* [PATCH 08/12] nilfs2: convert checkpoint file to be folio-based
2024-10-24 9:25 [PATCH 00/12] nilfs2: Finish folio conversion Ryusuke Konishi
@ 2024-10-24 9:25 ` Ryusuke Konishi
0 siblings, 0 replies; 2+ messages in thread
From: Ryusuke Konishi @ 2024-10-24 9:25 UTC (permalink / raw)
To: Andrew Morton; +Cc: Matthew Wilcox, linux-nilfs, linux-kernel, linux-fsdevel
Regarding the cpfile, a metadata file that manages checkpoints, convert
the page-based implementation to a folio-based implementation.
This change involves some helper functions to calculate byte offsets on
folios and removing a few helper functions that are no longer needed.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
---
fs/nilfs2/cpfile.c | 379 ++++++++++++++++++++++++---------------------
1 file changed, 204 insertions(+), 175 deletions(-)
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index a8046cbf2753..c20207d7a989 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -68,49 +68,36 @@ static inline int nilfs_cpfile_is_in_first(const struct inode *cpfile,
static unsigned int
nilfs_cpfile_block_add_valid_checkpoints(const struct inode *cpfile,
struct buffer_head *bh,
- void *kaddr,
unsigned int n)
{
- struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
+ struct nilfs_checkpoint *cp;
unsigned int count;
+ cp = kmap_local_folio(bh->b_folio,
+ offset_in_folio(bh->b_folio, bh->b_data));
count = le32_to_cpu(cp->cp_checkpoints_count) + n;
cp->cp_checkpoints_count = cpu_to_le32(count);
+ kunmap_local(cp);
return count;
}
static unsigned int
nilfs_cpfile_block_sub_valid_checkpoints(const struct inode *cpfile,
struct buffer_head *bh,
- void *kaddr,
unsigned int n)
{
- struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
+ struct nilfs_checkpoint *cp;
unsigned int count;
+ cp = kmap_local_folio(bh->b_folio,
+ offset_in_folio(bh->b_folio, bh->b_data));
WARN_ON(le32_to_cpu(cp->cp_checkpoints_count) < n);
count = le32_to_cpu(cp->cp_checkpoints_count) - n;
cp->cp_checkpoints_count = cpu_to_le32(count);
+ kunmap_local(cp);
return count;
}
-static inline struct nilfs_cpfile_header *
-nilfs_cpfile_block_get_header(const struct inode *cpfile,
- struct buffer_head *bh,
- void *kaddr)
-{
- return kaddr + bh_offset(bh);
-}
-
-static struct nilfs_checkpoint *
-nilfs_cpfile_block_get_checkpoint(const struct inode *cpfile, __u64 cno,
- struct buffer_head *bh,
- void *kaddr)
-{
- return kaddr + bh_offset(bh) + nilfs_cpfile_get_offset(cpfile, cno) *
- NILFS_MDT(cpfile)->mi_entry_size;
-}
-
static void nilfs_cpfile_block_init(struct inode *cpfile,
struct buffer_head *bh,
void *from)
@@ -125,6 +112,54 @@ static void nilfs_cpfile_block_init(struct inode *cpfile,
}
}
+/**
+ * nilfs_cpfile_checkpoint_offset - calculate the byte offset of a checkpoint
+ * entry in the folio containing it
+ * @cpfile: checkpoint file inode
+ * @cno: checkpoint number
+ * @bh: buffer head of block containing checkpoint indexed by @cno
+ *
+ * Return: Byte offset in the folio of the checkpoint specified by @cno.
+ */
+static size_t nilfs_cpfile_checkpoint_offset(const struct inode *cpfile,
+ __u64 cno,
+ struct buffer_head *bh)
+{
+ return offset_in_folio(bh->b_folio, bh->b_data) +
+ nilfs_cpfile_get_offset(cpfile, cno) *
+ NILFS_MDT(cpfile)->mi_entry_size;
+}
+
+/**
+ * nilfs_cpfile_cp_snapshot_list_offset - calculate the byte offset of a
+ * checkpoint snapshot list in the folio
+ * containing it
+ * @cpfile: checkpoint file inode
+ * @cno: checkpoint number
+ * @bh: buffer head of block containing checkpoint indexed by @cno
+ *
+ * Return: Byte offset in the folio of the checkpoint snapshot list specified
+ * by @cno.
+ */
+static size_t nilfs_cpfile_cp_snapshot_list_offset(const struct inode *cpfile,
+ __u64 cno,
+ struct buffer_head *bh)
+{
+ return nilfs_cpfile_checkpoint_offset(cpfile, cno, bh) +
+ offsetof(struct nilfs_checkpoint, cp_snapshot_list);
+}
+
+/**
+ * nilfs_cpfile_ch_snapshot_list_offset - calculate the byte offset of the
+ * snapshot list in the header
+ *
+ * Return: Byte offset in the folio of the checkpoint snapshot list
+ */
+static size_t nilfs_cpfile_ch_snapshot_list_offset(void)
+{
+ return offsetof(struct nilfs_cpfile_header, ch_snapshot_list);
+}
+
static int nilfs_cpfile_get_header_block(struct inode *cpfile,
struct buffer_head **bhp)
{
@@ -214,7 +249,7 @@ int nilfs_cpfile_read_checkpoint(struct inode *cpfile, __u64 cno,
{
struct buffer_head *cp_bh;
struct nilfs_checkpoint *cp;
- void *kaddr;
+ size_t offset;
int ret;
if (cno < 1 || cno > nilfs_mdt_cno(cpfile))
@@ -228,8 +263,8 @@ int nilfs_cpfile_read_checkpoint(struct inode *cpfile, __u64 cno,
goto out_sem;
}
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
if (nilfs_checkpoint_invalid(cp)) {
ret = -EINVAL;
goto put_cp;
@@ -254,7 +289,7 @@ int nilfs_cpfile_read_checkpoint(struct inode *cpfile, __u64 cno,
root->ifile = ifile;
put_cp:
- kunmap_local(kaddr);
+ kunmap_local(cp);
brelse(cp_bh);
out_sem:
up_read(&NILFS_MDT(cpfile)->mi_sem);
@@ -282,7 +317,7 @@ int nilfs_cpfile_create_checkpoint(struct inode *cpfile, __u64 cno)
struct buffer_head *header_bh, *cp_bh;
struct nilfs_cpfile_header *header;
struct nilfs_checkpoint *cp;
- void *kaddr;
+ size_t offset;
int ret;
if (WARN_ON_ONCE(cno < 1))
@@ -297,24 +332,22 @@ int nilfs_cpfile_create_checkpoint(struct inode *cpfile, __u64 cno)
if (unlikely(ret < 0))
goto out_header;
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
if (nilfs_checkpoint_invalid(cp)) {
/* a newly-created checkpoint */
nilfs_checkpoint_clear_invalid(cp);
+ kunmap_local(cp);
if (!nilfs_cpfile_is_in_first(cpfile, cno))
nilfs_cpfile_block_add_valid_checkpoints(cpfile, cp_bh,
- kaddr, 1);
- kunmap_local(kaddr);
+ 1);
- kaddr = kmap_local_page(header_bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, header_bh,
- kaddr);
+ header = kmap_local_folio(header_bh->b_folio, 0);
le64_add_cpu(&header->ch_ncheckpoints, 1);
- kunmap_local(kaddr);
+ kunmap_local(header);
mark_buffer_dirty(header_bh);
} else {
- kunmap_local(kaddr);
+ kunmap_local(cp);
}
/* Force the buffer and the inode to become dirty */
@@ -353,7 +386,7 @@ int nilfs_cpfile_finalize_checkpoint(struct inode *cpfile, __u64 cno,
{
struct buffer_head *cp_bh;
struct nilfs_checkpoint *cp;
- void *kaddr;
+ size_t offset;
int ret;
if (WARN_ON_ONCE(cno < 1))
@@ -367,10 +400,10 @@ int nilfs_cpfile_finalize_checkpoint(struct inode *cpfile, __u64 cno,
goto out_sem;
}
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
if (unlikely(nilfs_checkpoint_invalid(cp))) {
- kunmap_local(kaddr);
+ kunmap_local(cp);
brelse(cp_bh);
goto error;
}
@@ -391,7 +424,7 @@ int nilfs_cpfile_finalize_checkpoint(struct inode *cpfile, __u64 cno,
nilfs_write_inode_common(root->ifile, &cp->cp_ifile_inode);
nilfs_bmap_write(NILFS_I(root->ifile)->i_bmap, &cp->cp_ifile_inode);
- kunmap_local(kaddr);
+ kunmap_local(cp);
brelse(cp_bh);
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
@@ -432,6 +465,7 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
struct nilfs_checkpoint *cp;
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
__u64 cno;
+ size_t offset;
void *kaddr;
unsigned long tnicps;
int ret, ncps, nicps, nss, count, i;
@@ -462,9 +496,8 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
continue;
}
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(
- cpfile, cno, cp_bh, kaddr);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kaddr = kmap_local_folio(cp_bh->b_folio, offset);
nicps = 0;
for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
if (nilfs_checkpoint_snapshot(cp)) {
@@ -474,43 +507,42 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
nicps++;
}
}
- if (nicps > 0) {
- tnicps += nicps;
- 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_local(kaddr);
- brelse(cp_bh);
- ret =
- nilfs_cpfile_delete_checkpoint_block(
- cpfile, cno);
- if (ret == 0)
- continue;
- nilfs_err(cpfile->i_sb,
- "error %d deleting checkpoint block",
- ret);
- break;
- }
- }
+ kunmap_local(kaddr);
+
+ if (nicps <= 0) {
+ brelse(cp_bh);
+ continue;
}
- kunmap_local(kaddr);
+ tnicps += nicps;
+ mark_buffer_dirty(cp_bh);
+ nilfs_mdt_mark_dirty(cpfile);
+ if (nilfs_cpfile_is_in_first(cpfile, cno)) {
+ brelse(cp_bh);
+ continue;
+ }
+
+ count = nilfs_cpfile_block_sub_valid_checkpoints(cpfile, cp_bh,
+ nicps);
brelse(cp_bh);
+ if (count)
+ continue;
+
+ /* Delete the block if there are no more valid checkpoints */
+ ret = nilfs_cpfile_delete_checkpoint_block(cpfile, cno);
+ if (unlikely(ret)) {
+ nilfs_err(cpfile->i_sb,
+ "error %d deleting checkpoint block", ret);
+ break;
+ }
}
if (tnicps > 0) {
- kaddr = kmap_local_page(header_bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, header_bh,
- kaddr);
+ header = kmap_local_folio(header_bh->b_folio, 0);
le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps);
mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(cpfile);
- kunmap_local(kaddr);
+ kunmap_local(header);
}
brelse(header_bh);
@@ -544,6 +576,7 @@ static ssize_t nilfs_cpfile_do_get_cpinfo(struct inode *cpfile, __u64 *cnop,
struct buffer_head *bh;
size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
__u64 cur_cno = nilfs_mdt_cno(cpfile), cno = *cnop;
+ size_t offset;
void *kaddr;
int n, ret;
int ncps, i;
@@ -562,8 +595,8 @@ static ssize_t nilfs_cpfile_do_get_cpinfo(struct inode *cpfile, __u64 *cnop,
}
ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, cur_cno);
- kaddr = kmap_local_page(bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, bh);
+ cp = kaddr = kmap_local_folio(bh->b_folio, offset);
for (i = 0; i < ncps && n < nci; i++, cp = (void *)cp + cpsz) {
if (!nilfs_checkpoint_invalid(cp)) {
nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp,
@@ -597,7 +630,7 @@ static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
struct nilfs_cpinfo *ci = buf;
__u64 curr = *cnop, next;
unsigned long curr_blkoff, next_blkoff;
- void *kaddr;
+ size_t offset;
int n = 0, ret;
down_read(&NILFS_MDT(cpfile)->mi_sem);
@@ -606,10 +639,9 @@ static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
ret = nilfs_cpfile_get_header_block(cpfile, &bh);
if (ret < 0)
goto out;
- kaddr = kmap_local_page(bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
+ header = kmap_local_folio(bh->b_folio, 0);
curr = le64_to_cpu(header->ch_snapshot_list.ssl_next);
- kunmap_local(kaddr);
+ kunmap_local(header);
brelse(bh);
if (curr == 0) {
ret = 0;
@@ -627,9 +659,9 @@ static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
ret = 0; /* No snapshots (started from a hole block) */
goto out;
}
- kaddr = kmap_local_page(bh->b_page);
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, curr, bh);
+ cp = kmap_local_folio(bh->b_folio, offset);
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)))
@@ -641,9 +673,9 @@ static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
if (next == 0)
break; /* reach end of the snapshot list */
+ kunmap_local(cp);
next_blkoff = nilfs_cpfile_get_blkoff(cpfile, next);
if (curr_blkoff != next_blkoff) {
- kunmap_local(kaddr);
brelse(bh);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, next,
0, &bh);
@@ -651,12 +683,13 @@ static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
WARN_ON(ret == -ENOENT);
goto out;
}
- kaddr = kmap_local_page(bh->b_page);
}
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, next, bh);
+ cp = kmap_local_folio(bh->b_folio, offset);
curr = next;
curr_blkoff = next_blkoff;
}
- kunmap_local(kaddr);
+ kunmap_local(cp);
brelse(bh);
*cnop = curr;
ret = n;
@@ -733,26 +766,6 @@ int nilfs_cpfile_delete_checkpoint(struct inode *cpfile, __u64 cno)
return nilfs_cpfile_delete_checkpoints(cpfile, cno, cno + 1);
}
-static struct nilfs_snapshot_list *
-nilfs_cpfile_block_get_snapshot_list(const struct inode *cpfile,
- __u64 cno,
- struct buffer_head *bh,
- void *kaddr)
-{
- struct nilfs_cpfile_header *header;
- struct nilfs_checkpoint *cp;
- struct nilfs_snapshot_list *list;
-
- if (cno != 0) {
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
- list = &cp->cp_snapshot_list;
- } else {
- header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
- list = &header->ch_snapshot_list;
- }
- return list;
-}
-
static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh;
@@ -761,94 +774,103 @@ static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
struct nilfs_snapshot_list *list;
__u64 curr, prev;
unsigned long curr_blkoff, prev_blkoff;
- void *kaddr;
+ size_t offset, curr_list_offset, prev_list_offset;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
+ ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
+ if (unlikely(ret < 0))
+ goto out_sem;
+
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
- goto out_sem;
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ goto out_header;
+
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
- kunmap_local(kaddr);
+ kunmap_local(cp);
goto out_cp;
}
if (nilfs_checkpoint_snapshot(cp)) {
ret = 0;
- kunmap_local(kaddr);
+ kunmap_local(cp);
goto out_cp;
}
- kunmap_local(kaddr);
+ kunmap_local(cp);
- ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
- if (ret < 0)
- goto out_cp;
- kaddr = kmap_local_page(header_bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
+ /*
+ * Find the last snapshot before the checkpoint being changed to
+ * snapshot mode by going backwards through the snapshot list.
+ * Set "prev" to its checkpoint number, or 0 if not found.
+ */
+ header = kmap_local_folio(header_bh->b_folio, 0);
list = &header->ch_snapshot_list;
curr_bh = header_bh;
get_bh(curr_bh);
curr = 0;
curr_blkoff = 0;
+ curr_list_offset = nilfs_cpfile_ch_snapshot_list_offset();
prev = le64_to_cpu(list->ssl_prev);
while (prev > cno) {
prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev);
curr = prev;
+ kunmap_local(list);
if (curr_blkoff != prev_blkoff) {
- kunmap_local(kaddr);
brelse(curr_bh);
ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr,
0, &curr_bh);
- if (ret < 0)
- goto out_header;
- kaddr = kmap_local_page(curr_bh->b_page);
+ if (unlikely(ret < 0))
+ goto out_cp;
}
+ curr_list_offset = nilfs_cpfile_cp_snapshot_list_offset(
+ cpfile, curr, curr_bh);
+ list = kmap_local_folio(curr_bh->b_folio, curr_list_offset);
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_local(kaddr);
+ kunmap_local(list);
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_curr;
+
+ prev_list_offset = nilfs_cpfile_cp_snapshot_list_offset(
+ cpfile, prev, prev_bh);
} else {
prev_bh = header_bh;
get_bh(prev_bh);
+ prev_list_offset = nilfs_cpfile_ch_snapshot_list_offset();
}
- kaddr = kmap_local_page(curr_bh->b_page);
- list = nilfs_cpfile_block_get_snapshot_list(
- cpfile, curr, curr_bh, kaddr);
+ /* Update the list entry for the next snapshot */
+ list = kmap_local_folio(curr_bh->b_folio, curr_list_offset);
list->ssl_prev = cpu_to_le64(cno);
- kunmap_local(kaddr);
+ kunmap_local(list);
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ /* Update the checkpoint being changed to a snapshot */
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
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_local(kaddr);
+ kunmap_local(cp);
- kaddr = kmap_local_page(prev_bh->b_page);
- list = nilfs_cpfile_block_get_snapshot_list(
- cpfile, prev, prev_bh, kaddr);
+ /* Update the list entry for the previous snapshot */
+ list = kmap_local_folio(prev_bh->b_folio, prev_list_offset);
list->ssl_next = cpu_to_le64(cno);
- kunmap_local(kaddr);
+ kunmap_local(list);
- kaddr = kmap_local_page(header_bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
+ /* Update the statistics in the header */
+ header = kmap_local_folio(header_bh->b_folio, 0);
le64_add_cpu(&header->ch_nsnapshots, 1);
- kunmap_local(kaddr);
+ kunmap_local(header);
mark_buffer_dirty(prev_bh);
mark_buffer_dirty(curr_bh);
@@ -861,12 +883,12 @@ static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
out_curr:
brelse(curr_bh);
- out_header:
- brelse(header_bh);
-
out_cp:
brelse(cp_bh);
+ out_header:
+ brelse(header_bh);
+
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
@@ -879,79 +901,87 @@ static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno)
struct nilfs_checkpoint *cp;
struct nilfs_snapshot_list *list;
__u64 next, prev;
- void *kaddr;
+ size_t offset, next_list_offset, prev_list_offset;
int ret;
if (cno == 0)
return -ENOENT; /* checkpoint number 0 is invalid */
down_write(&NILFS_MDT(cpfile)->mi_sem);
+ ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
+ if (unlikely(ret < 0))
+ goto out_sem;
+
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
if (ret < 0)
- goto out_sem;
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ goto out_header;
+
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, cp_bh);
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
if (nilfs_checkpoint_invalid(cp)) {
ret = -ENOENT;
- kunmap_local(kaddr);
+ kunmap_local(cp);
goto out_cp;
}
if (!nilfs_checkpoint_snapshot(cp)) {
ret = 0;
- kunmap_local(kaddr);
+ kunmap_local(cp);
goto out_cp;
}
list = &cp->cp_snapshot_list;
next = le64_to_cpu(list->ssl_next);
prev = le64_to_cpu(list->ssl_prev);
- kunmap_local(kaddr);
+ kunmap_local(cp);
- 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;
+ goto out_cp;
+
+ next_list_offset = nilfs_cpfile_cp_snapshot_list_offset(
+ cpfile, next, next_bh);
} else {
next_bh = header_bh;
get_bh(next_bh);
+ next_list_offset = nilfs_cpfile_ch_snapshot_list_offset();
}
if (prev != 0) {
ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
&prev_bh);
if (ret < 0)
goto out_next;
+
+ prev_list_offset = nilfs_cpfile_cp_snapshot_list_offset(
+ cpfile, prev, prev_bh);
} else {
prev_bh = header_bh;
get_bh(prev_bh);
+ prev_list_offset = nilfs_cpfile_ch_snapshot_list_offset();
}
- kaddr = kmap_local_page(next_bh->b_page);
- list = nilfs_cpfile_block_get_snapshot_list(
- cpfile, next, next_bh, kaddr);
+ /* Update the list entry for the next snapshot */
+ list = kmap_local_folio(next_bh->b_folio, next_list_offset);
list->ssl_prev = cpu_to_le64(prev);
- kunmap_local(kaddr);
+ kunmap_local(list);
- kaddr = kmap_local_page(prev_bh->b_page);
- list = nilfs_cpfile_block_get_snapshot_list(
- cpfile, prev, prev_bh, kaddr);
+ /* Update the list entry for the previous snapshot */
+ list = kmap_local_folio(prev_bh->b_folio, prev_list_offset);
list->ssl_next = cpu_to_le64(next);
- kunmap_local(kaddr);
+ kunmap_local(list);
- kaddr = kmap_local_page(cp_bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
+ /* Update the snapshot being changed back to a plain checkpoint */
+ cp = kmap_local_folio(cp_bh->b_folio, offset);
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_local(kaddr);
+ kunmap_local(cp);
- kaddr = kmap_local_page(header_bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
+ /* Update the statistics in the header */
+ header = kmap_local_folio(header_bh->b_folio, 0);
le64_add_cpu(&header->ch_nsnapshots, -1);
- kunmap_local(kaddr);
+ kunmap_local(header);
mark_buffer_dirty(next_bh);
mark_buffer_dirty(prev_bh);
@@ -964,12 +994,12 @@ static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno)
out_next:
brelse(next_bh);
- out_header:
- brelse(header_bh);
-
out_cp:
brelse(cp_bh);
+ out_header:
+ brelse(header_bh);
+
out_sem:
up_write(&NILFS_MDT(cpfile)->mi_sem);
return ret;
@@ -990,7 +1020,7 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno)
{
struct buffer_head *bh;
struct nilfs_checkpoint *cp;
- void *kaddr;
+ size_t offset;
int ret;
/*
@@ -1004,13 +1034,14 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno)
ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh);
if (ret < 0)
goto out;
- kaddr = kmap_local_page(bh->b_page);
- cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
+
+ offset = nilfs_cpfile_checkpoint_offset(cpfile, cno, bh);
+ cp = kmap_local_folio(bh->b_folio, offset);
if (nilfs_checkpoint_invalid(cp))
ret = -ENOENT;
else
ret = nilfs_checkpoint_snapshot(cp);
- kunmap_local(kaddr);
+ kunmap_local(cp);
brelse(bh);
out:
@@ -1079,7 +1110,6 @@ int nilfs_cpfile_get_stat(struct inode *cpfile, struct nilfs_cpstat *cpstat)
{
struct buffer_head *bh;
struct nilfs_cpfile_header *header;
- void *kaddr;
int ret;
down_read(&NILFS_MDT(cpfile)->mi_sem);
@@ -1087,12 +1117,11 @@ int nilfs_cpfile_get_stat(struct inode *cpfile, struct nilfs_cpstat *cpstat)
ret = nilfs_cpfile_get_header_block(cpfile, &bh);
if (ret < 0)
goto out_sem;
- kaddr = kmap_local_page(bh->b_page);
- header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
+ header = kmap_local_folio(bh->b_folio, 0);
cpstat->cs_cno = nilfs_mdt_cno(cpfile);
cpstat->cs_ncps = le64_to_cpu(header->ch_ncheckpoints);
cpstat->cs_nsss = le64_to_cpu(header->ch_nsnapshots);
- kunmap_local(kaddr);
+ kunmap_local(header);
brelse(bh);
out_sem:
--
2.43.0
^ permalink raw reply related [flat|nested] 2+ messages in thread