summaryrefslogtreecommitdiffstats
path: root/fs/xfs/libxfs/xfs_attr.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/xfs/libxfs/xfs_attr.c')
-rw-r--r--fs/xfs/libxfs/xfs_attr.c1327
1 files changed, 1327 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
new file mode 100644
index 000000000..6410d3e00
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -0,0 +1,1327 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_attr_sf.h"
+#include "xfs_inode.h"
+#include "xfs_alloc.h"
+#include "xfs_trans.h"
+#include "xfs_inode_item.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_util.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_attr.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_attr_remote.h"
+#include "xfs_error.h"
+#include "xfs_quota.h"
+#include "xfs_trans_space.h"
+#include "xfs_trace.h"
+
+/*
+ * xfs_attr.c
+ *
+ * Provide the external interfaces to manage attribute lists.
+ */
+
+/*========================================================================
+ * Function prototypes for the kernel.
+ *========================================================================*/
+
+/*
+ * Internal routines when attribute list fits inside the inode.
+ */
+STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
+
+/*
+ * Internal routines when attribute list is one block.
+ */
+STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
+STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
+STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
+
+/*
+ * Internal routines when attribute list is more than one block.
+ */
+STATIC int xfs_attr_node_get(xfs_da_args_t *args);
+STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
+STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
+STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
+STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
+
+
+STATIC int
+xfs_attr_args_init(
+ struct xfs_da_args *args,
+ struct xfs_inode *dp,
+ const unsigned char *name,
+ int flags)
+{
+
+ if (!name)
+ return -EINVAL;
+
+ memset(args, 0, sizeof(*args));
+ args->geo = dp->i_mount->m_attr_geo;
+ args->whichfork = XFS_ATTR_FORK;
+ args->dp = dp;
+ args->flags = flags;
+ args->name = name;
+ args->namelen = strlen((const char *)name);
+ if (args->namelen >= MAXNAMELEN)
+ return -EFAULT; /* match IRIX behaviour */
+
+ args->hashval = xfs_da_hashname(args->name, args->namelen);
+ return 0;
+}
+
+int
+xfs_inode_hasattr(
+ struct xfs_inode *ip)
+{
+ if (!XFS_IFORK_Q(ip) ||
+ (ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
+ ip->i_d.di_anextents == 0))
+ return 0;
+ return 1;
+}
+
+/*========================================================================
+ * Overall external interface routines.
+ *========================================================================*/
+
+/* Retrieve an extended attribute and its value. Must have ilock. */
+int
+xfs_attr_get_ilocked(
+ struct xfs_inode *ip,
+ struct xfs_da_args *args)
+{
+ ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
+
+ if (!xfs_inode_hasattr(ip))
+ return -ENOATTR;
+ else if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL)
+ return xfs_attr_shortform_getvalue(args);
+ else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK))
+ return xfs_attr_leaf_get(args);
+ else
+ return xfs_attr_node_get(args);
+}
+
+/* Retrieve an extended attribute by name, and its value. */
+int
+xfs_attr_get(
+ struct xfs_inode *ip,
+ const unsigned char *name,
+ unsigned char *value,
+ int *valuelenp,
+ int flags)
+{
+ struct xfs_da_args args;
+ uint lock_mode;
+ int error;
+
+ XFS_STATS_INC(ip->i_mount, xs_attr_get);
+
+ if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+ return -EIO;
+
+ error = xfs_attr_args_init(&args, ip, name, flags);
+ if (error)
+ return error;
+
+ args.value = value;
+ args.valuelen = *valuelenp;
+ /* Entirely possible to look up a name which doesn't exist */
+ args.op_flags = XFS_DA_OP_OKNOENT;
+
+ lock_mode = xfs_ilock_attr_map_shared(ip);
+ error = xfs_attr_get_ilocked(ip, &args);
+ xfs_iunlock(ip, lock_mode);
+
+ *valuelenp = args.valuelen;
+ return error == -EEXIST ? 0 : error;
+}
+
+/*
+ * Calculate how many blocks we need for the new attribute,
+ */
+STATIC int
+xfs_attr_calc_size(
+ struct xfs_da_args *args,
+ int *local)
+{
+ struct xfs_mount *mp = args->dp->i_mount;
+ int size;
+ int nblks;
+
+ /*
+ * Determine space new attribute will use, and if it would be
+ * "local" or "remote" (note: local != inline).
+ */
+ size = xfs_attr_leaf_newentsize(args, local);
+ nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
+ if (*local) {
+ if (size > (args->geo->blksize / 2)) {
+ /* Double split possible */
+ nblks *= 2;
+ }
+ } else {
+ /*
+ * Out of line attribute, cannot double split, but
+ * make room for the attribute value itself.
+ */
+ uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
+ nblks += dblocks;
+ nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
+ }
+
+ return nblks;
+}
+
+STATIC int
+xfs_attr_try_sf_addname(
+ struct xfs_inode *dp,
+ struct xfs_da_args *args)
+{
+
+ struct xfs_mount *mp = dp->i_mount;
+ int error, error2;
+
+ error = xfs_attr_shortform_addname(args);
+ if (error == -ENOSPC)
+ return error;
+
+ /*
+ * Commit the shortform mods, and we're done.
+ * NOTE: this is also the error path (EEXIST, etc).
+ */
+ if (!error && (args->flags & ATTR_KERNOTIME) == 0)
+ xfs_trans_ichgtime(args->trans, dp, XFS_ICHGTIME_CHG);
+
+ if (mp->m_flags & XFS_MOUNT_WSYNC)
+ xfs_trans_set_sync(args->trans);
+
+ error2 = xfs_trans_commit(args->trans);
+ args->trans = NULL;
+ return error ? error : error2;
+}
+
+/*
+ * Set the attribute specified in @args.
+ */
+int
+xfs_attr_set_args(
+ struct xfs_da_args *args)
+{
+ struct xfs_inode *dp = args->dp;
+ struct xfs_buf *leaf_bp = NULL;
+ int error;
+
+ /*
+ * If the attribute list is non-existent or a shortform list,
+ * upgrade it to a single-leaf-block attribute list.
+ */
+ if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
+ (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
+ dp->i_d.di_anextents == 0)) {
+
+ /*
+ * Build initial attribute list (if required).
+ */
+ if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS)
+ xfs_attr_shortform_create(args);
+
+ /*
+ * Try to add the attr to the attribute list in the inode.
+ */
+ error = xfs_attr_try_sf_addname(dp, args);
+ if (error != -ENOSPC)
+ return error;
+
+ /*
+ * It won't fit in the shortform, transform to a leaf block.
+ * GROT: another possible req'mt for a double-split btree op.
+ */
+ error = xfs_attr_shortform_to_leaf(args, &leaf_bp);
+ if (error)
+ return error;
+
+ /*
+ * Prevent the leaf buffer from being unlocked so that a
+ * concurrent AIL push cannot grab the half-baked leaf
+ * buffer and run into problems with the write verifier.
+ * Once we're done rolling the transaction we can release
+ * the hold and add the attr to the leaf.
+ */
+ xfs_trans_bhold(args->trans, leaf_bp);
+ error = xfs_defer_finish(&args->trans);
+ xfs_trans_bhold_release(args->trans, leaf_bp);
+ if (error) {
+ xfs_trans_brelse(args->trans, leaf_bp);
+ return error;
+ }
+ }
+
+ if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
+ error = xfs_attr_leaf_addname(args);
+ else
+ error = xfs_attr_node_addname(args);
+ return error;
+}
+
+/*
+ * Remove the attribute specified in @args.
+ */
+int
+xfs_attr_remove_args(
+ struct xfs_da_args *args)
+{
+ struct xfs_inode *dp = args->dp;
+ int error;
+
+ if (!xfs_inode_hasattr(dp)) {
+ error = -ENOATTR;
+ } else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
+ ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
+ error = xfs_attr_shortform_remove(args);
+ } else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
+ error = xfs_attr_leaf_removename(args);
+ } else {
+ error = xfs_attr_node_removename(args);
+ }
+
+ return error;
+}
+
+int
+xfs_attr_set(
+ struct xfs_inode *dp,
+ const unsigned char *name,
+ unsigned char *value,
+ int valuelen,
+ int flags)
+{
+ struct xfs_mount *mp = dp->i_mount;
+ struct xfs_da_args args;
+ struct xfs_trans_res tres;
+ int rsvd = (flags & ATTR_ROOT) != 0;
+ int error, local;
+
+ XFS_STATS_INC(mp, xs_attr_set);
+
+ if (XFS_FORCED_SHUTDOWN(dp->i_mount))
+ return -EIO;
+
+ error = xfs_attr_args_init(&args, dp, name, flags);
+ if (error)
+ return error;
+
+ args.value = value;
+ args.valuelen = valuelen;
+ args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
+ args.total = xfs_attr_calc_size(&args, &local);
+
+ error = xfs_qm_dqattach(dp);
+ if (error)
+ return error;
+
+ /*
+ * If the inode doesn't have an attribute fork, add one.
+ * (inode must not be locked when we call this routine)
+ */
+ if (XFS_IFORK_Q(dp) == 0) {
+ int sf_size = sizeof(xfs_attr_sf_hdr_t) +
+ XFS_ATTR_SF_ENTSIZE_BYNAME(args.namelen, valuelen);
+
+ error = xfs_bmap_add_attrfork(dp, sf_size, rsvd);
+ if (error)
+ return error;
+ }
+
+ tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
+ M_RES(mp)->tr_attrsetrt.tr_logres * args.total;
+ tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
+ tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
+
+ /*
+ * Root fork attributes can use reserved data blocks for this
+ * operation if necessary
+ */
+ error = xfs_trans_alloc(mp, &tres, args.total, 0,
+ rsvd ? XFS_TRANS_RESERVE : 0, &args.trans);
+ if (error)
+ return error;
+
+ xfs_ilock(dp, XFS_ILOCK_EXCL);
+ error = xfs_trans_reserve_quota_nblks(args.trans, dp, args.total, 0,
+ rsvd ? XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
+ XFS_QMOPT_RES_REGBLKS);
+ if (error)
+ goto out_trans_cancel;
+
+ xfs_trans_ijoin(args.trans, dp, 0);
+ error = xfs_attr_set_args(&args);
+ if (error)
+ goto out_trans_cancel;
+ if (!args.trans) {
+ /* shortform attribute has already been committed */
+ goto out_unlock;
+ }
+
+ /*
+ * If this is a synchronous mount, make sure that the
+ * transaction goes to disk before returning to the user.
+ */
+ if (mp->m_flags & XFS_MOUNT_WSYNC)
+ xfs_trans_set_sync(args.trans);
+
+ if ((flags & ATTR_KERNOTIME) == 0)
+ xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
+
+ /*
+ * Commit the last in the sequence of transactions.
+ */
+ xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
+ error = xfs_trans_commit(args.trans);
+out_unlock:
+ xfs_iunlock(dp, XFS_ILOCK_EXCL);
+ return error;
+
+out_trans_cancel:
+ if (args.trans)
+ xfs_trans_cancel(args.trans);
+ goto out_unlock;
+}
+
+/*
+ * Generic handler routine to remove a name from an attribute list.
+ * Transitions attribute list from Btree to shortform as necessary.
+ */
+int
+xfs_attr_remove(
+ struct xfs_inode *dp,
+ const unsigned char *name,
+ int flags)
+{
+ struct xfs_mount *mp = dp->i_mount;
+ struct xfs_da_args args;
+ int error;
+
+ XFS_STATS_INC(mp, xs_attr_remove);
+
+ if (XFS_FORCED_SHUTDOWN(dp->i_mount))
+ return -EIO;
+
+ error = xfs_attr_args_init(&args, dp, name, flags);
+ if (error)
+ return error;
+
+ /*
+ * we have no control over the attribute names that userspace passes us
+ * to remove, so we have to allow the name lookup prior to attribute
+ * removal to fail.
+ */
+ args.op_flags = XFS_DA_OP_OKNOENT;
+
+ error = xfs_qm_dqattach(dp);
+ if (error)
+ return error;
+
+ /*
+ * Root fork attributes can use reserved data blocks for this
+ * operation if necessary
+ */
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrrm,
+ XFS_ATTRRM_SPACE_RES(mp), 0,
+ (flags & ATTR_ROOT) ? XFS_TRANS_RESERVE : 0,
+ &args.trans);
+ if (error)
+ return error;
+
+ xfs_ilock(dp, XFS_ILOCK_EXCL);
+ /*
+ * No need to make quota reservations here. We expect to release some
+ * blocks not allocate in the common case.
+ */
+ xfs_trans_ijoin(args.trans, dp, 0);
+
+ error = xfs_attr_remove_args(&args);
+ if (error)
+ goto out;
+
+ /*
+ * If this is a synchronous mount, make sure that the
+ * transaction goes to disk before returning to the user.
+ */
+ if (mp->m_flags & XFS_MOUNT_WSYNC)
+ xfs_trans_set_sync(args.trans);
+
+ if ((flags & ATTR_KERNOTIME) == 0)
+ xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
+
+ /*
+ * Commit the last in the sequence of transactions.
+ */
+ xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
+ error = xfs_trans_commit(args.trans);
+ xfs_iunlock(dp, XFS_ILOCK_EXCL);
+
+ return error;
+
+out:
+ if (args.trans)
+ xfs_trans_cancel(args.trans);
+ xfs_iunlock(dp, XFS_ILOCK_EXCL);
+ return error;
+}
+
+/*========================================================================
+ * External routines when attribute list is inside the inode
+ *========================================================================*/
+
+/*
+ * Add a name to the shortform attribute list structure
+ * This is the external routine.
+ */
+STATIC int
+xfs_attr_shortform_addname(xfs_da_args_t *args)
+{
+ int newsize, forkoff, retval;
+
+ trace_xfs_attr_sf_addname(args);
+
+ retval = xfs_attr_shortform_lookup(args);
+ if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
+ return retval;
+ } else if (retval == -EEXIST) {
+ if (args->flags & ATTR_CREATE)
+ return retval;
+ retval = xfs_attr_shortform_remove(args);
+ if (retval)
+ return retval;
+ /*
+ * Since we have removed the old attr, clear ATTR_REPLACE so
+ * that the leaf format add routine won't trip over the attr
+ * not being around.
+ */
+ args->flags &= ~ATTR_REPLACE;
+ }
+
+ if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
+ args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
+ return -ENOSPC;
+
+ newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
+ newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
+
+ forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
+ if (!forkoff)
+ return -ENOSPC;
+
+ xfs_attr_shortform_add(args, forkoff);
+ return 0;
+}
+
+
+/*========================================================================
+ * External routines when attribute list is one block
+ *========================================================================*/
+
+/*
+ * Add a name to the leaf attribute list structure
+ *
+ * This leaf block cannot have a "remote" value, we only call this routine
+ * if bmap_one_block() says there is only one block (ie: no remote blks).
+ */
+STATIC int
+xfs_attr_leaf_addname(
+ struct xfs_da_args *args)
+{
+ struct xfs_inode *dp;
+ struct xfs_buf *bp;
+ int retval, error, forkoff;
+
+ trace_xfs_attr_leaf_addname(args);
+
+ /*
+ * Read the (only) block in the attribute list in.
+ */
+ dp = args->dp;
+ args->blkno = 0;
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+ if (error)
+ return error;
+
+ /*
+ * Look up the given attribute in the leaf block. Figure out if
+ * the given flags produce an error or call for an atomic rename.
+ */
+ retval = xfs_attr3_leaf_lookup_int(bp, args);
+ if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
+ xfs_trans_brelse(args->trans, bp);
+ return retval;
+ } else if (retval == -EEXIST) {
+ if (args->flags & ATTR_CREATE) { /* pure create op */
+ xfs_trans_brelse(args->trans, bp);
+ return retval;
+ }
+
+ trace_xfs_attr_leaf_replace(args);
+
+ /* save the attribute state for later removal*/
+ args->op_flags |= XFS_DA_OP_RENAME; /* an atomic rename */
+ args->blkno2 = args->blkno; /* set 2nd entry info*/
+ args->index2 = args->index;
+ args->rmtblkno2 = args->rmtblkno;
+ args->rmtblkcnt2 = args->rmtblkcnt;
+ args->rmtvaluelen2 = args->rmtvaluelen;
+
+ /*
+ * clear the remote attr state now that it is saved so that the
+ * values reflect the state of the attribute we are about to
+ * add, not the attribute we just found and will remove later.
+ */
+ args->rmtblkno = 0;
+ args->rmtblkcnt = 0;
+ args->rmtvaluelen = 0;
+ }
+
+ /*
+ * Add the attribute to the leaf block, transitioning to a Btree
+ * if required.
+ */
+ retval = xfs_attr3_leaf_add(bp, args);
+ if (retval == -ENOSPC) {
+ /*
+ * Promote the attribute list to the Btree format, then
+ * Commit that transaction so that the node_addname() call
+ * can manage its own transactions.
+ */
+ error = xfs_attr3_leaf_to_node(args);
+ if (error)
+ return error;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ return error;
+
+ /*
+ * Commit the current trans (including the inode) and start
+ * a new one.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ return error;
+
+ /*
+ * Fob the whole rest of the problem off on the Btree code.
+ */
+ error = xfs_attr_node_addname(args);
+ return error;
+ }
+
+ /*
+ * Commit the transaction that added the attr name so that
+ * later routines can manage their own transactions.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ return error;
+
+ /*
+ * If there was an out-of-line value, allocate the blocks we
+ * identified for its storage and copy the value. This is done
+ * after we create the attribute so that we don't overflow the
+ * maximum size of a transaction and/or hit a deadlock.
+ */
+ if (args->rmtblkno > 0) {
+ error = xfs_attr_rmtval_set(args);
+ if (error)
+ return error;
+ }
+
+ /*
+ * If this is an atomic rename operation, we must "flip" the
+ * incomplete flags on the "new" and "old" attribute/value pairs
+ * so that one disappears and one appears atomically. Then we
+ * must remove the "old" attribute/value pair.
+ */
+ if (args->op_flags & XFS_DA_OP_RENAME) {
+ /*
+ * In a separate transaction, set the incomplete flag on the
+ * "old" attr and clear the incomplete flag on the "new" attr.
+ */
+ error = xfs_attr3_leaf_flipflags(args);
+ if (error)
+ return error;
+
+ /*
+ * Dismantle the "old" attribute/value pair by removing
+ * a "remote" value (if it exists).
+ */
+ args->index = args->index2;
+ args->blkno = args->blkno2;
+ args->rmtblkno = args->rmtblkno2;
+ args->rmtblkcnt = args->rmtblkcnt2;
+ args->rmtvaluelen = args->rmtvaluelen2;
+ if (args->rmtblkno) {
+ error = xfs_attr_rmtval_remove(args);
+ if (error)
+ return error;
+ }
+
+ /*
+ * Read in the block containing the "old" attr, then
+ * remove the "old" attr from that block (neat, huh!)
+ */
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
+ -1, &bp);
+ if (error)
+ return error;
+
+ xfs_attr3_leaf_remove(bp, args);
+
+ /*
+ * If the result is small enough, shrink it all into the inode.
+ */
+ if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
+ error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
+ /* bp is gone due to xfs_da_shrink_inode */
+ if (error)
+ return error;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ return error;
+ }
+
+ /*
+ * Commit the remove and start the next trans in series.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+
+ } else if (args->rmtblkno > 0) {
+ /*
+ * Added a "remote" value, just clear the incomplete flag.
+ */
+ error = xfs_attr3_leaf_clearflag(args);
+ }
+ return error;
+}
+
+/*
+ * Remove a name from the leaf attribute list structure
+ *
+ * This leaf block cannot have a "remote" value, we only call this routine
+ * if bmap_one_block() says there is only one block (ie: no remote blks).
+ */
+STATIC int
+xfs_attr_leaf_removename(
+ struct xfs_da_args *args)
+{
+ struct xfs_inode *dp;
+ struct xfs_buf *bp;
+ int error, forkoff;
+
+ trace_xfs_attr_leaf_removename(args);
+
+ /*
+ * Remove the attribute.
+ */
+ dp = args->dp;
+ args->blkno = 0;
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+ if (error)
+ return error;
+
+ error = xfs_attr3_leaf_lookup_int(bp, args);
+ if (error == -ENOATTR) {
+ xfs_trans_brelse(args->trans, bp);
+ return error;
+ }
+
+ xfs_attr3_leaf_remove(bp, args);
+
+ /*
+ * If the result is small enough, shrink it all into the inode.
+ */
+ if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
+ error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
+ /* bp is gone due to xfs_da_shrink_inode */
+ if (error)
+ return error;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ return error;
+ }
+ return 0;
+}
+
+/*
+ * Look up a name in a leaf attribute list structure.
+ *
+ * This leaf block cannot have a "remote" value, we only call this routine
+ * if bmap_one_block() says there is only one block (ie: no remote blks).
+ */
+STATIC int
+xfs_attr_leaf_get(xfs_da_args_t *args)
+{
+ struct xfs_buf *bp;
+ int error;
+
+ trace_xfs_attr_leaf_get(args);
+
+ args->blkno = 0;
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+ if (error)
+ return error;
+
+ error = xfs_attr3_leaf_lookup_int(bp, args);
+ if (error != -EEXIST) {
+ xfs_trans_brelse(args->trans, bp);
+ return error;
+ }
+ error = xfs_attr3_leaf_getvalue(bp, args);
+ xfs_trans_brelse(args->trans, bp);
+ if (!error && (args->rmtblkno > 0) && !(args->flags & ATTR_KERNOVAL)) {
+ error = xfs_attr_rmtval_get(args);
+ }
+ return error;
+}
+
+/*========================================================================
+ * External routines when attribute list size > geo->blksize
+ *========================================================================*/
+
+/*
+ * Add a name to a Btree-format attribute list.
+ *
+ * This will involve walking down the Btree, and may involve splitting
+ * leaf nodes and even splitting intermediate nodes up to and including
+ * the root node (a special case of an intermediate node).
+ *
+ * "Remote" attribute values confuse the issue and atomic rename operations
+ * add a whole extra layer of confusion on top of that.
+ */
+STATIC int
+xfs_attr_node_addname(
+ struct xfs_da_args *args)
+{
+ struct xfs_da_state *state;
+ struct xfs_da_state_blk *blk;
+ struct xfs_inode *dp;
+ struct xfs_mount *mp;
+ int retval, error;
+
+ trace_xfs_attr_node_addname(args);
+
+ /*
+ * Fill in bucket of arguments/results/context to carry around.
+ */
+ dp = args->dp;
+ mp = dp->i_mount;
+restart:
+ state = xfs_da_state_alloc();
+ state->args = args;
+ state->mp = mp;
+
+ /*
+ * Search to see if name already exists, and get back a pointer
+ * to where it should go.
+ */
+ error = xfs_da3_node_lookup_int(state, &retval);
+ if (error)
+ goto out;
+ blk = &state->path.blk[ state->path.active-1 ];
+ ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
+ if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
+ goto out;
+ } else if (retval == -EEXIST) {
+ if (args->flags & ATTR_CREATE)
+ goto out;
+
+ trace_xfs_attr_node_replace(args);
+
+ /* save the attribute state for later removal*/
+ args->op_flags |= XFS_DA_OP_RENAME; /* atomic rename op */
+ args->blkno2 = args->blkno; /* set 2nd entry info*/
+ args->index2 = args->index;
+ args->rmtblkno2 = args->rmtblkno;
+ args->rmtblkcnt2 = args->rmtblkcnt;
+ args->rmtvaluelen2 = args->rmtvaluelen;
+
+ /*
+ * clear the remote attr state now that it is saved so that the
+ * values reflect the state of the attribute we are about to
+ * add, not the attribute we just found and will remove later.
+ */
+ args->rmtblkno = 0;
+ args->rmtblkcnt = 0;
+ args->rmtvaluelen = 0;
+ }
+
+ retval = xfs_attr3_leaf_add(blk->bp, state->args);
+ if (retval == -ENOSPC) {
+ if (state->path.active == 1) {
+ /*
+ * Its really a single leaf node, but it had
+ * out-of-line values so it looked like it *might*
+ * have been a b-tree.
+ */
+ xfs_da_state_free(state);
+ state = NULL;
+ error = xfs_attr3_leaf_to_node(args);
+ if (error)
+ goto out;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ goto out;
+
+ /*
+ * Commit the node conversion and start the next
+ * trans in the chain.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ goto out;
+
+ goto restart;
+ }
+
+ /*
+ * Split as many Btree elements as required.
+ * This code tracks the new and old attr's location
+ * in the index/blkno/rmtblkno/rmtblkcnt fields and
+ * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
+ */
+ error = xfs_da3_split(state);
+ if (error)
+ goto out;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ goto out;
+ } else {
+ /*
+ * Addition succeeded, update Btree hashvals.
+ */
+ xfs_da3_fixhashpath(state, &state->path);
+ }
+
+ /*
+ * Kill the state structure, we're done with it and need to
+ * allow the buffers to come back later.
+ */
+ xfs_da_state_free(state);
+ state = NULL;
+
+ /*
+ * Commit the leaf addition or btree split and start the next
+ * trans in the chain.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ goto out;
+
+ /*
+ * If there was an out-of-line value, allocate the blocks we
+ * identified for its storage and copy the value. This is done
+ * after we create the attribute so that we don't overflow the
+ * maximum size of a transaction and/or hit a deadlock.
+ */
+ if (args->rmtblkno > 0) {
+ error = xfs_attr_rmtval_set(args);
+ if (error)
+ return error;
+ }
+
+ /*
+ * If this is an atomic rename operation, we must "flip" the
+ * incomplete flags on the "new" and "old" attribute/value pairs
+ * so that one disappears and one appears atomically. Then we
+ * must remove the "old" attribute/value pair.
+ */
+ if (args->op_flags & XFS_DA_OP_RENAME) {
+ /*
+ * In a separate transaction, set the incomplete flag on the
+ * "old" attr and clear the incomplete flag on the "new" attr.
+ */
+ error = xfs_attr3_leaf_flipflags(args);
+ if (error)
+ goto out;
+
+ /*
+ * Dismantle the "old" attribute/value pair by removing
+ * a "remote" value (if it exists).
+ */
+ args->index = args->index2;
+ args->blkno = args->blkno2;
+ args->rmtblkno = args->rmtblkno2;
+ args->rmtblkcnt = args->rmtblkcnt2;
+ args->rmtvaluelen = args->rmtvaluelen2;
+ if (args->rmtblkno) {
+ error = xfs_attr_rmtval_remove(args);
+ if (error)
+ return error;
+ }
+
+ /*
+ * Re-find the "old" attribute entry after any split ops.
+ * The INCOMPLETE flag means that we will find the "old"
+ * attr, not the "new" one.
+ */
+ args->flags |= XFS_ATTR_INCOMPLETE;
+ state = xfs_da_state_alloc();
+ state->args = args;
+ state->mp = mp;
+ state->inleaf = 0;
+ error = xfs_da3_node_lookup_int(state, &retval);
+ if (error)
+ goto out;
+
+ /*
+ * Remove the name and update the hashvals in the tree.
+ */
+ blk = &state->path.blk[ state->path.active-1 ];
+ ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
+ error = xfs_attr3_leaf_remove(blk->bp, args);
+ xfs_da3_fixhashpath(state, &state->path);
+
+ /*
+ * Check to see if the tree needs to be collapsed.
+ */
+ if (retval && (state->path.active > 1)) {
+ error = xfs_da3_join(state);
+ if (error)
+ goto out;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ goto out;
+ }
+
+ /*
+ * Commit and start the next trans in the chain.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ goto out;
+
+ } else if (args->rmtblkno > 0) {
+ /*
+ * Added a "remote" value, just clear the incomplete flag.
+ */
+ error = xfs_attr3_leaf_clearflag(args);
+ if (error)
+ goto out;
+ }
+ retval = error = 0;
+
+out:
+ if (state)
+ xfs_da_state_free(state);
+ if (error)
+ return error;
+ return retval;
+}
+
+/*
+ * Remove a name from a B-tree attribute list.
+ *
+ * This will involve walking down the Btree, and may involve joining
+ * leaf nodes and even joining intermediate nodes up to and including
+ * the root node (a special case of an intermediate node).
+ */
+STATIC int
+xfs_attr_node_removename(
+ struct xfs_da_args *args)
+{
+ struct xfs_da_state *state;
+ struct xfs_da_state_blk *blk;
+ struct xfs_inode *dp;
+ struct xfs_buf *bp;
+ int retval, error, forkoff;
+
+ trace_xfs_attr_node_removename(args);
+
+ /*
+ * Tie a string around our finger to remind us where we are.
+ */
+ dp = args->dp;
+ state = xfs_da_state_alloc();
+ state->args = args;
+ state->mp = dp->i_mount;
+
+ /*
+ * Search to see if name exists, and get back a pointer to it.
+ */
+ error = xfs_da3_node_lookup_int(state, &retval);
+ if (error || (retval != -EEXIST)) {
+ if (error == 0)
+ error = retval;
+ goto out;
+ }
+
+ /*
+ * If there is an out-of-line value, de-allocate the blocks.
+ * This is done before we remove the attribute so that we don't
+ * overflow the maximum size of a transaction and/or hit a deadlock.
+ */
+ blk = &state->path.blk[ state->path.active-1 ];
+ ASSERT(blk->bp != NULL);
+ ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
+ if (args->rmtblkno > 0) {
+ /*
+ * Fill in disk block numbers in the state structure
+ * so that we can get the buffers back after we commit
+ * several transactions in the following calls.
+ */
+ error = xfs_attr_fillstate(state);
+ if (error)
+ goto out;
+
+ /*
+ * Mark the attribute as INCOMPLETE, then bunmapi() the
+ * remote value.
+ */
+ error = xfs_attr3_leaf_setflag(args);
+ if (error)
+ goto out;
+ error = xfs_attr_rmtval_remove(args);
+ if (error)
+ goto out;
+
+ /*
+ * Refill the state structure with buffers, the prior calls
+ * released our buffers.
+ */
+ error = xfs_attr_refillstate(state);
+ if (error)
+ goto out;
+ }
+
+ /*
+ * Remove the name and update the hashvals in the tree.
+ */
+ blk = &state->path.blk[ state->path.active-1 ];
+ ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
+ retval = xfs_attr3_leaf_remove(blk->bp, args);
+ xfs_da3_fixhashpath(state, &state->path);
+
+ /*
+ * Check to see if the tree needs to be collapsed.
+ */
+ if (retval && (state->path.active > 1)) {
+ error = xfs_da3_join(state);
+ if (error)
+ goto out;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ goto out;
+ /*
+ * Commit the Btree join operation and start a new trans.
+ */
+ error = xfs_trans_roll_inode(&args->trans, dp);
+ if (error)
+ goto out;
+ }
+
+ /*
+ * If the result is small enough, push it all into the inode.
+ */
+ if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
+ /*
+ * Have to get rid of the copy of this dabuf in the state.
+ */
+ ASSERT(state->path.active == 1);
+ ASSERT(state->path.blk[0].bp);
+ state->path.blk[0].bp = NULL;
+
+ error = xfs_attr3_leaf_read(args->trans, args->dp, 0, -1, &bp);
+ if (error)
+ goto out;
+
+ if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
+ error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
+ /* bp is gone due to xfs_da_shrink_inode */
+ if (error)
+ goto out;
+ error = xfs_defer_finish(&args->trans);
+ if (error)
+ goto out;
+ } else
+ xfs_trans_brelse(args->trans, bp);
+ }
+ error = 0;
+
+out:
+ xfs_da_state_free(state);
+ return error;
+}
+
+/*
+ * Fill in the disk block numbers in the state structure for the buffers
+ * that are attached to the state structure.
+ * This is done so that we can quickly reattach ourselves to those buffers
+ * after some set of transaction commits have released these buffers.
+ */
+STATIC int
+xfs_attr_fillstate(xfs_da_state_t *state)
+{
+ xfs_da_state_path_t *path;
+ xfs_da_state_blk_t *blk;
+ int level;
+
+ trace_xfs_attr_fillstate(state->args);
+
+ /*
+ * Roll down the "path" in the state structure, storing the on-disk
+ * block number for those buffers in the "path".
+ */
+ path = &state->path;
+ ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
+ for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
+ if (blk->bp) {
+ blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
+ blk->bp = NULL;
+ } else {
+ blk->disk_blkno = 0;
+ }
+ }
+
+ /*
+ * Roll down the "altpath" in the state structure, storing the on-disk
+ * block number for those buffers in the "altpath".
+ */
+ path = &state->altpath;
+ ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
+ for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
+ if (blk->bp) {
+ blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
+ blk->bp = NULL;
+ } else {
+ blk->disk_blkno = 0;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Reattach the buffers to the state structure based on the disk block
+ * numbers stored in the state structure.
+ * This is done after some set of transaction commits have released those
+ * buffers from our grip.
+ */
+STATIC int
+xfs_attr_refillstate(xfs_da_state_t *state)
+{
+ xfs_da_state_path_t *path;
+ xfs_da_state_blk_t *blk;
+ int level, error;
+
+ trace_xfs_attr_refillstate(state->args);
+
+ /*
+ * Roll down the "path" in the state structure, storing the on-disk
+ * block number for those buffers in the "path".
+ */
+ path = &state->path;
+ ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
+ for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
+ if (blk->disk_blkno) {
+ error = xfs_da3_node_read(state->args->trans,
+ state->args->dp,
+ blk->blkno, blk->disk_blkno,
+ &blk->bp, XFS_ATTR_FORK);
+ if (error)
+ return error;
+ } else {
+ blk->bp = NULL;
+ }
+ }
+
+ /*
+ * Roll down the "altpath" in the state structure, storing the on-disk
+ * block number for those buffers in the "altpath".
+ */
+ path = &state->altpath;
+ ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
+ for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
+ if (blk->disk_blkno) {
+ error = xfs_da3_node_read(state->args->trans,
+ state->args->dp,
+ blk->blkno, blk->disk_blkno,
+ &blk->bp, XFS_ATTR_FORK);
+ if (error)
+ return error;
+ } else {
+ blk->bp = NULL;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Look up a filename in a node attribute list.
+ *
+ * This routine gets called for any attribute fork that has more than one
+ * block, ie: both true Btree attr lists and for single-leaf-blocks with
+ * "remote" values taking up more blocks.
+ */
+STATIC int
+xfs_attr_node_get(xfs_da_args_t *args)
+{
+ xfs_da_state_t *state;
+ xfs_da_state_blk_t *blk;
+ int error, retval;
+ int i;
+
+ trace_xfs_attr_node_get(args);
+
+ state = xfs_da_state_alloc();
+ state->args = args;
+ state->mp = args->dp->i_mount;
+
+ /*
+ * Search to see if name exists, and get back a pointer to it.
+ */
+ error = xfs_da3_node_lookup_int(state, &retval);
+ if (error) {
+ retval = error;
+ } else if (retval == -EEXIST) {
+ blk = &state->path.blk[ state->path.active-1 ];
+ ASSERT(blk->bp != NULL);
+ ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
+
+ /*
+ * Get the value, local or "remote"
+ */
+ retval = xfs_attr3_leaf_getvalue(blk->bp, args);
+ if (!retval && (args->rmtblkno > 0)
+ && !(args->flags & ATTR_KERNOVAL)) {
+ retval = xfs_attr_rmtval_get(args);
+ }
+ }
+
+ /*
+ * If not in a transaction, we have to release all the buffers.
+ */
+ for (i = 0; i < state->path.active; i++) {
+ xfs_trans_brelse(args->trans, state->path.blk[i].bp);
+ state->path.blk[i].bp = NULL;
+ }
+
+ xfs_da_state_free(state);
+ return retval;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-24 04:24:42 +0000