// SPDX-License-Identifier: GPL-2.0+
/*
* NILFS dat/inode allocator
*
* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
*
* Originally written by Koji Sato.
* Two allocators were unified by Ryusuke Konishi and Amagai Yoshiji.
*/
#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include "mdt.h"
#include "alloc.h"
/**
* nilfs_palloc_groups_per_desc_block - get the number of groups that a group
* descriptor block can maintain
* @inode: inode of metadata file using this allocator
*/
static inline unsigned long
nilfs_palloc_groups_per_desc_block(const struct inode *inode)
{
return i_blocksize(inode) /
sizeof(struct nilfs_palloc_group_desc);
}
/**
* nilfs_palloc_groups_count - get maximum number of groups
* @inode: inode of metadata file using this allocator
*/
static inline unsigned long
nilfs_palloc_groups_count(const struct inode *inode)
{
return 1UL << (BITS_PER_LONG - (inode->i_blkbits + 3 /* log2(8) */));
}
/**
* nilfs_palloc_init_blockgroup - initialize private variables for allocator
* @inode: inode of metadata file using this allocator
* @entry_size: size of the persistent object
*/
int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned int entry_size)
{
struct nilfs_mdt_info *mi = NILFS_MDT(inode);
mi->mi_bgl = kmalloc(sizeof(*mi->mi_bgl), GFP_NOFS);
if (!mi->mi_bgl)
return -ENOMEM;
bgl_lock_init(mi->mi_bgl);
nilfs_mdt_set_entry_size(inode, entry_size, 0);
mi->mi_blocks_per_group =
DIV_ROUND_UP(nilfs_palloc_entries_per_group(inode),
mi->mi_entries_per_block) + 1;
/*
* Number of blocks in a group including entry blocks
* and a bitmap block
*/
mi->mi_blocks_per_desc_block =
nilfs_palloc_groups_per_desc_block(inode) *
mi->mi_blocks_per_group + 1;
/*
* Number of blocks per descriptor including the
* descriptor block
*/
return 0;
}
/**
* nilfs_palloc_group - get group number and offset from an entry number
* @inode: inode of metadata file using this allocator
* @nr: serial number of the entry (e.g. inode number)
* @offset: pointer to store offset number in the group
*/
static unsigned long nilfs_palloc_group(const struct inode *inode, __u64 nr,
unsigned long *offset)
{
__u64 group = nr;
*offset = do_div(group, nilfs_palloc_entries_per_group(inode));
return group;
}
/**
* nilfs_palloc_desc_blkoff - get block offset of a group descriptor block
* @inode: inode of metadata file using this allocator
* @group: group number
*
* nilfs_palloc_desc_blkoff() returns block offset of the descriptor
* block which contains a descriptor of the specified group.
*/
static unsigned long
nilfs_palloc_desc_blkoff(const struct inode *inode, unsigned long group)
{
unsigned long desc_block =
group / nilfs_palloc_groups_per_desc_block(inode);
return desc_block * NILFS_MDT(inode)->mi_blocks_per_desc_block;
}
/**
* nilfs_palloc_bitmap_blkoff - get block offset of a bitmap block
* @inode: inode of metadata file using this allocator
* @group: group number
*
* nilfs_palloc_bitmap_blkoff() returns block offset of the bitmap
* block used to allocate/deallocate entries in the specified group.
*/
static unsigned long
nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group)
{
unsigned long desc_offset =
group % nilfs_palloc_groups_per_desc_block(inode);
return nilfs_palloc_desc_blkoff(inode, group) + 1 +
desc_offset * NILFS_MDT(inode)->mi_blocks_per_group;
}
/**
* nilfs_palloc_group_desc_nfrees - get the number of free entries in a group
* @desc: pointer to descriptor structure for the group
* @lock: spin lock protecting @desc
*/
static unsigned long
nilfs_palloc_group_desc_nfrees(const struct nilfs_palloc_group_desc *desc,
spinlock_t *lock)
{
unsigned long nfree;
spin_lock(lock);
nfree = le32_to_cpu(desc->pg_nfrees);
spin_unlock(lock);
return nfree;
}
/**
* nilfs_palloc_group_desc_add_entries - adjust count of free entries
* @desc: pointer to descriptor structure for the group
* @lock: spin lock protecting @desc
* @n: delta to be added
*/
static u32
nilfs_palloc_group_desc_add_entries(struct nilfs_palloc_group_desc *desc,
spinlock_t *lock, u32 n)
{
u32 nfree;
spin_lock(lock);
le32_add_cpu(&desc->pg_nfrees, n);
nfree = le32_to_cpu(desc->pg_nfrees);
spin_unlock(lock);
return nfree;
}
/**
* nilfs_palloc_entry_blkoff - get block offset of an entry block
* @inode: inode of metadata file using this allocator
* @nr: serial number of the entry (e.g. inode number)
*/
static unsigned long
nilfs_palloc_entry_blkoff(const struct inode *inode, __u64 nr)
{
unsigned long group, group_offset;
group = nilfs_palloc_group(inode, nr, &group_offset);
return nilfs_palloc_bitmap_blkoff(inode, group) + 1 +
group_offset / NILFS_MDT(inode)->mi_entries_per_block;
}
/**
* nilfs_palloc_desc_block_init - initialize buffer of a group descriptor block
* @inode: inode of metadata file
* @bh: buffer head of the buffer to be initialized
* @kaddr: kernel address mapped for the page including the buffer
*/
static void nilfs_palloc_desc_block_init(struct inode *inode,
struct buffer_head *bh, void *kaddr)
{
struct nilfs_palloc_group_desc *desc = kaddr + bh_offset(bh);
unsigned long n = nilfs_palloc_groups_per_desc_block(inode);
__le32 nfrees;
nfrees = cpu_to_le32(nilfs_palloc_entries_per_group(inode));
while (n-- > 0) {
desc->pg_nfrees = nfrees;
desc++;
}
}
static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff,
int create,
void (*init_block)(struct inode *,
struct buffer_head *,
void *),
struct buffer_head **bhp,
struct nilfs_bh_assoc *prev,
spinlock_t *lock)
{
int ret;
spin_lock(lock);
if (prev->bh && blkoff == prev->blkoff &&
likely(buffer_uptodate(prev->bh))) {
get_bh(prev->bh);
*bhp = prev->bh;
spin_unlock(lock);
return 0;
}
spin_unlock(lock);
ret = nilfs_mdt_get_block(inode, blkoff, create, init_block, bhp);
if (!ret) {
spin_lock(lock);
/*
* The following code must be safe for change of the
* cache contents during the get block call.
*/
brelse(prev->bh);
get_bh(*bhp);
prev->bh = *bhp;
prev->blkoff = blkoff;
spin_unlock(lock);
}
return ret;
}
/**
* nilfs_palloc_delete_block - delete a block on the persistent allocator file
* @inode: inode of metadata file using this allocator
* @blkoff: block offset
* @prev: nilfs_bh_assoc struct of the last used buffer
* @lock: spin lock protecting @prev
*/
static int nilfs_palloc_delete_block(struct inode *inode, unsigned long blkoff,
struct nilfs_bh_assoc *prev,
spinlock_t *lock)
{
spin_lock(lock);
if (prev->bh && blkoff == prev->blkoff) {
brelse(prev->bh);
prev->bh = NULL;
}
spin_unlock(lock);
return nilfs_mdt_delete_block(inode, blkoff);
}
/**
* nilfs_palloc_get_desc_block - get buffer head of a group descriptor block
* @inode: inode of metadata file using this allocator
* @group: group number
* @create: create flag
* @bhp: pointer to store the resultant buffer head
*/
static int nilfs_palloc_get_desc_block(struct inode *inode,
unsigned long group,
int create, struct buffer_head **bhp)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_get_block(inode,
nilfs_palloc_desc_blkoff(inode, group),
create, nilfs_palloc_desc_block_init,
bhp, &cache->prev_desc, &cache->lock);
}
/**
* nilfs_palloc_get_bitmap_block - get buffer head of a bitmap block
* @inode: inode of metadata file using this allocator
* @group: group number
* @create: create flag
* @bhp: pointer to store the resultant buffer head
*/
static int nilfs_palloc_get_bitmap_block(struct inode *inode,
unsigned long group,
int create, struct buffer_head **bhp)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_get_block(inode,
nilfs_palloc_bitmap_blkoff(inode, group),
create, NULL, bhp,
&cache->prev_bitmap, &cache->lock);
}
/**
* nilfs_palloc_delete_bitmap_block - delete a bitmap block
* @inode: inode of metadata file using this allocator
* @group: group number
*/
static int nilfs_palloc_delete_bitmap_block(struct inode *inode,
unsigned long group)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_delete_block(inode,
nilfs_palloc_bitmap_blkoff(inode,
group),
&cache->prev_bitmap, &cache->lock);
}
/**
* nilfs_palloc_get_entry_block - get buffer head of an entry block
* @inode: inode of metadata file using this allocator
* @nr: serial number of the entry (e.g. inode number)
* @create: create flag
* @bhp: pointer to store the resultant buffer head
*/
int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr,
int create, struct buffer_head **bhp)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_get_block(inode,
nilfs_palloc_entry_blkoff(inode, nr),
create, NULL, bhp,
&cache->prev_entry, &cache->lock);
}
/**
* nilfs_palloc_delete_entry_block - delete an entry block
* @inode: inode of metadata file using this allocator
* @nr: serial number of the entry
*/
static int nilfs_palloc_delete_entry_block(struct inode *inode, __u64 nr)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_delete_block(inode,
nilfs_palloc_entry_blkoff(inode, nr),
&cache->prev_entry, &cache->lock);
}
/**
* nilfs_palloc_block_get_group_desc - get kernel address of a group descriptor
* @inode: inode of metadata file using this allocator
* @group: group number
* @bh: buffer head of the buffer storing the group descriptor block
* @kaddr: kernel address mapped for the page including the buffer
*/
static struct nilfs_palloc_group_desc *
nilfs_palloc_block_get_group_desc(const struct inode *inode,
unsigned long group,
const struct buffer_head *bh, void *kaddr)
{
return (struct nilfs_palloc_group_desc *)(kaddr + bh_offset(bh)) +
group % nilfs_palloc_groups_per_desc_block(inode);
}
/**
* nilfs_palloc_block_get_entry - get kernel address of an entry
* @inode: inode of metadata file using this allocator
* @nr: serial number of the entry (e.g. inode number)
* @bh: buffer head of the buffer storing the entry block
* @kaddr: kernel address mapped for the page including the buffer
*/
void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr,
const struct buffer_head *bh, void *kaddr)
{
unsigned long entry_offset, group_offset;
nilfs_palloc_group(inode, nr, &group_offset);
entry_offset = group_offset % NILFS_MDT(inode)->mi_entries_per_block;
return kaddr + bh_offset(bh) +
entry_offset * NILFS_MDT(inode)->mi_entry_size;
}
/**
* nilfs_palloc_find_available_slot - find available slot in a group
* @bitmap: bitmap of the group
* @target: offset number of an entry in the group (start point)
* @bsize: size in bits
* @lock: spin lock protecting @bitmap
* @wrap: whether to wrap around
*/
static int nilfs_palloc_find_available_slot(unsigned char *bitmap,
unsigned long target,
unsigned int bsize,
spinlock_t *lock, bool wrap)
{
int pos, end = bsize;
if (likely(target < bsize)) {
pos = target;
do {
pos = nilfs_find_next_zero_bit(bitmap, end, pos);
if (pos >= end)
break;
if (!nilfs_set_bit_atomic(lock, pos, bitmap))
return pos;
} while (++pos < end);
end = target;
}
if (!wrap)
return -ENOSPC;
/* wrap around */
for (pos = 0; pos < end; pos++) {
pos = nilfs_find_next_zero_bit(bitmap, end, pos);
if (pos >= end)
break;
if (!nilfs_set_bit_atomic(lock, pos, bitmap))
return pos;
}
return -ENOSPC;
}
/**
* nilfs_palloc_rest_groups_in_desc_block - get the remaining number of groups
* in a group descriptor block
* @inode: inode of metadata file using this allocator
* @curr: current group number
* @max: maximum number of groups
*/
static unsigned long
nilfs_palloc_rest_groups_in_desc_block(const struct inode *inode,
unsigned long curr, unsigned long max)
{
return min_t(unsigned long,
nilfs_palloc_groups_per_desc_block(inode) -
curr % nilfs_palloc_groups_per_desc_block(inode),
max - curr + 1);
}
/**
* nilfs_palloc_count_desc_blocks - count descriptor blocks number
* @inode: inode of metadata file using this allocator
* @desc_blocks: descriptor blocks number [out]
*/
static int nilfs_palloc_count_desc_blocks(struct inode *inode,
unsigned long *desc_blocks)
{
__u64 blknum;
int ret;
ret = nilfs_bmap_last_key(NILFS_I(inode)->i_bmap, &blknum);
if (likely(!ret))
*desc_blocks = DIV_ROUND_UP(
(unsigned long)blknum,
NILFS_MDT(inode)->mi_blocks_per_desc_block);
return ret;
}
/**
* nilfs_palloc_mdt_file_can_grow - check potential opportunity for
* MDT file growing
* @inode: inode of metadata file using this allocator
* @desc_blocks: known current descriptor blocks count
*/
static inline bool nilfs_palloc_mdt_file_can_grow(struct inode *inode,
unsigned long desc_blocks)
{
return (nilfs_palloc_groups_per_desc_block(inode) * desc_blocks) <
nilfs_palloc_groups_count(inode);
}
/**
* nilfs_palloc_count_max_entries - count max number of entries that can be
* described by descriptor blocks count
* @inode: inode of metadata file using this allocator
* @nused: current number of used entries
* @nmaxp: max number of entries [out]
*/
int nilfs_palloc_count_max_entries(struct inode *inode, u64 nused, u64 *nmaxp)
{
unsigned long desc_blocks = 0;
u64 entries_per_desc_block, nmax;
int err;
err = nilfs_palloc_count_desc_blocks(inode, &desc_blocks);
if (unlikely(err))
return err;
entries_per_desc_block = (u64)nilfs_palloc_entries_per_group(inode) *
nilfs_palloc_groups_per_desc_block(inode);
nmax = entries_per_desc_block * desc_blocks;
if (nused == nmax &&
nilfs_palloc_mdt_file_can_grow(inode, desc_blocks))
nmax += entries_per_desc_block;
if (nused > nmax)
return -ERANGE;
*nmaxp = nmax;
return 0;
}
/**
* nilfs_palloc_prepare_alloc_entry - prepare to allocate a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the allocation
* @wrap: whether to wrap around
*/
int nilfs_palloc_prepare_alloc_entry(struct inode *inode,
struct nilfs_palloc_req *req, bool wrap)
{
struct buffer_head *desc_bh, *bitmap_bh;
struct nilfs_palloc_group_desc *desc;
unsigned char *bitmap;
void *desc_kaddr, *bitmap_kaddr;
unsigned long group, maxgroup, ngroups;
unsigned long group_offset, maxgroup_offset;
unsigned long n, entries_per_group;
unsigned long i, j;
spinlock_t *lock;
int pos, ret;
ngroups = nilfs_palloc_groups_count(inode);
maxgroup = ngroups - 1;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
entries_per_group = nilfs_palloc_entries_per_group(inode);
for (i = 0; i < ngroups; i += n) {
if (group >= ngroups && wrap) {
/* wrap around */
group = 0;
maxgroup = nilfs_palloc_group(inode, req->pr_entry_nr,
&maxgroup_offset) - 1;
}
ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh);
if (ret < 0)
return ret;
desc_kaddr = kmap_local_page(desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(
inode, group, desc_bh, desc_kaddr);
n = nilfs_palloc_rest_groups_in_desc_block(inode, group,
maxgroup);
for (j = 0; j < n; j++, desc++, group++, group_offset = 0) {
lock = nilfs_mdt_bgl_lock(inode, group);
if (nilfs_palloc_group_desc_nfrees(desc, lock) == 0)
continue;
kunmap_local(desc_kaddr);
ret = nilfs_palloc_get_bitmap_block(inode, group, 1,
&bitmap_bh);
if (unlikely(ret < 0)) {
brelse(desc_bh);
return ret;
}
desc_kaddr = kmap_local_page(desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(
inode, group, desc_bh, desc_kaddr);
bitmap_kaddr = kmap_local_page(bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
pos = nilfs_palloc_find_available_slot(
bitmap, group_offset, entries_per_group, lock,
wrap);
/*
* Since the search for a free slot in the second and
* subsequent bitmap blocks always starts from the
* beginning, the wrap flag only has an effect on the
* first search.
*/
kunmap_local(bitmap_kaddr);
if (pos >= 0)
goto found;
brelse(bitmap_bh);
}
kunmap_local(desc_kaddr);
brelse(desc_bh);
}
/* no entries left */
return -ENOSPC;
found:
/* found a free entry */
nilfs_palloc_group_desc_add_entries(desc, lock, -1);
req->pr_entry_nr = entries_per_group * group + pos;
kunmap_local(desc_kaddr);
req->pr_desc_bh = desc_bh;
req->pr_bitmap_bh = bitmap_bh;
return 0;
}
/**
* nilfs_palloc_commit_alloc_entry - finish allocation of a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the allocation
*/
void nilfs_palloc_commit_alloc_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
mark_buffer_dirty(req->pr_bitmap_bh);
mark_buffer_dirty(req->pr_desc_bh);
nilfs_mdt_mark_dirty(inode);
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
}
/**
* nilfs_palloc_commit_free_entry - finish deallocating a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the removal
*/
void nilfs_palloc_commit_free_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
struct nilfs_palloc_group_desc *desc;
unsigned long group, group_offset;
unsigned char *bitmap;
void *desc_kaddr, *bitmap_kaddr;
spinlock_t *lock;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
desc_kaddr = kmap_local_page(req->pr_desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(inode, group,
req->pr_desc_bh, desc_kaddr);
bitmap_kaddr = kmap_local_page(req->pr_bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
lock = nilfs_mdt_bgl_lock(inode, group);
if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap))
nilfs_warn(inode->i_sb,
"%s (ino=%lu): entry number %llu already freed",
__func__, inode->i_ino,
(unsigned long long)req->pr_entry_nr);
else
nilfs_palloc_group_desc_add_entries(desc, lock, 1);
kunmap_local(bitmap_kaddr);
kunmap_local(desc_kaddr);
mark_buffer_dirty(req->pr_desc_bh);
mark_buffer_dirty(req->pr_bitmap_bh);
nilfs_mdt_mark_dirty(inode);
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
}
/**
* nilfs_palloc_abort_alloc_entry - cancel allocation of a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the allocation
*/
void nilfs_palloc_abort_alloc_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
struct nilfs_palloc_group_desc *desc;
void *desc_kaddr, *bitmap_kaddr;
unsigned char *bitmap;
unsigned long group, group_offset;
spinlock_t *lock;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
desc_kaddr = kmap_local_page(req->pr_desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(inode, group,
req->pr_desc_bh, desc_kaddr);
bitmap_kaddr = kmap_local_page(req->pr_bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
lock = nilfs_mdt_bgl_lock(inode, group);
if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap))
nilfs_warn(inode->i_sb,
"%s (ino=%lu): entry number %llu already freed",
__func__, inode->i_ino,
(unsigned long long)req->pr_entry_nr);
else
nilfs_palloc_group_desc_add_entries(desc, lock, 1);
kunmap_local(bitmap_kaddr);
kunmap_local(desc_kaddr);
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
req->pr_entry_nr = 0;
req->pr_bitmap_bh = NULL;
req->pr_desc_bh = NULL;
}
/**
* nilfs_palloc_prepare_free_entry - prepare to deallocate a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the removal
*/
int nilfs_palloc_prepare_free_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
struct buffer_head *desc_bh, *bitmap_bh;
unsigned long group, group_offset;
int ret;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh);
if (ret < 0)
return ret;
ret = nilfs_palloc_get_bitmap_block(inode, group, 1, &bitmap_bh);
if (ret < 0) {
brelse(desc_bh);
return ret;
}
req->pr_desc_bh = desc_bh;
req->pr_bitmap_bh = bitmap_bh;
return 0;
}
/**
* nilfs_palloc_abort_free_entry - cancel deallocating a persistent object
* @inode: inode of metadata file using this allocator
* @req: nilfs_palloc_req structure exchanged for the removal
*/
void nilfs_palloc_abort_free_entry(struct inode *inode,
struct nilfs_palloc_req *req)
{
brelse(req->pr_bitmap_bh);
brelse(req->pr_desc_bh);
req->pr_entry_nr = 0;
req->pr_bitmap_bh = NULL;
req->pr_desc_bh = NULL;
}
/**
* nilfs_palloc_freev - deallocate a set of persistent objects
* @inode: inode of metadata file using this allocator
* @entry_nrs: array of entry numbers to be deallocated
* @nitems: number of entries stored in @entry_nrs
*/
int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
{
struct buffer_head *desc_bh, *bitmap_bh;
struct nilfs_palloc_group_desc *desc;
unsigned char *bitmap;
void *desc_kaddr, *bitmap_kaddr;
unsigned long group, group_offset;
__u64 group_min_nr, last_nrs[8];
const unsigned long epg = nilfs_palloc_entries_per_group(inode);
const unsigned int epb = NILFS_MDT(inode)->mi_entries_per_block;
unsigned int entry_start, end, pos;
spinlock_t *lock;
int i, j, k, ret;
u32 nfree;
for (i = 0; i < nitems; i = j) {
int change_group = false;
int nempties = 0, n = 0;
group = nilfs_palloc_group(inode, entry_nrs[i], &group_offset);
ret = nilfs_palloc_get_desc_block(inode, group, 0, &desc_bh);
if (ret < 0)
return ret;
ret = nilfs_palloc_get_bitmap_block(inode, group, 0,
&bitmap_bh);
if (ret < 0) {
brelse(desc_bh);
return ret;
}
/* Get the first entry number of the group */
group_min_nr = (__u64)group * epg;
bitmap_kaddr = kmap_local_page(bitmap_bh->b_page);
bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
lock = nilfs_mdt_bgl_lock(inode, group);
j = i;
entry_start = rounddown(group_offset, epb);
do {
if (!nilfs_clear_bit_atomic(lock, group_offset,
bitmap)) {
nilfs_warn(inode->i_sb,
"%s (ino=%lu): entry number %llu already freed",
__func__, inode->i_ino,
(unsigned long long)entry_nrs[j]);
} else {
n++;
}
j++;
if (j >= nitems || entry_nrs[j] < group_min_nr ||
entry_nrs[j] >= group_min_nr + epg) {
change_group = true;
} else {
group_offset = entry_nrs[j] - group_min_nr;
if (group_offset >= entry_start &&
group_offset < entry_start + epb) {
/* This entry is in the same block */
continue;
}
}
/* Test if the entry block is empty or not */
end = entry_start + epb;
pos = nilfs_find_next_bit(bitmap, end, entry_start);
if (pos >= end) {
last_nrs[nempties++] = entry_nrs[j - 1];
if (nempties >= ARRAY_SIZE(last_nrs))
break;
}
if (change_group)
break;
/* Go on to the next entry block */
entry_start = rounddown(group_offset, epb);
} while (true);
kunmap_local(bitmap_kaddr);
mark_buffer_dirty(bitmap_bh);
brelse(bitmap_bh);
for (k = 0; k < nempties; k++) {
ret = nilfs_palloc_delete_entry_block(inode,
last_nrs[k]);
if (ret && ret != -ENOENT)
nilfs_warn(inode->i_sb,
"error %d deleting block that object (entry=%llu, ino=%lu) belongs to",
ret, (unsigned long long)last_nrs[k],
inode->i_ino);
}
desc_kaddr = kmap_local_page(desc_bh->b_page);
desc = nilfs_palloc_block_get_group_desc(
inode, group, desc_bh, desc_kaddr);
nfree = nilfs_palloc_group_desc_add_entries(desc, lock, n);
kunmap_local(desc_kaddr);
mark_buffer_dirty(desc_bh);
nilfs_mdt_mark_dirty(inode);
brelse(desc_bh);
if (nfree == nilfs_palloc_entries_per_group(inode)) {
ret = nilfs_palloc_delete_bitmap_block(inode, group);
if (ret && ret != -ENOENT)
nilfs_warn(inode->i_sb,
"error %d deleting bitmap block of group=%lu, ino=%lu",
ret, group, inode->i_ino);
}
}
return 0;
}
void nilfs_palloc_setup_cache(struct inode *inode,
struct nilfs_palloc_cache *cache)
{
NILFS_MDT(inode)->mi_palloc_cache = cache;
spin_lock_init(&cache->lock);
}
void nilfs_palloc_clear_cache(struct inode *inode)
{
struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
spin_lock(&cache->lock);
brelse(cache->prev_desc.bh);
brelse(cache->prev_bitmap.bh);
brelse(cache->prev_entry.bh);
cache->prev_desc.bh = NULL;
cache->prev_bitmap.bh = NULL;
cache->prev_entry.bh = NULL;
spin_unlock(&cache->lock);
}
void nilfs_palloc_destroy_cache(struct inode *inode)
{
nilfs_palloc_clear_cache(inode);
NILFS_MDT(inode)->mi_palloc_cache = NULL;
}
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