Re: [PATCH 04/17] xfs: rework deferred attribute operation setup

Alli
2022-05-06T23:44:01Z

On Fri, 2022-05-06 at 19:45 +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@redhat.com>
>
> Logged attribute intents only have set and remove types - there is
> no type of the replace operation. We should ahve a separate type for
> a replace operation, as it needs to perform operations that neither
> SET or REMOVE can perform.
>
> Add this type to the intent items and rearrange the deferred
> operation setup to reflect the different operations we are
> performing.
>
> Signed-off-by: Dave Chinner <dchinner@redhat.com>
Ok, makes sense
Reviewed-by: Allison Henderson<allison.henderson@oracle.com>

> ---
> fs/xfs/libxfs/xfs_attr.c | 165 +++++++++++++++++++----------
> ----
> fs/xfs/libxfs/xfs_attr.h | 2 -
> fs/xfs/libxfs/xfs_log_format.h | 1 +
> fs/xfs/xfs_attr_item.c | 9 +-
> fs/xfs/xfs_trace.h | 4 +
> 5 files changed, 110 insertions(+), 71 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index a4b0b20a3bab..817e15740f9c 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -671,6 +671,81 @@ xfs_attr_lookup(
> return xfs_attr_node_hasname(args, NULL);
> }
>
> +static int
> +xfs_attr_item_init(
> + struct xfs_da_args *args,
> + unsigned int op_flags, /* op flag (set or
> remove) */
> + struct xfs_attr_item **attr) /* new xfs_attr_item
> */
> +{
> +
> + struct xfs_attr_item *new;
> +
> + new = kmem_zalloc(sizeof(struct xfs_attr_item), KM_NOFS);
> + new->xattri_op_flags = op_flags;
> + new->xattri_da_args = args;
> +
> + *attr = new;
> + return 0;
> +}
> +
> +/* Sets an attribute for an inode as a deferred operation */
> +static int
> +xfs_attr_defer_add(
> + struct xfs_da_args *args)
> +{
> + struct xfs_attr_item *new;
> + int error = 0;
> +
> + error = xfs_attr_item_init(args, XFS_ATTR_OP_FLAGS_SET, &new);
> + if (error)
> + return error;
> +
> + new->xattri_dela_state = XFS_DAS_UNINIT;
> + xfs_defer_add(args->trans, XFS_DEFER_OPS_TYPE_ATTR, &new-
> >xattri_list);
> + trace_xfs_attr_defer_add(new->xattri_dela_state, args->dp);
> +
> + return 0;
> +}
> +
> +/* Sets an attribute for an inode as a deferred operation */
> +static int
> +xfs_attr_defer_replace(
> + struct xfs_da_args *args)
> +{
> + struct xfs_attr_item *new;
> + int error = 0;
> +
> + error = xfs_attr_item_init(args, XFS_ATTR_OP_FLAGS_REPLACE,
> &new);
> + if (error)
> + return error;
> +
> + new->xattri_dela_state = XFS_DAS_UNINIT;
> + xfs_defer_add(args->trans, XFS_DEFER_OPS_TYPE_ATTR, &new-
> >xattri_list);
> + trace_xfs_attr_defer_replace(new->xattri_dela_state, args->dp);
> +
> + return 0;
> +}
> +
> +/* Removes an attribute for an inode as a deferred operation */
> +static int
> +xfs_attr_defer_remove(
> + struct xfs_da_args *args)
> +{
> +
> + struct xfs_attr_item *new;
> + int error;
> +
> + error = xfs_attr_item_init(args, XFS_ATTR_OP_FLAGS_REMOVE,
> &new);
> + if (error)
> + return error;
> +
> + new->xattri_dela_state = XFS_DAS_UNINIT;
> + xfs_defer_add(args->trans, XFS_DEFER_OPS_TYPE_ATTR, &new-
> >xattri_list);
> + trace_xfs_attr_defer_remove(new->xattri_dela_state, args->dp);
> +
> + return 0;
> +}
> +
> /*
> * Note: If args->value is NULL the attribute will be removed, just
> like the
> * Linux ->setattr API.
> @@ -759,29 +834,35 @@ xfs_attr_set(
> }
>
> error = xfs_attr_lookup(args);
> - if (args->value) {
> - if (error == -EEXIST && (args->attr_flags &
> XATTR_CREATE))
> - goto out_trans_cancel;
> - if (error == -ENOATTR && (args->attr_flags &
> XATTR_REPLACE))
> - goto out_trans_cancel;
> - if (error != -ENOATTR && error != -EEXIST)
> + switch (error) {
> + case -EEXIST:
> + /* if no value, we are performing a remove operation */
> + if (!args->value) {
> + error = xfs_attr_defer_remove(args);
> + break;
> + }
> + /* Pure create fails if the attr already exists */
> + if (args->attr_flags & XATTR_CREATE)
> goto out_trans_cancel;
>
> - error = xfs_attr_set_deferred(args);
> - if (error)
> + error = xfs_attr_defer_replace(args);
> + break;
> + case -ENOATTR:
> + /* Can't remove what isn't there. */
> + if (!args->value)
> goto out_trans_cancel;
>
> - /* shortform attribute has already been committed */
> - if (!args->trans)
> - goto out_unlock;
> - } else {
> - if (error != -EEXIST)
> + /* Pure replace fails if no existing attr to replace.
> */
> + if (args->attr_flags & XATTR_REPLACE)
> goto out_trans_cancel;
>
> - error = xfs_attr_remove_deferred(args);
> - if (error)
> - goto out_trans_cancel;
> + error = xfs_attr_defer_add(args);
> + break;
> + default:
> + goto out_trans_cancel;
> }
> + if (error)
> + goto out_trans_cancel;
>
> /*
> * If this is a synchronous mount, make sure that the
> @@ -845,58 +926,6 @@ xfs_attrd_destroy_cache(void)
> xfs_attrd_cache = NULL;
> }
>
> -STATIC int
> -xfs_attr_item_init(
> - struct xfs_da_args *args,
> - unsigned int op_flags, /* op flag (set or
> remove) */
> - struct xfs_attr_item **attr) /* new xfs_attr_item
> */
> -{
> -
> - struct xfs_attr_item *new;
> -
> - new = kmem_zalloc(sizeof(struct xfs_attr_item), KM_NOFS);
> - new->xattri_op_flags = op_flags;
> - new->xattri_da_args = args;
> -
> - *attr = new;
> - return 0;
> -}
> -
> -/* Sets an attribute for an inode as a deferred operation */
> -int
> -xfs_attr_set_deferred(
> - struct xfs_da_args *args)
> -{
> - struct xfs_attr_item *new;
> - int error = 0;
> -
> - error = xfs_attr_item_init(args, XFS_ATTR_OP_FLAGS_SET, &new);
> - if (error)
> - return error;
> -
> - xfs_defer_add(args->trans, XFS_DEFER_OPS_TYPE_ATTR, &new-
> >xattri_list);
> -
> - return 0;
> -}
> -
> -/* Removes an attribute for an inode as a deferred operation */
> -int
> -xfs_attr_remove_deferred(
> - struct xfs_da_args *args)
> -{
> -
> - struct xfs_attr_item *new;
> - int error;
> -
> - error = xfs_attr_item_init(args, XFS_ATTR_OP_FLAGS_REMOVE,
> &new);
> - if (error)
> - return error;
> -
> - xfs_defer_add(args->trans, XFS_DEFER_OPS_TYPE_ATTR, &new-
> >xattri_list);
> -
> - return 0;
> -}
> -
> /*==================================================================
> ======
> * External routines when attribute list is inside the inode
>
> *====================================================================
> ====*/
> diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
> index f6c13d2bfbcd..c9c867e3406c 100644
> --- a/fs/xfs/libxfs/xfs_attr.h
> +++ b/fs/xfs/libxfs/xfs_attr.h
> @@ -521,8 +521,6 @@ bool xfs_attr_namecheck(const void *name, size_t
> length);
> int xfs_attr_calc_size(struct xfs_da_args *args, int *local);
> void xfs_init_attr_trans(struct xfs_da_args *args, struct
> xfs_trans_res *tres,
> unsigned int *total);
> -int xfs_attr_set_deferred(struct xfs_da_args *args);
> -int xfs_attr_remove_deferred(struct xfs_da_args *args);
>
> extern struct kmem_cache *xfs_attri_cache;
> extern struct kmem_cache *xfs_attrd_cache;
> diff --git a/fs/xfs/libxfs/xfs_log_format.h
> b/fs/xfs/libxfs/xfs_log_format.h
> index a27492e99673..f7edd1ecf6d9 100644
> --- a/fs/xfs/libxfs/xfs_log_format.h
> +++ b/fs/xfs/libxfs/xfs_log_format.h
> @@ -908,6 +908,7 @@ struct xfs_icreate_log {
> */
> #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_REPLACE 3 /* Replace the attribute */
> #define XFS_ATTR_OP_FLAGS_TYPE_MASK 0xFF /* Flags type mask */
>
> /*
> diff --git a/fs/xfs/xfs_attr_item.c b/fs/xfs/xfs_attr_item.c
> index 5f8680b05079..fe1e37696634 100644
> --- a/fs/xfs/xfs_attr_item.c
> +++ b/fs/xfs/xfs_attr_item.c
> @@ -311,6 +311,7 @@ xfs_xattri_finish_update(
>
> switch (op) {
> case XFS_ATTR_OP_FLAGS_SET:
> + case XFS_ATTR_OP_FLAGS_REPLACE:
> error = xfs_attr_set_iter(attr);
> break;
> case XFS_ATTR_OP_FLAGS_REMOVE:
> @@ -500,8 +501,14 @@ xfs_attri_validate(
> return false;
>
> /* alfi_op_flags should be either a set or remove */
> - if (op != XFS_ATTR_OP_FLAGS_SET && op !=
> XFS_ATTR_OP_FLAGS_REMOVE)
> + switch (op) {
> + case XFS_ATTR_OP_FLAGS_SET:
> + case XFS_ATTR_OP_FLAGS_REPLACE:
> + case XFS_ATTR_OP_FLAGS_REMOVE:
> + break;
> + default:
> return false;
> + }
>
> if (attrp->alfi_value_len > XATTR_SIZE_MAX)
> return false;
> diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
> index fec4198b738b..01ce0401aa32 100644
> --- a/fs/xfs/xfs_trace.h
> +++ b/fs/xfs/xfs_trace.h
> @@ -4154,6 +4154,10 @@
> DEFINE_DAS_STATE_EVENT(xfs_attr_leaf_addname_return);
> DEFINE_DAS_STATE_EVENT(xfs_attr_node_addname_return);
> DEFINE_DAS_STATE_EVENT(xfs_attr_remove_iter_return);
> DEFINE_DAS_STATE_EVENT(xfs_attr_rmtval_remove_return);
> +DEFINE_DAS_STATE_EVENT(xfs_attr_defer_add);
> +DEFINE_DAS_STATE_EVENT(xfs_attr_defer_replace);
> +DEFINE_DAS_STATE_EVENT(xfs_attr_defer_remove);
> +
>
> TRACE_EVENT(xfs_force_shutdown,
> TP_PROTO(struct xfs_mount *mp, int ptag, int flags, const char
> *fname,