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gerrit-public.fairphone.software / kernel / msm-4.9 / b31b05cf629574d47b324bb52128ed1b199faccd / . / fs / xfs / libxfs / xfs_inode_fork.c
blob: 6a00f7fed69d712ab7d15790f7f527c45f61c767 [file] [log] [blame]
/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/log2.h>
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_inum.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_inode_item.h"
#include "xfs_bmap_btree.h"
#include "xfs_bmap.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
kmem_zone_t *xfs_ifork_zone;
STATIC int xfs_iformat_local(xfs_inode_t *, xfs_dinode_t *, int, int);
STATIC int xfs_iformat_extents(xfs_inode_t *, xfs_dinode_t *, int);
STATIC int xfs_iformat_btree(xfs_inode_t *, xfs_dinode_t *, int);
#ifdef DEBUG
/*
* Make sure that the extents in the given memory buffer
* are valid.
*/
void
xfs_validate_extents(
xfs_ifork_t *ifp,
int nrecs,
xfs_exntfmt_t fmt)
{
xfs_bmbt_irec_t irec;
xfs_bmbt_rec_host_t rec;
int i;
for (i = 0; i < nrecs; i++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
rec.l0 = get_unaligned(&ep->l0);
rec.l1 = get_unaligned(&ep->l1);
xfs_bmbt_get_all(&rec, &irec);
if (fmt == XFS_EXTFMT_NOSTATE)
ASSERT(irec.br_state == XFS_EXT_NORM);
}
}
#else /* DEBUG */
#define xfs_validate_extents(ifp, nrecs, fmt)
#endif /* DEBUG */
/*
* Move inode type and inode format specific information from the
* on-disk inode to the in-core inode. For fifos, devs, and sockets
* this means set if_rdev to the proper value. For files, directories,
* and symlinks this means to bring in the in-line data or extent
* pointers. For a file in B-tree format, only the root is immediately
* brought in-core. The rest will be in-lined in if_extents when it
* is first referenced (see xfs_iread_extents()).
*/
int
xfs_iformat_fork(
xfs_inode_t *ip,
xfs_dinode_t *dip)
{
xfs_attr_shortform_t *atp;
int size;
int error = 0;
xfs_fsize_t di_size;
if (unlikely(be32_to_cpu(dip->di_nextents) +
be16_to_cpu(dip->di_anextents) >
be64_to_cpu(dip->di_nblocks))) {
xfs_warn(ip->i_mount,
"corrupt dinode %Lu, extent total = %d, nblocks = %Lu.",
(unsigned long long)ip->i_ino,
(int)(be32_to_cpu(dip->di_nextents) +
be16_to_cpu(dip->di_anextents)),
(unsigned long long)
be64_to_cpu(dip->di_nblocks));
XFS_CORRUPTION_ERROR("xfs_iformat(1)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
if (unlikely(dip->di_forkoff > ip->i_mount->m_sb.sb_inodesize)) {
xfs_warn(ip->i_mount, "corrupt dinode %Lu, forkoff = 0x%x.",
(unsigned long long)ip->i_ino,
dip->di_forkoff);
XFS_CORRUPTION_ERROR("xfs_iformat(2)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
if (unlikely((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) &&
!ip->i_mount->m_rtdev_targp)) {
xfs_warn(ip->i_mount,
"corrupt dinode %Lu, has realtime flag set.",
ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat(realtime)",
XFS_ERRLEVEL_LOW, ip->i_mount, dip);
return -EFSCORRUPTED;
}
switch (ip->i_d.di_mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
if (unlikely(dip->di_format != XFS_DINODE_FMT_DEV)) {
XFS_CORRUPTION_ERROR("xfs_iformat(3)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
ip->i_d.di_size = 0;
ip->i_df.if_u2.if_rdev = xfs_dinode_get_rdev(dip);
break;
case S_IFREG:
case S_IFLNK:
case S_IFDIR:
switch (dip->di_format) {
case XFS_DINODE_FMT_LOCAL:
/*
* no local regular files yet
*/
if (unlikely(S_ISREG(be16_to_cpu(dip->di_mode)))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (local format for regular file).",
(unsigned long long) ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat(4)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
di_size = be64_to_cpu(dip->di_size);
if (unlikely(di_size < 0 ||
di_size > XFS_DFORK_DSIZE(dip, ip->i_mount))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad size %Ld for local inode).",
(unsigned long long) ip->i_ino,
(long long) di_size);
XFS_CORRUPTION_ERROR("xfs_iformat(5)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
size = (int)di_size;
error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, size);
break;
case XFS_DINODE_FMT_EXTENTS:
error = xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
break;
case XFS_DINODE_FMT_BTREE:
error = xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
break;
default:
XFS_ERROR_REPORT("xfs_iformat(6)", XFS_ERRLEVEL_LOW,
ip->i_mount);
return -EFSCORRUPTED;
}
break;
default:
XFS_ERROR_REPORT("xfs_iformat(7)", XFS_ERRLEVEL_LOW, ip->i_mount);
return -EFSCORRUPTED;
}
if (error) {
return error;
}
if (!XFS_DFORK_Q(dip))
return 0;
ASSERT(ip->i_afp == NULL);
ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP | KM_NOFS);
switch (dip->di_aformat) {
case XFS_DINODE_FMT_LOCAL:
atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR(dip);
size = be16_to_cpu(atp->hdr.totsize);
if (unlikely(size < sizeof(struct xfs_attr_sf_hdr))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad attr fork size %Ld).",
(unsigned long long) ip->i_ino,
(long long) size);
XFS_CORRUPTION_ERROR("xfs_iformat(8)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);
break;
case XFS_DINODE_FMT_EXTENTS:
error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
break;
case XFS_DINODE_FMT_BTREE:
error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
break;
default:
error = -EFSCORRUPTED;
break;
}
if (error) {
kmem_zone_free(xfs_ifork_zone, ip->i_afp);
ip->i_afp = NULL;
xfs_idestroy_fork(ip, XFS_DATA_FORK);
}
return error;
}
/*
* The file is in-lined in the on-disk inode.
* If it fits into if_inline_data, then copy
* it there, otherwise allocate a buffer for it
* and copy the data there. Either way, set
* if_data to point at the data.
* If we allocate a buffer for the data, make
* sure that its size is a multiple of 4 and
* record the real size in i_real_bytes.
*/
STATIC int
xfs_iformat_local(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork,
int size)
{
xfs_ifork_t *ifp;
int real_size;
/*
* If the size is unreasonable, then something
* is wrong and we just bail out rather than crash in
* kmem_alloc() or memcpy() below.
*/
if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad size %d for local fork, size = %d).",
(unsigned long long) ip->i_ino, size,
XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
XFS_CORRUPTION_ERROR("xfs_iformat_local", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
ifp = XFS_IFORK_PTR(ip, whichfork);
real_size = 0;
if (size == 0)
ifp->if_u1.if_data = NULL;
else if (size <= sizeof(ifp->if_u2.if_inline_data))
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
else {
real_size = roundup(size, 4);
ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP | KM_NOFS);
}
ifp->if_bytes = size;
ifp->if_real_bytes = real_size;
if (size)
memcpy(ifp->if_u1.if_data, XFS_DFORK_PTR(dip, whichfork), size);
ifp->if_flags &= ~XFS_IFEXTENTS;
ifp->if_flags |= XFS_IFINLINE;
return 0;
}
/*
* The file consists of a set of extents all
* of which fit into the on-disk inode.
* If there are few enough extents to fit into
* the if_inline_ext, then copy them there.
* Otherwise allocate a buffer for them and copy
* them into it. Either way, set if_extents
* to point at the extents.
*/
STATIC int
xfs_iformat_extents(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork)
{
xfs_bmbt_rec_t *dp;
xfs_ifork_t *ifp;
int nex;
int size;
int i;
ifp = XFS_IFORK_PTR(ip, whichfork);
nex = XFS_DFORK_NEXTENTS(dip, whichfork);
size = nex * (uint)sizeof(xfs_bmbt_rec_t);
/*
* If the number of extents is unreasonable, then something
* is wrong and we just bail out rather than crash in
* kmem_alloc() or memcpy() below.
*/
if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).",
(unsigned long long) ip->i_ino, nex);
XFS_CORRUPTION_ERROR("xfs_iformat_extents(1)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return -EFSCORRUPTED;
}
ifp->if_real_bytes = 0;
if (nex == 0)
ifp->if_u1.if_extents = NULL;
else if (nex <= XFS_INLINE_EXTS)
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
else
xfs_iext_add(ifp, 0, nex);
ifp->if_bytes = size;
if (size) {
dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
xfs_validate_extents(ifp, nex, XFS_EXTFMT_INODE(ip));
for (i = 0; i < nex; i++, dp++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
ep->l0 = get_unaligned_be64(&dp->l0);
ep->l1 = get_unaligned_be64(&dp->l1);
}
XFS_BMAP_TRACE_EXLIST(ip, nex, whichfork);
if (whichfork != XFS_DATA_FORK ||
XFS_EXTFMT_INODE(ip) == XFS_EXTFMT_NOSTATE)
if (unlikely(xfs_check_nostate_extents(
ifp, 0, nex))) {
XFS_ERROR_REPORT("xfs_iformat_extents(2)",
XFS_ERRLEVEL_LOW,
ip->i_mount);
return -EFSCORRUPTED;
}
}
ifp->if_flags |= XFS_IFEXTENTS;
return 0;
}
/*
* The file has too many extents to fit into
* the inode, so they are in B-tree format.
* Allocate a buffer for the root of the B-tree
* and copy the root into it. The i_extents
* field will remain NULL until all of the
* extents are read in (when they are needed).
*/
STATIC int
xfs_iformat_btree(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork)
{
struct xfs_mount *mp = ip->i_mount;
xfs_bmdr_block_t *dfp;
xfs_ifork_t *ifp;
/* REFERENCED */
int nrecs;
int size;
ifp = XFS_IFORK_PTR(ip, whichfork);
dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
size = XFS_BMAP_BROOT_SPACE(mp, dfp);
nrecs = be16_to_cpu(dfp->bb_numrecs);
/*
* blow out if -- fork has less extents than can fit in
* fork (fork shouldn't be a btree format), root btree
* block has more records than can fit into the fork,
* or the number of extents is greater than the number of
* blocks.
*/
if (unlikely(XFS_IFORK_NEXTENTS(ip, whichfork) <=
XFS_IFORK_MAXEXT(ip, whichfork) ||
XFS_BMDR_SPACE_CALC(nrecs) >
XFS_DFORK_SIZE(dip, mp, whichfork) ||
XFS_IFORK_NEXTENTS(ip, whichfork) > ip->i_d.di_nblocks)) {
xfs_warn(mp, "corrupt inode %Lu (btree).",
(unsigned long long) ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat_btree", XFS_ERRLEVEL_LOW,
mp, dip);
return -EFSCORRUPTED;
}
ifp->if_broot_bytes = size;
ifp->if_broot = kmem_alloc(size, KM_SLEEP | KM_NOFS);
ASSERT(ifp->if_broot != NULL);
/*
* Copy and convert from the on-disk structure
* to the in-memory structure.
*/
xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
ifp->if_broot, size);
ifp->if_flags &= ~XFS_IFEXTENTS;
ifp->if_flags |= XFS_IFBROOT;
return 0;
}
/*
* Read in extents from a btree-format inode.
* Allocate and fill in if_extents. Real work is done in xfs_bmap.c.
*/
int
xfs_iread_extents(
xfs_trans_t *tp,
xfs_inode_t *ip,
int whichfork)
{
int error;
xfs_ifork_t *ifp;
xfs_extnum_t nextents;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
XFS_ERROR_REPORT("xfs_iread_extents", XFS_ERRLEVEL_LOW,
ip->i_mount);
return -EFSCORRUPTED;
}
nextents = XFS_IFORK_NEXTENTS(ip, whichfork);
ifp = XFS_IFORK_PTR(ip, whichfork);
/*
* We know that the size is valid (it's checked in iformat_btree)
*/
ifp->if_bytes = ifp->if_real_bytes = 0;
ifp->if_flags |= XFS_IFEXTENTS;
xfs_iext_add(ifp, 0, nextents);
error = xfs_bmap_read_extents(tp, ip, whichfork);
if (error) {
xfs_iext_destroy(ifp);
ifp->if_flags &= ~XFS_IFEXTENTS;
return error;
}
xfs_validate_extents(ifp, nextents, XFS_EXTFMT_INODE(ip));
return 0;
}
/*
* Reallocate the space for if_broot based on the number of records
* being added or deleted as indicated in rec_diff. Move the records
* and pointers in if_broot to fit the new size. When shrinking this
* will eliminate holes between the records and pointers created by
* the caller. When growing this will create holes to be filled in
* by the caller.
*
* The caller must not request to add more records than would fit in
* the on-disk inode root. If the if_broot is currently NULL, then
* if we are adding records, one will be allocated. The caller must also
* not request that the number of records go below zero, although
* it can go to zero.
*
* ip -- the inode whose if_broot area is changing
* ext_diff -- the change in the number of records, positive or negative,
* requested for the if_broot array.
*/
void
xfs_iroot_realloc(
xfs_inode_t *ip,
int rec_diff,
int whichfork)
{
struct xfs_mount *mp = ip->i_mount;
int cur_max;
xfs_ifork_t *ifp;
struct xfs_btree_block *new_broot;
int new_max;
size_t new_size;
char *np;
char *op;
/*
* Handle the degenerate case quietly.
*/
if (rec_diff == 0) {
return;
}
ifp = XFS_IFORK_PTR(ip, whichfork);
if (rec_diff > 0) {
/*
* If there wasn't any memory allocated before, just
* allocate it now and get out.
*/
if (ifp->if_broot_bytes == 0) {
new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, rec_diff);
ifp->if_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
ifp->if_broot_bytes = (int)new_size;
return;
}
/*
* If there is already an existing if_broot, then we need
* to realloc() it and shift the pointers to their new
* location. The records don't change location because
* they are kept butted up against the btree block header.
*/
cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
new_max = cur_max + rec_diff;
new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
ifp->if_broot = kmem_realloc(ifp->if_broot, new_size,
XFS_BMAP_BROOT_SPACE_CALC(mp, cur_max),
KM_SLEEP | KM_NOFS);
op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
ifp->if_broot_bytes);
np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
(int)new_size);
ifp->if_broot_bytes = (int)new_size;
ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
XFS_IFORK_SIZE(ip, whichfork));
memmove(np, op, cur_max * (uint)sizeof(xfs_fsblock_t));
return;
}
/*
* rec_diff is less than 0. In this case, we are shrinking the
* if_broot buffer. It must already exist. If we go to zero
* records, just get rid of the root and clear the status bit.
*/
ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
new_max = cur_max + rec_diff;
ASSERT(new_max >= 0);
if (new_max > 0)
new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
else
new_size = 0;
if (new_size > 0) {
new_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
/*
* First copy over the btree block header.
*/
memcpy(new_broot, ifp->if_broot,
XFS_BMBT_BLOCK_LEN(ip->i_mount));
} else {
new_broot = NULL;
ifp->if_flags &= ~XFS_IFBROOT;
}
/*
* Only copy the records and pointers if there are any.
*/
if (new_max > 0) {
/*
* First copy the records.
*/
op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1);
np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1);
memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));
/*
* Then copy the pointers.
*/
op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
ifp->if_broot_bytes);
np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1,
(int)new_size);
memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t));
}
kmem_free(ifp->if_broot);
ifp->if_broot = new_broot;
ifp->if_broot_bytes = (int)new_size;
if (ifp->if_broot)
ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
XFS_IFORK_SIZE(ip, whichfork));
return;
}
/*
* This is called when the amount of space needed for if_data
* is increased or decreased. The change in size is indicated by
* the number of bytes that need to be added or deleted in the
* byte_diff parameter.
*
* If the amount of space needed has decreased below the size of the
* inline buffer, then switch to using the inline buffer. Otherwise,
* use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
* to what is needed.
*
* ip -- the inode whose if_data area is changing
* byte_diff -- the change in the number of bytes, positive or negative,
* requested for the if_data array.
*/
void
xfs_idata_realloc(
xfs_inode_t *ip,
int byte_diff,
int whichfork)
{
xfs_ifork_t *ifp;
int new_size;
int real_size;
if (byte_diff == 0) {
return;
}
ifp = XFS_IFORK_PTR(ip, whichfork);
new_size = (int)ifp->if_bytes + byte_diff;
ASSERT(new_size >= 0);
if (new_size == 0) {
if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
kmem_free(ifp->if_u1.if_data);
}
ifp->if_u1.if_data = NULL;
real_size = 0;
} else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) {
/*
* If the valid extents/data can fit in if_inline_ext/data,
* copy them from the malloc'd vector and free it.
*/
if (ifp->if_u1.if_data == NULL) {
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
ASSERT(ifp->if_real_bytes != 0);
memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data,
new_size);
kmem_free(ifp->if_u1.if_data);
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
}
real_size = 0;
} else {
/*
* Stuck with malloc/realloc.
* For inline data, the underlying buffer must be
* a multiple of 4 bytes in size so that it can be
* logged and stay on word boundaries. We enforce
* that here.
*/
real_size = roundup(new_size, 4);
if (ifp->if_u1.if_data == NULL) {
ASSERT(ifp->if_real_bytes == 0);
ifp->if_u1.if_data = kmem_alloc(real_size,
KM_SLEEP | KM_NOFS);
} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
/*
* Only do the realloc if the underlying size
* is really changing.
*/
if (ifp->if_real_bytes != real_size) {
ifp->if_u1.if_data =
kmem_realloc(ifp->if_u1.if_data,
real_size,
ifp->if_real_bytes,
KM_SLEEP | KM_NOFS);
}
} else {
ASSERT(ifp->if_real_bytes == 0);
ifp->if_u1.if_data = kmem_alloc(real_size,
KM_SLEEP | KM_NOFS);
memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data,
ifp->if_bytes);
}
}
ifp->if_real_bytes = real_size;
ifp->if_bytes = new_size;
ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
}
void
xfs_idestroy_fork(
xfs_inode_t *ip,
int whichfork)
{
xfs_ifork_t *ifp;
ifp = XFS_IFORK_PTR(ip, whichfork);
if (ifp->if_broot != NULL) {
kmem_free(ifp->if_broot);
ifp->if_broot = NULL;
}
/*
* If the format is local, then we can't have an extents
* array so just look for an inline data array. If we're
* not local then we may or may not have an extents list,
* so check and free it up if we do.
*/
if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) &&
(ifp->if_u1.if_data != NULL)) {
ASSERT(ifp->if_real_bytes != 0);
kmem_free(ifp->if_u1.if_data);
ifp->if_u1.if_data = NULL;
ifp->if_real_bytes = 0;
}
} else if ((ifp->if_flags & XFS_IFEXTENTS) &&
((ifp->if_flags & XFS_IFEXTIREC) ||
((ifp->if_u1.if_extents != NULL) &&
(ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)))) {
ASSERT(ifp->if_real_bytes != 0);
xfs_iext_destroy(ifp);
}
ASSERT(ifp->if_u1.if_extents == NULL ||
ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext);
ASSERT(ifp->if_real_bytes == 0);
if (whichfork == XFS_ATTR_FORK) {
kmem_zone_free(xfs_ifork_zone, ip->i_afp);
ip->i_afp = NULL;
}
}
/*
* Convert in-core extents to on-disk form
*
* For either the data or attr fork in extent format, we need to endian convert
* the in-core extent as we place them into the on-disk inode.
*
* In the case of the data fork, the in-core and on-disk fork sizes can be
* different due to delayed allocation extents. We only copy on-disk extents
* here, so callers must always use the physical fork size to determine the
* size of the buffer passed to this routine. We will return the size actually
* used.
*/
int
xfs_iextents_copy(
xfs_inode_t *ip,
xfs_bmbt_rec_t *dp,
int whichfork)
{
int copied;
int i;
xfs_ifork_t *ifp;
int nrecs;
xfs_fsblock_t start_block;
ifp = XFS_IFORK_PTR(ip, whichfork);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(ifp->if_bytes > 0);
nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
XFS_BMAP_TRACE_EXLIST(ip, nrecs, whichfork);
ASSERT(nrecs > 0);
/*
* There are some delayed allocation extents in the
* inode, so copy the extents one at a time and skip
* the delayed ones. There must be at least one
* non-delayed extent.
*/
copied = 0;
for (i = 0; i < nrecs; i++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
start_block = xfs_bmbt_get_startblock(ep);
if (isnullstartblock(start_block)) {
/*
* It's a delayed allocation extent, so skip it.
*/
continue;
}
/* Translate to on disk format */
put_unaligned_be64(ep->l0, &dp->l0);
put_unaligned_be64(ep->l1, &dp->l1);
dp++;
copied++;
}
ASSERT(copied != 0);
xfs_validate_extents(ifp, copied, XFS_EXTFMT_INODE(ip));
return (copied * (uint)sizeof(xfs_bmbt_rec_t));
}
/*
* Each of the following cases stores data into the same region
* of the on-disk inode, so only one of them can be valid at
* any given time. While it is possible to have conflicting formats
* and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
* in EXTENTS format, this can only happen when the fork has
* changed formats after being modified but before being flushed.
* In these cases, the format always takes precedence, because the
* format indicates the current state of the fork.
*/
void
xfs_iflush_fork(
xfs_inode_t *ip,
xfs_dinode_t *dip,
xfs_inode_log_item_t *iip,
int whichfork)
{
char *cp;
xfs_ifork_t *ifp;
xfs_mount_t *mp;
static const short brootflag[2] =
{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
static const short dataflag[2] =
{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
static const short extflag[2] =
{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
if (!iip)
return;
ifp = XFS_IFORK_PTR(ip, whichfork);
/*
* This can happen if we gave up in iformat in an error path,
* for the attribute fork.
*/
if (!ifp) {
ASSERT(whichfork == XFS_ATTR_FORK);
return;
}
cp = XFS_DFORK_PTR(dip, whichfork);
mp = ip->i_mount;
switch (XFS_IFORK_FORMAT(ip, whichfork)) {
case XFS_DINODE_FMT_LOCAL:
if ((iip->ili_fields & dataflag[whichfork]) &&
(ifp->if_bytes > 0)) {
ASSERT(ifp->if_u1.if_data != NULL);
ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
}
break;
case XFS_DINODE_FMT_EXTENTS:
ASSERT((ifp->if_flags & XFS_IFEXTENTS) ||
!(iip->ili_fields & extflag[whichfork]));
if ((iip->ili_fields & extflag[whichfork]) &&
(ifp->if_bytes > 0)) {
ASSERT(xfs_iext_get_ext(ifp, 0));
ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0);
(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
whichfork);
}
break;
case XFS_DINODE_FMT_BTREE:
if ((iip->ili_fields & brootflag[whichfork]) &&
(ifp->if_broot_bytes > 0)) {
ASSERT(ifp->if_broot != NULL);
ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <=
XFS_IFORK_SIZE(ip, whichfork));
xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
(xfs_bmdr_block_t *)cp,
XFS_DFORK_SIZE(dip, mp, whichfork));
}
break;
case XFS_DINODE_FMT_DEV:
if (iip->ili_fields & XFS_ILOG_DEV) {
ASSERT(whichfork == XFS_DATA_FORK);
xfs_dinode_put_rdev(dip, ip->i_df.if_u2.if_rdev);
}
break;
case XFS_DINODE_FMT_UUID:
if (iip->ili_fields & XFS_ILOG_UUID) {
ASSERT(whichfork == XFS_DATA_FORK);
memcpy(XFS_DFORK_DPTR(dip),
&ip->i_df.if_u2.if_uuid,
sizeof(uuid_t));
}
break;
default:
ASSERT(0);
break;
}
}
/*
* Return a pointer to the extent record at file index idx.
*/
xfs_bmbt_rec_host_t *
xfs_iext_get_ext(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx) /* index of target extent */
{
ASSERT(idx >= 0);
ASSERT(idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
if ((ifp->if_flags & XFS_IFEXTIREC) && (idx == 0)) {
return ifp->if_u1.if_ext_irec->er_extbuf;
} else if (ifp->if_flags & XFS_IFEXTIREC) {
xfs_ext_irec_t *erp; /* irec pointer */
int erp_idx = 0; /* irec index */
xfs_extnum_t page_idx = idx; /* ext index in target list */
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0);
return &erp->er_extbuf[page_idx];
} else if (ifp->if_bytes) {
return &ifp->if_u1.if_extents[idx];
} else {
return NULL;
}
}
/*
* Insert new item(s) into the extent records for incore inode
* fork 'ifp'. 'count' new items are inserted at index 'idx'.
*/
void
xfs_iext_insert(
xfs_inode_t *ip, /* incore inode pointer */
xfs_extnum_t idx, /* starting index of new items */
xfs_extnum_t count, /* number of inserted items */
xfs_bmbt_irec_t *new, /* items to insert */
int state) /* type of extent conversion */
{
xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
xfs_extnum_t i; /* extent record index */
trace_xfs_iext_insert(ip, idx, new, state, _RET_IP_);
ASSERT(ifp->if_flags & XFS_IFEXTENTS);
xfs_iext_add(ifp, idx, count);
for (i = idx; i < idx + count; i++, new++)
xfs_bmbt_set_all(xfs_iext_get_ext(ifp, i), new);
}
/*
* This is called when the amount of space required for incore file
* extents needs to be increased. The ext_diff parameter stores the
* number of new extents being added and the idx parameter contains
* the extent index where the new extents will be added. If the new
* extents are being appended, then we just need to (re)allocate and
* initialize the space. Otherwise, if the new extents are being
* inserted into the middle of the existing entries, a bit more work
* is required to make room for the new extents to be inserted. The
* caller is responsible for filling in the new extent entries upon
* return.
*/
void
xfs_iext_add(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin adding exts */
int ext_diff) /* number of extents to add */
{
int byte_diff; /* new bytes being added */
int new_size; /* size of extents after adding */
xfs_extnum_t nextents; /* number of extents in file */
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT((idx >= 0) && (idx <= nextents));
byte_diff = ext_diff * sizeof(xfs_bmbt_rec_t);
new_size = ifp->if_bytes + byte_diff;
/*
* If the new number of extents (nextents + ext_diff)
* fits inside the inode, then continue to use the inline
* extent buffer.
*/
if (nextents + ext_diff <= XFS_INLINE_EXTS) {
if (idx < nextents) {
memmove(&ifp->if_u2.if_inline_ext[idx + ext_diff],
&ifp->if_u2.if_inline_ext[idx],
(nextents - idx) * sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u2.if_inline_ext[idx], 0, byte_diff);
}
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
ifp->if_real_bytes = 0;
}
/*
* Otherwise use a linear (direct) extent list.
* If the extents are currently inside the inode,
* xfs_iext_realloc_direct will switch us from
* inline to direct extent allocation mode.
*/
else if (nextents + ext_diff <= XFS_LINEAR_EXTS) {
xfs_iext_realloc_direct(ifp, new_size);
if (idx < nextents) {
memmove(&ifp->if_u1.if_extents[idx + ext_diff],
&ifp->if_u1.if_extents[idx],
(nextents - idx) * sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u1.if_extents[idx], 0, byte_diff);
}
}
/* Indirection array */
else {
xfs_ext_irec_t *erp;
int erp_idx = 0;
int page_idx = idx;
ASSERT(nextents + ext_diff > XFS_LINEAR_EXTS);
if (ifp->if_flags & XFS_IFEXTIREC) {
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 1);
} else {
xfs_iext_irec_init(ifp);
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = ifp->if_u1.if_ext_irec;
}
/* Extents fit in target extent page */
if (erp && erp->er_extcount + ext_diff <= XFS_LINEAR_EXTS) {
if (page_idx < erp->er_extcount) {
memmove(&erp->er_extbuf[page_idx + ext_diff],
&erp->er_extbuf[page_idx],
(erp->er_extcount - page_idx) *
sizeof(xfs_bmbt_rec_t));
memset(&erp->er_extbuf[page_idx], 0, byte_diff);
}
erp->er_extcount += ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
}
/* Insert a new extent page */
else if (erp) {
xfs_iext_add_indirect_multi(ifp,
erp_idx, page_idx, ext_diff);
}
/*
* If extent(s) are being appended to the last page in
* the indirection array and the new extent(s) don't fit
* in the page, then erp is NULL and erp_idx is set to
* the next index needed in the indirection array.
*/
else {
uint count = ext_diff;
while (count) {
erp = xfs_iext_irec_new(ifp, erp_idx);
erp->er_extcount = min(count, XFS_LINEAR_EXTS);
count -= erp->er_extcount;
if (count)
erp_idx++;
}
}
}
ifp->if_bytes = new_size;
}
/*
* This is called when incore extents are being added to the indirection
* array and the new extents do not fit in the target extent list. The
* erp_idx parameter contains the irec index for the target extent list
* in the indirection array, and the idx parameter contains the extent
* index within the list. The number of extents being added is stored
* in the count parameter.
*
* |-------| |-------|
* | | | | idx - number of extents before idx
* | idx | | count |
* | | | | count - number of extents being inserted at idx
* |-------| |-------|
* | count | | nex2 | nex2 - number of extents after idx + count
* |-------| |-------|
*/
void
xfs_iext_add_indirect_multi(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx, /* target extent irec index */
xfs_extnum_t idx, /* index within target list */
int count) /* new extents being added */
{
int byte_diff; /* new bytes being added */
xfs_ext_irec_t *erp; /* pointer to irec entry */
xfs_extnum_t ext_diff; /* number of extents to add */
xfs_extnum_t ext_cnt; /* new extents still needed */
xfs_extnum_t nex2; /* extents after idx + count */
xfs_bmbt_rec_t *nex2_ep = NULL; /* temp list for nex2 extents */
int nlists; /* number of irec's (lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = &ifp->if_u1.if_ext_irec[erp_idx];
nex2 = erp->er_extcount - idx;
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
/*
* Save second part of target extent list
* (all extents past */
if (nex2) {
byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
nex2_ep = (xfs_bmbt_rec_t *) kmem_alloc(byte_diff, KM_NOFS);
memmove(nex2_ep, &erp->er_extbuf[idx], byte_diff);
erp->er_extcount -= nex2;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -nex2);
memset(&erp->er_extbuf[idx], 0, byte_diff);
}
/*
* Add the new extents to the end of the target
* list, then allocate new irec record(s) and
* extent buffer(s) as needed to store the rest
* of the new extents.
*/
ext_cnt = count;
ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS - erp->er_extcount);
if (ext_diff) {
erp->er_extcount += ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
ext_cnt -= ext_diff;
}
while (ext_cnt) {
erp_idx++;
erp = xfs_iext_irec_new(ifp, erp_idx);
ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS);
erp->er_extcount = ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
ext_cnt -= ext_diff;
}
/* Add nex2 extents back to indirection array */
if (nex2) {
xfs_extnum_t ext_avail;
int i;
byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
ext_avail = XFS_LINEAR_EXTS - erp->er_extcount;
i = 0;
/*
* If nex2 extents fit in the current page, append
* nex2_ep after the new extents.
*/
if (nex2 <= ext_avail) {
i = erp->er_extcount;
}
/*
* Otherwise, check if space is available in the
* next page.
*/
else if ((erp_idx < nlists - 1) &&
(nex2 <= (ext_avail = XFS_LINEAR_EXTS -
ifp->if_u1.if_ext_irec[erp_idx+1].er_extcount))) {
erp_idx++;
erp++;
/* Create a hole for nex2 extents */
memmove(&erp->er_extbuf[nex2], erp->er_extbuf,
erp->er_extcount * sizeof(xfs_bmbt_rec_t));
}
/*
* Final choice, create a new extent page for
* nex2 extents.
*/
else {
erp_idx++;
erp = xfs_iext_irec_new(ifp, erp_idx);
}
memmove(&erp->er_extbuf[i], nex2_ep, byte_diff);
kmem_free(nex2_ep);
erp->er_extcount += nex2;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, nex2);
}
}
/*
* This is called when the amount of space required for incore file
* extents needs to be decreased. The ext_diff parameter stores the
* number of extents to be removed and the idx parameter contains
* the extent index where the extents will be removed from.
*
* If the amount of space needed has decreased below the linear
* limit, XFS_IEXT_BUFSZ, then switch to using the contiguous
* extent array. Otherwise, use kmem_realloc() to adjust the
* size to what is needed.
*/
void
xfs_iext_remove(
xfs_inode_t *ip, /* incore inode pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff, /* number of extents to remove */
int state) /* type of extent conversion */
{
xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
xfs_extnum_t nextents; /* number of extents in file */
int new_size; /* size of extents after removal */
trace_xfs_iext_remove(ip, idx, state, _RET_IP_);
ASSERT(ext_diff > 0);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
new_size = (nextents - ext_diff) * sizeof(xfs_bmbt_rec_t);
if (new_size == 0) {
xfs_iext_destroy(ifp);
} else if (ifp->if_flags & XFS_IFEXTIREC) {
xfs_iext_remove_indirect(ifp, idx, ext_diff);
} else if (ifp->if_real_bytes) {
xfs_iext_remove_direct(ifp, idx, ext_diff);
} else {
xfs_iext_remove_inline(ifp, idx, ext_diff);
}
ifp->if_bytes = new_size;
}
/*
* This removes ext_diff extents from the inline buffer, beginning
* at extent index idx.
*/
void
xfs_iext_remove_inline(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff) /* number of extents to remove */
{
int nextents; /* number of extents in file */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
ASSERT(idx < XFS_INLINE_EXTS);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(((nextents - ext_diff) > 0) &&
(nextents - ext_diff) < XFS_INLINE_EXTS);
if (idx + ext_diff < nextents) {
memmove(&ifp->if_u2.if_inline_ext[idx],
&ifp->if_u2.if_inline_ext[idx + ext_diff],
(nextents - (idx + ext_diff)) *
sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u2.if_inline_ext[nextents - ext_diff],
0, ext_diff * sizeof(xfs_bmbt_rec_t));
} else {
memset(&ifp->if_u2.if_inline_ext[idx], 0,
ext_diff * sizeof(xfs_bmbt_rec_t));
}
}
/*
* This removes ext_diff extents from a linear (direct) extent list,
* beginning at extent index idx. If the extents are being removed
* from the end of the list (ie. truncate) then we just need to re-
* allocate the list to remove the extra space. Otherwise, if the
* extents are being removed from the middle of the existing extent
* entries, then we first need to move the extent records beginning
* at idx + ext_diff up in the list to overwrite the records being
* removed, then remove the extra space via kmem_realloc.
*/
void
xfs_iext_remove_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff) /* number of extents to remove */
{
xfs_extnum_t nextents; /* number of extents in file */
int new_size; /* size of extents after removal */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
new_size = ifp->if_bytes -
(ext_diff * sizeof(xfs_bmbt_rec_t));
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (new_size == 0) {
xfs_iext_destroy(ifp);
return;
}
/* Move extents up in the list (if needed) */
if (idx + ext_diff < nextents) {
memmove(&ifp->if_u1.if_extents[idx],
&ifp->if_u1.if_extents[idx + ext_diff],
(nextents - (idx + ext_diff)) *
sizeof(xfs_bmbt_rec_t));
}
memset(&ifp->if_u1.if_extents[nextents - ext_diff],
0, ext_diff * sizeof(xfs_bmbt_rec_t));
/*
* Reallocate the direct extent list. If the extents
* will fit inside the inode then xfs_iext_realloc_direct
* will switch from direct to inline extent allocation
* mode for us.
*/
xfs_iext_realloc_direct(ifp, new_size);
ifp->if_bytes = new_size;
}
/*
* This is called when incore extents are being removed from the
* indirection array and the extents being removed span multiple extent
* buffers. The idx parameter contains the file extent index where we
* want to begin removing extents, and the count parameter contains
* how many extents need to be removed.
*
* |-------| |-------|
* | nex1 | | | nex1 - number of extents before idx
* |-------| | count |
* | | | | count - number of extents being removed at idx
* | count | |-------|
* | | | nex2 | nex2 - number of extents after idx + count
* |-------| |-------|
*/
void
xfs_iext_remove_indirect(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing extents */
int count) /* number of extents to remove */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int erp_idx = 0; /* indirection array index */
xfs_extnum_t ext_cnt; /* extents left to remove */
xfs_extnum_t ext_diff; /* extents to remove in current list */
xfs_extnum_t nex1; /* number of extents before idx */
xfs_extnum_t nex2; /* extents after idx + count */
int page_idx = idx; /* index in target extent list */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0);
ASSERT(erp != NULL);
nex1 = page_idx;
ext_cnt = count;
while (ext_cnt) {
nex2 = MAX((erp->er_extcount - (nex1 + ext_cnt)), 0);
ext_diff = MIN(ext_cnt, (erp->er_extcount - nex1));
/*
* Check for deletion of entire list;
* xfs_iext_irec_remove() updates extent offsets.
*/
if (ext_diff == erp->er_extcount) {
xfs_iext_irec_remove(ifp, erp_idx);
ext_cnt -= ext_diff;
nex1 = 0;
if (ext_cnt) {
ASSERT(erp_idx < ifp->if_real_bytes /
XFS_IEXT_BUFSZ);
erp = &ifp->if_u1.if_ext_irec[erp_idx];
nex1 = 0;
continue;
} else {
break;
}
}
/* Move extents up (if needed) */
if (nex2) {
memmove(&erp->er_extbuf[nex1],
&erp->er_extbuf[nex1 + ext_diff],
nex2 * sizeof(xfs_bmbt_rec_t));
}
/* Zero out rest of page */
memset(&erp->er_extbuf[nex1 + nex2], 0, (XFS_IEXT_BUFSZ -
((nex1 + nex2) * sizeof(xfs_bmbt_rec_t))));
/* Update remaining counters */
erp->er_extcount -= ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -ext_diff);
ext_cnt -= ext_diff;
nex1 = 0;
erp_idx++;
erp++;
}
ifp->if_bytes -= count * sizeof(xfs_bmbt_rec_t);
xfs_iext_irec_compact(ifp);
}
/*
* Create, destroy, or resize a linear (direct) block of extents.
*/
void
xfs_iext_realloc_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* new size of extents after adding */
{
int rnew_size; /* real new size of extents */
rnew_size = new_size;
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC) ||
((new_size >= 0) && (new_size <= XFS_IEXT_BUFSZ) &&
(new_size != ifp->if_real_bytes)));
/* Free extent records */
if (new_size == 0) {
xfs_iext_destroy(ifp);
}
/* Resize direct extent list and zero any new bytes */
else if (ifp->if_real_bytes) {
/* Check if extents will fit inside the inode */
if (new_size <= XFS_INLINE_EXTS * sizeof(xfs_bmbt_rec_t)) {
xfs_iext_direct_to_inline(ifp, new_size /
(uint)sizeof(xfs_bmbt_rec_t));
ifp->if_bytes = new_size;
return;
}
if (!is_power_of_2(new_size)){
rnew_size = roundup_pow_of_two(new_size);
}
if (rnew_size != ifp->if_real_bytes) {
ifp->if_u1.if_extents =
kmem_realloc(ifp->if_u1.if_extents,
rnew_size,
ifp->if_real_bytes, KM_NOFS);
}
if (rnew_size > ifp->if_real_bytes) {
memset(&ifp->if_u1.if_extents[ifp->if_bytes /
(uint)sizeof(xfs_bmbt_rec_t)], 0,
rnew_size - ifp->if_real_bytes);
}
}
/* Switch from the inline extent buffer to a direct extent list */
else {
if (!is_power_of_2(new_size)) {
rnew_size = roundup_pow_of_two(new_size);
}
xfs_iext_inline_to_direct(ifp, rnew_size);
}
ifp->if_real_bytes = rnew_size;
ifp->if_bytes = new_size;
}
/*
* Switch from linear (direct) extent records to inline buffer.
*/
void
xfs_iext_direct_to_inline(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t nextents) /* number of extents in file */
{
ASSERT(ifp->if_flags & XFS_IFEXTENTS);
ASSERT(nextents <= XFS_INLINE_EXTS);
/*
* The inline buffer was zeroed when we switched
* from inline to direct extent allocation mode,
* so we don't need to clear it here.
*/
memcpy(ifp->if_u2.if_inline_ext, ifp->if_u1.if_extents,
nextents * sizeof(xfs_bmbt_rec_t));
kmem_free(ifp->if_u1.if_extents);
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
ifp->if_real_bytes = 0;
}
/*
* Switch from inline buffer to linear (direct) extent records.
* new_size should already be rounded up to the next power of 2
* by the caller (when appropriate), so use new_size as it is.
* However, since new_size may be rounded up, we can't update
* if_bytes here. It is the caller's responsibility to update
* if_bytes upon return.
*/
void
xfs_iext_inline_to_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* number of extents in file */
{
ifp->if_u1.if_extents = kmem_alloc(new_size, KM_NOFS);
memset(ifp->if_u1.if_extents, 0, new_size);
if (ifp->if_bytes) {
memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext,
ifp->if_bytes);
memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
sizeof(xfs_bmbt_rec_t));
}
ifp->if_real_bytes = new_size;
}
/*
* Resize an extent indirection array to new_size bytes.
*/
STATIC void
xfs_iext_realloc_indirect(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* new indirection array size */
{
int nlists; /* number of irec's (ex lists) */
int size; /* current indirection array size */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
size = nlists * sizeof(xfs_ext_irec_t);
ASSERT(ifp->if_real_bytes);
ASSERT((new_size >= 0) && (new_size != size));
if (new_size == 0) {
xfs_iext_destroy(ifp);
} else {
ifp->if_u1.if_ext_irec = (xfs_ext_irec_t *)
kmem_realloc(ifp->if_u1.if_ext_irec,
new_size, size, KM_NOFS);
}
}
/*
* Switch from indirection array to linear (direct) extent allocations.
*/
STATIC void
xfs_iext_indirect_to_direct(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_bmbt_rec_host_t *ep; /* extent record pointer */
xfs_extnum_t nextents; /* number of extents in file */
int size; /* size of file extents */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(nextents <= XFS_LINEAR_EXTS);
size = nextents * sizeof(xfs_bmbt_rec_t);
xfs_iext_irec_compact_pages(ifp);
ASSERT(ifp->if_real_bytes == XFS_IEXT_BUFSZ);
ep = ifp->if_u1.if_ext_irec->er_extbuf;
kmem_free(ifp->if_u1.if_ext_irec);
ifp->if_flags &= ~XFS_IFEXTIREC;
ifp->if_u1.if_extents = ep;
ifp->if_bytes = size;
if (nextents < XFS_LINEAR_EXTS) {
xfs_iext_realloc_direct(ifp, size);
}
}
/*
* Free incore file extents.
*/
void
xfs_iext_destroy(
xfs_ifork_t *ifp) /* inode fork pointer */
{
if (ifp->if_flags & XFS_IFEXTIREC) {
int erp_idx;
int nlists;
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
for (erp_idx = nlists - 1; erp_idx >= 0 ; erp_idx--) {
xfs_iext_irec_remove(ifp, erp_idx);
}
ifp->if_flags &= ~XFS_IFEXTIREC;
} else if (ifp->if_real_bytes) {
kmem_free(ifp->if_u1.if_extents);
} else if (ifp->if_bytes) {
memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
sizeof(xfs_bmbt_rec_t));
}
ifp->if_u1.if_extents = NULL;
ifp->if_real_bytes = 0;
ifp->if_bytes = 0;
}
/*
* Return a pointer to the extent record for file system block bno.
*/
xfs_bmbt_rec_host_t * /* pointer to found extent record */
xfs_iext_bno_to_ext(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_fileoff_t bno, /* block number to search for */
xfs_extnum_t *idxp) /* index of target extent */
{
xfs_bmbt_rec_host_t *base; /* pointer to first extent */
xfs_filblks_t blockcount = 0; /* number of blocks in extent */
xfs_bmbt_rec_host_t *ep = NULL; /* pointer to target extent */
xfs_ext_irec_t *erp = NULL; /* indirection array pointer */
int high; /* upper boundary in search */
xfs_extnum_t idx = 0; /* index of target extent */
int low; /* lower boundary in search */
xfs_extnum_t nextents; /* number of file extents */
xfs_fileoff_t startoff = 0; /* start offset of extent */
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (nextents == 0) {
*idxp = 0;
return NULL;
}
low = 0;
if (ifp->if_flags & XFS_IFEXTIREC) {
/* Find target extent list */
int erp_idx = 0;
erp = xfs_iext_bno_to_irec(ifp, bno, &erp_idx);
base = erp->er_extbuf;
high = erp->er_extcount - 1;
} else {
base = ifp->if_u1.if_extents;
high = nextents - 1;
}
/* Binary search extent records */
while (low <= high) {
idx = (low + high) >> 1;
ep = base + idx;
startoff = xfs_bmbt_get_startoff(ep);
blockcount = xfs_bmbt_get_blockcount(ep);
if (bno < startoff) {
high = idx - 1;
} else if (bno >= startoff + blockcount) {
low = idx + 1;
} else {
/* Convert back to file-based extent index */
if (ifp->if_flags & XFS_IFEXTIREC) {
idx += erp->er_extoff;
}
*idxp = idx;
return ep;
}
}
/* Convert back to file-based extent index */
if (ifp->if_flags & XFS_IFEXTIREC) {
idx += erp->er_extoff;
}
if (bno >= startoff + blockcount) {
if (++idx == nextents) {
ep = NULL;
} else {
ep = xfs_iext_get_ext(ifp, idx);
}
}
*idxp = idx;
return ep;
}
/*
* Return a pointer to the indirection array entry containing the
* extent record for filesystem block bno. Store the index of the
* target irec in *erp_idxp.
*/
xfs_ext_irec_t * /* pointer to found extent record */
xfs_iext_bno_to_irec(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_fileoff_t bno, /* block number to search for */
int *erp_idxp) /* irec index of target ext list */
{
xfs_ext_irec_t *erp = NULL; /* indirection array pointer */
xfs_ext_irec_t *erp_next; /* next indirection array entry */
int erp_idx; /* indirection array index */
int nlists; /* number of extent irec's (lists) */
int high; /* binary search upper limit */
int low; /* binary search lower limit */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp_idx = 0;
low = 0;
high = nlists - 1;
while (low <= high) {
erp_idx = (low + high) >> 1;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
erp_next = erp_idx < nlists - 1 ? erp + 1 : NULL;
if (bno < xfs_bmbt_get_startoff(erp->er_extbuf)) {
high = erp_idx - 1;
} else if (erp_next && bno >=
xfs_bmbt_get_startoff(erp_next->er_extbuf)) {
low = erp_idx + 1;
} else {
break;
}
}
*erp_idxp = erp_idx;
return erp;
}
/*
* Return a pointer to the indirection array entry containing the
* extent record at file extent index *idxp. Store the index of the
* target irec in *erp_idxp and store the page index of the target
* extent record in *idxp.
*/
xfs_ext_irec_t *
xfs_iext_idx_to_irec(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t *idxp, /* extent index (file -> page) */
int *erp_idxp, /* pointer to target irec */
int realloc) /* new bytes were just added */
{
xfs_ext_irec_t *prev; /* pointer to previous irec */
xfs_ext_irec_t *erp = NULL; /* pointer to current irec */
int erp_idx; /* indirection array index */
int nlists; /* number of irec's (ex lists) */
int high; /* binary search upper limit */
int low; /* binary search lower limit */
xfs_extnum_t page_idx = *idxp; /* extent index in target list */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
ASSERT(page_idx >= 0);
ASSERT(page_idx <= ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
ASSERT(page_idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t) || realloc);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp_idx = 0;
low = 0;
high = nlists - 1;
/* Binary search extent irec's */
while (low <= high) {
erp_idx = (low + high) >> 1;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
prev = erp_idx > 0 ? erp - 1 : NULL;
if (page_idx < erp->er_extoff || (page_idx == erp->er_extoff &&
realloc && prev && prev->er_extcount < XFS_LINEAR_EXTS)) {
high = erp_idx - 1;
} else if (page_idx > erp->er_extoff + erp->er_extcount ||
(page_idx == erp->er_extoff + erp->er_extcount &&
!realloc)) {
low = erp_idx + 1;
} else if (page_idx == erp->er_extoff + erp->er_extcount &&
erp->er_extcount == XFS_LINEAR_EXTS) {
ASSERT(realloc);
page_idx = 0;
erp_idx++;
erp = erp_idx < nlists ? erp + 1 : NULL;
break;
} else {
page_idx -= erp->er_extoff;
break;
}
}
*idxp = page_idx;
*erp_idxp = erp_idx;
return erp;
}
/*
* Allocate and initialize an indirection array once the space needed
* for incore extents increases above XFS_IEXT_BUFSZ.
*/
void
xfs_iext_irec_init(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
xfs_extnum_t nextents; /* number of extents in file */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(nextents <= XFS_LINEAR_EXTS);
erp = kmem_alloc(sizeof(xfs_ext_irec_t), KM_NOFS);
if (nextents == 0) {
ifp->if_u1.if_extents = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
} else if (!ifp->if_real_bytes) {
xfs_iext_inline_to_direct(ifp, XFS_IEXT_BUFSZ);
} else if (ifp->if_real_bytes < XFS_IEXT_BUFSZ) {
xfs_iext_realloc_direct(ifp, XFS_IEXT_BUFSZ);
}
erp->er_extbuf = ifp->if_u1.if_extents;
erp->er_extcount = nextents;
erp->er_extoff = 0;
ifp->if_flags |= XFS_IFEXTIREC;
ifp->if_real_bytes = XFS_IEXT_BUFSZ;
ifp->if_bytes = nextents * sizeof(xfs_bmbt_rec_t);
ifp->if_u1.if_ext_irec = erp;
return;
}
/*
* Allocate and initialize a new entry in the indirection array.
*/
xfs_ext_irec_t *
xfs_iext_irec_new(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx) /* index for new irec */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int i; /* loop counter */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
/* Resize indirection array */
xfs_iext_realloc_indirect(ifp, ++nlists *
sizeof(xfs_ext_irec_t));
/*
* Move records down in the array so the
* new page can use erp_idx.
*/
erp = ifp->if_u1.if_ext_irec;
for (i = nlists - 1; i > erp_idx; i--) {
memmove(&erp[i], &erp[i-1], sizeof(xfs_ext_irec_t));
}
ASSERT(i == erp_idx);
/* Initialize new extent record */
erp = ifp->if_u1.if_ext_irec;
erp[erp_idx].er_extbuf = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
memset(erp[erp_idx].er_extbuf, 0, XFS_IEXT_BUFSZ);
erp[erp_idx].er_extcount = 0;
erp[erp_idx].er_extoff = erp_idx > 0 ?
erp[erp_idx-1].er_extoff + erp[erp_idx-1].er_extcount : 0;
return (&erp[erp_idx]);
}
/*
* Remove a record from the indirection array.
*/
void
xfs_iext_irec_remove(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx) /* irec index to remove */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int i; /* loop counter */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
if (erp->er_extbuf) {
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1,
-erp->er_extcount);
kmem_free(erp->er_extbuf);
}
/* Compact extent records */
erp = ifp->if_u1.if_ext_irec;
for (i = erp_idx; i < nlists - 1; i++) {
memmove(&erp[i], &erp[i+1], sizeof(xfs_ext_irec_t));
}
/*
* Manually free the last extent record from the indirection
* array. A call to xfs_iext_realloc_indirect() with a size
* of zero would result in a call to xfs_iext_destroy() which
* would in turn call this function again, creating a nasty
* infinite loop.
*/
if (--nlists) {
xfs_iext_realloc_indirect(ifp,
nlists * sizeof(xfs_ext_irec_t));
} else {
kmem_free(ifp->if_u1.if_ext_irec);
}
ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
}
/*
* This is called to clean up large amounts of unused memory allocated
* by the indirection array. Before compacting anything though, verify
* that the indirection array is still needed and switch back to the
* linear extent list (or even the inline buffer) if possible. The
* compaction policy is as follows:
*
* Full Compaction: Extents fit into a single page (or inline buffer)
* Partial Compaction: Extents occupy less than 50% of allocated space
* No Compaction: Extents occupy at least 50% of allocated space
*/
void
xfs_iext_irec_compact(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_extnum_t nextents; /* number of extents in file */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (nextents == 0) {
xfs_iext_destroy(ifp);
} else if (nextents <= XFS_INLINE_EXTS) {
xfs_iext_indirect_to_direct(ifp);
xfs_iext_direct_to_inline(ifp, nextents);
} else if (nextents <= XFS_LINEAR_EXTS) {
xfs_iext_indirect_to_direct(ifp);
} else if (nextents < (nlists * XFS_LINEAR_EXTS) >> 1) {
xfs_iext_irec_compact_pages(ifp);
}
}
/*
* Combine extents from neighboring extent pages.
*/
void
xfs_iext_irec_compact_pages(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_ext_irec_t *erp, *erp_next;/* pointers to irec entries */
int erp_idx = 0; /* indirection array index */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
while (erp_idx < nlists - 1) {
erp = &ifp->if_u1.if_ext_irec[erp_idx];
erp_next = erp + 1;
if (erp_next->er_extcount <=
(XFS_LINEAR_EXTS - erp->er_extcount)) {
memcpy(&erp->er_extbuf[erp->er_extcount],
erp_next->er_extbuf, erp_next->er_extcount *
sizeof(xfs_bmbt_rec_t));
erp->er_extcount += erp_next->er_extcount;
/*
* Free page before removing extent record
* so er_extoffs don't get modified in
* xfs_iext_irec_remove.
*/
kmem_free(erp_next->er_extbuf);
erp_next->er_extbuf = NULL;
xfs_iext_irec_remove(ifp, erp_idx + 1);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
} else {
erp_idx++;
}
}
}
/*
* This is called to update the er_extoff field in the indirection
* array when extents have been added or removed from one of the
* extent lists. erp_idx contains the irec index to begin updating
* at and ext_diff contains the number of extents that were added
* or removed.
*/
void
xfs_iext_irec_update_extoffs(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx, /* irec index to update */
int ext_diff) /* number of new extents */
{
int i; /* loop counter */
int nlists; /* number of irec's (ex lists */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
for (i = erp_idx; i < nlists; i++) {
ifp->if_u1.if_ext_irec[i].er_extoff += ext_diff;
}
}