// 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"
#include "xfs_attr_item.h"
#include "xfs_xattr.h"
#include "xfs_parent.h"
struct kmem_cache *xfs_attr_intent_cache;
/*
* 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_removename(xfs_da_args_t *args);
STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
STATIC int xfs_attr_leaf_try_add(struct xfs_da_args *args);
/*
* Internal routines when attribute list is more than one block.
*/
STATIC int xfs_attr_node_get(xfs_da_args_t *args);
STATIC void xfs_attr_restore_rmt_blk(struct xfs_da_args *args);
static int xfs_attr_node_try_addname(struct xfs_attr_intent *attr);
STATIC int xfs_attr_node_addname_find_attr(struct xfs_attr_intent *attr);
STATIC int xfs_attr_node_remove_attr(struct xfs_attr_intent *attr);
STATIC int xfs_attr_node_lookup(struct xfs_da_args *args,
struct xfs_da_state *state);
int
xfs_inode_hasattr(
struct xfs_inode *ip)
{
if (!xfs_inode_has_attr_fork(ip))
return 0;
if (ip->i_af.if_format == XFS_DINODE_FMT_EXTENTS &&
ip->i_af.if_nextents == 0)
return 0;
return 1;
}
/*
* Returns true if the there is exactly only block in the attr fork, in which
* case the attribute fork consists of a single leaf block entry.
*/
bool
xfs_attr_is_leaf(
struct xfs_inode *ip)
{
struct xfs_ifork *ifp = &ip->i_af;
struct xfs_iext_cursor icur;
struct xfs_bmbt_irec imap;
ASSERT(!xfs_need_iread_extents(ifp));
if (ifp->if_nextents != 1 || ifp->if_format != XFS_DINODE_FMT_EXTENTS)
return false;
xfs_iext_first(ifp, &icur);
xfs_iext_get_extent(ifp, &icur, &imap);
return imap.br_startoff == 0 && imap.br_blockcount == 1;
}
/*
* XXX (dchinner): name path state saving and refilling is an optimisation to
* avoid needing to look up name entries after rolling transactions removing
* remote xattr blocks between the name entry lookup and name entry removal.
* This optimisation got sidelined when combining the set and remove state
* machines, but the code has been left in place because it is worthwhile to
* restore the optimisation once the combined state machine paths have settled.
*
* This comment is a public service announcement to remind Future Dave that he
* still needs to restore this code to working order.
*/
#if 0
/*
* 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_daddr(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_daddr(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;
}
#else
static int xfs_attr_fillstate(xfs_da_state_t *state) { return 0; }
#endif
/*========================================================================
* 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)
{
int error;
xfs_assert_ilocked(args->dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL);
if (!xfs_inode_hasattr(args->dp))
return -ENOATTR;
/*
* The incore attr fork iext tree must be loaded for xfs_attr_is_leaf
* to work correctly.
*/
error = xfs_iread_extents(args->trans, args->dp, XFS_ATTR_FORK);
if (error)
return error;
if (args->dp->i_af.if_format == XFS_DINODE_FMT_LOCAL)
return xfs_attr_shortform_getvalue(args);
if (xfs_attr_is_leaf(args->dp))
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_is_shutdown(args->dp->i_mount))
return -EIO;
if (!args->owner)
args->owner = args->dp->i_ino;
args->geo = args->dp->i_mount->m_attr_geo;
args->whichfork = XFS_ATTR_FORK;
xfs_attr_sethash(args);
/* 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,
*/
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;
}
/* Initialize transaction reservation for an xattr set/replace/upsert */
inline struct xfs_trans_res
xfs_attr_set_resv(
const struct xfs_da_args *args)
{
struct xfs_mount *mp = args->dp->i_mount;
struct xfs_trans_res ret = {
.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
M_RES(mp)->tr_attrsetrt.tr_logres * args->total,
.tr_logcount = XFS_ATTRSET_LOG_COUNT,
.tr_logflags = XFS_TRANS_PERM_LOG_RES,
};
return ret;
}
/*
* Add an attr to a shortform fork. If there is no space,
* xfs_attr_shortform_addname() will convert to leaf format and return -ENOSPC.
* to use.
*/
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_af.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)
xfs_trans_ichgtime(args->trans, dp, XFS_ICHGTIME_CHG);
if (xfs_has_wsync(dp->i_mount))
xfs_trans_set_sync(args->trans);
return error;
}
static int
xfs_attr_sf_addname(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
struct xfs_inode *dp = args->dp;
int error = 0;
error = xfs_attr_try_sf_addname(dp, args);
if (error != -ENOSPC) {
ASSERT(!error || error == -EEXIST);
attr->xattri_dela_state = XFS_DAS_DONE;
goto out;
}
/*
* 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);
if (error)
return error;
attr->xattri_dela_state = XFS_DAS_LEAF_ADD;
out:
trace_xfs_attr_sf_addname_return(attr->xattri_dela_state, args->dp);
return error;
}
/* Compute the hash value for a user/root/secure extended attribute */
xfs_dahash_t
xfs_attr_hashname(
const uint8_t *name,
int namelen)
{
return xfs_da_hashname(name, namelen);
}
/* Compute the hash value for any extended attribute from any namespace. */
xfs_dahash_t
xfs_attr_hashval(
struct xfs_mount *mp,
unsigned int attr_flags,
const uint8_t *name,
int namelen,
const void *value,
int valuelen)
{
ASSERT(xfs_attr_check_namespace(attr_flags));
if (attr_flags & XFS_ATTR_PARENT)
return xfs_parent_hashattr(mp, name, namelen, value, valuelen);
return xfs_attr_hashname(name, namelen);
}
/*
* PPTR_REPLACE operations require the caller to set the old and new names and
* values explicitly. Update the canonical fields to the new name and value
* here now that the removal phase has finished.
*/
static void
xfs_attr_update_pptr_replace_args(
struct xfs_da_args *args)
{
ASSERT(args->new_namelen > 0);
args->name = args->new_name;
args->namelen = args->new_namelen;
args->value = args->new_value;
args->valuelen = args->new_valuelen;
xfs_attr_sethash(args);
}
/*
* Handle the state change on completion of a multi-state attr operation.
*
* If the XFS_DA_OP_REPLACE flag is set, this means the operation was the first
* modification in a attr replace operation and we still have to do the second
* state, indicated by @replace_state.
*
* We consume the XFS_DA_OP_REPLACE flag so that when we are called again on
* completion of the second half of the attr replace operation we correctly
* signal that it is done.
*/
static enum xfs_delattr_state
xfs_attr_complete_op(
struct xfs_attr_intent *attr,
enum xfs_delattr_state replace_state)
{
struct xfs_da_args *args = attr->xattri_da_args;
if (!(args->op_flags & XFS_DA_OP_REPLACE))
replace_state = XFS_DAS_DONE;
else if (xfs_attr_intent_op(attr) == XFS_ATTRI_OP_FLAGS_PPTR_REPLACE)
xfs_attr_update_pptr_replace_args(args);
args->op_flags &= ~XFS_DA_OP_REPLACE;
args->attr_filter &= ~XFS_ATTR_INCOMPLETE;
return replace_state;
}
static int
xfs_attr_leaf_addname(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
int error;
ASSERT(xfs_attr_is_leaf(args->dp));
/*
* Use the leaf buffer we may already hold locked as a result of
* a sf-to-leaf conversion.
*/
error = xfs_attr_leaf_try_add(args);
if (error == -ENOSPC) {
error = xfs_attr3_leaf_to_node(args);
if (error)
return error;
/*
* We're not in leaf format anymore, so roll the transaction and
* retry the add to the newly allocated node block.
*/
attr->xattri_dela_state = XFS_DAS_NODE_ADD;
goto out;
}
if (error)
return error;
/*
* We need to commit and roll if we need to allocate remote xattr blocks
* or perform more xattr manipulations. Otherwise there is nothing more
* to do and we can return success.
*/
if (args->rmtblkno)
attr->xattri_dela_state = XFS_DAS_LEAF_SET_RMT;
else
attr->xattri_dela_state = xfs_attr_complete_op(attr,
XFS_DAS_LEAF_REPLACE);
out:
trace_xfs_attr_leaf_addname_return(attr->xattri_dela_state, args->dp);
return error;
}
/*
* Add an entry to a node format attr tree.
*
* Note that we might still have a leaf here - xfs_attr_is_leaf() cannot tell
* the difference between leaf + remote attr blocks and a node format tree,
* so we may still end up having to convert from leaf to node format here.
*/
static int
xfs_attr_node_addname(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
int error;
error = xfs_attr_node_addname_find_attr(attr);
if (error)
return error;
error = xfs_attr_node_try_addname(attr);
if (error == -ENOSPC) {
error = xfs_attr3_leaf_to_node(args);
if (error)
return error;
/*
* No state change, we really are in node form now
* but we need the transaction rolled to continue.
*/
goto out;
}
if (error)
return error;
if (args->rmtblkno)
attr->xattri_dela_state = XFS_DAS_NODE_SET_RMT;
else
attr->xattri_dela_state = xfs_attr_complete_op(attr,
XFS_DAS_NODE_REPLACE);
out:
trace_xfs_attr_node_addname_return(attr->xattri_dela_state, args->dp);
return error;
}
static int
xfs_attr_rmtval_alloc(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
int error = 0;
/*
* 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 (attr->xattri_blkcnt > 0) {
error = xfs_attr_rmtval_set_blk(attr);
if (error)
return error;
/* Roll the transaction only if there is more to allocate. */
if (attr->xattri_blkcnt > 0)
goto out;
}
error = xfs_attr_rmtval_set_value(args);
if (error)
return error;
attr->xattri_dela_state = xfs_attr_complete_op(attr,
++attr->xattri_dela_state);
/*
* If we are not doing a rename, we've finished the operation but still
* have to clear the incomplete flag protecting the new attr from
* exposing partially initialised state if we crash during creation.
*/
if (attr->xattri_dela_state == XFS_DAS_DONE)
error = xfs_attr3_leaf_clearflag(args);
out:
trace_xfs_attr_rmtval_alloc(attr->xattri_dela_state, args->dp);
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);
}
/* Ensure the da state of an xattr deferred work item is ready to go. */
static inline void
xfs_attr_item_init_da_state(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
if (!attr->xattri_da_state)
attr->xattri_da_state = xfs_da_state_alloc(args);
else
xfs_da_state_reset(attr->xattri_da_state, 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_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
struct xfs_da_state *state;
int error;
xfs_attr_item_init_da_state(attr);
error = xfs_attr_node_lookup(args, attr->xattri_da_state);
if (error != -EEXIST)
goto out;
error = 0;
state = attr->xattri_da_state;
ASSERT(state->path.blk[state->path.active - 1].bp != NULL);
ASSERT(state->path.blk[state->path.active - 1].magic ==
XFS_ATTR_LEAF_MAGIC);
error = xfs_attr_leaf_mark_incomplete(args, state);
if (error)
goto out;
if (args->rmtblkno > 0)
error = xfs_attr_rmtval_invalidate(args);
out:
if (error) {
xfs_da_state_free(attr->xattri_da_state);
attr->xattri_da_state = NULL;
}
return error;
}
/*
* Remove the original attr we have just replaced. This is dependent on the
* original lookup and insert placing the old attr in args->blkno/args->index
* and the new attr in args->blkno2/args->index2.
*/
static int
xfs_attr_leaf_remove_attr(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
struct xfs_inode *dp = args->dp;
struct xfs_buf *bp = NULL;
int forkoff;
int error;
error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
args->blkno, &bp);
if (error)
return error;
xfs_attr3_leaf_remove(bp, args);
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;
}
/*
* Shrink an attribute from leaf to shortform. Used by the node format remove
* path when the node format collapses to a single block and so we have to check
* if it can be collapsed further.
*/
static int
xfs_attr_leaf_shrink(
struct xfs_da_args *args)
{
struct xfs_inode *dp = args->dp;
struct xfs_buf *bp;
int forkoff;
int error;
if (!xfs_attr_is_leaf(dp))
return 0;
error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 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;
}
/*
* Run the attribute operation specified in @attr.
*
* This routine is meant to function as a delayed operation and will set the
* state to XFS_DAS_DONE when the operation is complete. Calling functions will
* need to handle this, and recall the function until either an error or
* XFS_DAS_DONE is detected.
*/
int
xfs_attr_set_iter(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
int error = 0;
/* State machine switch */
next_state:
switch (attr->xattri_dela_state) {
case XFS_DAS_UNINIT:
ASSERT(0);
return -EFSCORRUPTED;
case XFS_DAS_SF_ADD:
return xfs_attr_sf_addname(attr);
case XFS_DAS_LEAF_ADD:
return xfs_attr_leaf_addname(attr);
case XFS_DAS_NODE_ADD:
return xfs_attr_node_addname(attr);
case XFS_DAS_SF_REMOVE:
error = xfs_attr_sf_removename(args);
attr->xattri_dela_state = xfs_attr_complete_op(attr,
xfs_attr_init_add_state(args));
break;
case XFS_DAS_LEAF_REMOVE:
error = xfs_attr_leaf_removename(args);
attr->xattri_dela_state = xfs_attr_complete_op(attr,
xfs_attr_init_add_state(args));
break;
case XFS_DAS_NODE_REMOVE:
error = xfs_attr_node_removename_setup(attr);
if (error == -ENOATTR &&
(args->op_flags & XFS_DA_OP_RECOVERY)) {
attr->xattri_dela_state = xfs_attr_complete_op(attr,
xfs_attr_init_add_state(args));
error = 0;
break;
}
if (error)
return error;
attr->xattri_dela_state = XFS_DAS_NODE_REMOVE_RMT;
if (args->rmtblkno == 0)
attr->xattri_dela_state++;
break;
case XFS_DAS_LEAF_SET_RMT:
case XFS_DAS_NODE_SET_RMT:
error = xfs_attr_rmtval_find_space(attr);
if (error)
return error;
attr->xattri_dela_state++;
fallthrough;
case XFS_DAS_LEAF_ALLOC_RMT:
case XFS_DAS_NODE_ALLOC_RMT:
error = xfs_attr_rmtval_alloc(attr);
if (error)
return error;
if (attr->xattri_dela_state == XFS_DAS_DONE)
break;
goto next_state;
case XFS_DAS_LEAF_REPLACE:
case XFS_DAS_NODE_REPLACE:
/*
* We must "flip" the incomplete flags on the "new" and "old"
* attribute/value pairs so that one disappears and one appears
* atomically.
*/
error = xfs_attr3_leaf_flipflags(args);
if (error)
return error;
/*
* We must commit the flag value change now to make it atomic
* and then we can start the next trans in series at REMOVE_OLD.
*/
attr->xattri_dela_state++;
break;
case XFS_DAS_LEAF_REMOVE_OLD:
case XFS_DAS_NODE_REMOVE_OLD:
/*
* If we have a remote attr, start the process of removing it
* by invalidating any cached buffers.
*
* If we don't have a remote attr, we skip the remote block
* removal state altogether with a second state increment.
*/
xfs_attr_restore_rmt_blk(args);
if (args->rmtblkno) {
error = xfs_attr_rmtval_invalidate(args);
if (error)
return error;
} else {
attr->xattri_dela_state++;
}
attr->xattri_dela_state++;
goto next_state;
case XFS_DAS_LEAF_REMOVE_RMT:
case XFS_DAS_NODE_REMOVE_RMT:
error = xfs_attr_rmtval_remove(attr);
if (error == -EAGAIN) {
error = 0;
break;
}
if (error)
return error;
/*
* We've finished removing the remote attr blocks, so commit the
* transaction and move on to removing the attr name from the
* leaf/node block. Removing the attr might require a full
* transaction reservation for btree block freeing, so we
* can't do that in the same transaction where we removed the
* remote attr blocks.
*/
attr->xattri_dela_state++;
break;
case XFS_DAS_LEAF_REMOVE_ATTR:
error = xfs_attr_leaf_remove_attr(attr);
attr->xattri_dela_state = xfs_attr_complete_op(attr,
xfs_attr_init_add_state(args));
break;
case XFS_DAS_NODE_REMOVE_ATTR:
error = xfs_attr_node_remove_attr(attr);
if (!error)
error = xfs_attr_leaf_shrink(args);
attr->xattri_dela_state = xfs_attr_complete_op(attr,
xfs_attr_init_add_state(args));
break;
default:
ASSERT(0);
break;
}
trace_xfs_attr_set_iter_return(attr->xattri_dela_state, args->dp);
return error;
}
/*
* Return EEXIST if attr is found, or ENOATTR if not
*/
static int
xfs_attr_lookup(
struct xfs_da_args *args)
{
struct xfs_inode *dp = args->dp;
struct xfs_buf *bp = NULL;
struct xfs_da_state *state;
int error;
if (!xfs_inode_hasattr(dp))
return -ENOATTR;
if (dp->i_af.if_format == XFS_DINODE_FMT_LOCAL) {
if (xfs_attr_sf_findname(args))
return -EEXIST;
return -ENOATTR;
}
/* Prerequisite for xfs_attr_is_leaf */
error = xfs_iread_extents(args->trans, args->dp, XFS_ATTR_FORK);
if (error)
return error;
if (xfs_attr_is_leaf(dp)) {
error = xfs_attr_leaf_hasname(args, &bp);
if (bp)
xfs_trans_brelse(args->trans, bp);
return error;
}
state = xfs_da_state_alloc(args);
error = xfs_attr_node_lookup(args, state);
xfs_da_state_free(state);
return error;
}
int
xfs_attr_add_fork(
struct xfs_inode *ip, /* incore inode pointer */
int size, /* space new attribute needs */
int rsvd) /* xact may use reserved blks */
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp; /* transaction pointer */
unsigned int blks; /* space reservation */
int error; /* error return value */
ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
blks = XFS_ADDAFORK_SPACE_RES(mp);
error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_addafork, blks, 0,
rsvd, &tp);
if (error)
return error;
if (xfs_inode_has_attr_fork(ip))
goto trans_cancel;
error = xfs_bmap_add_attrfork(tp, ip, size, rsvd);
if (error)
goto trans_cancel;
error = xfs_trans_commit(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
trans_cancel:
xfs_trans_cancel(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
/*
* Make a change to the xattr structure.
*
* The caller must have initialized @args, attached dquots, and must not hold
* any ILOCKs. Reserved data blocks may be used if @rsvd is set.
*
* Returns -EEXIST for XFS_ATTRUPDATE_CREATE if the name already exists.
* Returns -ENOATTR for XFS_ATTRUPDATE_REMOVE if the name does not exist.
* Returns 0 on success, or a negative errno if something else went wrong.
*/
int
xfs_attr_set(
struct xfs_da_args *args,
enum xfs_attr_update op,
bool rsvd)
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
struct xfs_trans_res tres;
int error, local;
int rmt_blks = 0;
unsigned int total = 0;
ASSERT(!args->trans);
switch (op) {
case XFS_ATTRUPDATE_UPSERT:
case XFS_ATTRUPDATE_CREATE:
case XFS_ATTRUPDATE_REPLACE:
XFS_STATS_INC(mp, xs_attr_set);
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_inode_has_attr_fork(dp) == 0) {
int sf_size = sizeof(struct xfs_attr_sf_hdr) +
xfs_attr_sf_entsize_byname(args->namelen,
args->valuelen);
error = xfs_attr_add_fork(dp, sf_size, rsvd);
if (error)
return error;
}
if (!local)
rmt_blks = xfs_attr3_rmt_blocks(mp, args->valuelen);
tres = xfs_attr_set_resv(args);
total = args->total;
break;
case XFS_ATTRUPDATE_REMOVE:
XFS_STATS_INC(mp, xs_attr_remove);
rmt_blks = xfs_attr3_max_rmt_blocks(mp);
tres = M_RES(mp)->tr_attrrm;
total = XFS_ATTRRM_SPACE_RES(mp);
break;
}
/*
* Root fork attributes can use reserved data blocks for this
* operation if necessary
*/
error = xfs_trans_alloc_inode(dp, &tres, total, 0, rsvd, &args->trans);
if (error)
return error;
if (op != XFS_ATTRUPDATE_REMOVE || xfs_inode_hasattr(dp)) {
error = xfs_iext_count_extend(args->trans, dp, XFS_ATTR_FORK,
XFS_IEXT_ATTR_MANIP_CNT(rmt_blks));
if (error)
goto out_trans_cancel;
}
error = xfs_attr_lookup(args);
switch (error) {
case -EEXIST:
if (op == XFS_ATTRUPDATE_REMOVE) {
/* if no value, we are performing a remove operation */
xfs_attr_defer_add(args, XFS_ATTR_DEFER_REMOVE);
break;
}
/* Pure create fails if the attr already exists */
if (op == XFS_ATTRUPDATE_CREATE)
goto out_trans_cancel;
xfs_attr_defer_add(args, XFS_ATTR_DEFER_REPLACE);
break;
case -ENOATTR:
/* Can't remove what isn't there. */
if (op == XFS_ATTRUPDATE_REMOVE)
goto out_trans_cancel;
/* Pure replace fails if no existing attr to replace. */
if (op == XFS_ATTRUPDATE_REPLACE)
goto out_trans_cancel;
xfs_attr_defer_add(args, XFS_ATTR_DEFER_SET);
break;
default:
goto out_trans_cancel;
}
/*
* If this is a synchronous mount, make sure that the
* transaction goes to disk before returning to the user.
*/
if (xfs_has_wsync(mp))
xfs_trans_set_sync(args->trans);
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);
args->trans = NULL;
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
*========================================================================*/
int xfs_attr_sf_totsize(struct xfs_inode *dp)
{
struct xfs_attr_sf_hdr *sf = dp->i_af.if_data;
return be16_to_cpu(sf->totsize);
}
/*
* Add a name to the shortform attribute list structure
* This is the external routine.
*/
static int
xfs_attr_shortform_addname(
struct xfs_da_args *args)
{
int newsize, forkoff;
trace_xfs_attr_sf_addname(args);
if (xfs_attr_sf_findname(args)) {
int error;
ASSERT(args->op_flags & XFS_DA_OP_REPLACE);
error = xfs_attr_sf_removename(args);
if (error)
return error;
/*
* Since we have removed the old attr, clear XFS_DA_OP_REPLACE
* so that the new attr doesn't fit in shortform format, the
* leaf format add routine won't trip over the attr not being
* around.
*/
args->op_flags &= ~XFS_DA_OP_REPLACE;
} else {
ASSERT(!(args->op_flags & XFS_DA_OP_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
*========================================================================*/
/* Save the current remote block info and clear the current pointers. */
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;
args->rmtblkno = 0;
args->rmtblkcnt = 0;
args->rmtvaluelen = 0;
}
/* 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 error;
error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, &bp);
if (error)
return error;
/*
* Look up the xattr name to set the insertion point for the new xattr.
*/
error = xfs_attr3_leaf_lookup_int(bp, args);
switch (error) {
case -ENOATTR:
if (args->op_flags & XFS_DA_OP_REPLACE)
goto out_brelse;
break;
case -EEXIST:
if (!(args->op_flags & XFS_DA_OP_REPLACE))
goto out_brelse;
trace_xfs_attr_leaf_replace(args);
/*
* Save the existing remote attr state so that the current
* values reflect the state of the new attribute we are about to
* add, not the attribute we just found and will remove later.
*/
xfs_attr_save_rmt_blk(args);
break;
case 0:
break;
default:
goto out_brelse;
}
return xfs_attr3_leaf_add(bp, args);
out_brelse:
xfs_trans_brelse(args->trans, bp);
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, args->owner, 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);
if (args->op_flags & XFS_DA_OP_RECOVERY)
return 0;
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. */
STATIC int
xfs_attr_node_lookup(
struct xfs_da_args *args,
struct xfs_da_state *state)
{
int retval, error;
/*
* Search to see if name exists, and get back a pointer to it.
*/
error = xfs_da3_node_lookup_int(state, &retval);
if (error)
return error;
return retval;
}
/*========================================================================
* External routines when attribute list size > geo->blksize
*========================================================================*/
STATIC int
xfs_attr_node_addname_find_attr(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
int error;
/*
* Search to see if name already exists, and get back a pointer
* to where it should go.
*/
xfs_attr_item_init_da_state(attr);
error = xfs_attr_node_lookup(args, attr->xattri_da_state);
switch (error) {
case -ENOATTR:
if (args->op_flags & XFS_DA_OP_REPLACE)
goto error;
break;
case -EEXIST:
if (!(args->op_flags & XFS_DA_OP_REPLACE))
goto error;
trace_xfs_attr_node_replace(args);
/*
* Save the existing remote attr state so that the current
* values reflect the state of the new attribute we are about to
* add, not the attribute we just found and will remove later.
*/
xfs_attr_save_rmt_blk(args);
break;
case 0:
break;
default:
goto error;
}
return 0;
error:
if (attr->xattri_da_state) {
xfs_da_state_free(attr->xattri_da_state);
attr->xattri_da_state = NULL;
}
return error;
}
/*
* 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).
*/
static int
xfs_attr_node_try_addname(
struct xfs_attr_intent *attr)
{
struct xfs_da_state *state = attr->xattri_da_state;
struct xfs_da_state_blk *blk;
int error;
trace_xfs_attr_node_addname(state->args);
blk = &state->path.blk[state->path.active-1];
ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
error = xfs_attr3_leaf_add(blk->bp, state->args);
if (error == -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. Let the caller deal with this.
*/
goto out;
}
/*
* 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;
} else {
/*
* Addition succeeded, update Btree hashvals.
*/
xfs_da3_fixhashpath(state, &state->path);
}
out:
xfs_da_state_free(state);
attr->xattri_da_state = NULL;
return error;
}
static int
xfs_attr_node_removename(
struct xfs_da_args *args,
struct xfs_da_state *state)
{
struct xfs_da_state_blk *blk;
int retval;
/*
* 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);
return retval;
}
static int
xfs_attr_node_remove_attr(
struct xfs_attr_intent *attr)
{
struct xfs_da_args *args = attr->xattri_da_args;
struct xfs_da_state *state = xfs_da_state_alloc(args);
int retval = 0;
int error = 0;
/*
* The attr we are removing has already been marked incomplete, so
* we need to set the filter appropriately to re-find the "old"
* attribute entry after any split ops.
*/
args->attr_filter |= XFS_ATTR_INCOMPLETE;
error = xfs_da3_node_lookup_int(state, &retval);
if (error)
goto out;
error = xfs_attr_node_removename(args, state);
/*
* 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:
xfs_da_state_free(state);
if (error)
return error;
return retval;
}
/*
* 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.
*/
state = xfs_da_state_alloc(args);
error = xfs_attr_node_lookup(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; 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 error;
}
/* Enforce that there is at most one namespace bit per attr. */
inline bool xfs_attr_check_namespace(unsigned int attr_flags)
{
return hweight32(attr_flags & XFS_ATTR_NSP_ONDISK_MASK) < 2;
}
/* Returns true if the attribute entry name is valid. */
bool
xfs_attr_namecheck(
unsigned int attr_flags,
const void *name,
size_t length)
{
/* Only one namespace bit allowed. */
if (!xfs_attr_check_namespace(attr_flags))
return false;
/*
* MAXNAMELEN includes the trailing null, but (name/length) leave it
* out, so use >= for the length check.
*/
if (length >= MAXNAMELEN)
return false;
/* Parent pointers have their own validation. */
if (attr_flags & XFS_ATTR_PARENT)
return xfs_parent_namecheck(attr_flags, name, length);
/* There shouldn't be any nulls here */
return !memchr(name, 0, length);
}
int __init
xfs_attr_intent_init_cache(void)
{
xfs_attr_intent_cache = kmem_cache_create("xfs_attr_intent",
sizeof(struct xfs_attr_intent),
0, 0, NULL);
return xfs_attr_intent_cache != NULL ? 0 : -ENOMEM;
}
void
xfs_attr_intent_destroy_cache(void)
{
kmem_cache_destroy(xfs_attr_intent_cache);
xfs_attr_intent_cache = NULL;
}
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