/**
* nilfs_sufile_alloc - allocate a segment
* @sufile: inode of segment usage file
* @segnump: pointer to segment number
*
* Description: nilfs_sufile_alloc() allocates a clean segment.
*
* Return Value: On success, 0 is returned and the segment number of the
* allocated segment is stored in the place pointed by @segnump. On error, one
* of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No clean segment left.
*/
int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
{
struct buffer_head *header_bh, *su_bh;
struct nilfs_sufile_header *header;
struct nilfs_segment_usage *su;
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
__u64 segnum, maxsegnum, last_alloc;
void *kaddr;
unsigned long nsegments, ncleansegs, nsus, cnt;
int ret, j;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = kaddr + bh_offset(header_bh);
ncleansegs = le64_to_cpu(header->sh_ncleansegs);
last_alloc = le64_to_cpu(header->sh_last_alloc);
kunmap_atomic(kaddr, KM_USER0);
nsegments = nilfs_sufile_get_nsegments(sufile);
maxsegnum = sui->allocmax;
segnum = last_alloc + 1;
if (segnum < sui->allocmin || segnum > sui->allocmax)
segnum = sui->allocmin;
for (cnt = 0; cnt < nsegments; cnt += nsus) {
if (segnum > maxsegnum) {
if (cnt < sui->allocmax - sui->allocmin + 1) {
/*
* wrap around in the limited region.
* if allocation started from
* sui->allocmin, this never happens.
*/
segnum = sui->allocmin;
maxsegnum = last_alloc;
} else if (segnum > sui->allocmin &&
sui->allocmax + 1 < nsegments) {
segnum = sui->allocmax + 1;
maxsegnum = nsegments - 1;
} else if (sui->allocmin > 0) {
segnum = 0;
maxsegnum = sui->allocmin - 1;
} else {
break; /* never happens */
}
}
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
&su_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
nsus = nilfs_sufile_segment_usages_in_block(
sufile, segnum, maxsegnum);
for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
if (!nilfs_segment_usage_clean(su))
continue;
/* found a clean segment */
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, -1);
le64_add_cpu(&header->sh_ndirtysegs, 1);
header->sh_last_alloc = cpu_to_le64(segnum);
kunmap_atomic(kaddr, KM_USER0);
sui->ncleansegs--;
mark_buffer_dirty(header_bh);
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
brelse(su_bh);
*segnump = segnum;
goto out_header;
}
kunmap_atomic(kaddr, KM_USER0);
brelse(su_bh);
}
/* no segments left */
ret = -ENOSPC;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
{
return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
}
static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
void *buf, unsigned cisz, size_t nci)
{
struct buffer_head *bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
struct nilfs_cpinfo *ci = buf;
__u64 curr = *cnop, next;
unsigned long curr_blkoff, next_blkoff;
void *kaddr;
int n = 0, ret;
down_read(&NILFS_MDT(cpfile)->mi_sem);
if (curr == 0) {
ret = nilfs_cpfile_get_header_block(cpfile, &bh);
if (ret < 0)
goto out;
kaddr = kmap_atomic(bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
curr = le64_to_cpu(header->ch_snapshot_list.ssl_next);
kunmap_atomic(kaddr, KM_USER0);
brelse(bh);
if (curr == 0) {
ret = 0;
goto out;
}
} else if (unlikely(curr == ~(__u64)0)) {
ret = 0;
goto out;
}
curr_blkoff = nilfs_cpfile_get_blkoff(cpfile, curr);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, 0, &bh);
if (unlikely(ret < 0)) {
if (ret == -ENOENT)
ret = 0; /* No snapshots (started from a hole block) */
goto out;
}
kaddr = kmap_atomic(bh->b_page, KM_USER0);
while (n < nci) {
cp = nilfs_cpfile_block_get_checkpoint(cpfile, curr, bh, kaddr);
curr = ~(__u64)0; /* Terminator */
if (unlikely(nilfs_checkpoint_invalid(cp) ||
!nilfs_checkpoint_snapshot(cp)))
break;
nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, ci);
ci = (void *)ci + cisz;
n++;
next = le64_to_cpu(cp->cp_snapshot_list.ssl_next);
if (next == 0)
break; /* reach end of the snapshot list */
next_blkoff = nilfs_cpfile_get_blkoff(cpfile, next);
if (curr_blkoff != next_blkoff) {
kunmap_atomic(kaddr, KM_USER0);
brelse(bh);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, next,
0, &bh);
if (unlikely(ret < 0)) {
WARN_ON(ret == -ENOENT);
goto out;
}
kaddr = kmap_atomic(bh->b_page, KM_USER0);
}
curr = next;
curr_blkoff = next_blkoff;
}
kunmap_atomic(kaddr, KM_USER0);
brelse(bh);
*cnop = curr;
ret = n;
out:
up_read(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
unsigned long ino)
{
struct nilfs_iget_args args = {
.ino = ino, .root = root, .cno = 0, .for_gc = 0
};
return ilookup5(sb, ino, nilfs_iget_test, &args);
}
struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
unsigned long ino)
{
struct nilfs_iget_args args = {
.ino = ino, .root = root, .cno = 0, .for_gc = 0
};
return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
}
struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
unsigned long ino)
{
struct inode *inode;
int err;
inode = nilfs_iget_locked(sb, root, ino);
if (unlikely(!inode))
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
err = __nilfs_read_inode(sb, root, ino, inode);
if (unlikely(err)) {
iget_failed(inode);
return ERR_PTR(err);
}
unlock_new_inode(inode);
return inode;
}
struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
__u64 cno)
{
struct nilfs_iget_args args = {
.ino = ino, .root = NULL, .cno = cno, .for_gc = 1
};
struct inode *inode;
int err;
inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
if (unlikely(!inode))
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
err = nilfs_init_gcinode(inode);
if (unlikely(err)) {
iget_failed(inode);
return ERR_PTR(err);
}
unlock_new_inode(inode);
return inode;
}
void nilfs_write_inode_common(struct inode *inode,
struct nilfs_inode *raw_inode, int has_bmap)
{
struct nilfs_inode_info *ii = NILFS_I(inode);
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
raw_inode->i_size = cpu_to_le64(inode->i_size);
raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
raw_inode->i_flags = cpu_to_le32(ii->i_flags);
raw_inode->i_generation = cpu_to_le32(inode->i_generation);
if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
/* zero-fill unused portion in the case of super root block */
raw_inode->i_xattr = 0;
raw_inode->i_pad = 0;
memset((void *)raw_inode + sizeof(*raw_inode), 0,
nilfs->ns_inode_size - sizeof(*raw_inode));
}
if (has_bmap)
nilfs_bmap_write(ii->i_bmap, raw_inode);
else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
raw_inode->i_device_code =
cpu_to_le64(huge_encode_dev(inode->i_rdev));
/* When extending inode, nilfs->ns_inode_size should be checked
for substitutions of appended fields */
}
void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
{
ino_t ino = inode->i_ino;
struct nilfs_inode_info *ii = NILFS_I(inode);
struct inode *ifile = ii->i_root->ifile;
struct nilfs_inode *raw_inode;
raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
nilfs_write_inode_common(inode, raw_inode, 0);
/* XXX: call with has_bmap = 0 is a workaround to avoid
deadlock of bmap. This delays update of i_bmap to just
before writing */
nilfs_ifile_unmap_inode(ifile, ino, ibh);
}
#define NILFS_MAX_TRUNCATE_BLOCKS 16384 /* 64MB for 4KB block */
static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
unsigned long from)
{
unsigned long b;
int ret;
if (!test_bit(NILFS_I_BMAP, &ii->i_state))
return;
repeat:
ret = nilfs_bmap_last_key(ii->i_bmap, &b);
if (ret == -ENOENT)
return;
else if (ret < 0)
goto failed;
if (b < from)
return;
b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
ret = nilfs_bmap_truncate(ii->i_bmap, b);
nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
if (!ret || (ret == -ENOMEM &&
nilfs_bmap_truncate(ii->i_bmap, b) == 0))
goto repeat;
failed:
nilfs_warning(ii->vfs_inode.i_sb, __func__,
"failed to truncate bmap (ino=%lu, err=%d)",
ii->vfs_inode.i_ino, ret);
}
void nilfs_truncate(struct inode *inode)
{
unsigned long blkoff;
unsigned int blocksize;
struct nilfs_transaction_info ti;
struct super_block *sb = inode->i_sb;
struct nilfs_inode_info *ii = NILFS_I(inode);
if (!test_bit(NILFS_I_BMAP, &ii->i_state))
return;
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
return;
blocksize = sb->s_blocksize;
blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
nilfs_transaction_begin(sb, &ti, 0); /* never fails */
block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
nilfs_truncate_bmap(ii, blkoff);
inode->i_mtime = inode->i_ctime = CURRENT_TIME;
if (IS_SYNC(inode))
nilfs_set_transaction_flag(NILFS_TI_SYNC);
nilfs_mark_inode_dirty(inode);
nilfs_set_file_dirty(inode, 0);
nilfs_transaction_commit(sb);
/* May construct a logical segment and may fail in sync mode.
But truncate has no return value. */
}
void nilfs_palloc_destroy_cache(struct inode *inode)
{
nilfs_palloc_clear_cache(inode);
NILFS_MDT(inode)->mi_palloc_cache = NULL;
}
int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
__u64 start,
__u64 end)
{
struct buffer_head *header_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
__u64 cno;
void *kaddr;
unsigned long tnicps;
int ret, ncps, nicps, count, i;
if (unlikely(start == 0 || start > end)) {
printk(KERN_ERR "%s: invalid range of checkpoint numbers: "
"[%llu, %llu)\n", __func__,
(unsigned long long)start, (unsigned long long)end);
return -EINVAL;
}
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_sem;
tnicps = 0;
for (cno = start; cno < end; cno += ncps) {
ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, end);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0) {
if (ret != -ENOENT)
break;
/* skip hole */
ret = 0;
continue;
}
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(
cpfile, cno, cp_bh, kaddr);
nicps = 0;
for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
WARN_ON(nilfs_checkpoint_snapshot(cp));
if (!nilfs_checkpoint_invalid(cp)) {
nilfs_checkpoint_set_invalid(cp);
nicps++;
}
}
if (nicps > 0) {
tnicps += nicps;
nilfs_mdt_mark_buffer_dirty(cp_bh);
nilfs_mdt_mark_dirty(cpfile);
if (!nilfs_cpfile_is_in_first(cpfile, cno)) {
count =
nilfs_cpfile_block_sub_valid_checkpoints(
cpfile, cp_bh, kaddr, nicps);
if (count == 0) {
/* make hole */
kunmap_atomic(kaddr, KM_USER0);
brelse(cp_bh);
ret =
nilfs_cpfile_delete_checkpoint_block(
cpfile, cno);
if (ret == 0)
continue;
printk(KERN_ERR
"%s: cannot delete block\n",
__func__);
break;
}
}
}
kunmap_atomic(kaddr, KM_USER0);
brelse(cp_bh);
}
if (tnicps > 0) {
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh,
kaddr);
le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
kunmap_atomic(kaddr, KM_USER0);
}
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
static inline struct nilfs_ifile_info *NILFS_IFILE_I(struct inode *ifile)
{
return (struct nilfs_ifile_info *)NILFS_MDT(ifile);
}
/**
* nilfs_sufile_set_suinfo - sets segment usage info
* @sufile: inode of segment usage file
* @buf: array of suinfo_update
* @supsz: byte size of suinfo_update
* @nsup: size of suinfo_update array
*
* Description: Takes an array of nilfs_suinfo_update structs and updates
* segment usage accordingly. Only the fields indicated by the sup_flags
* are updated.
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid values in input (segment number, flags or nblocks)
*/
ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
unsigned int supsz, size_t nsup)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh, *bh;
struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
struct nilfs_segment_usage *su;
void *kaddr;
unsigned long blkoff, prev_blkoff;
int cleansi, cleansu, dirtysi, dirtysu;
long ncleaned = 0, ndirtied = 0;
int ret = 0;
if (unlikely(nsup == 0))
return ret;
for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
if (sup->sup_segnum >= nilfs->ns_nsegments
|| (sup->sup_flags &
(~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
|| (nilfs_suinfo_update_nblocks(sup) &&
sup->sup_sui.sui_nblocks >
nilfs->ns_blocks_per_segment))
return -EINVAL;
}
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
sup = buf;
blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
kaddr = kmap_atomic(bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, sup->sup_segnum, bh, kaddr);
if (nilfs_suinfo_update_lastmod(sup))
su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
if (nilfs_suinfo_update_nblocks(sup))
su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
if (nilfs_suinfo_update_flags(sup)) {
/*
* Active flag is a virtual flag projected by running
* nilfs kernel code - drop it not to write it to
* disk.
*/
sup->sup_sui.sui_flags &=
~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
cleansi = nilfs_suinfo_clean(&sup->sup_sui);
cleansu = nilfs_segment_usage_clean(su);
dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);
dirtysu = nilfs_segment_usage_dirty(su);
if (cleansi && !cleansu)
++ncleaned;
else if (!cleansi && cleansu)
--ncleaned;
if (dirtysi && !dirtysu)
++ndirtied;
else if (!dirtysi && dirtysu)
--ndirtied;
su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
}
kunmap_atomic(kaddr, KM_USER0);
sup = (void *)sup + supsz;
if (sup >= supend)
break;
prev_blkoff = blkoff;
blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
if (blkoff == prev_blkoff)
continue;
/* get different block */
mark_buffer_dirty(bh);
put_bh(bh);
ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
if (unlikely(ret < 0))
goto out_mark;
}
mark_buffer_dirty(bh);
put_bh(bh);
out_mark:
if (ncleaned || ndirtied) {
nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,
(u64)ndirtied);
NILFS_SUI(sufile)->ncleansegs += ncleaned;
}
nilfs_mdt_mark_dirty(sufile);
out_header:
put_bh(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
static void nilfs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
<<<<<<< HEAD
static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
{
return (struct nilfs_dat_info *)NILFS_MDT(dat);
}
static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *header_bh, *next_bh, *prev_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
struct nilfs_snapshot_list *list;
__u64 next, prev;
void *kaddr;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(cp_bh->b_page);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
kunmap_atomic(kaddr);
goto out_cp;
}
if (!nilfs_checkpoint_snapshot(cp)) {
ret = 0;
kunmap_atomic(kaddr);
goto out_cp;
}
list = &cp->cp_snapshot_list;
next = le64_to_cpu(list->ssl_next);
prev = le64_to_cpu(list->ssl_prev);
kunmap_atomic(kaddr);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_cp;
if (next != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, 0,
&next_bh);
if (ret < 0)
goto out_header;
} else {
next_bh = header_bh;
get_bh(next_bh);
}
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_next;
} else {
prev_bh = header_bh;
get_bh(prev_bh);
}
kaddr = kmap_atomic(next_bh->b_page);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, next, next_bh, kaddr);
list->ssl_prev = cpu_to_le64(prev);
kunmap_atomic(kaddr);
kaddr = kmap_atomic(prev_bh->b_page);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, prev, prev_bh, kaddr);
list->ssl_next = cpu_to_le64(next);
kunmap_atomic(kaddr);
kaddr = kmap_atomic(cp_bh->b_page);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
cp->cp_snapshot_list.ssl_next = cpu_to_le64(0);
cp->cp_snapshot_list.ssl_prev = cpu_to_le64(0);
nilfs_checkpoint_clear_snapshot(cp);
kunmap_atomic(kaddr);
kaddr = kmap_atomic(header_bh->b_page);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
le64_add_cpu(&header->ch_nsnapshots, -1);
kunmap_atomic(kaddr);
mark_buffer_dirty(next_bh);
mark_buffer_dirty(prev_bh);
mark_buffer_dirty(cp_bh);
mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
brelse(prev_bh);
out_next:
brelse(next_bh);
out_header:
brelse(header_bh);
out_cp:
brelse(cp_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
__u64 start, __u64 len)
{
struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
__u64 logical = 0, phys = 0, size = 0;
__u32 flags = 0;
loff_t isize;
sector_t blkoff, end_blkoff;
sector_t delalloc_blkoff;
unsigned long delalloc_blklen;
unsigned int blkbits = inode->i_blkbits;
int ret, n;
ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
if (ret)
return ret;
mutex_lock(&inode->i_mutex);
isize = i_size_read(inode);
blkoff = start >> blkbits;
end_blkoff = (start + len - 1) >> blkbits;
delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
&delalloc_blkoff);
do {
__u64 blkphy;
unsigned int maxblocks;
if (delalloc_blklen && blkoff == delalloc_blkoff) {
if (size) {
/* End of the current extent */
ret = fiemap_fill_next_extent(
fieinfo, logical, phys, size, flags);
if (ret)
break;
}
if (blkoff > end_blkoff)
break;
flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
logical = blkoff << blkbits;
phys = 0;
size = delalloc_blklen << blkbits;
blkoff = delalloc_blkoff + delalloc_blklen;
delalloc_blklen = nilfs_find_uncommitted_extent(
inode, blkoff, &delalloc_blkoff);
continue;
}
/*
* Limit the number of blocks that we look up so as
* not to get into the next delayed allocation extent.
*/
maxblocks = INT_MAX;
if (delalloc_blklen)
maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
maxblocks);
blkphy = 0;
down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
n = nilfs_bmap_lookup_contig(
NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
if (n < 0) {
int past_eof;
if (unlikely(n != -ENOENT))
break; /* error */
/* HOLE */
blkoff++;
past_eof = ((blkoff << blkbits) >= isize);
if (size) {
/* End of the current extent */
if (past_eof)
flags |= FIEMAP_EXTENT_LAST;
ret = fiemap_fill_next_extent(
fieinfo, logical, phys, size, flags);
if (ret)
break;
size = 0;
}
if (blkoff > end_blkoff || past_eof)
break;
} else {
if (size) {
if (phys && blkphy << blkbits == phys + size) {
/* The current extent goes on */
size += n << blkbits;
} else {
/* Terminate the current extent */
ret = fiemap_fill_next_extent(
fieinfo, logical, phys, size,
flags);
if (ret || blkoff > end_blkoff)
break;
/* Start another extent */
flags = FIEMAP_EXTENT_MERGED;
logical = blkoff << blkbits;
phys = blkphy << blkbits;
size = n << blkbits;
}
} else {
/* Start a new extent */
flags = FIEMAP_EXTENT_MERGED;
logical = blkoff << blkbits;
phys = blkphy << blkbits;
size = n << blkbits;
}
blkoff += n;
}
cond_resched();
} while (true);
/* If ret is 1 then we just hit the end of the extent array */
if (ret == 1)
ret = 0;
mutex_unlock(&inode->i_mutex);
return ret;
}
/**
* nilfs_get_block() - get a file block on the filesystem (callback function)
* @inode - inode struct of the target file
* @blkoff - file block number
* @bh_result - buffer head to be mapped on
* @create - indicate whether allocating the block or not when it has not
* been allocated yet.
*
* This function does not issue actual read request of the specified data
* block. It is done by VFS.
*/
int nilfs_get_block(struct inode *inode, sector_t blkoff,
struct buffer_head *bh_result, int create)
{
struct nilfs_inode_info *ii = NILFS_I(inode);
struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
__u64 blknum = 0;
int err = 0, ret;
unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
if (ret >= 0) { /* found */
map_bh(bh_result, inode->i_sb, blknum);
if (ret > 0)
bh_result->b_size = (ret << inode->i_blkbits);
goto out;
}
/* data block was not found */
if (ret == -ENOENT && create) {
struct nilfs_transaction_info ti;
bh_result->b_blocknr = 0;
err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
if (unlikely(err))
goto out;
err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
(unsigned long)bh_result);
if (unlikely(err != 0)) {
if (err == -EEXIST) {
/*
* The get_block() function could be called
* from multiple callers for an inode.
* However, the page having this block must
* be locked in this case.
*/
printk(KERN_WARNING
"nilfs_get_block: a race condition "
"while inserting a data block. "
"(inode number=%lu, file block "
"offset=%llu)\n",
inode->i_ino,
(unsigned long long)blkoff);
err = 0;
}
nilfs_transaction_abort(inode->i_sb);
goto out;
}
nilfs_mark_inode_dirty(inode);
nilfs_transaction_commit(inode->i_sb); /* never fails */
/* Error handling should be detailed */
set_buffer_new(bh_result);
set_buffer_delay(bh_result);
map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
to proper value */
} else if (ret == -ENOENT) {
/* not found is not error (e.g. hole); must return without
the mapped state flag. */
;
} else {
err = ret;
}
out:
return err;
}
static inline unsigned long
nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
{
return NILFS_MDT(sufile)->mi_entries_per_block;
}
/**
* nilfs_get_block() - get a file block on the filesystem (callback function)
* @inode - inode struct of the target file
* @blkoff - file block number
* @bh_result - buffer head to be mapped on
* @create - indicate whether allocating the block or not when it has not
* been allocated yet.
*
* This function does not issue actual read request of the specified data
* block. It is done by VFS.
* Bulk read for direct-io is not supported yet. (should be supported)
*/
int nilfs_get_block(struct inode *inode, sector_t blkoff,
struct buffer_head *bh_result, int create)
{
struct nilfs_inode_info *ii = NILFS_I(inode);
unsigned long blknum = 0;
int err = 0, ret;
struct inode *dat = nilfs_dat_inode(NILFS_I_NILFS(inode));
/* This exclusion control is a workaround; should be revised */
down_read(&NILFS_MDT(dat)->mi_sem); /* XXX */
ret = nilfs_bmap_lookup(ii->i_bmap, (unsigned long)blkoff, &blknum);
up_read(&NILFS_MDT(dat)->mi_sem); /* XXX */
if (ret == 0) { /* found */
map_bh(bh_result, inode->i_sb, blknum);
goto out;
}
/* data block was not found */
if (ret == -ENOENT && create) {
struct nilfs_transaction_info ti;
bh_result->b_blocknr = 0;
err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
if (unlikely(err))
goto out;
err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
(unsigned long)bh_result);
if (unlikely(err != 0)) {
if (err == -EEXIST) {
/*
* The get_block() function could be called
* from multiple callers for an inode.
* However, the page having this block must
* be locked in this case.
*/
printk(KERN_WARNING
"nilfs_get_block: a race condition "
"while inserting a data block. "
"(inode number=%lu, file block "
"offset=%llu)\n",
inode->i_ino,
(unsigned long long)blkoff);
err = 0;
} else if (err == -EINVAL) {
nilfs_error(inode->i_sb, __func__,
"broken bmap (inode=%lu)\n",
inode->i_ino);
err = -EIO;
}
nilfs_transaction_abort(inode->i_sb);
goto out;
}
nilfs_transaction_commit(inode->i_sb); /* never fails */
/* Error handling should be detailed */
set_buffer_new(bh_result);
map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
to proper value */
} else if (ret == -ENOENT) {
/* not found is not error (e.g. hole); must return without
the mapped state flag. */
;
} else {
err = ret;
}
out:
return err;
}
/**
* nilfs_sufile_truncate_range - truncate range of segment array
* @sufile: inode of segment usage file
* @start: start segment number (inclusive)
* @end: end segment number (inclusive)
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid number of segments specified
*
* %-EBUSY - Dirty or active segments are present in the range
*/
static int nilfs_sufile_truncate_range(struct inode *sufile,
__u64 start, __u64 end)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh;
struct buffer_head *su_bh;
struct nilfs_segment_usage *su, *su2;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
unsigned long segusages_per_block;
unsigned long nsegs, ncleaned;
__u64 segnum;
void *kaddr;
ssize_t n, nc;
int ret;
int j;
nsegs = nilfs_sufile_get_nsegments(sufile);
ret = -EINVAL;
if (start > end || start >= nsegs)
goto out;
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out;
segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
ncleaned = 0;
for (segnum = start; segnum <= end; segnum += n) {
n = min_t(unsigned long,
segusages_per_block -
nilfs_sufile_get_offset(sufile, segnum),
end - segnum + 1);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out_header;
/* hole */
continue;
}
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
su2 = su;
for (j = 0; j < n; j++, su = (void *)su + susz) {
if ((le32_to_cpu(su->su_flags) &
~(1UL << NILFS_SEGMENT_USAGE_ERROR)) ||
nilfs_segment_is_active(nilfs, segnum + j)) {
ret = -EBUSY;
kunmap_atomic(kaddr, KM_USER0);
brelse(su_bh);
goto out_header;
}
}
nc = 0;
for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
if (nilfs_segment_usage_error(su)) {
nilfs_segment_usage_set_clean(su);
nc++;
}
}
kunmap_atomic(kaddr, KM_USER0);
if (nc > 0) {
mark_buffer_dirty(su_bh);
ncleaned += nc;
}
brelse(su_bh);
if (n == segusages_per_block) {
/* make hole */
nilfs_sufile_delete_segment_usage_block(sufile, segnum);
}
}
ret = 0;
out_header:
if (ncleaned > 0) {
NILFS_SUI(sufile)->ncleansegs += ncleaned;
nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
nilfs_mdt_mark_dirty(sufile);
}
brelse(header_bh);
out:
return ret;
}
int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
{
struct buffer_head *header_bh, *su_bh;
struct nilfs_sufile_header *header;
struct nilfs_segment_usage *su;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
__u64 segnum, maxsegnum, last_alloc;
void *kaddr;
unsigned long nsegments, ncleansegs, nsus;
int ret, i, j;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = kaddr + bh_offset(header_bh);
ncleansegs = le64_to_cpu(header->sh_ncleansegs);
last_alloc = le64_to_cpu(header->sh_last_alloc);
kunmap_atomic(kaddr, KM_USER0);
nsegments = nilfs_sufile_get_nsegments(sufile);
segnum = last_alloc + 1;
maxsegnum = nsegments - 1;
for (i = 0; i < nsegments; i += nsus) {
if (segnum >= nsegments) {
/* wrap around */
segnum = 0;
maxsegnum = last_alloc;
}
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
&su_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
nsus = nilfs_sufile_segment_usages_in_block(
sufile, segnum, maxsegnum);
for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
if (!nilfs_segment_usage_clean(su))
continue;
/* found a clean segment */
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, -1);
le64_add_cpu(&header->sh_ndirtysegs, 1);
header->sh_last_alloc = cpu_to_le64(segnum);
kunmap_atomic(kaddr, KM_USER0);
NILFS_SUI(sufile)->ncleansegs--;
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
brelse(su_bh);
*segnump = segnum;
goto out_header;
}
kunmap_atomic(kaddr, KM_USER0);
brelse(su_bh);
}
/* no segments left */
ret = -ENOSPC;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
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);
}
static unsigned long
nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
{
__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
}
static inline unsigned long
nilfs_cpfile_checkpoints_per_block(const struct inode *cpfile)
{
return NILFS_MDT(cpfile)->mi_entries_per_block;
}
/**
* nilfs_sufile_trim_fs() - trim ioctl handle function
* @sufile: inode of segment usage file
* @range: fstrim_range structure
*
* start: First Byte to trim
* len: number of Bytes to trim from start
* minlen: minimum extent length in Bytes
*
* Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
* from start to start+len. start is rounded up to the next block boundary
* and start+len is rounded down. For each clean segment blkdev_issue_discard
* function is invoked.
*
* Return Value: On success, 0 is returned or negative error code, otherwise.
*/
int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *su_bh;
struct nilfs_segment_usage *su;
void *kaddr;
size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;
sector_t seg_start, seg_end, start_block, end_block;
sector_t start = 0, nblocks = 0;
u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
int ret = 0;
unsigned int sects_per_block;
sects_per_block = (1 << nilfs->ns_blocksize_bits) /
bdev_logical_block_size(nilfs->ns_bdev);
len = range->len >> nilfs->ns_blocksize_bits;
minlen = range->minlen >> nilfs->ns_blocksize_bits;
max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
return -EINVAL;
start_block = (range->start + nilfs->ns_blocksize - 1) >>
nilfs->ns_blocksize_bits;
/*
* range->len can be very large (actually, it is set to
* ULLONG_MAX by default) - truncate upper end of the range
* carefully so as not to overflow.
*/
if (max_blocks - start_block < len)
end_block = max_blocks - 1;
else
end_block = start_block + len - 1;
segnum = nilfs_get_segnum_of_block(nilfs, start_block);
segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
down_read(&NILFS_MDT(sufile)->mi_sem);
while (segnum <= segnum_end) {
n = nilfs_sufile_segment_usages_in_block(sufile, segnum,
segnum_end);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out_sem;
/* hole */
segnum += n;
continue;
}
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum,
su_bh, kaddr);
for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
if (!nilfs_segment_usage_clean(su))
continue;
nilfs_get_segment_range(nilfs, segnum, &seg_start,
&seg_end);
if (!nblocks) {
/* start new extent */
start = seg_start;
nblocks = seg_end - seg_start + 1;
continue;
}
if (start + nblocks == seg_start) {
/* add to previous extent */
nblocks += seg_end - seg_start + 1;
continue;
}
/* discard previous extent */
if (start < start_block) {
nblocks -= start_block - start;
start = start_block;
}
if (nblocks >= minlen) {
kunmap_atomic(kaddr, KM_USER0);
ret = compat_blkdev_issue_discard(
nilfs->ns_bdev, start * sects_per_block,
nblocks * sects_per_block, GFP_NOFS, 0);
if (ret < 0) {
put_bh(su_bh);
goto out_sem;
}
ndiscarded += nblocks;
kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
}
/* start new extent */
start = seg_start;
nblocks = seg_end - seg_start + 1;
}
kunmap_atomic(kaddr, KM_USER0);
put_bh(su_bh);
}
if (nblocks) {
/* discard last extent */
if (start < start_block) {
nblocks -= start_block - start;
start = start_block;
}
if (start + nblocks > end_block + 1)
nblocks = end_block - start + 1;
if (nblocks >= minlen) {
ret = compat_blkdev_issue_discard(
nilfs->ns_bdev, start * sects_per_block,
nblocks * sects_per_block, GFP_NOFS, 0);
if (!ret)
ndiscarded += nblocks;
}
}
out_sem:
up_read(&NILFS_MDT(sufile)->mi_sem);
range->len = ndiscarded << nilfs->ns_blocksize_bits;
return ret;
}
/* offset in block */
static unsigned long
nilfs_cpfile_get_offset(const struct inode *cpfile, __u64 cno)
{
__u64 tcno = cno + NILFS_MDT(cpfile)->mi_first_entry_offset - 1;
return do_div(tcno, nilfs_cpfile_checkpoints_per_block(cpfile));
}
/**
* nilfs_sufile_updatev - modify multiple segment usages at a time
* @sufile: inode of segment usage file
* @segnumv: array of segment numbers
* @nsegs: size of @segnumv array
* @create: creation flag
* @ndone: place to store number of modified segments on @segnumv
* @dofunc: primitive operation for the update
*
* Description: nilfs_sufile_updatev() repeatedly calls @dofunc
* against the given array of segments. The @dofunc is called with
* buffers of a header block and the sufile block in which the target
* segment usage entry is contained. If @ndone is given, the number
* of successfully modified segments from the head is stored in the
* place @ndone points to.
*
* Return Value: On success, zero is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOENT - Given segment usage is in hole block (may be returned if
* @create is zero)
*
* %-EINVAL - Invalid segment usage number
*/
int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
int create, size_t *ndone,
void (*dofunc)(struct inode *, __u64,
struct buffer_head *,
struct buffer_head *))
{
struct buffer_head *header_bh, *bh;
unsigned long blkoff, prev_blkoff;
__u64 *seg;
size_t nerr = 0, n = 0;
int ret = 0;
if (unlikely(nsegs == 0))
goto out;
down_write(&NILFS_MDT(sufile)->mi_sem);
for (seg = segnumv; seg < segnumv + nsegs; seg++) {
if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
printk(KERN_WARNING
"%s: invalid segment number: %llu\n", __func__,
(unsigned long long)*seg);
nerr++;
}
}
if (nerr > 0) {
ret = -EINVAL;
goto out_sem;
}
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
seg = segnumv;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
dofunc(sufile, *seg, header_bh, bh);
if (++seg >= segnumv + nsegs)
break;
prev_blkoff = blkoff;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
if (blkoff == prev_blkoff)
continue;
/* get different block */
brelse(bh);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (unlikely(ret < 0))
goto out_header;
}
brelse(bh);
out_header:
n = seg - segnumv;
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
out:
if (ndone)
*ndone = n;
return ret;
}
static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
struct nilfs_snapshot_list *list;
__u64 curr, prev;
unsigned long curr_blkoff, prev_blkoff;
void *kaddr;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
if (nilfs_checkpoint_snapshot(cp)) {
ret = 0;
kunmap_atomic(kaddr, KM_USER0);
goto out_cp;
}
kunmap_atomic(kaddr, KM_USER0);
ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
if (ret < 0)
goto out_cp;
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
list = &header->ch_snapshot_list;
curr_bh = header_bh;
get_bh(curr_bh);
curr = 0;
curr_blkoff = 0;
prev = le64_to_cpu(list->ssl_prev);
while (prev > cno) {
prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev);
curr = prev;
if (curr_blkoff != prev_blkoff) {
kunmap_atomic(kaddr, KM_USER0);
brelse(curr_bh);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr,
0, &curr_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(curr_bh->b_page, KM_USER0);
}
curr_blkoff = prev_blkoff;
cp = nilfs_cpfile_block_get_checkpoint(
cpfile, curr, curr_bh, kaddr);
list = &cp->cp_snapshot_list;
prev = le64_to_cpu(list->ssl_prev);
}
kunmap_atomic(kaddr, KM_USER0);
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_curr;
} else {
prev_bh = header_bh;
get_bh(prev_bh);
}
kaddr = kmap_atomic(curr_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, curr, curr_bh, kaddr);
list->ssl_prev = cpu_to_le64(cno);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(cp_bh->b_page, KM_USER0);
cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
cp->cp_snapshot_list.ssl_next = cpu_to_le64(curr);
cp->cp_snapshot_list.ssl_prev = cpu_to_le64(prev);
nilfs_checkpoint_set_snapshot(cp);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(prev_bh->b_page, KM_USER0);
list = nilfs_cpfile_block_get_snapshot_list(
cpfile, prev, prev_bh, kaddr);
list->ssl_next = cpu_to_le64(cno);
kunmap_atomic(kaddr, KM_USER0);
kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
le64_add_cpu(&header->ch_nsnapshots, 1);
kunmap_atomic(kaddr, KM_USER0);
nilfs_mdt_mark_buffer_dirty(prev_bh);
nilfs_mdt_mark_buffer_dirty(curr_bh);
nilfs_mdt_mark_buffer_dirty(cp_bh);
nilfs_mdt_mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
brelse(prev_bh);
out_curr:
brelse(curr_bh);
out_header:
brelse(header_bh);
out_cp:
brelse(cp_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
}
static __u64 nilfs_cpfile_first_checkpoint_in_block(const struct inode *cpfile,
unsigned long blkoff)
{
return (__u64)nilfs_cpfile_checkpoints_per_block(cpfile) * blkoff
+ 1 - NILFS_MDT(cpfile)->mi_first_entry_offset;
}