diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_attr.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_attr.c | 1456 |
1 files changed, 1456 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..fcca36bbd --- /dev/null +++ b/fs/xfs/libxfs/xfs_attr.c @@ -0,0 +1,1456 @@ +// 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_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_trans.h" +#include "xfs_bmap.h" +#include "xfs_bmap_btree.h" +#include "xfs_attr.h" +#include "xfs_attr_leaf.h" +#include "xfs_attr_remote.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); +STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp); + +/* + * 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_node_hasname(xfs_da_args_t *args, + struct xfs_da_state **state); +STATIC int xfs_attr_fillstate(xfs_da_state_t *state); +STATIC int xfs_attr_refillstate(xfs_da_state_t *state); + +int +xfs_inode_hasattr( + struct xfs_inode *ip) +{ + if (!XFS_IFORK_Q(ip) || + (ip->i_afp->if_format == XFS_DINODE_FMT_EXTENTS && + ip->i_afp->if_nextents == 0)) + return 0; + return 1; +} + +/*======================================================================== + * Overall external interface routines. + *========================================================================*/ + +/* + * Retrieve an extended attribute and its value. Must have ilock. + * Returns 0 on successful retrieval, otherwise an error. + */ +int +xfs_attr_get_ilocked( + struct xfs_da_args *args) +{ + ASSERT(xfs_isilocked(args->dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); + + if (!xfs_inode_hasattr(args->dp)) + return -ENOATTR; + + if (args->dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL) + return xfs_attr_shortform_getvalue(args); + if (xfs_bmap_one_block(args->dp, XFS_ATTR_FORK)) + return xfs_attr_leaf_get(args); + return xfs_attr_node_get(args); +} + +/* + * Retrieve an extended attribute by name, and its value if requested. + * + * If args->valuelen is zero, then the caller does not want the value, just an + * indication whether the attribute exists and the size of the value if it + * exists. The size is returned in args.valuelen. + * + * If args->value is NULL but args->valuelen is non-zero, allocate the buffer + * for the value after existence of the attribute has been determined. The + * caller always has to free args->value if it is set, no matter if this + * function was successful or not. + * + * If the attribute is found, but exceeds the size limit set by the caller in + * args->valuelen, return -ERANGE with the size of the attribute that was found + * in args->valuelen. + */ +int +xfs_attr_get( + struct xfs_da_args *args) +{ + uint lock_mode; + int error; + + XFS_STATS_INC(args->dp->i_mount, xs_attr_get); + + if (XFS_FORCED_SHUTDOWN(args->dp->i_mount)) + return -EIO; + + args->geo = args->dp->i_mount->m_attr_geo; + args->whichfork = XFS_ATTR_FORK; + args->hashval = xfs_da_hashname(args->name, args->namelen); + + /* 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(args->dp); + error = xfs_attr_get_ilocked(args); + xfs_iunlock(args->dp, lock_mode); + + return 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) +{ + + int error; + + /* + * Build initial attribute list (if required). + */ + if (dp->i_afp->if_format == XFS_DINODE_FMT_EXTENTS) + xfs_attr_shortform_create(args); + + 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->op_flags & XFS_DA_OP_NOTIME)) + xfs_trans_ichgtime(args->trans, dp, XFS_ICHGTIME_CHG); + + if (dp->i_mount->m_flags & XFS_MOUNT_WSYNC) + xfs_trans_set_sync(args->trans); + + return error; +} + +/* + * Check to see if the attr should be upgraded from non-existent or shortform to + * single-leaf-block attribute list. + */ +static inline bool +xfs_attr_is_shortform( + struct xfs_inode *ip) +{ + return ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL || + (ip->i_afp->if_format == XFS_DINODE_FMT_EXTENTS && + ip->i_afp->if_nextents == 0); +} + +/* + * Attempts to set an attr in shortform, or converts short form to leaf form if + * there is not enough room. If the attr is set, the transaction is committed + * and set to NULL. + */ +STATIC int +xfs_attr_set_shortform( + struct xfs_da_args *args, + struct xfs_buf **leaf_bp) +{ + struct xfs_inode *dp = args->dp; + int error, error2 = 0; + + /* + * Try to add the attr to the attribute list in the inode. + */ + error = xfs_attr_try_sf_addname(dp, args); + if (error != -ENOSPC) { + error2 = xfs_trans_commit(args->trans); + args->trans = NULL; + return error ? error : error2; + } + /* + * 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; + } + + return 0; +} + +/* + * 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 = 0; + + /* + * If the attribute list is already in leaf format, jump straight to + * leaf handling. Otherwise, try to add the attribute to the shortform + * list; if there's no room then convert the list to leaf format and try + * again. + */ + if (xfs_attr_is_shortform(dp)) { + + /* + * If the attr was successfully set in shortform, the + * transaction is committed and set to NULL. Otherwise, is it + * converted from shortform to leaf, and the transaction is + * retained. + */ + error = xfs_attr_set_shortform(args, &leaf_bp); + if (error || !args->trans) + return error; + } + + if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { + error = xfs_attr_leaf_addname(args); + if (error != -ENOSPC) + return error; + + /* + * Promote the attribute list to the Btree format. + */ + error = xfs_attr3_leaf_to_node(args); + if (error) + return error; + + /* + * Finish any deferred work items and roll the transaction once + * more. The goal here is to call node_addname with the inode + * and transaction in the same state (inode locked and joined, + * transaction clean) no matter how we got to this step. + */ + 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; + } + + error = xfs_attr_node_addname(args); + return error; +} + +/* + * Return EEXIST if attr is found, or ENOATTR if not + */ +int +xfs_has_attr( + struct xfs_da_args *args) +{ + struct xfs_inode *dp = args->dp; + struct xfs_buf *bp = NULL; + int error; + + if (!xfs_inode_hasattr(dp)) + return -ENOATTR; + + if (dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL) { + ASSERT(dp->i_afp->if_flags & XFS_IFINLINE); + return xfs_attr_sf_findname(args, NULL, NULL); + } + + if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { + error = xfs_attr_leaf_hasname(args, &bp); + + if (bp) + xfs_trans_brelse(args->trans, bp); + + return error; + } + + return xfs_attr_node_hasname(args, NULL); +} + +/* + * 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_afp->if_format == 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; +} + +/* + * Note: If args->value is NULL the attribute will be removed, just like the + * Linux ->setattr API. + */ +int +xfs_attr_set( + struct xfs_da_args *args) +{ + struct xfs_inode *dp = args->dp; + struct xfs_mount *mp = dp->i_mount; + struct xfs_trans_res tres; + bool rsvd = (args->attr_filter & XFS_ATTR_ROOT); + int error, local; + unsigned int total; + + if (XFS_FORCED_SHUTDOWN(dp->i_mount)) + return -EIO; + + error = xfs_qm_dqattach(dp); + if (error) + return error; + + args->geo = mp->m_attr_geo; + args->whichfork = XFS_ATTR_FORK; + args->hashval = xfs_da_hashname(args->name, args->namelen); + + /* + * 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 as well. + */ + args->op_flags = XFS_DA_OP_OKNOENT; + + if (args->value) { + XFS_STATS_INC(mp, xs_attr_set); + + args->op_flags |= XFS_DA_OP_ADDNAME; + args->total = xfs_attr_calc_size(args, &local); + + /* + * 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(struct xfs_attr_sf_hdr) + + xfs_attr_sf_entsize_byname(args->namelen, + args->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; + total = args->total; + } else { + XFS_STATS_INC(mp, xs_attr_remove); + + tres = M_RES(mp)->tr_attrrm; + total = XFS_ATTRRM_SPACE_RES(mp); + } + + /* + * Root fork attributes can use reserved data blocks for this + * operation if necessary + */ + error = xfs_trans_alloc(mp, &tres, total, 0, + rsvd ? XFS_TRANS_RESERVE : 0, &args->trans); + if (error) + return error; + + xfs_ilock(dp, XFS_ILOCK_EXCL); + xfs_trans_ijoin(args->trans, dp, 0); + if (args->value) { + unsigned int quota_flags = XFS_QMOPT_RES_REGBLKS; + + if (rsvd) + quota_flags |= XFS_QMOPT_FORCE_RES; + error = xfs_trans_reserve_quota_nblks(args->trans, dp, + args->total, 0, quota_flags); + if (error) + goto out_trans_cancel; + + error = xfs_has_attr(args); + 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) + goto out_trans_cancel; + + error = xfs_attr_set_args(args); + if (error) + goto out_trans_cancel; + /* shortform attribute has already been committed */ + if (!args->trans) + goto out_unlock; + } else { + error = xfs_has_attr(args); + if (error != -EEXIST) + goto out_trans_cancel; + + error = xfs_attr_remove_args(args); + if (error) + goto out_trans_cancel; + } + + /* + * 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 (!(args->op_flags & XFS_DA_OP_NOTIME)) + 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; +} + +/*======================================================================== + * External routines when attribute list is inside the inode + *========================================================================*/ + +static inline int xfs_attr_sf_totsize(struct xfs_inode *dp) +{ + struct xfs_attr_shortform *sf; + + sf = (struct xfs_attr_shortform *)dp->i_afp->if_u1.if_data; + return be16_to_cpu(sf->hdr.totsize); +} + +/* + * 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 (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE)) + return retval; + if (retval == -EEXIST) { + if (args->attr_flags & XATTR_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->attr_flags &= ~XATTR_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 + *========================================================================*/ + +/* Store info about a remote block */ +STATIC void +xfs_attr_save_rmt_blk( + struct xfs_da_args *args) +{ + args->blkno2 = args->blkno; + args->index2 = args->index; + args->rmtblkno2 = args->rmtblkno; + args->rmtblkcnt2 = args->rmtblkcnt; + args->rmtvaluelen2 = args->rmtvaluelen; +} + +/* Set stored info about a remote block */ +STATIC void +xfs_attr_restore_rmt_blk( + struct xfs_da_args *args) +{ + args->blkno = args->blkno2; + args->index = args->index2; + args->rmtblkno = args->rmtblkno2; + args->rmtblkcnt = args->rmtblkcnt2; + args->rmtvaluelen = args->rmtvaluelen2; +} + +/* + * Tries to add an attribute to an inode in leaf form + * + * This function is meant to execute as part of a delayed operation and leaves + * the transaction handling to the caller. On success the attribute is added + * and the inode and transaction are left dirty. If there is not enough space, + * the attr data is converted to node format and -ENOSPC is returned. Caller is + * responsible for handling the dirty inode and transaction or adding the attr + * in node format. + */ +STATIC int +xfs_attr_leaf_try_add( + struct xfs_da_args *args, + struct xfs_buf *bp) +{ + int retval; + + /* + * 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_attr_leaf_hasname(args, &bp); + if (retval != -ENOATTR && retval != -EEXIST) + return retval; + if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE)) + goto out_brelse; + if (retval == -EEXIST) { + if (args->attr_flags & XATTR_CREATE) + goto out_brelse; + + trace_xfs_attr_leaf_replace(args); + + /* save the attribute state for later removal*/ + args->op_flags |= XFS_DA_OP_RENAME; /* an atomic rename */ + xfs_attr_save_rmt_blk(args); + + /* + * 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 + */ + return xfs_attr3_leaf_add(bp, args); + +out_brelse: + xfs_trans_brelse(args->trans, bp); + return retval; +} + + +/* + * 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) +{ + int error, forkoff; + struct xfs_buf *bp = NULL; + struct xfs_inode *dp = args->dp; + + trace_xfs_attr_leaf_addname(args); + + error = xfs_attr_leaf_try_add(args, bp); + if (error) + 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 (!(args->op_flags & XFS_DA_OP_RENAME)) { + /* + * Added a "remote" value, just clear the incomplete flag. + */ + if (args->rmtblkno > 0) + error = xfs_attr3_leaf_clearflag(args); + + 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. + * + * 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; + /* + * Commit the flag value change and start the next trans in series. + */ + error = xfs_trans_roll_inode(&args->trans, args->dp); + if (error) + return error; + + /* + * Dismantle the "old" attribute/value pair by removing a "remote" value + * (if it exists). + */ + xfs_attr_restore_rmt_blk(args); + + if (args->rmtblkno) { + error = xfs_attr_rmtval_invalidate(args); + if (error) + return error; + + 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, + &bp); + if (error) + return error; + + xfs_attr3_leaf_remove(bp, args); + + /* + * If the result is small enough, shrink it all into the inode. + */ + forkoff = xfs_attr_shortform_allfit(bp, dp); + if (forkoff) + error = xfs_attr3_leaf_to_shortform(bp, args, forkoff); + /* bp is gone due to xfs_da_shrink_inode */ + + return error; +} + +/* + * Return EEXIST if attr is found, or ENOATTR if not + */ +STATIC int +xfs_attr_leaf_hasname( + struct xfs_da_args *args, + struct xfs_buf **bp) +{ + int error = 0; + + error = xfs_attr3_leaf_read(args->trans, args->dp, 0, bp); + if (error) + return error; + + error = xfs_attr3_leaf_lookup_int(*bp, args); + if (error != -ENOATTR && error != -EEXIST) + xfs_trans_brelse(args->trans, *bp); + + 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; + + error = xfs_attr_leaf_hasname(args, &bp); + + if (error == -ENOATTR) { + xfs_trans_brelse(args->trans, bp); + return error; + } else if (error != -EEXIST) + return error; + + xfs_attr3_leaf_remove(bp, args); + + /* + * If the result is small enough, shrink it all into the inode. + */ + forkoff = xfs_attr_shortform_allfit(bp, dp); + if (forkoff) + return xfs_attr3_leaf_to_shortform(bp, args, forkoff); + /* bp is gone due to xfs_da_shrink_inode */ + + 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). + * + * Returns 0 on successful retrieval, otherwise an error. + */ +STATIC int +xfs_attr_leaf_get(xfs_da_args_t *args) +{ + struct xfs_buf *bp; + int error; + + trace_xfs_attr_leaf_get(args); + + error = xfs_attr_leaf_hasname(args, &bp); + + if (error == -ENOATTR) { + xfs_trans_brelse(args->trans, bp); + return error; + } else if (error != -EEXIST) + return error; + + + error = xfs_attr3_leaf_getvalue(bp, args); + xfs_trans_brelse(args->trans, bp); + return error; +} + +/* + * Return EEXIST if attr is found, or ENOATTR if not + * statep: If not null is set to point at the found state. Caller will + * be responsible for freeing the state in this case. + */ +STATIC int +xfs_attr_node_hasname( + struct xfs_da_args *args, + struct xfs_da_state **statep) +{ + struct xfs_da_state *state; + int retval, error; + + state = xfs_da_state_alloc(args); + if (statep != NULL) + *statep = state; + + /* + * 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; + + if (!statep) + xfs_da_state_free(state); + + return retval; +} + +/*======================================================================== + * 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; + int retval, error; + + trace_xfs_attr_node_addname(args); + + /* + * Fill in bucket of arguments/results/context to carry around. + */ + dp = args->dp; +restart: + /* + * Search to see if name already exists, and get back a pointer + * to where it should go. + */ + error = 0; + retval = xfs_attr_node_hasname(args, &state); + if (retval != -ENOATTR && retval != -EEXIST) + goto out; + + blk = &state->path.blk[ state->path.active-1 ]; + ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC); + if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE)) + goto out; + if (retval == -EEXIST) { + if (args->attr_flags & XATTR_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 */ + xfs_attr_save_rmt_blk(args); + + /* + * 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 (!(args->op_flags & XFS_DA_OP_RENAME)) { + /* + * Added a "remote" value, just clear the incomplete flag. + */ + if (args->rmtblkno > 0) + error = xfs_attr3_leaf_clearflag(args); + retval = error; + goto out; + } + + /* + * 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. + * + * 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; + /* + * Commit the flag value change and start the next trans in series + */ + error = xfs_trans_roll_inode(&args->trans, args->dp); + if (error) + goto out; + + /* + * Dismantle the "old" attribute/value pair by removing a "remote" value + * (if it exists). + */ + xfs_attr_restore_rmt_blk(args); + + if (args->rmtblkno) { + error = xfs_attr_rmtval_invalidate(args); + if (error) + return error; + + 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->attr_filter |= XFS_ATTR_INCOMPLETE; + state = xfs_da_state_alloc(args); + 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; + } + retval = error = 0; + +out: + if (state) + xfs_da_state_free(state); + if (error) + return error; + return retval; +} + +/* + * Shrink an attribute from leaf to shortform + */ +STATIC int +xfs_attr_node_shrink( + struct xfs_da_args *args, + struct xfs_da_state *state) +{ + struct xfs_inode *dp = args->dp; + int error, forkoff; + struct xfs_buf *bp; + + /* + * 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, &bp); + if (error) + return error; + + forkoff = xfs_attr_shortform_allfit(bp, dp); + if (forkoff) { + error = xfs_attr3_leaf_to_shortform(bp, args, forkoff); + /* bp is gone due to xfs_da_shrink_inode */ + } else + xfs_trans_brelse(args->trans, bp); + + return error; +} + +/* + * Mark an attribute entry INCOMPLETE and save pointers to the relevant buffers + * for later deletion of the entry. + */ +STATIC int +xfs_attr_leaf_mark_incomplete( + struct xfs_da_args *args, + struct xfs_da_state *state) +{ + int error; + + /* + * 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) + return error; + + /* + * Mark the attribute as INCOMPLETE + */ + return xfs_attr3_leaf_setflag(args); +} + +/* + * Initial setup for xfs_attr_node_removename. Make sure the attr is there and + * the blocks are valid. Attr keys with remote blocks will be marked + * incomplete. + */ +STATIC +int xfs_attr_node_removename_setup( + struct xfs_da_args *args, + struct xfs_da_state **state) +{ + int error; + + error = xfs_attr_node_hasname(args, state); + if (error != -EEXIST) + return error; + + ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL); + ASSERT((*state)->path.blk[(*state)->path.active - 1].magic == + XFS_ATTR_LEAF_MAGIC); + + if (args->rmtblkno > 0) { + error = xfs_attr_leaf_mark_incomplete(args, *state); + if (error) + return error; + + return xfs_attr_rmtval_invalidate(args); + } + + return 0; +} + +STATIC int +xfs_attr_node_remove_rmt( + struct xfs_da_args *args, + struct xfs_da_state *state) +{ + int error = 0; + + error = xfs_attr_rmtval_remove(args); + if (error) + return error; + + /* + * Refill the state structure with buffers, the prior calls released our + * buffers. + */ + return xfs_attr_refillstate(state); +} + +/* + * 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; + int retval, error; + struct xfs_inode *dp = args->dp; + + trace_xfs_attr_node_removename(args); + + error = xfs_attr_node_removename_setup(args, &state); + if (error) + 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. + */ + if (args->rmtblkno > 0) { + error = xfs_attr_node_remove_rmt(args, 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)) + error = xfs_attr_node_shrink(args, state); + +out: + if (state) + 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_mapped(state->args->trans, + state->args->dp, 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_mapped(state->args->trans, + state->args->dp, blk->disk_blkno, + &blk->bp, XFS_ATTR_FORK); + if (error) + return error; + } else { + blk->bp = NULL; + } + } + + return 0; +} + +/* + * Retrieve the attribute data from 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. + * + * Returns 0 on successful retrieval, otherwise an error. + */ +STATIC int +xfs_attr_node_get( + struct xfs_da_args *args) +{ + struct xfs_da_state *state; + struct xfs_da_state_blk *blk; + int i; + int error; + + trace_xfs_attr_node_get(args); + + /* + * Search to see if name exists, and get back a pointer to it. + */ + error = xfs_attr_node_hasname(args, &state); + if (error != -EEXIST) + goto out_release; + + /* + * Get the value, local or "remote" + */ + blk = &state->path.blk[state->path.active - 1]; + error = xfs_attr3_leaf_getvalue(blk->bp, args); + + /* + * If not in a transaction, we have to release all the buffers. + */ +out_release: + for (i = 0; state != NULL && i < state->path.active; i++) { + xfs_trans_brelse(args->trans, state->path.blk[i].bp); + state->path.blk[i].bp = NULL; + } + + if (state) + xfs_da_state_free(state); + return error; +} + +/* Returns true if the attribute entry name is valid. */ +bool +xfs_attr_namecheck( + const void *name, + size_t length) +{ + /* + * MAXNAMELEN includes the trailing null, but (name/length) leave it + * out, so use >= for the length check. + */ + if (length >= MAXNAMELEN) + return false; + + /* There shouldn't be any nulls here */ + return !memchr(name, 0, length); +} |