log item.
> + */
> +struct xfs_attrd_log_item *
> +xfs_trans_get_attrd(struct xfs_trans *tp,
> + struct xfs_attri_log_item *attrip)
> +{
> + struct xfs_attrd_log_item *attrdp;
> +
> + ASSERT(tp != NULL);
> +
> + attrdp = xfs_attrd_init(tp->t_mountp, attrip);
> + ASSERT(attrdp != NULL);

You could fold xfs_attrd_init into this function since there's only one
caller.

> +
> + xfs_trans_add_item(tp, &attrdp->attrd_item);
> + return attrdp;
> +}
> +
> +static const struct xfs_item_ops xfs_attrd_item_ops = {
> + .iop_size = xfs_attrd_item_size,
> + .iop_format = xfs_attrd_item_format,
> + .iop_release = xfs_attrd_item_release,
> + .iop_committing = xfs_attrd_item_committing,
> + .iop_committed = xfs_attrd_item_committed,
> +};
> +
> +
> +/* Get an ATTRD so we can process all the attrs. */
> +static struct xfs_log_item *
> +xfs_attr_create_done(
> + struct xfs_trans *tp,
> + struct xfs_log_item *intent,
> + unsigned int count)
> +{
> + if (!xfs_sb_version_hasdelattr(&tp->t_mountp->m_sb))
> + return NULL;

This is probably better expressed as:

if (!intent)
return NULL;

Since we don't need a log intent done item if there's no log intent
item.

> +
> + return &xfs_trans_get_attrd(tp, ATTRI_ITEM(intent))->attrd_item;
> +}
> +
> +const struct xfs_defer_op_type xfs_attr_defer_type = {
> + .max_items = 1,
> + .create_intent = xfs_attr_create_intent,
> + .abort_intent = xfs_attr_abort_intent,
> + .create_done = xfs_attr_create_done,
> + .finish_item = xfs_attr_finish_item,
> + .cancel_item = xfs_attr_cancel_item,
> +};
> +
> +/*
> + * Process an attr intent item that was recovered from the log. We need to
> + * delete the attr that it describes.
> + */
> +STATIC int
> +xfs_attri_item_recover(
> + struct xfs_log_item *lip,
> + struct list_head *capture_list)
> +{
> + struct xfs_attri_log_item *attrip = ATTRI_ITEM(lip);
> + struct xfs_mount *mp = lip->li_mountp;
> + struct xfs_inode *ip;
> + struct xfs_da_args args;
> + struct xfs_attri_log_format *attrp;
> + int error;
> +
> + /*
> + * First check the validity of the attr described by the ATTRI. If any
> + * are bad, then assume that all are bad and just toss the ATTRI.
> + */
> + attrp = &attrip->attri_format;
> + if (!(attrp->alfi_op_flags == XFS_ATTR_OP_FLAGS_SET ||
> + attrp->alfi_op_flags == XFS_ATTR_OP_FLAGS_REMOVE) ||
> + (attrp->alfi_value_len > XATTR_SIZE_MAX) ||
> + (attrp->alfi_name_len > XATTR_NAME_MAX) ||
> + (attrp->alfi_name_len == 0)) {

This needs to call xfs_verify_ino() on attrp->alfi_ino.

This also needs to check for xfs_sb_version_hasdelayedattr().

I would refactor this into a separate validation predicate to eliminate
the multi-line if statement. I will post a series cleaning up the other
log items' recover functions shortly.

> + /*
> + * This will pull the ATTRI from the AIL and free the memory
> + * associated with it.
> + */
> + xfs_attri_release(attrip);

No need to call xfs_attri_release; one of the 5.10 cleanups was to
recognize that the log recovery code does this for you automatically.

> + return -EFSCORRUPTED;
> + }
> +
> + error = xfs_iget(mp, 0, attrp->alfi_ino, 0, 0, &ip);
> + if (error)
> + return error;

I /think/ this needs to call xfs_qm_dqattach here, for reasons I'll get
into shortly.

In the meantime, this /definitely/ needs to do:

if (VFS_I(ip)->i_nlink == 0)
xfs_iflags_set(ip, XFS_IRECOVERY);

Because the IRECOVERY flag prevents inode inactivation from triggering
on an unlinked inode while we're still performing log recovery.

If you want to steal the xlog_recover_iget helper from the atomic
swapext series[0] please feel free. :)

[0] https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git/commit/?id=51e23b9c9d9674a78dc97c5848c9efb4461e074d

> + memset(&args, 0, sizeof(args));
> + args.dp = ip;
> + args.name = attrip->attri_name;
> + args.namelen = attrp->alfi_name_len;
> + args.attr_filter = attrp->alfi_attr_flags;
> + if (attrp->alfi_op_flags == XFS_ATTR_OP_FLAGS_SET) {
> + args.value = attrip->attri_value;
> + args.valuelen = attrp->alfi_value_len;
> + }
> +
> + error = xfs_attr_set(&args);

Er...

> +
> + xfs_attri_release(attrip);

The transaction commit will take care of releasing attrip.

> + xfs_irele(ip);
> + return error;
> +}
> +
> +static const struct xfs_item_ops xfs_attri_item_ops = {
> + .iop_size = xfs_attri_item_size,
> + .iop_format = xfs_attri_item_format,
> + .iop_unpin = xfs_attri_item_unpin,
> + .iop_committed = xfs_attri_item_committed,
> + .iop_committing = xfs_attri_item_committing,
> + .iop_release = xfs_attri_item_release,
> + .iop_recover = xfs_attri_item_recover,
> + .iop_match = xfs_attri_item_match,

This needs an ->iop_relog method so that we can relog the attri log item
if the log starts to fill up.

> +};
> +
> +
> +
> +STATIC int
> +xlog_recover_attri_commit_pass2(
> + struct xlog *log,
> + struct list_head *buffer_list,
> + struct xlog_recover_item *item,
> + xfs_lsn_t lsn)
> +{
> + int error;
> + struct xfs_mount *mp = log->l_mp;
> + struct xfs_attri_log_item *attrip;
> + struct xfs_attri_log_format *attri_formatp;
> + char *name = NULL;
> + char *value = NULL;
> + int region = 0;
> +
> + attri_formatp = item->ri_buf[region].i_addr;

Please check the __pad field for zeroes here.

> + attrip = xfs_attri_init(mp);
> + error = xfs_attri_copy_format(&item->ri_buf[region],
> + &attrip->attri_format);
> + if (error) {
> + xfs_attri_item_free(attrip);
> + return error;
> + }
> +
> + attrip->attri_name_len = attri_formatp->alfi_name_len;
> + attrip->attri_value_len = attri_formatp->alfi_value_len;
> + attrip = krealloc(attrip, sizeof(struct xfs_attri_log_item) +
> + attrip->attri_name_len + attrip->attri_value_len,
> + GFP_NOFS | __GFP_NOFAIL);
> +
> + ASSERT(attrip->attri_name_len > 0);

If attri_name_len is zero, reject the whole thing with EFSCORRUPTED.

> + region++;
> + name = ((char *)attrip) + sizeof(struct xfs_attri_log_item);
> + memcpy(name, item->ri_buf[region].i_addr,
> + attrip->attri_name_len);
> + attrip->attri_name = name;
> +
> + if (attrip->attri_value_len > 0) {
> + region++;
> + value = ((char *)attrip) + sizeof(struct xfs_attri_log_item) +
> + attrip->attri_name_len;
> + memcpy(value, item->ri_buf[region].i_addr,
> + attrip->attri_value_len);
> + attrip->attri_value = value;
> + }

Question: is it valid for an attri item to have value_len > 0 for an
XFS_ATTRI_OP_FLAGS_REMOVE operation?

Granted, that level of validation might be better left to the _recover
function.

> +
> + /*
> + * The ATTRI has two references. One for the ATTRD and one for ATTRI to
> + * ensure it makes it into the AIL. Insert the ATTRI into the AIL
> + * directly and drop the ATTRI reference. Note that
> + * xfs_trans_ail_update() drops the AIL lock.
> + */
> + xfs_trans_ail_insert(log->l_ailp, &attrip->attri_item, lsn);
> + xfs_attri_release(attrip);
> + return 0;
> +}
> +
> +const struct xlog_recover_item_ops xlog_attri_item_ops = {
> + .item_type = XFS_LI_ATTRI,
> + .commit_pass2 = xlog_recover_attri_commit_pass2,
> +};
> +
> +/*
> + * This routine is called when an ATTRD format structure is found in a committed
> + * transaction in the log. Its purpose is to cancel the corresponding ATTRI if
> + * it was still in the log. To do this it searches the AIL for the ATTRI with
> + * an id equal to that in the ATTRD format structure. If we find it we drop
> + * the ATTRD reference, which removes the ATTRI from the AIL and frees it.
> + */
> +STATIC int
> +xlog_recover_attrd_commit_pass2(
> + struct xlog *log,
> + struct list_head *buffer_list,
> + struct xlog_recover_item *item,
> + xfs_lsn_t lsn)
> +{
> + struct xfs_attrd_log_format *attrd_formatp;
> +
> + attrd_formatp = item->ri_buf[0].i_addr;
> + ASSERT((item->ri_buf[0].i_len ==
> + (sizeof(struct xfs_attrd_log_format))));
> +
> + xlog_recover_release_intent(log, XFS_LI_ATTRI,
> + attrd_formatp->alfd_alf_id);
> + return 0;
> +}
> +
> +const struct xlog_recover_item_ops xlog_attrd_item_ops = {
> + .item_type = XFS_LI_ATTRD,
> + .commit_pass2 = xlog_recover_attrd_commit_pass2,
> +};
> diff --git a/fs/xfs/xfs_attr_item.h b/fs/xfs/xfs_attr_item.h
> new file mode 100644
> index 0000000..7dd2572
> --- /dev/null
> +++ b/fs/xfs/xfs_attr_item.h
> @@ -0,0 +1,76 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * Copyright (C) 2019 Oracle. All Rights Reserved.
> + * Author: Allison Collins <allison.henderson@oracle.com>
> + */
> +#ifndef __XFS_ATTR_ITEM_H__
> +#define __XFS_ATTR_ITEM_H__
> +
> +/* kernel only ATTRI/ATTRD definitions */
> +
> +struct xfs_mount;
> +struct kmem_zone;
> +
> +/*
> + * Define ATTR flag bits. Manipulated by set/clear/test_bit operators.
> + */
> +#define XFS_ATTRI_RECOVERED 1
> +
> +
> +/* iovec length must be 32-bit aligned */
> +#define ATTR_NVEC_SIZE(size) (size == sizeof(int32_t) ? sizeof(int32_t) : \
> + size + sizeof(int32_t) - \
> + (size % sizeof(int32_t)))

Can you turn this into a static inline helper?

And use one of the roundup() variants to ensure the proper alignment
instead of this open-coded stuff? :)

> +
> +/*
> + * This is the "attr intention" log item. It is used to log the fact that some
> + * attribute operations need to be processed. An operation is currently either
> + * a set or remove. Set or remove operations are described by the xfs_attr_item
> + * which may be logged to this intent. Intents are used in conjunction with the
> + * "attr done" log item described below.
> + *
> + * The ATTRI is reference counted so that it is not freed prior to both the
> + * ATTRI and ATTRD being committed and unpinned. This ensures the ATTRI is
> + * inserted into the AIL even in the event of out of order ATTRI/ATTRD
> + * processing. In other words, an ATTRI is born with two references:
> + *
> + * 1.) an ATTRI held reference to track ATTRI AIL insertion
> + * 2.) an ATTRD held reference to track ATTRD commit
> + *
> + * On allocation, both references are the responsibility of the caller. Once the
> + * ATTRI is added to and dirtied in a transaction, ownership of reference one
> + * transfers to the transaction. The reference is dropped once the ATTRI is
> + * inserted to the AIL or in the event of failure along the way (e.g., commit
> + * failure, log I/O error, etc.). Note that the caller remains responsible for
> + * the ATTRD reference under all circumstances to this point. The caller has no
> + * means to detect failure once the transaction is committed, however.
> + * Therefore, an ATTRD is required after this point, even in the event of
> + * unrelated failure.
> + *
> + * Once an ATTRD is allocated and dirtied in a transaction, reference two
> + * transfers to the transaction. The ATTRD reference is dropped once it reaches
> + * the unpin handler. Similar to the ATTRI, the reference also drops in the
> + * event of commit failure or log I/O errors. Note that the ATTRD is not
> + * inserted in the AIL, so at this point both the ATTRI and ATTRD are freed.

I don't think it's necessary to document the entire log intent/log done
refcount state machine here; it'll do to record just the bits that are
specific to delayed xattr operations.

> + */
> +struct xfs_attri_log_item {
> + struct xfs_log_item attri_item;
> + atomic_t attri_refcount;
> + int attri_name_len;
> + void *attri_name;
> + int attri_value_len;
> + void *attri_value;

Please compress this structure a bit by moving the two pointers to be
adjacent instead of interspersed with ints.

Ok, now on to digesting the new state machine...

--D

> + struct xfs_attri_log_format attri_format;
> +};
> +
> +/*
> + * This is the "attr done" log item. It is used to log the fact that some attrs
> + * earlier mentioned in an attri item have been freed.
> + */
> +struct xfs_attrd_log_item {
> + struct xfs_attri_log_item *attrd_attrip;
> + struct xfs_log_item attrd_item;
> + struct xfs_attrd_log_format attrd_format;
> +};
> +
> +#endif /* __XFS_ATTR_ITEM_H__ */
> diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c
> index 8f8837f..d7787a5 100644
> --- a/fs/xfs/xfs_attr_list.c
> +++ b/fs/xfs/xfs_attr_list.c
> @@ -15,6 +15,7 @@
> #include "xfs_inode.h"
> #include "xfs_trans.h"
> #include "xfs_bmap.h"
> +#include "xfs_da_btree.h"
> #include "xfs_attr.h"
> #include "xfs_attr_sf.h"
> #include "xfs_attr_leaf.h"
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 3fbd98f..d5d1959 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 c1771e7..62e1534 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 5e16545..5ecc76c 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_log.c b/fs/xfs/xfs_log.c
> index fa2d05e..3457f22 100644
> --- a/fs/xfs/xfs_log.c
> +++ b/fs/xfs/xfs_log.c
> @@ -1993,6 +1993,10 @@ xlog_print_tic_res(
> REG_TYPE_STR(CUD_FORMAT, "cud_format"),
> REG_TYPE_STR(BUI_FORMAT, "bui_format"),
> REG_TYPE_STR(BUD_FORMAT, "bud_format"),
> + REG_TYPE_STR(ATTRI_FORMAT, "attri_format"),
> + REG_TYPE_STR(ATTRD_FORMAT, "attrd_format"),
> + REG_TYPE_STR(ATTR_NAME, "attr_name"),
> + REG_TYPE_STR(ATTR_VALUE, "attr_value"),
> };
> BUILD_BUG_ON(ARRAY_SIZE(res_type_str) != XLOG_REG_TYPE_MAX + 1);
> #undef REG_TYPE_STR
> diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
> index a8289ad..cb951cd 100644
> --- a/fs/xfs/xfs_log_recover.c
> +++ b/fs/xfs/xfs_log_recover.c
> @@ -1775,6 +1775,8 @@ static const struct xlog_recover_item_ops *xlog_recover_item_ops[] = {
> &xlog_cud_item_ops,
> &xlog_bui_item_ops,
> &xlog_bud_item_ops,
> + &xlog_attri_item_ops,
> + &xlog_attrd_item_ops,
> };
>
> static const struct xlog_recover_item_ops *
> diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h
> index 0aa87c2..bc9c25e 100644
> --- a/fs/xfs/xfs_ondisk.h
> +++ b/fs/xfs/xfs_ondisk.h
> @@ -132,6 +132,8 @@ xfs_check_ondisk_structs(void)
> XFS_CHECK_STRUCT_SIZE(struct xfs_inode_log_format, 56);
> XFS_CHECK_STRUCT_SIZE(struct xfs_qoff_logformat, 20);
> XFS_CHECK_STRUCT_SIZE(struct xfs_trans_header, 16);
> + XFS_CHECK_STRUCT_SIZE(struct xfs_attri_log_format, 40);
> + XFS_CHECK_STRUCT_SIZE(struct xfs_attrd_log_format, 16);
>
> /*
> * The v5 superblock format extended several v4 header structures with
> diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
> index bca48b3..9b0c790 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 "xfs_acl.h"
> #include "xfs_da_btree.h"
> --
> 2.7.4
>