linux/fs/xfs/libxfs/xfs_attr.c
Darrick J. Wong 654805367d xfs: check attribute name validity
Check extended attribute entry names for invalid characters.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-11 16:06:40 -08:00

1356 lines
33 KiB
C

// 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_buf **leaf_bp)
{
struct xfs_inode *dp = args->dp;
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.
*/
xfs_trans_bhold(args->trans, *leaf_bp);
error = xfs_defer_finish(&args->trans);
if (error)
return error;
/*
* Commit the leaf transformation. We'll need another
* (linked) transaction to add the new attribute to the
* leaf.
*/
error = xfs_trans_roll_inode(&args->trans, dp);
if (error)
return error;
xfs_trans_bjoin(args->trans, *leaf_bp);
*leaf_bp = NULL;
}
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_buf *leaf_bp = NULL;
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, &leaf_bp);
if (error)
goto out_release_leaf;
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_release_leaf:
if (leaf_bp)
xfs_trans_brelse(args.trans, leaf_bp);
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;
}
/* 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);
}