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gerrit-public.fairphone.software / kernel / msm-4.9 / 0cf2f7632b1789b811ab20b611c4156e6de2b055 / . / fs / ocfs2 / suballoc.c
blob: a6c442c82e3d92e14caa705ba2c538c458e06336 [file] [log] [blame]
/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* suballoc.c
*
* metadata alloc and free
* Inspired by ext3 block groups.
*
* Copyright (C) 2002, 2004 Oracle. 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; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will 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 to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/highmem.h>
#define MLOG_MASK_PREFIX ML_DISK_ALLOC
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "blockcheck.h"
#include "dlmglue.h"
#include "inode.h"
#include "journal.h"
#include "localalloc.h"
#include "suballoc.h"
#include "super.h"
#include "sysfile.h"
#include "uptodate.h"
#include "buffer_head_io.h"
#define NOT_ALLOC_NEW_GROUP 0
#define ALLOC_NEW_GROUP 0x1
#define ALLOC_GROUPS_FROM_GLOBAL 0x2
#define OCFS2_MAX_INODES_TO_STEAL 1024
static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
static int ocfs2_block_group_fill(handle_t *handle,
struct inode *alloc_inode,
struct buffer_head *bg_bh,
u64 group_blkno,
u16 my_chain,
struct ocfs2_chain_list *cl);
static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
struct inode *alloc_inode,
struct buffer_head *bh,
u64 max_block,
u64 *last_alloc_group,
int flags);
static int ocfs2_cluster_group_search(struct inode *inode,
struct buffer_head *group_bh,
u32 bits_wanted, u32 min_bits,
u64 max_block,
u16 *bit_off, u16 *bits_found);
static int ocfs2_block_group_search(struct inode *inode,
struct buffer_head *group_bh,
u32 bits_wanted, u32 min_bits,
u64 max_block,
u16 *bit_off, u16 *bits_found);
static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
struct ocfs2_alloc_context *ac,
handle_t *handle,
u32 bits_wanted,
u32 min_bits,
u16 *bit_off,
unsigned int *num_bits,
u64 *bg_blkno);
static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
int nr);
static inline int ocfs2_block_group_set_bits(handle_t *handle,
struct inode *alloc_inode,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits);
static inline int ocfs2_block_group_clear_bits(handle_t *handle,
struct inode *alloc_inode,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits);
static int ocfs2_relink_block_group(handle_t *handle,
struct inode *alloc_inode,
struct buffer_head *fe_bh,
struct buffer_head *bg_bh,
struct buffer_head *prev_bg_bh,
u16 chain);
static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
u32 wanted);
static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
u64 bg_blkno,
u16 bg_bit_off);
static inline void ocfs2_block_to_cluster_group(struct inode *inode,
u64 data_blkno,
u64 *bg_blkno,
u16 *bg_bit_off);
static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
u32 bits_wanted, u64 max_block,
int flags,
struct ocfs2_alloc_context **ac);
void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
{
struct inode *inode = ac->ac_inode;
if (inode) {
if (ac->ac_which != OCFS2_AC_USE_LOCAL)
ocfs2_inode_unlock(inode, 1);
mutex_unlock(&inode->i_mutex);
iput(inode);
ac->ac_inode = NULL;
}
brelse(ac->ac_bh);
ac->ac_bh = NULL;
}
void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
{
ocfs2_free_ac_resource(ac);
kfree(ac);
}
static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
{
return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
}
#define do_error(fmt, ...) \
do{ \
if (clean_error) \
mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__); \
else \
ocfs2_error(sb, fmt, ##__VA_ARGS__); \
} while (0)
static int ocfs2_validate_gd_self(struct super_block *sb,
struct buffer_head *bh,
int clean_error)
{
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
do_error("Group descriptor #%llu has bad signature %.*s",
(unsigned long long)bh->b_blocknr, 7,
gd->bg_signature);
return -EINVAL;
}
if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
do_error("Group descriptor #%llu has an invalid bg_blkno "
"of %llu",
(unsigned long long)bh->b_blocknr,
(unsigned long long)le64_to_cpu(gd->bg_blkno));
return -EINVAL;
}
if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
do_error("Group descriptor #%llu has an invalid "
"fs_generation of #%u",
(unsigned long long)bh->b_blocknr,
le32_to_cpu(gd->bg_generation));
return -EINVAL;
}
if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
do_error("Group descriptor #%llu has bit count %u but "
"claims that %u are free",
(unsigned long long)bh->b_blocknr,
le16_to_cpu(gd->bg_bits),
le16_to_cpu(gd->bg_free_bits_count));
return -EINVAL;
}
if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
do_error("Group descriptor #%llu has bit count %u but "
"max bitmap bits of %u",
(unsigned long long)bh->b_blocknr,
le16_to_cpu(gd->bg_bits),
8 * le16_to_cpu(gd->bg_size));
return -EINVAL;
}
return 0;
}
static int ocfs2_validate_gd_parent(struct super_block *sb,
struct ocfs2_dinode *di,
struct buffer_head *bh,
int clean_error)
{
unsigned int max_bits;
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
if (di->i_blkno != gd->bg_parent_dinode) {
do_error("Group descriptor #%llu has bad parent "
"pointer (%llu, expected %llu)",
(unsigned long long)bh->b_blocknr,
(unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
(unsigned long long)le64_to_cpu(di->i_blkno));
return -EINVAL;
}
max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
if (le16_to_cpu(gd->bg_bits) > max_bits) {
do_error("Group descriptor #%llu has bit count of %u",
(unsigned long long)bh->b_blocknr,
le16_to_cpu(gd->bg_bits));
return -EINVAL;
}
if (le16_to_cpu(gd->bg_chain) >=
le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) {
do_error("Group descriptor #%llu has bad chain %u",
(unsigned long long)bh->b_blocknr,
le16_to_cpu(gd->bg_chain));
return -EINVAL;
}
return 0;
}
#undef do_error
/*
* This version only prints errors. It does not fail the filesystem, and
* exists only for resize.
*/
int ocfs2_check_group_descriptor(struct super_block *sb,
struct ocfs2_dinode *di,
struct buffer_head *bh)
{
int rc;
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
BUG_ON(!buffer_uptodate(bh));
/*
* If the ecc fails, we return the error but otherwise
* leave the filesystem running. We know any error is
* local to this block.
*/
rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
if (rc) {
mlog(ML_ERROR,
"Checksum failed for group descriptor %llu\n",
(unsigned long long)bh->b_blocknr);
} else
rc = ocfs2_validate_gd_self(sb, bh, 1);
if (!rc)
rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
return rc;
}
static int ocfs2_validate_group_descriptor(struct super_block *sb,
struct buffer_head *bh)
{
int rc;
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
mlog(0, "Validating group descriptor %llu\n",
(unsigned long long)bh->b_blocknr);
BUG_ON(!buffer_uptodate(bh));
/*
* If the ecc fails, we return the error but otherwise
* leave the filesystem running. We know any error is
* local to this block.
*/
rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
if (rc)
return rc;
/*
* Errors after here are fatal.
*/
return ocfs2_validate_gd_self(sb, bh, 0);
}
int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
u64 gd_blkno, struct buffer_head **bh)
{
int rc;
struct buffer_head *tmp = *bh;
rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
ocfs2_validate_group_descriptor);
if (rc)
goto out;
rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
if (rc) {
brelse(tmp);
goto out;
}
/* If ocfs2_read_block() got us a new bh, pass it up. */
if (!*bh)
*bh = tmp;
out:
return rc;
}
static int ocfs2_block_group_fill(handle_t *handle,
struct inode *alloc_inode,
struct buffer_head *bg_bh,
u64 group_blkno,
u16 my_chain,
struct ocfs2_chain_list *cl)
{
int status = 0;
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
struct super_block * sb = alloc_inode->i_sb;
mlog_entry_void();
if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
"b_blocknr (%llu)",
(unsigned long long)group_blkno,
(unsigned long long) bg_bh->b_blocknr);
status = -EIO;
goto bail;
}
status = ocfs2_journal_access_gd(handle,
INODE_CACHE(alloc_inode),
bg_bh,
OCFS2_JOURNAL_ACCESS_CREATE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
memset(bg, 0, sb->s_blocksize);
strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb));
bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
bg->bg_chain = cpu_to_le16(my_chain);
bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
bg->bg_blkno = cpu_to_le64(group_blkno);
/* set the 1st bit in the bitmap to account for the descriptor block */
ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
status = ocfs2_journal_dirty(handle, bg_bh);
if (status < 0)
mlog_errno(status);
/* There is no need to zero out or otherwise initialize the
* other blocks in a group - All valid FS metadata in a block
* group stores the superblock fs_generation value at
* allocation time. */
bail:
mlog_exit(status);
return status;
}
static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
{
u16 curr, best;
best = curr = 0;
while (curr < le16_to_cpu(cl->cl_count)) {
if (le32_to_cpu(cl->cl_recs[best].c_total) >
le32_to_cpu(cl->cl_recs[curr].c_total))
best = curr;
curr++;
}
return best;
}
/*
* We expect the block group allocator to already be locked.
*/
static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
struct inode *alloc_inode,
struct buffer_head *bh,
u64 max_block,
u64 *last_alloc_group,
int flags)
{
int status, credits;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
struct ocfs2_chain_list *cl;
struct ocfs2_alloc_context *ac = NULL;
handle_t *handle = NULL;
u32 bit_off, num_bits;
u16 alloc_rec;
u64 bg_blkno;
struct buffer_head *bg_bh = NULL;
struct ocfs2_group_desc *bg;
BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
mlog_entry_void();
cl = &fe->id2.i_chain;
status = ocfs2_reserve_clusters_with_limit(osb,
le16_to_cpu(cl->cl_cpg),
max_block, flags, &ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
credits = ocfs2_calc_group_alloc_credits(osb->sb,
le16_to_cpu(cl->cl_cpg));
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
handle = NULL;
mlog_errno(status);
goto bail;
}
if (last_alloc_group && *last_alloc_group != 0) {
mlog(0, "use old allocation group %llu for block group alloc\n",
(unsigned long long)*last_alloc_group);
ac->ac_last_group = *last_alloc_group;
}
status = ocfs2_claim_clusters(osb,
handle,
ac,
le16_to_cpu(cl->cl_cpg),
&bit_off,
&num_bits);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
alloc_rec = ocfs2_find_smallest_chain(cl);
/* setup the group */
bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
mlog(0, "new descriptor, record %u, at block %llu\n",
alloc_rec, (unsigned long long)bg_blkno);
bg_bh = sb_getblk(osb->sb, bg_blkno);
if (!bg_bh) {
status = -EIO;
mlog_errno(status);
goto bail;
}
ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
status = ocfs2_block_group_fill(handle,
alloc_inode,
bg_bh,
bg_blkno,
alloc_rec,
cl);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bg = (struct ocfs2_group_desc *) bg_bh->b_data;
status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
bh, OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
le16_to_cpu(bg->bg_free_bits_count));
le32_add_cpu(&cl->cl_recs[alloc_rec].c_total, le16_to_cpu(bg->bg_bits));
cl->cl_recs[alloc_rec].c_blkno = cpu_to_le64(bg_blkno);
if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
le16_add_cpu(&cl->cl_next_free_rec, 1);
le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
le16_to_cpu(bg->bg_free_bits_count));
le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
status = ocfs2_journal_dirty(handle, bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
le32_to_cpu(fe->i_clusters)));
spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
status = 0;
/* save the new last alloc group so that the caller can cache it. */
if (last_alloc_group)
*last_alloc_group = ac->ac_last_group;
bail:
if (handle)
ocfs2_commit_trans(osb, handle);
if (ac)
ocfs2_free_alloc_context(ac);
brelse(bg_bh);
mlog_exit(status);
return status;
}
static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
struct ocfs2_alloc_context *ac,
int type,
u32 slot,
u64 *last_alloc_group,
int flags)
{
int status;
u32 bits_wanted = ac->ac_bits_wanted;
struct inode *alloc_inode;
struct buffer_head *bh = NULL;
struct ocfs2_dinode *fe;
u32 free_bits;
mlog_entry_void();
alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
if (!alloc_inode) {
mlog_errno(-EINVAL);
return -EINVAL;
}
mutex_lock(&alloc_inode->i_mutex);
status = ocfs2_inode_lock(alloc_inode, &bh, 1);
if (status < 0) {
mutex_unlock(&alloc_inode->i_mutex);
iput(alloc_inode);
mlog_errno(status);
return status;
}
ac->ac_inode = alloc_inode;
ac->ac_alloc_slot = slot;
fe = (struct ocfs2_dinode *) bh->b_data;
/* The bh was validated by the inode read inside
* ocfs2_inode_lock(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
(unsigned long long)le64_to_cpu(fe->i_blkno));
status = -EIO;
goto bail;
}
free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
le32_to_cpu(fe->id1.bitmap1.i_used);
if (bits_wanted > free_bits) {
/* cluster bitmap never grows */
if (ocfs2_is_cluster_bitmap(alloc_inode)) {
mlog(0, "Disk Full: wanted=%u, free_bits=%u\n",
bits_wanted, free_bits);
status = -ENOSPC;
goto bail;
}
if (!(flags & ALLOC_NEW_GROUP)) {
mlog(0, "Alloc File %u Full: wanted=%u, free_bits=%u, "
"and we don't alloc a new group for it.\n",
slot, bits_wanted, free_bits);
status = -ENOSPC;
goto bail;
}
status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
ac->ac_max_block,
last_alloc_group, flags);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
atomic_inc(&osb->alloc_stats.bg_extends);
/* You should never ask for this much metadata */
BUG_ON(bits_wanted >
(le32_to_cpu(fe->id1.bitmap1.i_total)
- le32_to_cpu(fe->id1.bitmap1.i_used)));
}
get_bh(bh);
ac->ac_bh = bh;
bail:
brelse(bh);
mlog_exit(status);
return status;
}
int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
int blocks,
struct ocfs2_alloc_context **ac)
{
int status;
u32 slot;
*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
if (!(*ac)) {
status = -ENOMEM;
mlog_errno(status);
goto bail;
}
(*ac)->ac_bits_wanted = blocks;
(*ac)->ac_which = OCFS2_AC_USE_META;
slot = osb->slot_num;
(*ac)->ac_group_search = ocfs2_block_group_search;
status = ocfs2_reserve_suballoc_bits(osb, (*ac),
EXTENT_ALLOC_SYSTEM_INODE,
slot, NULL, ALLOC_NEW_GROUP);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
status = 0;
bail:
if ((status < 0) && *ac) {
ocfs2_free_alloc_context(*ac);
*ac = NULL;
}
mlog_exit(status);
return status;
}
int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
struct ocfs2_extent_list *root_el,
struct ocfs2_alloc_context **ac)
{
return ocfs2_reserve_new_metadata_blocks(osb,
ocfs2_extend_meta_needed(root_el),
ac);
}
static int ocfs2_steal_inode_from_other_nodes(struct ocfs2_super *osb,
struct ocfs2_alloc_context *ac)
{
int i, status = -ENOSPC;
s16 slot = ocfs2_get_inode_steal_slot(osb);
/* Start to steal inodes from the first slot after ours. */
if (slot == OCFS2_INVALID_SLOT)
slot = osb->slot_num + 1;
for (i = 0; i < osb->max_slots; i++, slot++) {
if (slot == osb->max_slots)
slot = 0;
if (slot == osb->slot_num)
continue;
status = ocfs2_reserve_suballoc_bits(osb, ac,
INODE_ALLOC_SYSTEM_INODE,
slot, NULL,
NOT_ALLOC_NEW_GROUP);
if (status >= 0) {
ocfs2_set_inode_steal_slot(osb, slot);
break;
}
ocfs2_free_ac_resource(ac);
}
return status;
}
int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
struct ocfs2_alloc_context **ac)
{
int status;
s16 slot = ocfs2_get_inode_steal_slot(osb);
u64 alloc_group;
*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
if (!(*ac)) {
status = -ENOMEM;
mlog_errno(status);
goto bail;
}
(*ac)->ac_bits_wanted = 1;
(*ac)->ac_which = OCFS2_AC_USE_INODE;
(*ac)->ac_group_search = ocfs2_block_group_search;
/*
* stat(2) can't handle i_ino > 32bits, so we tell the
* lower levels not to allocate us a block group past that
* limit. The 'inode64' mount option avoids this behavior.
*/
if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
(*ac)->ac_max_block = (u32)~0U;
/*
* slot is set when we successfully steal inode from other nodes.
* It is reset in 3 places:
* 1. when we flush the truncate log
* 2. when we complete local alloc recovery.
* 3. when we successfully allocate from our own slot.
* After it is set, we will go on stealing inodes until we find the
* need to check our slots to see whether there is some space for us.
*/
if (slot != OCFS2_INVALID_SLOT &&
atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_INODES_TO_STEAL)
goto inode_steal;
atomic_set(&osb->s_num_inodes_stolen, 0);
alloc_group = osb->osb_inode_alloc_group;
status = ocfs2_reserve_suballoc_bits(osb, *ac,
INODE_ALLOC_SYSTEM_INODE,
osb->slot_num,
&alloc_group,
ALLOC_NEW_GROUP |
ALLOC_GROUPS_FROM_GLOBAL);
if (status >= 0) {
status = 0;
spin_lock(&osb->osb_lock);
osb->osb_inode_alloc_group = alloc_group;
spin_unlock(&osb->osb_lock);
mlog(0, "after reservation, new allocation group is "
"%llu\n", (unsigned long long)alloc_group);
/*
* Some inodes must be freed by us, so try to allocate
* from our own next time.
*/
if (slot != OCFS2_INVALID_SLOT)
ocfs2_init_inode_steal_slot(osb);
goto bail;
} else if (status < 0 && status != -ENOSPC) {
mlog_errno(status);
goto bail;
}
ocfs2_free_ac_resource(*ac);
inode_steal:
status = ocfs2_steal_inode_from_other_nodes(osb, *ac);
atomic_inc(&osb->s_num_inodes_stolen);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
status = 0;
bail:
if ((status < 0) && *ac) {
ocfs2_free_alloc_context(*ac);
*ac = NULL;
}
mlog_exit(status);
return status;
}
/* local alloc code has to do the same thing, so rather than do this
* twice.. */
int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
struct ocfs2_alloc_context *ac)
{
int status;
ac->ac_which = OCFS2_AC_USE_MAIN;
ac->ac_group_search = ocfs2_cluster_group_search;
status = ocfs2_reserve_suballoc_bits(osb, ac,
GLOBAL_BITMAP_SYSTEM_INODE,
OCFS2_INVALID_SLOT, NULL,
ALLOC_NEW_GROUP);
if (status < 0 && status != -ENOSPC) {
mlog_errno(status);
goto bail;
}
bail:
return status;
}
/* Callers don't need to care which bitmap (local alloc or main) to
* use so we figure it out for them, but unfortunately this clutters
* things a bit. */
static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
u32 bits_wanted, u64 max_block,
int flags,
struct ocfs2_alloc_context **ac)
{
int status;
mlog_entry_void();
*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
if (!(*ac)) {
status = -ENOMEM;
mlog_errno(status);
goto bail;
}
(*ac)->ac_bits_wanted = bits_wanted;
(*ac)->ac_max_block = max_block;
status = -ENOSPC;
if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
ocfs2_alloc_should_use_local(osb, bits_wanted)) {
status = ocfs2_reserve_local_alloc_bits(osb,
bits_wanted,
*ac);
if (status == -EFBIG) {
/* The local alloc window is outside ac_max_block.
* use the main bitmap. */
status = -ENOSPC;
} else if ((status < 0) && (status != -ENOSPC)) {
mlog_errno(status);
goto bail;
}
}
if (status == -ENOSPC) {
status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
}
status = 0;
bail:
if ((status < 0) && *ac) {
ocfs2_free_alloc_context(*ac);
*ac = NULL;
}
mlog_exit(status);
return status;
}
int ocfs2_reserve_clusters(struct ocfs2_super *osb,
u32 bits_wanted,
struct ocfs2_alloc_context **ac)
{
return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
ALLOC_NEW_GROUP, ac);
}
/*
* More or less lifted from ext3. I'll leave their description below:
*
* "For ext3 allocations, we must not reuse any blocks which are
* allocated in the bitmap buffer's "last committed data" copy. This
* prevents deletes from freeing up the page for reuse until we have
* committed the delete transaction.
*
* If we didn't do this, then deleting something and reallocating it as
* data would allow the old block to be overwritten before the
* transaction committed (because we force data to disk before commit).
* This would lead to corruption if we crashed between overwriting the
* data and committing the delete.
*
* @@@ We may want to make this allocation behaviour conditional on
* data-writes at some point, and disable it for metadata allocations or
* sync-data inodes."
*
* Note: OCFS2 already does this differently for metadata vs data
* allocations, as those bitmaps are separate and undo access is never
* called on a metadata group descriptor.
*/
static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
int nr)
{
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
int ret;
if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
return 0;
if (!buffer_jbd(bg_bh))
return 1;
jbd_lock_bh_state(bg_bh);
bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
if (bg)
ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
else
ret = 1;
jbd_unlock_bh_state(bg_bh);
return ret;
}
static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
struct buffer_head *bg_bh,
unsigned int bits_wanted,
unsigned int total_bits,
u16 *bit_off,
u16 *bits_found)
{
void *bitmap;
u16 best_offset, best_size;
int offset, start, found, status = 0;
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
/* Callers got this descriptor from
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
found = start = best_offset = best_size = 0;
bitmap = bg->bg_bitmap;
while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
if (offset == total_bits)
break;
if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
/* We found a zero, but we can't use it as it
* hasn't been put to disk yet! */
found = 0;
start = offset + 1;
} else if (offset == start) {
/* we found a zero */
found++;
/* move start to the next bit to test */
start++;
} else {
/* got a zero after some ones */
found = 1;
start = offset + 1;
}
if (found > best_size) {
best_size = found;
best_offset = start - found;
}
/* we got everything we needed */
if (found == bits_wanted) {
/* mlog(0, "Found it all!\n"); */
break;
}
}
/* XXX: I think the first clause is equivalent to the second
* - jlbec */
if (found == bits_wanted) {
*bit_off = start - found;
*bits_found = found;
} else if (best_size) {
*bit_off = best_offset;
*bits_found = best_size;
} else {
status = -ENOSPC;
/* No error log here -- see the comment above
* ocfs2_test_bg_bit_allocatable */
}
return status;
}
static inline int ocfs2_block_group_set_bits(handle_t *handle,
struct inode *alloc_inode,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits)
{
int status;
void *bitmap = bg->bg_bitmap;
int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
mlog_entry_void();
/* All callers get the descriptor via
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
mlog(0, "block_group_set_bits: off = %u, num = %u\n", bit_off,
num_bits);
if (ocfs2_is_cluster_bitmap(alloc_inode))
journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
status = ocfs2_journal_access_gd(handle,
INODE_CACHE(alloc_inode),
group_bh,
journal_type);
if (status < 0) {
mlog_errno(status);
goto bail;
}
le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
while(num_bits--)
ocfs2_set_bit(bit_off++, bitmap);
status = ocfs2_journal_dirty(handle,
group_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bail:
mlog_exit(status);
return status;
}
/* find the one with the most empty bits */
static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
{
u16 curr, best;
BUG_ON(!cl->cl_next_free_rec);
best = curr = 0;
while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
if (le32_to_cpu(cl->cl_recs[curr].c_free) >
le32_to_cpu(cl->cl_recs[best].c_free))
best = curr;
curr++;
}
BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
return best;
}
static int ocfs2_relink_block_group(handle_t *handle,
struct inode *alloc_inode,
struct buffer_head *fe_bh,
struct buffer_head *bg_bh,
struct buffer_head *prev_bg_bh,
u16 chain)
{
int status;
/* there is a really tiny chance the journal calls could fail,
* but we wouldn't want inconsistent blocks in *any* case. */
u64 fe_ptr, bg_ptr, prev_bg_ptr;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
/* The caller got these descriptors from
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
mlog(0, "Suballoc %llu, chain %u, move group %llu to top, prev = %llu\n",
(unsigned long long)le64_to_cpu(fe->i_blkno), chain,
(unsigned long long)le64_to_cpu(bg->bg_blkno),
(unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
fe_ptr = le64_to_cpu(fe->id2.i_chain.cl_recs[chain].c_blkno);
bg_ptr = le64_to_cpu(bg->bg_next_group);
prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
prev_bg_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
prev_bg->bg_next_group = bg->bg_next_group;
status = ocfs2_journal_dirty(handle, prev_bg_bh);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
status = ocfs2_journal_dirty(handle, bg_bh);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
status = ocfs2_journal_dirty(handle, fe_bh);
if (status < 0) {
mlog_errno(status);
goto out_rollback;
}
status = 0;
out_rollback:
if (status < 0) {
fe->id2.i_chain.cl_recs[chain].c_blkno = cpu_to_le64(fe_ptr);
bg->bg_next_group = cpu_to_le64(bg_ptr);
prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
}
mlog_exit(status);
return status;
}
static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
u32 wanted)
{
return le16_to_cpu(bg->bg_free_bits_count) > wanted;
}
/* return 0 on success, -ENOSPC to keep searching and any other < 0
* value on error. */
static int ocfs2_cluster_group_search(struct inode *inode,
struct buffer_head *group_bh,
u32 bits_wanted, u32 min_bits,
u64 max_block,
u16 *bit_off, u16 *bits_found)
{
int search = -ENOSPC;
int ret;
u64 blkoff;
struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
u16 tmp_off, tmp_found;
unsigned int max_bits, gd_cluster_off;
BUG_ON(!ocfs2_is_cluster_bitmap(inode));
if (gd->bg_free_bits_count) {
max_bits = le16_to_cpu(gd->bg_bits);
/* Tail groups in cluster bitmaps which aren't cpg
* aligned are prone to partial extention by a failed
* fs resize. If the file system resize never got to
* update the dinode cluster count, then we don't want
* to trust any clusters past it, regardless of what
* the group descriptor says. */
gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
le64_to_cpu(gd->bg_blkno));
if ((gd_cluster_off + max_bits) >
OCFS2_I(inode)->ip_clusters) {
max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
mlog(0, "Desc %llu, bg_bits %u, clusters %u, use %u\n",
(unsigned long long)le64_to_cpu(gd->bg_blkno),
le16_to_cpu(gd->bg_bits),
OCFS2_I(inode)->ip_clusters, max_bits);
}
ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
group_bh, bits_wanted,
max_bits,
&tmp_off, &tmp_found);
if (ret)
return ret;
if (max_block) {
blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
gd_cluster_off +
tmp_off + tmp_found);
mlog(0, "Checking %llu against %llu\n",
(unsigned long long)blkoff,
(unsigned long long)max_block);
if (blkoff > max_block)
return -ENOSPC;
}
/* ocfs2_block_group_find_clear_bits() might
* return success, but we still want to return
* -ENOSPC unless it found the minimum number
* of bits. */
if (min_bits <= tmp_found) {
*bit_off = tmp_off;
*bits_found = tmp_found;
search = 0; /* success */
} else if (tmp_found) {
/*
* Don't show bits which we'll be returning
* for allocation to the local alloc bitmap.
*/
ocfs2_local_alloc_seen_free_bits(osb, tmp_found);
}
}
return search;
}
static int ocfs2_block_group_search(struct inode *inode,
struct buffer_head *group_bh,
u32 bits_wanted, u32 min_bits,
u64 max_block,
u16 *bit_off, u16 *bits_found)
{
int ret = -ENOSPC;
u64 blkoff;
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
BUG_ON(min_bits != 1);
BUG_ON(ocfs2_is_cluster_bitmap(inode));
if (bg->bg_free_bits_count) {
ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
group_bh, bits_wanted,
le16_to_cpu(bg->bg_bits),
bit_off, bits_found);
if (!ret && max_block) {
blkoff = le64_to_cpu(bg->bg_blkno) + *bit_off +
*bits_found;
mlog(0, "Checking %llu against %llu\n",
(unsigned long long)blkoff,
(unsigned long long)max_block);
if (blkoff > max_block)
ret = -ENOSPC;
}
}
return ret;
}
static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
handle_t *handle,
struct buffer_head *di_bh,
u32 num_bits,
u16 chain)
{
int ret;
u32 tmp_used;
struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
ret = ocfs2_journal_dirty(handle, di_bh);
if (ret < 0)
mlog_errno(ret);
out:
return ret;
}
static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
handle_t *handle,
u32 bits_wanted,
u32 min_bits,
u16 *bit_off,
unsigned int *num_bits,
u64 gd_blkno,
u16 *bits_left)
{
int ret;
u16 found;
struct buffer_head *group_bh = NULL;
struct ocfs2_group_desc *gd;
struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
struct inode *alloc_inode = ac->ac_inode;
ret = ocfs2_read_group_descriptor(alloc_inode, di, gd_blkno,
&group_bh);
if (ret < 0) {
mlog_errno(ret);
return ret;
}
gd = (struct ocfs2_group_desc *) group_bh->b_data;
ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
ac->ac_max_block, bit_off, &found);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
*num_bits = found;
ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
*num_bits,
le16_to_cpu(gd->bg_chain));
if (ret < 0) {
mlog_errno(ret);
goto out;
}
ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
*bit_off, *num_bits);
if (ret < 0)
mlog_errno(ret);
*bits_left = le16_to_cpu(gd->bg_free_bits_count);
out:
brelse(group_bh);
return ret;
}
static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
handle_t *handle,
u32 bits_wanted,
u32 min_bits,
u16 *bit_off,
unsigned int *num_bits,
u64 *bg_blkno,
u16 *bits_left)
{
int status;
u16 chain, tmp_bits;
u32 tmp_used;
u64 next_group;
struct inode *alloc_inode = ac->ac_inode;
struct buffer_head *group_bh = NULL;
struct buffer_head *prev_group_bh = NULL;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
struct ocfs2_group_desc *bg;
chain = ac->ac_chain;
mlog(0, "trying to alloc %u bits from chain %u, inode %llu\n",
bits_wanted, chain,
(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno);
status = ocfs2_read_group_descriptor(alloc_inode, fe,
le64_to_cpu(cl->cl_recs[chain].c_blkno),
&group_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bg = (struct ocfs2_group_desc *) group_bh->b_data;
status = -ENOSPC;
/* for now, the chain search is a bit simplistic. We just use
* the 1st group with any empty bits. */
while ((status = ac->ac_group_search(alloc_inode, group_bh,
bits_wanted, min_bits,
ac->ac_max_block, bit_off,
&tmp_bits)) == -ENOSPC) {
if (!bg->bg_next_group)
break;
brelse(prev_group_bh);
prev_group_bh = NULL;
next_group = le64_to_cpu(bg->bg_next_group);
prev_group_bh = group_bh;
group_bh = NULL;
status = ocfs2_read_group_descriptor(alloc_inode, fe,
next_group, &group_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bg = (struct ocfs2_group_desc *) group_bh->b_data;
}
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
mlog(0, "alloc succeeds: we give %u bits from block group %llu\n",
tmp_bits, (unsigned long long)le64_to_cpu(bg->bg_blkno));
*num_bits = tmp_bits;
BUG_ON(*num_bits == 0);
/*
* Keep track of previous block descriptor read. When
* we find a target, if we have read more than X
* number of descriptors, and the target is reasonably
* empty, relink him to top of his chain.
*
* We've read 0 extra blocks and only send one more to
* the transaction, yet the next guy to search has a
* much easier time.
*
* Do this *after* figuring out how many bits we're taking out
* of our target group.
*/
if (ac->ac_allow_chain_relink &&
(prev_group_bh) &&
(ocfs2_block_group_reasonably_empty(bg, *num_bits))) {
status = ocfs2_relink_block_group(handle, alloc_inode,
ac->ac_bh, group_bh,
prev_group_bh, chain);
if (status < 0) {
mlog_errno(status);
goto bail;
}
}
/* Ok, claim our bits now: set the info on dinode, chainlist
* and then the group */
status = ocfs2_journal_access_di(handle,
INODE_CACHE(alloc_inode),
ac->ac_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
fe->id1.bitmap1.i_used = cpu_to_le32(*num_bits + tmp_used);
le32_add_cpu(&cl->cl_recs[chain].c_free, -(*num_bits));
status = ocfs2_journal_dirty(handle,
ac->ac_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = ocfs2_block_group_set_bits(handle,
alloc_inode,
bg,
group_bh,
*bit_off,
*num_bits);
if (status < 0) {
mlog_errno(status);
goto bail;
}
mlog(0, "Allocated %u bits from suballocator %llu\n", *num_bits,
(unsigned long long)le64_to_cpu(fe->i_blkno));
*bg_blkno = le64_to_cpu(bg->bg_blkno);
*bits_left = le16_to_cpu(bg->bg_free_bits_count);
bail:
brelse(group_bh);
brelse(prev_group_bh);
mlog_exit(status);
return status;
}
/* will give out up to bits_wanted contiguous bits. */
static int ocfs2_claim_suballoc_bits(struct ocfs2_super *osb,
struct ocfs2_alloc_context *ac,
handle_t *handle,
u32 bits_wanted,
u32 min_bits,
u16 *bit_off,
unsigned int *num_bits,
u64 *bg_blkno)
{
int status;
u16 victim, i;
u16 bits_left = 0;
u64 hint_blkno = ac->ac_last_group;
struct ocfs2_chain_list *cl;
struct ocfs2_dinode *fe;
mlog_entry_void();
BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
BUG_ON(!ac->ac_bh);
fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
/* The bh was validated by the inode read during
* ocfs2_reserve_suballoc_bits(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
le32_to_cpu(fe->id1.bitmap1.i_total)) {
ocfs2_error(osb->sb, "Chain allocator dinode %llu has %u used "
"bits but only %u total.",
(unsigned long long)le64_to_cpu(fe->i_blkno),
le32_to_cpu(fe->id1.bitmap1.i_used),
le32_to_cpu(fe->id1.bitmap1.i_total));
status = -EIO;
goto bail;
}
if (hint_blkno) {
/* Attempt to short-circuit the usual search mechanism
* by jumping straight to the most recently used
* allocation group. This helps us mantain some
* contiguousness across allocations. */
status = ocfs2_search_one_group(ac, handle, bits_wanted,
min_bits, bit_off, num_bits,
hint_blkno, &bits_left);
if (!status) {
/* Be careful to update *bg_blkno here as the
* caller is expecting it to be filled in, and
* ocfs2_search_one_group() won't do that for
* us. */
*bg_blkno = hint_blkno;
goto set_hint;
}
if (status < 0 && status != -ENOSPC) {
mlog_errno(status);
goto bail;
}
}
cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
victim = ocfs2_find_victim_chain(cl);
ac->ac_chain = victim;
ac->ac_allow_chain_relink = 1;
status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, bit_off,
num_bits, bg_blkno, &bits_left);
if (!status)
goto set_hint;
if (status < 0 && status != -ENOSPC) {
mlog_errno(status);
goto bail;
}
mlog(0, "Search of victim chain %u came up with nothing, "
"trying all chains now.\n", victim);
/* If we didn't pick a good victim, then just default to
* searching each chain in order. Don't allow chain relinking
* because we only calculate enough journal credits for one
* relink per alloc. */
ac->ac_allow_chain_relink = 0;
for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
if (i == victim)
continue;
if (!cl->cl_recs[i].c_free)
continue;
ac->ac_chain = i;
status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
bit_off, num_bits, bg_blkno,
&bits_left);
if (!status)
break;
if (status < 0 && status != -ENOSPC) {
mlog_errno(status);
goto bail;
}
}
set_hint:
if (status != -ENOSPC) {
/* If the next search of this group is not likely to
* yield a suitable extent, then we reset the last
* group hint so as to not waste a disk read */
if (bits_left < min_bits)
ac->ac_last_group = 0;
else
ac->ac_last_group = *bg_blkno;
}
bail:
mlog_exit(status);
return status;
}
int ocfs2_claim_metadata(struct ocfs2_super *osb,
handle_t *handle,
struct ocfs2_alloc_context *ac,
u32 bits_wanted,
u16 *suballoc_bit_start,
unsigned int *num_bits,
u64 *blkno_start)
{
int status;
u64 bg_blkno;
BUG_ON(!ac);
BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
status = ocfs2_claim_suballoc_bits(osb,
ac,
handle,
bits_wanted,
1,
suballoc_bit_start,
num_bits,
&bg_blkno);
if (status < 0) {
mlog_errno(status);
goto bail;
}
atomic_inc(&osb->alloc_stats.bg_allocs);
*blkno_start = bg_blkno + (u64) *suballoc_bit_start;
ac->ac_bits_given += (*num_bits);
status = 0;
bail:
mlog_exit(status);
return status;
}
static void ocfs2_init_inode_ac_group(struct inode *dir,
struct buffer_head *parent_fe_bh,
struct ocfs2_alloc_context *ac)
{
struct ocfs2_dinode *fe = (struct ocfs2_dinode *)parent_fe_bh->b_data;
/*
* Try to allocate inodes from some specific group.
*
* If the parent dir has recorded the last group used in allocation,
* cool, use it. Otherwise if we try to allocate new inode from the
* same slot the parent dir belongs to, use the same chunk.
*
* We are very careful here to avoid the mistake of setting
* ac_last_group to a group descriptor from a different (unlocked) slot.
*/
if (OCFS2_I(dir)->ip_last_used_group &&
OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
else if (le16_to_cpu(fe->i_suballoc_slot) == ac->ac_alloc_slot)
ac->ac_last_group = ocfs2_which_suballoc_group(
le64_to_cpu(fe->i_blkno),
le16_to_cpu(fe->i_suballoc_bit));
}
static inline void ocfs2_save_inode_ac_group(struct inode *dir,
struct ocfs2_alloc_context *ac)
{
OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
}
int ocfs2_claim_new_inode(struct ocfs2_super *osb,
handle_t *handle,
struct inode *dir,
struct buffer_head *parent_fe_bh,
struct ocfs2_alloc_context *ac,
u16 *suballoc_bit,
u64 *fe_blkno)
{
int status;
unsigned int num_bits;
u64 bg_blkno;
mlog_entry_void();
BUG_ON(!ac);
BUG_ON(ac->ac_bits_given != 0);
BUG_ON(ac->ac_bits_wanted != 1);
BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
status = ocfs2_claim_suballoc_bits(osb,
ac,
handle,
1,
1,
suballoc_bit,
&num_bits,
&bg_blkno);
if (status < 0) {
mlog_errno(status);
goto bail;
}
atomic_inc(&osb->alloc_stats.bg_allocs);
BUG_ON(num_bits != 1);
*fe_blkno = bg_blkno + (u64) (*suballoc_bit);
ac->ac_bits_given++;
ocfs2_save_inode_ac_group(dir, ac);
status = 0;
bail:
mlog_exit(status);
return status;
}
/* translate a group desc. blkno and it's bitmap offset into
* disk cluster offset. */
static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
u64 bg_blkno,
u16 bg_bit_off)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
u32 cluster = 0;
BUG_ON(!ocfs2_is_cluster_bitmap(inode));
if (bg_blkno != osb->first_cluster_group_blkno)
cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
cluster += (u32) bg_bit_off;
return cluster;
}
/* given a cluster offset, calculate which block group it belongs to
* and return that block offset. */
u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
u32 group_no;
BUG_ON(!ocfs2_is_cluster_bitmap(inode));
group_no = cluster / osb->bitmap_cpg;
if (!group_no)
return osb->first_cluster_group_blkno;
return ocfs2_clusters_to_blocks(inode->i_sb,
group_no * osb->bitmap_cpg);
}
/* given the block number of a cluster start, calculate which cluster
* group and descriptor bitmap offset that corresponds to. */
static inline void ocfs2_block_to_cluster_group(struct inode *inode,
u64 data_blkno,
u64 *bg_blkno,
u16 *bg_bit_off)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
BUG_ON(!ocfs2_is_cluster_bitmap(inode));
*bg_blkno = ocfs2_which_cluster_group(inode,
data_cluster);
if (*bg_blkno == osb->first_cluster_group_blkno)
*bg_bit_off = (u16) data_cluster;
else
*bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
data_blkno - *bg_blkno);
}
/*
* min_bits - minimum contiguous chunk from this total allocation we
* can handle. set to what we asked for originally for a full
* contig. allocation, set to '1' to indicate we can deal with extents
* of any size.
*/
int __ocfs2_claim_clusters(struct ocfs2_super *osb,
handle_t *handle,
struct ocfs2_alloc_context *ac,
u32 min_clusters,
u32 max_clusters,
u32 *cluster_start,
u32 *num_clusters)
{
int status;
unsigned int bits_wanted = max_clusters;
u64 bg_blkno = 0;
u16 bg_bit_off;
mlog_entry_void();
BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
&& ac->ac_which != OCFS2_AC_USE_MAIN);
if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
status = ocfs2_claim_local_alloc_bits(osb,
handle,
ac,
bits_wanted,
cluster_start,
num_clusters);
if (!status)
atomic_inc(&osb->alloc_stats.local_data);
} else {
if (min_clusters > (osb->bitmap_cpg - 1)) {
/* The only paths asking for contiguousness
* should know about this already. */
mlog(ML_ERROR, "minimum allocation requested %u exceeds "
"group bitmap size %u!\n", min_clusters,
osb->bitmap_cpg);
status = -ENOSPC;
goto bail;
}
/* clamp the current request down to a realistic size. */
if (bits_wanted > (osb->bitmap_cpg - 1))
bits_wanted = osb->bitmap_cpg - 1;
status = ocfs2_claim_suballoc_bits(osb,
ac,
handle,
bits_wanted,
min_clusters,
&bg_bit_off,
num_clusters,
&bg_blkno);
if (!status) {
*cluster_start =
ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
bg_blkno,
bg_bit_off);
atomic_inc(&osb->alloc_stats.bitmap_data);
}
}
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto bail;
}
ac->ac_bits_given += *num_clusters;
bail:
mlog_exit(status);
return status;
}
int ocfs2_claim_clusters(struct ocfs2_super *osb,
handle_t *handle,
struct ocfs2_alloc_context *ac,
u32 min_clusters,
u32 *cluster_start,
u32 *num_clusters)
{
unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
return __ocfs2_claim_clusters(osb, handle, ac, min_clusters,
bits_wanted, cluster_start, num_clusters);
}
static inline int ocfs2_block_group_clear_bits(handle_t *handle,
struct inode *alloc_inode,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits)
{
int status;
unsigned int tmp;
int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
struct ocfs2_group_desc *undo_bg = NULL;
int cluster_bitmap = 0;
mlog_entry_void();
/* The caller got this descriptor from
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
mlog(0, "off = %u, num = %u\n", bit_off, num_bits);
if (ocfs2_is_cluster_bitmap(alloc_inode))
journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
group_bh, journal_type);
if (status < 0) {
mlog_errno(status);
goto bail;
}
if (ocfs2_is_cluster_bitmap(alloc_inode))
cluster_bitmap = 1;
if (cluster_bitmap) {
jbd_lock_bh_state(group_bh);
undo_bg = (struct ocfs2_group_desc *)
bh2jh(group_bh)->b_committed_data;
BUG_ON(!undo_bg);
}
tmp = num_bits;
while(tmp--) {
ocfs2_clear_bit((bit_off + tmp),
(unsigned long *) bg->bg_bitmap);
if (cluster_bitmap)
ocfs2_set_bit(bit_off + tmp,
(unsigned long *) undo_bg->bg_bitmap);
}
le16_add_cpu(&bg->bg_free_bits_count, num_bits);
if (cluster_bitmap)
jbd_unlock_bh_state(group_bh);
status = ocfs2_journal_dirty(handle, group_bh);
if (status < 0)
mlog_errno(status);
bail:
return status;
}
/*
* expects the suballoc inode to already be locked.
*/
int ocfs2_free_suballoc_bits(handle_t *handle,
struct inode *alloc_inode,
struct buffer_head *alloc_bh,
unsigned int start_bit,
u64 bg_blkno,
unsigned int count)
{
int status = 0;
u32 tmp_used;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
struct ocfs2_chain_list *cl = &fe->id2.i_chain;
struct buffer_head *group_bh = NULL;
struct ocfs2_group_desc *group;
mlog_entry_void();
/* The alloc_bh comes from ocfs2_free_dinode() or
* ocfs2_free_clusters(). The callers have all locked the
* allocator and gotten alloc_bh from the lock call. This
* validates the dinode buffer. Any corruption that has happended
* is a code bug. */
BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
mlog(0, "%llu: freeing %u bits from group %llu, starting at %u\n",
(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno, count,
(unsigned long long)bg_blkno, start_bit);
status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
&group_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
group = (struct ocfs2_group_desc *) group_bh->b_data;
BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
status = ocfs2_block_group_clear_bits(handle, alloc_inode,
group, group_bh,
start_bit, count);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
count);
tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
status = ocfs2_journal_dirty(handle, alloc_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bail:
brelse(group_bh);
mlog_exit(status);
return status;
}
int ocfs2_free_dinode(handle_t *handle,
struct inode *inode_alloc_inode,
struct buffer_head *inode_alloc_bh,
struct ocfs2_dinode *di)
{
u64 blk = le64_to_cpu(di->i_blkno);
u16 bit = le16_to_cpu(di->i_suballoc_bit);
u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
inode_alloc_bh, bit, bg_blkno, 1);
}
int ocfs2_free_clusters(handle_t *handle,
struct inode *bitmap_inode,
struct buffer_head *bitmap_bh,
u64 start_blk,
unsigned int num_clusters)
{
int status;
u16 bg_start_bit;
u64 bg_blkno;
struct ocfs2_dinode *fe;
/* You can't ever have a contiguous set of clusters
* bigger than a block group bitmap so we never have to worry
* about looping on them. */
mlog_entry_void();
/* This is expensive. We can safely remove once this stuff has
* gotten tested really well. */
BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
&bg_start_bit);
mlog(0, "want to free %u clusters starting at block %llu\n",
num_clusters, (unsigned long long)start_blk);
mlog(0, "bg_blkno = %llu, bg_start_bit = %u\n",
(unsigned long long)bg_blkno, bg_start_bit);
status = ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
bg_start_bit, bg_blkno,
num_clusters);
if (status < 0) {
mlog_errno(status);
goto out;
}
ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
num_clusters);
out:
mlog_exit(status);
return status;
}
static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
{
printk("Block Group:\n");
printk("bg_signature: %s\n", bg->bg_signature);
printk("bg_size: %u\n", bg->bg_size);
printk("bg_bits: %u\n", bg->bg_bits);
printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
printk("bg_chain: %u\n", bg->bg_chain);
printk("bg_generation: %u\n", le32_to_cpu(bg->bg_generation));
printk("bg_next_group: %llu\n",
(unsigned long long)bg->bg_next_group);
printk("bg_parent_dinode: %llu\n",
(unsigned long long)bg->bg_parent_dinode);
printk("bg_blkno: %llu\n",
(unsigned long long)bg->bg_blkno);
}
static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
{
int i;
printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
printk("i_signature: %s\n", fe->i_signature);
printk("i_size: %llu\n",
(unsigned long long)fe->i_size);
printk("i_clusters: %u\n", fe->i_clusters);
printk("i_generation: %u\n",
le32_to_cpu(fe->i_generation));
printk("id1.bitmap1.i_used: %u\n",
le32_to_cpu(fe->id1.bitmap1.i_used));
printk("id1.bitmap1.i_total: %u\n",
le32_to_cpu(fe->id1.bitmap1.i_total));
printk("id2.i_chain.cl_cpg: %u\n", fe->id2.i_chain.cl_cpg);
printk("id2.i_chain.cl_bpc: %u\n", fe->id2.i_chain.cl_bpc);
printk("id2.i_chain.cl_count: %u\n", fe->id2.i_chain.cl_count);
printk("id2.i_chain.cl_next_free_rec: %u\n",
fe->id2.i_chain.cl_next_free_rec);
for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
printk("fe->id2.i_chain.cl_recs[%d].c_free: %u\n", i,
fe->id2.i_chain.cl_recs[i].c_free);
printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
fe->id2.i_chain.cl_recs[i].c_total);
printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
(unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
}
}
/*
* For a given allocation, determine which allocators will need to be
* accessed, and lock them, reserving the appropriate number of bits.
*
* Sparse file systems call this from ocfs2_write_begin_nolock()
* and ocfs2_allocate_unwritten_extents().
*
* File systems which don't support holes call this from
* ocfs2_extend_allocation().
*/
int ocfs2_lock_allocators(struct inode *inode,
struct ocfs2_extent_tree *et,
u32 clusters_to_add, u32 extents_to_split,
struct ocfs2_alloc_context **data_ac,
struct ocfs2_alloc_context **meta_ac)
{
int ret = 0, num_free_extents;
unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
*meta_ac = NULL;
if (data_ac)
*data_ac = NULL;
BUG_ON(clusters_to_add != 0 && data_ac == NULL);
num_free_extents = ocfs2_num_free_extents(osb, inode, et);
if (num_free_extents < 0) {
ret = num_free_extents;
mlog_errno(ret);
goto out;
}
/*
* Sparse allocation file systems need to be more conservative
* with reserving room for expansion - the actual allocation
* happens while we've got a journal handle open so re-taking
* a cluster lock (because we ran out of room for another
* extent) will violate ordering rules.
*
* Most of the time we'll only be seeing this 1 cluster at a time
* anyway.
*
* Always lock for any unwritten extents - we might want to
* add blocks during a split.
*/
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
}
if (clusters_to_add == 0)
goto out;
ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
out:
if (ret) {
if (*meta_ac) {
ocfs2_free_alloc_context(*meta_ac);
*meta_ac = NULL;
}
/*
* We cannot have an error and a non null *data_ac.
*/
}
return ret;
}
/*
* Read the inode specified by blkno to get suballoc_slot and
* suballoc_bit.
*/
static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
u16 *suballoc_slot, u16 *suballoc_bit)
{
int status;
struct buffer_head *inode_bh = NULL;
struct ocfs2_dinode *inode_fe;
mlog_entry("blkno: %llu\n", (unsigned long long)blkno);
/* dirty read disk */
status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
if (status < 0) {
mlog(ML_ERROR, "read block %llu failed %d\n",
(unsigned long long)blkno, status);
goto bail;
}
inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
mlog(ML_ERROR, "invalid inode %llu requested\n",
(unsigned long long)blkno);
status = -EINVAL;
goto bail;
}
if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
(u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
(unsigned long long)blkno,
(u32)le16_to_cpu(inode_fe->i_suballoc_slot));
status = -EINVAL;
goto bail;
}
if (suballoc_slot)
*suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
if (suballoc_bit)
*suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
bail:
brelse(inode_bh);
mlog_exit(status);
return status;
}
/*
* test whether bit is SET in allocator bitmap or not. on success, 0
* is returned and *res is 1 for SET; 0 otherwise. when fails, errno
* is returned and *res is meaningless. Call this after you have
* cluster locked against suballoc, or you may get a result based on
* non-up2date contents
*/
static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
struct inode *suballoc,
struct buffer_head *alloc_bh, u64 blkno,
u16 bit, int *res)
{
struct ocfs2_dinode *alloc_fe;
struct ocfs2_group_desc *group;
struct buffer_head *group_bh = NULL;
u64 bg_blkno;
int status;
mlog_entry("blkno: %llu bit: %u\n", (unsigned long long)blkno,
(unsigned int)bit);
alloc_fe = (struct ocfs2_dinode *)alloc_bh->b_data;
if ((bit + 1) > ocfs2_bits_per_group(&alloc_fe->id2.i_chain)) {
mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
(unsigned int)bit,
ocfs2_bits_per_group(&alloc_fe->id2.i_chain));
status = -EINVAL;
goto bail;
}
bg_blkno = ocfs2_which_suballoc_group(blkno, bit);
status = ocfs2_read_group_descriptor(suballoc, alloc_fe, bg_blkno,
&group_bh);
if (status < 0) {
mlog(ML_ERROR, "read group %llu failed %d\n",
(unsigned long long)bg_blkno, status);
goto bail;
}
group = (struct ocfs2_group_desc *) group_bh->b_data;
*res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
bail:
brelse(group_bh);
mlog_exit(status);
return status;
}
/*
* Test if the bit representing this inode (blkno) is set in the
* suballocator.
*
* On success, 0 is returned and *res is 1 for SET; 0 otherwise.
*
* In the event of failure, a negative value is returned and *res is
* meaningless.
*
* Callers must make sure to hold nfs_sync_lock to prevent
* ocfs2_delete_inode() on another node from accessing the same
* suballocator concurrently.
*/
int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
{
int status;
u16 suballoc_bit = 0, suballoc_slot = 0;
struct inode *inode_alloc_inode;
struct buffer_head *alloc_bh = NULL;
mlog_entry("blkno: %llu", (unsigned long long)blkno);
status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
&suballoc_bit);
if (status < 0) {
mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
goto bail;
}
inode_alloc_inode =
ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
suballoc_slot);
if (!inode_alloc_inode) {
/* the error code could be inaccurate, but we are not able to
* get the correct one. */
status = -EINVAL;
mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
(u32)suballoc_slot);
goto bail;
}
mutex_lock(&inode_alloc_inode->i_mutex);
status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
if (status < 0) {
mutex_unlock(&inode_alloc_inode->i_mutex);
mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
(u32)suballoc_slot, status);
goto bail;
}
status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
blkno, suballoc_bit, res);
if (status < 0)
mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
ocfs2_inode_unlock(inode_alloc_inode, 0);
mutex_unlock(&inode_alloc_inode->i_mutex);
iput(inode_alloc_inode);
brelse(alloc_bh);
bail:
mlog_exit(status);
return status;
}