// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2022 Oracle.  All Rights Reserved.
 * Author: Allison Henderson <allison.henderson@oracle.com>
 */

#include "xfs_platform.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_trans_resv.h"
#include "xfs_shared.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_log_format.h"
#include "xfs_trans.h"
#include "xfs_bmap_btree.h"
#include "xfs_trans_priv.h"
#include "xfs_log.h"
#include "xfs_inode.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
#include "xfs_attr.h"
#include "xfs_attr_item.h"
#include "xfs_trace.h"
#include "xfs_trans_space.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_log_priv.h"
#include "xfs_log_recover.h"
#include "xfs_parent.h"

struct kmem_cache               *xfs_attri_cache;
struct kmem_cache               *xfs_attrd_cache;

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);
}

/*
 * Shared xattr name/value buffers for logged extended attribute operations
 *
 * When logging updates to extended attributes, we can create quite a few
 * attribute log intent items for a single xattr update.  To avoid cycling the
 * memory allocator and memcpy overhead, the name (and value, for setxattr)
 * are kept in a refcounted object that is shared across all related log items
 * and the upper-level deferred work state structure.  The shared buffer has
 * a control structure, followed by the name, and then the value.
 */

static inline struct xfs_attri_log_nameval *
xfs_attri_log_nameval_get(
        struct xfs_attri_log_nameval    *nv)
{
        if (!refcount_inc_not_zero(&nv->refcount))
                return NULL;
        return nv;
}

static inline void
xfs_attri_log_nameval_put(
        struct xfs_attri_log_nameval    *nv)
{
        if (!nv)
                return;
        if (refcount_dec_and_test(&nv->refcount))
                kvfree(nv);
}

static inline struct xfs_attri_log_nameval *
xfs_attri_log_nameval_alloc(
        const void                      *name,
        unsigned int                    name_len,
        const void                      *new_name,
        unsigned int                    new_name_len,
        const void                      *value,
        unsigned int                    value_len,
        const void                      *new_value,
        unsigned int                    new_value_len)
{
        struct xfs_attri_log_nameval    *nv;

        /*
         * This could be over 64kB in length, so we have to use kvmalloc() for
         * this. But kvmalloc() utterly sucks, so we use our own version.
         */
        nv = xlog_kvmalloc(sizeof(struct xfs_attri_log_nameval) +
                                        name_len + new_name_len + value_len +
                                        new_value_len);

        nv->name.iov_base = nv + 1;
        nv->name.iov_len = name_len;
        memcpy(nv->name.iov_base, name, name_len);

        if (new_name_len) {
                nv->new_name.iov_base = nv->name.iov_base + name_len;
                nv->new_name.iov_len = new_name_len;
                memcpy(nv->new_name.iov_base, new_name, new_name_len);
        } else {
                nv->new_name.iov_base = NULL;
                nv->new_name.iov_len = 0;
        }

        if (value_len) {
                nv->value.iov_base = nv->name.iov_base + name_len + new_name_len;
                nv->value.iov_len = value_len;
                memcpy(nv->value.iov_base, value, value_len);
        } else {
                nv->value.iov_base = NULL;
                nv->value.iov_len = 0;
        }

        if (new_value_len) {
                nv->new_value.iov_base = nv->name.iov_base + name_len +
                                                new_name_len + value_len;
                nv->new_value.iov_len = new_value_len;
                memcpy(nv->new_value.iov_base, new_value, new_value_len);
        } else {
                nv->new_value.iov_base = NULL;
                nv->new_value.iov_len = 0;
        }

        refcount_set(&nv->refcount, 1);
        return nv;
}

STATIC void
xfs_attri_item_free(
        struct xfs_attri_log_item       *attrip)
{
        kvfree(attrip->attri_item.li_lv_shadow);
        xfs_attri_log_nameval_put(attrip->attri_nameval);
        kmem_cache_free(xfs_attri_cache, 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))
                return;

        xfs_trans_ail_delete(&attrip->attri_item, 0);
        xfs_attri_item_free(attrip);
}

STATIC void
xfs_attri_item_size(
        struct xfs_log_item             *lip,
        int                             *nvecs,
        int                             *nbytes)
{
        struct xfs_attri_log_item       *attrip = ATTRI_ITEM(lip);
        struct xfs_attri_log_nameval    *nv = attrip->attri_nameval;

        *nvecs += 2;
        *nbytes += sizeof(struct xfs_attri_log_format) +
                        xlog_calc_iovec_len(nv->name.iov_len);

        if (nv->new_name.iov_len) {
                *nvecs += 1;
                *nbytes += xlog_calc_iovec_len(nv->new_name.iov_len);
        }

        if (nv->value.iov_len) {
                *nvecs += 1;
                *nbytes += xlog_calc_iovec_len(nv->value.iov_len);
        }

        if (nv->new_value.iov_len) {
                *nvecs += 1;
                *nbytes += xlog_calc_iovec_len(nv->new_value.iov_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 xlog_format_buf          *lfb)
{
        struct xfs_attri_log_item       *attrip = ATTRI_ITEM(lip);
        struct xfs_attri_log_nameval    *nv = attrip->attri_nameval;

        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(nv->name.iov_len > 0);
        attrip->attri_format.alfi_size++;

        if (nv->new_name.iov_len > 0)
                attrip->attri_format.alfi_size++;

        if (nv->value.iov_len > 0)
                attrip->attri_format.alfi_size++;

        if (nv->new_value.iov_len > 0)
                attrip->attri_format.alfi_size++;

        xlog_format_copy(lfb, XLOG_REG_TYPE_ATTRI_FORMAT, &attrip->attri_format,
                        sizeof(struct xfs_attri_log_format));

        xlog_format_copy(lfb, XLOG_REG_TYPE_ATTR_NAME, nv->name.iov_base,
                        nv->name.iov_len);

        if (nv->new_name.iov_len > 0)
                xlog_format_copy(lfb, XLOG_REG_TYPE_ATTR_NEWNAME,
                                nv->new_name.iov_base, nv->new_name.iov_len);

        if (nv->value.iov_len > 0)
                xlog_format_copy(lfb, XLOG_REG_TYPE_ATTR_VALUE,
                                nv->value.iov_base, nv->value.iov_len);

        if (nv->new_value.iov_len > 0)
                xlog_format_copy(lfb, XLOG_REG_TYPE_ATTR_NEWVALUE,
                                nv->new_value.iov_base, nv->new_value.iov_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)
{
        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.  Caller may allocate an additional
 * trailing buffer for name and value
 */
STATIC struct xfs_attri_log_item *
xfs_attri_init(
        struct xfs_mount                *mp,
        struct xfs_attri_log_nameval    *nv)
{
        struct xfs_attri_log_item       *attrip;

        attrip = kmem_cache_zalloc(xfs_attri_cache, GFP_KERNEL | __GFP_NOFAIL);

        /*
         * Grab an extra reference to the name/value buffer for this log item.
         * The caller retains its own reference!
         */
        attrip->attri_nameval = xfs_attri_log_nameval_get(nv);
        ASSERT(attrip->attri_nameval);

        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;
}

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)
{
        kvfree(attrdp->attrd_item.li_lv_shadow);
        kmem_cache_free(xfs_attrd_cache, attrdp);
}

STATIC void
xfs_attrd_item_size(
        struct xfs_log_item             *lip,
        int                             *nvecs,
        int                             *nbytes)
{
        *nvecs += 1;
        *nbytes += sizeof(struct xfs_attrd_log_format);
}

/*
 * 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 xlog_format_buf          *lfb)
{
        struct xfs_attrd_log_item       *attrdp = ATTRD_ITEM(lip);

        attrdp->attrd_format.alfd_type = XFS_LI_ATTRD;
        attrdp->attrd_format.alfd_size = 1;

        xlog_format_copy(lfb, XLOG_REG_TYPE_ATTRD_FORMAT,
                        &attrdp->attrd_format,
                        sizeof(struct xfs_attrd_log_format));
}

/*
 * The ATTRD is either committed or aborted if the transaction is canceled. If
 * the transaction is canceled, 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);
        xfs_attrd_item_free(attrdp);
}

static struct xfs_log_item *
xfs_attrd_item_intent(
        struct xfs_log_item     *lip)
{
        return &ATTRD_ITEM(lip)->attrd_attrip->attri_item;
}

static inline unsigned int
xfs_attr_log_item_op(const struct xfs_attri_log_format *attrp)
{
        return attrp->alfi_op_flags & XFS_ATTRI_OP_FLAGS_TYPE_MASK;
}

/* Log an attr to the intent item. */
STATIC void
xfs_attr_log_item(
        struct xfs_trans                *tp,
        struct xfs_attri_log_item       *attrip,
        const struct xfs_attr_intent    *attr)
{
        struct xfs_attri_log_format     *attrp;
        struct xfs_attri_log_nameval    *nv = attr->xattri_nameval;
        struct xfs_da_args              *args = attr->xattri_da_args;

        /*
         * At this point the xfs_attr_intent 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_intent
         */
        attrp = &attrip->attri_format;
        attrp->alfi_ino = args->dp->i_ino;
        ASSERT(!(attr->xattri_op_flags & ~XFS_ATTRI_OP_FLAGS_TYPE_MASK));
        attrp->alfi_op_flags = attr->xattri_op_flags;
        attrp->alfi_value_len = nv->value.iov_len;

        switch (xfs_attr_log_item_op(attrp)) {
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
                ASSERT(nv->value.iov_len == nv->new_value.iov_len);

                attrp->alfi_igen = VFS_I(args->dp)->i_generation;
                attrp->alfi_old_name_len = nv->name.iov_len;
                attrp->alfi_new_name_len = nv->new_name.iov_len;
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
                attrp->alfi_igen = VFS_I(args->dp)->i_generation;
                fallthrough;
        default:
                attrp->alfi_name_len = nv->name.iov_len;
                break;
        }

        ASSERT(!(args->attr_filter & ~XFS_ATTRI_FILTER_MASK));
        attrp->alfi_attr_filter = args->attr_filter;
}

/* 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_intent          *attr;
        struct xfs_da_args              *args;

        ASSERT(count == 1);

        /*
         * Each attr item only performs one attribute operation at a time, so
         * this is a list of one
         */
        attr = list_first_entry_or_null(items, struct xfs_attr_intent,
                        xattri_list);
        args = attr->xattri_da_args;

        if (!(args->op_flags & XFS_DA_OP_LOGGED))
                return NULL;

        /*
         * Create a buffer to store the attribute name and value.  This buffer
         * will be shared between the higher level deferred xattr work state
         * and the lower level xattr log items.
         */
        if (!attr->xattri_nameval) {
                /*
                 * Transfer our reference to the name/value buffer to the
                 * deferred work state structure.
                 */
                attr->xattri_nameval = xfs_attri_log_nameval_alloc(
                                args->name, args->namelen,
                                args->new_name, args->new_namelen,
                                args->value, args->valuelen,
                                args->new_value, args->new_valuelen);
        }

        attrip = xfs_attri_init(mp, attr->xattri_nameval);
        xfs_attr_log_item(tp, attrip, attr);

        return &attrip->attri_item;
}

static inline void
xfs_attr_free_item(
        struct xfs_attr_intent          *attr)
{
        if (attr->xattri_da_state)
                xfs_da_state_free(attr->xattri_da_state);
        xfs_attri_log_nameval_put(attr->xattri_nameval);
        if (attr->xattri_da_args->op_flags & XFS_DA_OP_RECOVERY)
                kfree(attr);
        else
                kmem_cache_free(xfs_attr_intent_cache, attr);
}

static inline struct xfs_attr_intent *attri_entry(const struct list_head *e)
{
        return list_entry(e, struct xfs_attr_intent, xattri_list);
}

/* 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_intent          *attr = attri_entry(item);
        struct xfs_da_args              *args;
        int                             error;

        args = attr->xattri_da_args;

        /* Reset trans after EAGAIN cycle since the transaction is new */
        args->trans = tp;

        if (XFS_TEST_ERROR(args->dp->i_mount, XFS_ERRTAG_LARP)) {
                error = -EIO;
                goto out;
        }

        /* If an attr removal is trivially complete, we're done. */
        if (attr->xattri_op_flags == XFS_ATTRI_OP_FLAGS_REMOVE &&
            !xfs_inode_hasattr(args->dp)) {
                error = 0;
                goto out;
        }

        error = xfs_attr_set_iter(attr);
        if (!error && attr->xattri_dela_state != XFS_DAS_DONE)
                return -EAGAIN;

out:
        xfs_attr_free_item(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_intent          *attr = attri_entry(item);

        xfs_attr_free_item(attr);
}

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;
}

static inline bool
xfs_attri_validate_namelen(unsigned int namelen)
{
        return namelen > 0 && namelen <= XATTR_NAME_MAX;
}

/* Is this recovered ATTRI format ok? */
static inline bool
xfs_attri_validate(
        struct xfs_mount                *mp,
        struct xfs_attri_log_format     *attrp)
{
        unsigned int                    op = xfs_attr_log_item_op(attrp);

        if (attrp->alfi_op_flags & ~XFS_ATTRI_OP_FLAGS_TYPE_MASK)
                return false;

        if (attrp->alfi_attr_filter & ~XFS_ATTRI_FILTER_MASK)
                return false;

        if (!xfs_attr_check_namespace(attrp->alfi_attr_filter &
                                      XFS_ATTR_NSP_ONDISK_MASK))
                return false;

        switch (op) {
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
                if (!xfs_has_parent(mp))
                        return false;
                if (attrp->alfi_value_len != sizeof(struct xfs_parent_rec))
                        return false;
                if (!xfs_attri_validate_namelen(attrp->alfi_name_len))
                        return false;
                if (!(attrp->alfi_attr_filter & XFS_ATTR_PARENT))
                        return false;
                break;
        case XFS_ATTRI_OP_FLAGS_SET:
        case XFS_ATTRI_OP_FLAGS_REPLACE:
                if (!xfs_is_using_logged_xattrs(mp))
                        return false;
                if (attrp->alfi_value_len > XATTR_SIZE_MAX)
                        return false;
                if (!xfs_attri_validate_namelen(attrp->alfi_name_len))
                        return false;
                break;
        case XFS_ATTRI_OP_FLAGS_REMOVE:
                if (!xfs_is_using_logged_xattrs(mp))
                        return false;
                if (attrp->alfi_value_len != 0)
                        return false;
                if (!xfs_attri_validate_namelen(attrp->alfi_name_len))
                        return false;
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
                if (!xfs_has_parent(mp))
                        return false;
                if (!xfs_attri_validate_namelen(attrp->alfi_old_name_len))
                        return false;
                if (!xfs_attri_validate_namelen(attrp->alfi_new_name_len))
                        return false;
                if (attrp->alfi_value_len != sizeof(struct xfs_parent_rec))
                        return false;
                if (!(attrp->alfi_attr_filter & XFS_ATTR_PARENT))
                        return false;
                break;
        default:
                return false;
        }

        return xfs_verify_ino(mp, attrp->alfi_ino);
}

static int
xfs_attri_iread_extents(
        struct xfs_inode                *ip)
{
        struct xfs_trans                *tp;
        int                             error;

        tp = xfs_trans_alloc_empty(ip->i_mount);
        xfs_ilock(ip, XFS_ILOCK_EXCL);
        error = xfs_iread_extents(tp, ip, XFS_ATTR_FORK);
        xfs_iunlock(ip, XFS_ILOCK_EXCL);
        xfs_trans_cancel(tp);

        return error;
}

static inline struct xfs_attr_intent *
xfs_attri_recover_work(
        struct xfs_mount                *mp,
        struct xfs_defer_pending        *dfp,
        struct xfs_attri_log_format     *attrp,
        struct xfs_inode                **ipp,
        struct xfs_attri_log_nameval    *nv)
{
        struct xfs_attr_intent          *attr;
        struct xfs_da_args              *args;
        struct xfs_inode                *ip;
        int                             local;
        int                             error;

        /*
         * Parent pointer attr items record the generation but regular logged
         * xattrs do not; select the right iget function.
         */
        switch (xfs_attr_log_item_op(attrp)) {
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
                error = xlog_recover_iget_handle(mp, attrp->alfi_ino,
                                attrp->alfi_igen, &ip);
                break;
        default:
                error = xlog_recover_iget(mp, attrp->alfi_ino, &ip);
                break;
        }
        if (error) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, attrp,
                                sizeof(*attrp));
                return ERR_PTR(-EFSCORRUPTED);
        }

        if (xfs_inode_has_attr_fork(ip)) {
                error = xfs_attri_iread_extents(ip);
                if (error) {
                        xfs_irele(ip);
                        return ERR_PTR(error);
                }
        }

        attr = kzalloc(sizeof(struct xfs_attr_intent) +
                        sizeof(struct xfs_da_args), GFP_KERNEL | __GFP_NOFAIL);
        args = (struct xfs_da_args *)(attr + 1);

        attr->xattri_da_args = args;
        attr->xattri_op_flags = xfs_attr_log_item_op(attrp);

        /*
         * We're reconstructing the deferred work state structure from the
         * recovered log item.  Grab a reference to the name/value buffer and
         * attach it to the new work state.
         */
        attr->xattri_nameval = xfs_attri_log_nameval_get(nv);
        ASSERT(attr->xattri_nameval);

        args->dp = ip;
        args->geo = mp->m_attr_geo;
        args->whichfork = XFS_ATTR_FORK;
        args->name = nv->name.iov_base;
        args->namelen = nv->name.iov_len;
        args->new_name = nv->new_name.iov_base;
        args->new_namelen = nv->new_name.iov_len;
        args->value = nv->value.iov_base;
        args->valuelen = nv->value.iov_len;
        args->new_value = nv->new_value.iov_base;
        args->new_valuelen = nv->new_value.iov_len;
        args->attr_filter = attrp->alfi_attr_filter & XFS_ATTRI_FILTER_MASK;
        args->op_flags = XFS_DA_OP_RECOVERY | XFS_DA_OP_OKNOENT |
                         XFS_DA_OP_LOGGED;
        args->owner = args->dp->i_ino;
        xfs_attr_sethash(args);

        switch (xfs_attr_intent_op(attr)) {
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
        case XFS_ATTRI_OP_FLAGS_SET:
        case XFS_ATTRI_OP_FLAGS_REPLACE:
                args->total = xfs_attr_calc_size(args, &local);
                if (xfs_inode_hasattr(args->dp))
                        attr->xattri_dela_state = xfs_attr_init_replace_state(args);
                else
                        attr->xattri_dela_state = xfs_attr_init_add_state(args);
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
        case XFS_ATTRI_OP_FLAGS_REMOVE:
                attr->xattri_dela_state = xfs_attr_init_remove_state(args);
                break;
        }

        xfs_defer_add_item(dfp, &attr->xattri_list);
        *ipp = ip;
        return attr;
}

/*
 * Process an attr intent item that was recovered from the log.  We need to
 * delete the attr that it describes.
 */
STATIC int
xfs_attr_recover_work(
        struct xfs_defer_pending        *dfp,
        struct list_head                *capture_list)
{
        struct xfs_log_item             *lip = dfp->dfp_intent;
        struct xfs_attri_log_item       *attrip = ATTRI_ITEM(lip);
        struct xfs_attr_intent          *attr;
        struct xfs_mount                *mp = lip->li_log->l_mp;
        struct xfs_inode                *ip = NULL;
        struct xfs_da_args              *args;
        struct xfs_trans                *tp;
        struct xfs_trans_res            resv;
        struct xfs_attri_log_format     *attrp;
        struct xfs_attri_log_nameval    *nv = attrip->attri_nameval;
        int                             error;
        unsigned int                    total = 0;

        /*
         * 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 (!xfs_attri_validate(mp, attrp) ||
            !xfs_attr_namecheck(attrp->alfi_attr_filter, nv->name.iov_base,
                                nv->name.iov_len))
                return -EFSCORRUPTED;

        attr = xfs_attri_recover_work(mp, dfp, attrp, &ip, nv);
        if (IS_ERR(attr))
                return PTR_ERR(attr);
        args = attr->xattri_da_args;

        switch (xfs_attr_intent_op(attr)) {
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
        case XFS_ATTRI_OP_FLAGS_SET:
        case XFS_ATTRI_OP_FLAGS_REPLACE:
                resv = xfs_attr_set_resv(args);
                total = args->total;
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
        case XFS_ATTRI_OP_FLAGS_REMOVE:
                resv = M_RES(mp)->tr_attrrm;
                total = XFS_ATTRRM_SPACE_RES(mp);
                break;
        }
        resv = xlog_recover_resv(&resv);
        error = xfs_trans_alloc(mp, &resv, total, 0, XFS_TRANS_RESERVE, &tp);
        if (error)
                return error;
        args->trans = tp;

        xfs_ilock(ip, XFS_ILOCK_EXCL);
        xfs_trans_ijoin(tp, ip, 0);

        error = xlog_recover_finish_intent(tp, dfp);
        if (error == -EFSCORRUPTED)
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                &attrip->attri_format,
                                sizeof(attrip->attri_format));
        if (error)
                goto out_cancel;

        error = xfs_defer_ops_capture_and_commit(tp, capture_list);
out_unlock:
        xfs_iunlock(ip, XFS_ILOCK_EXCL);
        xfs_irele(ip);
        return error;
out_cancel:
        xfs_trans_cancel(tp);
        goto out_unlock;
}

/* Re-log an intent item to push the log tail forward. */
static struct xfs_log_item *
xfs_attr_relog_intent(
        struct xfs_trans                *tp,
        struct xfs_log_item             *intent,
        struct xfs_log_item             *done_item)
{
        struct xfs_attri_log_item       *old_attrip;
        struct xfs_attri_log_item       *new_attrip;
        struct xfs_attri_log_format     *new_attrp;
        struct xfs_attri_log_format     *old_attrp;

        old_attrip = ATTRI_ITEM(intent);
        old_attrp = &old_attrip->attri_format;

        /*
         * Create a new log item that shares the same name/value buffer as the
         * old log item.
         */
        new_attrip = xfs_attri_init(tp->t_mountp, old_attrip->attri_nameval);
        new_attrp = &new_attrip->attri_format;

        new_attrp->alfi_ino = old_attrp->alfi_ino;
        new_attrp->alfi_igen = old_attrp->alfi_igen;
        new_attrp->alfi_op_flags = old_attrp->alfi_op_flags;
        new_attrp->alfi_value_len = old_attrp->alfi_value_len;

        switch (xfs_attr_log_item_op(old_attrp)) {
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
                new_attrp->alfi_new_name_len = old_attrp->alfi_new_name_len;
                new_attrp->alfi_old_name_len = old_attrp->alfi_old_name_len;
                break;
        default:
                new_attrp->alfi_name_len = old_attrp->alfi_name_len;
                break;
        }

        new_attrp->alfi_attr_filter = old_attrp->alfi_attr_filter;

        return &new_attrip->attri_item;
}

/* 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)
{
        struct xfs_attri_log_item       *attrip;
        struct xfs_attrd_log_item       *attrdp;

        attrip = ATTRI_ITEM(intent);

        attrdp = kmem_cache_zalloc(xfs_attrd_cache, GFP_KERNEL | __GFP_NOFAIL);

        xfs_log_item_init(tp->t_mountp, &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->attrd_item;
}

void
xfs_attr_defer_add(
        struct xfs_da_args      *args,
        enum xfs_attr_defer_op  op)
{
        struct xfs_attr_intent  *new;
        unsigned int            log_op = 0;
        bool                    is_pptr = args->attr_filter & XFS_ATTR_PARENT;

        if (is_pptr) {
                ASSERT(xfs_has_parent(args->dp->i_mount));
                ASSERT((args->attr_filter & ~XFS_ATTR_PARENT) == 0);
                ASSERT(args->op_flags & XFS_DA_OP_LOGGED);
                ASSERT(args->valuelen == sizeof(struct xfs_parent_rec));
        }

        new = kmem_cache_zalloc(xfs_attr_intent_cache,
                        GFP_NOFS | __GFP_NOFAIL);
        new->xattri_da_args = args;

        /* Compute log operation from the higher level op and namespace. */
        switch (op) {
        case XFS_ATTR_DEFER_SET:
                if (is_pptr)
                        log_op = XFS_ATTRI_OP_FLAGS_PPTR_SET;
                else
                        log_op = XFS_ATTRI_OP_FLAGS_SET;
                break;
        case XFS_ATTR_DEFER_REPLACE:
                if (is_pptr)
                        log_op = XFS_ATTRI_OP_FLAGS_PPTR_REPLACE;
                else
                        log_op = XFS_ATTRI_OP_FLAGS_REPLACE;
                break;
        case XFS_ATTR_DEFER_REMOVE:
                if (is_pptr)
                        log_op = XFS_ATTRI_OP_FLAGS_PPTR_REMOVE;
                else
                        log_op = XFS_ATTRI_OP_FLAGS_REMOVE;
                break;
        default:
                ASSERT(0);
                break;
        }
        new->xattri_op_flags = log_op;

        /* Set up initial attr operation state. */
        switch (log_op) {
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
        case XFS_ATTRI_OP_FLAGS_SET:
                new->xattri_dela_state = xfs_attr_init_add_state(args);
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
                ASSERT(args->new_valuelen == args->valuelen);
                new->xattri_dela_state = xfs_attr_init_replace_state(args);
                break;
        case XFS_ATTRI_OP_FLAGS_REPLACE:
                new->xattri_dela_state = xfs_attr_init_replace_state(args);
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
        case XFS_ATTRI_OP_FLAGS_REMOVE:
                new->xattri_dela_state = xfs_attr_init_remove_state(args);
                break;
        }

        xfs_defer_add(args->trans, &new->xattri_list, &xfs_attr_defer_type);
        trace_xfs_attr_defer_add(new->xattri_dela_state, args->dp);
}

const struct xfs_defer_op_type xfs_attr_defer_type = {
        .name           = "attr",
        .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,
        .recover_work   = xfs_attr_recover_work,
        .relog_intent   = xfs_attr_relog_intent,
};

static inline void *
xfs_attri_validate_name_iovec(
        struct xfs_mount                *mp,
        struct xfs_attri_log_format     *attri_formatp,
        const struct kvec               *iovec,
        unsigned int                    name_len)
{
        if (iovec->iov_len != xlog_calc_iovec_len(name_len)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, sizeof(*attri_formatp));
                return NULL;
        }

        if (!xfs_attr_namecheck(attri_formatp->alfi_attr_filter, iovec->iov_base,
                                name_len)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, sizeof(*attri_formatp));
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                iovec->iov_base, iovec->iov_len);
                return NULL;
        }

        return iovec->iov_base;
}

static inline void *
xfs_attri_validate_value_iovec(
        struct xfs_mount                *mp,
        struct xfs_attri_log_format     *attri_formatp,
        const struct kvec               *iovec,
        unsigned int                    value_len)
{
        if (iovec->iov_len != xlog_calc_iovec_len(value_len)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, sizeof(*attri_formatp));
                return NULL;
        }

        if ((attri_formatp->alfi_attr_filter & XFS_ATTR_PARENT) &&
            !xfs_parent_valuecheck(mp, iovec->iov_base, value_len)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, sizeof(*attri_formatp));
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                iovec->iov_base, iovec->iov_len);
                return NULL;
        }

        return iovec->iov_base;
}

STATIC int
xlog_recover_attri_commit_pass2(
        struct xlog                     *log,
        struct list_head                *buffer_list,
        struct xlog_recover_item        *item,
        xfs_lsn_t                       lsn)
{
        struct xfs_mount                *mp = log->l_mp;
        struct xfs_attri_log_item       *attrip;
        struct xfs_attri_log_format     *attri_formatp;
        struct xfs_attri_log_nameval    *nv;
        const void                      *attr_name;
        const void                      *attr_value = NULL;
        const void                      *attr_new_name = NULL;
        const void                      *attr_new_value = NULL;
        size_t                          len;
        unsigned int                    name_len = 0;
        unsigned int                    value_len = 0;
        unsigned int                    new_name_len = 0;
        unsigned int                    new_value_len = 0;
        unsigned int                    op, i = 0;

        /* Validate xfs_attri_log_format before the large memory allocation */
        len = sizeof(struct xfs_attri_log_format);
        if (item->ri_buf[i].iov_len != len) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                item->ri_buf[0].iov_base, item->ri_buf[0].iov_len);
                return -EFSCORRUPTED;
        }

        attri_formatp = item->ri_buf[i].iov_base;
        if (!xfs_attri_validate(mp, attri_formatp)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, len);
                return -EFSCORRUPTED;
        }

        /* Check the number of log iovecs makes sense for the op code. */
        op = xfs_attr_log_item_op(attri_formatp);
        switch (op) {
        case XFS_ATTRI_OP_FLAGS_PPTR_REMOVE:
        case XFS_ATTRI_OP_FLAGS_PPTR_SET:
                /* Log item, attr name, attr value */
                if (item->ri_total != 3) {
                        XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                             attri_formatp, len);
                        return -EFSCORRUPTED;
                }
                name_len = attri_formatp->alfi_name_len;
                value_len = attri_formatp->alfi_value_len;
                break;
        case XFS_ATTRI_OP_FLAGS_SET:
        case XFS_ATTRI_OP_FLAGS_REPLACE:
                /* Log item, attr name, optional attr value */
                if (item->ri_total != 2 + !!attri_formatp->alfi_value_len) {
                        XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                             attri_formatp, len);
                        return -EFSCORRUPTED;
                }
                name_len = attri_formatp->alfi_name_len;
                value_len = attri_formatp->alfi_value_len;
                break;
        case XFS_ATTRI_OP_FLAGS_REMOVE:
                /* Log item, attr name */
                if (item->ri_total != 2) {
                        XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                             attri_formatp, len);
                        return -EFSCORRUPTED;
                }
                name_len = attri_formatp->alfi_name_len;
                break;
        case XFS_ATTRI_OP_FLAGS_PPTR_REPLACE:
                /*
                 * Log item, attr name, new attr name, attr value, new attr
                 * value
                 */
                if (item->ri_total != 5) {
                        XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                             attri_formatp, len);
                        return -EFSCORRUPTED;
                }
                name_len = attri_formatp->alfi_old_name_len;
                new_name_len = attri_formatp->alfi_new_name_len;
                new_value_len = value_len = attri_formatp->alfi_value_len;
                break;
        default:
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                     attri_formatp, len);
                return -EFSCORRUPTED;
        }
        i++;

        /* Validate the attr name */
        attr_name = xfs_attri_validate_name_iovec(mp, attri_formatp,
                        &item->ri_buf[i], name_len);
        if (!attr_name)
                return -EFSCORRUPTED;
        i++;

        /* Validate the new attr name */
        if (new_name_len > 0) {
                attr_new_name = xfs_attri_validate_name_iovec(mp,
                                        attri_formatp, &item->ri_buf[i],
                                        new_name_len);
                if (!attr_new_name)
                        return -EFSCORRUPTED;
                i++;
        }

        /* Validate the attr value, if present */
        if (value_len != 0) {
                attr_value = xfs_attri_validate_value_iovec(mp, attri_formatp,
                                &item->ri_buf[i], value_len);
                if (!attr_value)
                        return -EFSCORRUPTED;
                i++;
        }

        /* Validate the new attr value, if present */
        if (new_value_len != 0) {
                attr_new_value = xfs_attri_validate_value_iovec(mp,
                                        attri_formatp, &item->ri_buf[i],
                                        new_value_len);
                if (!attr_new_value)
                        return -EFSCORRUPTED;
                i++;
        }

        /*
         * Make sure we got the correct number of buffers for the operation
         * that we just loaded.
         */
        if (i != item->ri_total) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
                                attri_formatp, len);
                return -EFSCORRUPTED;
        }

        /*
         * Memory alloc failure will cause replay to abort.  We attach the
         * name/value buffer to the recovered incore log item and drop our
         * reference.
         */
        nv = xfs_attri_log_nameval_alloc(attr_name, name_len,
                        attr_new_name, new_name_len,
                        attr_value, value_len,
                        attr_new_value, new_value_len);

        attrip = xfs_attri_init(mp, nv);
        memcpy(&attrip->attri_format, attri_formatp, len);

        xlog_recover_intent_item(log, &attrip->attri_item, lsn,
                        &xfs_attr_defer_type);
        xfs_attri_log_nameval_put(nv);
        return 0;
}

/*
 * 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].iov_base;
        if (item->ri_buf[0].iov_len != sizeof(struct xfs_attrd_log_format)) {
                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, log->l_mp,
                                item->ri_buf[0].iov_base, item->ri_buf[0].iov_len);
                return -EFSCORRUPTED;
        }

        xlog_recover_release_intent(log, XFS_LI_ATTRI,
                                    attrd_formatp->alfd_alf_id);
        return 0;
}

static const struct xfs_item_ops xfs_attri_item_ops = {
        .flags          = XFS_ITEM_INTENT,
        .iop_size       = xfs_attri_item_size,
        .iop_format     = xfs_attri_item_format,
        .iop_unpin      = xfs_attri_item_unpin,
        .iop_release    = xfs_attri_item_release,
        .iop_match      = xfs_attri_item_match,
};

const struct xlog_recover_item_ops xlog_attri_item_ops = {
        .item_type      = XFS_LI_ATTRI,
        .commit_pass2   = xlog_recover_attri_commit_pass2,
};

static const struct xfs_item_ops xfs_attrd_item_ops = {
        .flags          = XFS_ITEM_RELEASE_WHEN_COMMITTED |
                          XFS_ITEM_INTENT_DONE,
        .iop_size       = xfs_attrd_item_size,
        .iop_format     = xfs_attrd_item_format,
        .iop_release    = xfs_attrd_item_release,
        .iop_intent     = xfs_attrd_item_intent,
};

const struct xlog_recover_item_ops xlog_attrd_item_ops = {
        .item_type      = XFS_LI_ATTRD,
        .commit_pass2   = xlog_recover_attrd_commit_pass2,
};