diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index a7f5bc724e337ad42fa269fe8d7b772f732edf24..19af5ab862751a7ff7860416427f1355adba49b2 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -275,13 +275,10 @@ extern void nilfs_error(struct super_block *, const char *, const char *, ...)
extern void nilfs_warning(struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern struct nilfs_super_block *
-nilfs_load_super_block(struct super_block *, struct buffer_head **);
-extern struct nilfs_super_block *
-nilfs_reload_super_block(struct super_block *, struct buffer_head **, int);
+nilfs_read_super_block(struct super_block *, u64, int, struct buffer_head **);
extern int nilfs_store_magic_and_option(struct super_block *,
struct nilfs_super_block *, char *);
-extern void nilfs_update_last_segment(struct nilfs_sb_info *, int);
-extern int nilfs_commit_super(struct nilfs_sb_info *);
+extern int nilfs_commit_super(struct nilfs_sb_info *, int);
extern int nilfs_attach_checkpoint(struct nilfs_sb_info *, __u64);
extern void nilfs_detach_checkpoint(struct nilfs_sb_info *);
diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c
index 6ab4c8fc5e9fbb88bd1aaef96bd069a163e3dd1e..6ade0963fc1d8a29459596db127d9c6797d7e4fa 100644
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -870,7 +870,6 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
if (scan_newer)
ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED;
else {
- nilfs->ns_prot_seq = ssi.seg_seq;
if (nilfs->ns_mount_state & NILFS_VALID_FS)
goto super_root_found;
scan_newer = 1;
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index e43558d50e78b908ce97cc909adb99a86f50b387..fb70ec3be20ea0899d34e98a4a48b9828b358052 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2068,7 +2068,8 @@ static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
if (update_sr) {
nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start,
- segbuf->sb_sum.seg_seq, nilfs->ns_cno);
+ segbuf->sb_sum.seg_seq, nilfs->ns_cno++);
+ sbi->s_super->s_dirt = 1;
clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags);
clear_bit(NILFS_SC_DIRTY, &sci->sc_flags);
@@ -2224,9 +2225,6 @@ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
/* Commit segments */
if (has_sr) {
- down_write(&nilfs->ns_sem);
- nilfs_update_last_segment(sbi, 1);
- up_write(&nilfs->ns_sem);
nilfs_segctor_commit_free_segments(sci);
nilfs_segctor_clear_metadata_dirty(sci);
}
@@ -2564,7 +2562,7 @@ static int nilfs_segctor_construct(struct nilfs_sc_info *sci,
if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) &&
nilfs_discontinued(nilfs)) {
down_write(&nilfs->ns_sem);
- req->sb_err = nilfs_commit_super(sbi);
+ req->sb_err = nilfs_commit_super(sbi, 0);
up_write(&nilfs->ns_sem);
}
}
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index 4a64eb82f1f56a3d71a06e330b2dbdd194cc6c17..a98fc1ed0bbb9ac4bf4e321612fe21072aedbbfe 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -206,8 +206,6 @@ enum {
logical segment with a super root */
#define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root
creation */
-#define NILFS_SC_DEFAULT_SB_FREQ 30 /* Minimum interval of periodical
- update of superblock (reserved) */
/*
* The default threshold amount of data, in block counts.
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index ef31e9a51c845404cc9df852d5920cf99b4c670b..e2ced824c6243492737a37764b5b22d64fac67e0 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -103,8 +103,9 @@ void nilfs_error(struct super_block *sb, const char *function,
down_write(&nilfs->ns_sem);
if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
nilfs->ns_mount_state |= NILFS_ERROR_FS;
- nilfs->ns_sbp->s_state |= cpu_to_le16(NILFS_ERROR_FS);
- nilfs_commit_super(sbi);
+ nilfs->ns_sbp[0]->s_state |=
+ cpu_to_le16(NILFS_ERROR_FS);
+ nilfs_commit_super(sbi, 1);
}
up_write(&nilfs->ns_sem);
@@ -208,90 +209,106 @@ static void nilfs_clear_inode(struct inode *inode)
nilfs_btnode_cache_clear(&ii->i_btnode_cache);
}
-/**
- * nilfs_update_last_segment - change pointer to the latest segment
- * @sbi: nilfs_sb_info
- * @update_cno: flag whether to update checkpoint number.
- *
- * nilfs_update_last_segment() changes information in the super block
- * after a partial segment is written out successfully. The super
- * block is marked dirty. It will be written out at the next VFS sync
- * operations such as sync_supers() and generic_shutdown_super().
- */
-void nilfs_update_last_segment(struct nilfs_sb_info *sbi, int update_cno)
-{
- struct the_nilfs *nilfs = sbi->s_nilfs;
- struct nilfs_super_block *sbp = nilfs->ns_sbp;
-
- /* nilfs->sem must be locked by the caller. */
- spin_lock(&nilfs->ns_last_segment_lock);
- if (update_cno)
- nilfs->ns_last_cno = nilfs->ns_cno++;
- sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
- sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
- sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
- spin_unlock(&nilfs->ns_last_segment_lock);
-
- sbi->s_super->s_dirt = 1; /* must be set if delaying the call of
- nilfs_commit_super() */
-}
-
-static int nilfs_sync_super(struct nilfs_sb_info *sbi)
+static int nilfs_sync_super(struct nilfs_sb_info *sbi, int dupsb)
{
struct the_nilfs *nilfs = sbi->s_nilfs;
int err;
int barrier_done = 0;
if (nilfs_test_opt(sbi, BARRIER)) {
- set_buffer_ordered(nilfs->ns_sbh);
+ set_buffer_ordered(nilfs->ns_sbh[0]);
barrier_done = 1;
}
retry:
- set_buffer_dirty(nilfs->ns_sbh);
- err = sync_dirty_buffer(nilfs->ns_sbh);
+ set_buffer_dirty(nilfs->ns_sbh[0]);
+ err = sync_dirty_buffer(nilfs->ns_sbh[0]);
if (err == -EOPNOTSUPP && barrier_done) {
nilfs_warning(sbi->s_super, __func__,
"barrier-based sync failed. "
"disabling barriers\n");
nilfs_clear_opt(sbi, BARRIER);
barrier_done = 0;
- clear_buffer_ordered(nilfs->ns_sbh);
+ clear_buffer_ordered(nilfs->ns_sbh[0]);
goto retry;
}
- if (unlikely(err))
+ if (unlikely(err)) {
printk(KERN_ERR
"NILFS: unable to write superblock (err=%d)\n", err);
- else {
+ if (err == -EIO && nilfs->ns_sbh[1]) {
+ nilfs_fall_back_super_block(nilfs);
+ goto retry;
+ }
+ } else {
+ struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
+
+ /*
+ * The latest segment becomes trailable from the position
+ * written in superblock.
+ */
clear_nilfs_discontinued(nilfs);
- spin_lock(&nilfs->ns_last_segment_lock);
- nilfs->ns_prot_seq = le64_to_cpu(nilfs->ns_sbp->s_last_seq);
- spin_unlock(&nilfs->ns_last_segment_lock);
+
+ /* update GC protection for recent segments */
+ if (nilfs->ns_sbh[1]) {
+ sbp = NULL;
+ if (dupsb) {
+ set_buffer_dirty(nilfs->ns_sbh[1]);
+ if (!sync_dirty_buffer(nilfs->ns_sbh[1]))
+ sbp = nilfs->ns_sbp[1];
+ }
+ }
+ if (sbp) {
+ spin_lock(&nilfs->ns_last_segment_lock);
+ nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
+ spin_unlock(&nilfs->ns_last_segment_lock);
+ }
}
return err;
}
-int nilfs_commit_super(struct nilfs_sb_info *sbi)
+int nilfs_commit_super(struct nilfs_sb_info *sbi, int dupsb)
{
struct the_nilfs *nilfs = sbi->s_nilfs;
- struct nilfs_super_block *sbp = nilfs->ns_sbp;
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
sector_t nfreeblocks;
+ time_t t;
int err;
/* nilfs->sem must be locked by the caller. */
+ if (sbp[0]->s_magic != NILFS_SUPER_MAGIC) {
+ if (sbp[1] && sbp[1]->s_magic == NILFS_SUPER_MAGIC)
+ nilfs_swap_super_block(nilfs);
+ else {
+ printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
+ sbi->s_super->s_id);
+ return -EIO;
+ }
+ }
err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
if (unlikely(err)) {
printk(KERN_ERR "NILFS: failed to count free blocks\n");
return err;
}
- sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
- sbp->s_wtime = cpu_to_le64(get_seconds());
- sbp->s_sum = 0;
- sbp->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
- (unsigned char *)sbp,
- le16_to_cpu(sbp->s_bytes)));
+ spin_lock(&nilfs->ns_last_segment_lock);
+ sbp[0]->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
+ sbp[0]->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
+ sbp[0]->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
+ spin_unlock(&nilfs->ns_last_segment_lock);
+
+ t = get_seconds();
+ nilfs->ns_sbwtime[0] = t;
+ sbp[0]->s_free_blocks_count = cpu_to_le64(nfreeblocks);
+ sbp[0]->s_wtime = cpu_to_le64(t);
+ sbp[0]->s_sum = 0;
+ sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
+ (unsigned char *)sbp[0],
+ nilfs->ns_sbsize));
+ if (dupsb && sbp[1]) {
+ memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
+ nilfs->ns_sbwtime[1] = t;
+ }
sbi->s_super->s_dirt = 0;
- return nilfs_sync_super(sbi);
+ return nilfs_sync_super(sbi, dupsb);
}
static void nilfs_put_super(struct super_block *sb)
@@ -303,8 +320,8 @@ static void nilfs_put_super(struct super_block *sb)
if (!(sb->s_flags & MS_RDONLY)) {
down_write(&nilfs->ns_sem);
- nilfs->ns_sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
- nilfs_commit_super(sbi);
+ nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
+ nilfs_commit_super(sbi, 1);
up_write(&nilfs->ns_sem);
}
@@ -330,7 +347,7 @@ static void nilfs_put_super(struct super_block *sb)
* 2. down_write(&nilfs->ns_sem)
*
* Inside NILFS, locking ns_sem is enough to protect s_dirt and the buffer
- * of the super block (nilfs->ns_sbp).
+ * of the super block (nilfs->ns_sbp[]).
*
* In most cases, VFS functions call lock_super() before calling these
* methods. So we must be careful not to bring on deadlocks when using
@@ -346,8 +363,19 @@ static void nilfs_write_super(struct super_block *sb)
struct the_nilfs *nilfs = sbi->s_nilfs;
down_write(&nilfs->ns_sem);
- if (!(sb->s_flags & MS_RDONLY))
- nilfs_commit_super(sbi);
+ if (!(sb->s_flags & MS_RDONLY)) {
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
+ u64 t = get_seconds();
+ int dupsb;
+
+ if (!nilfs_discontinued(nilfs) && t >= nilfs->ns_sbwtime[0] &&
+ t < nilfs->ns_sbwtime[0] + NILFS_SB_FREQ) {
+ up_write(&nilfs->ns_sem);
+ return;
+ }
+ dupsb = sbp[1] && t > nilfs->ns_sbwtime[1] + NILFS_ALTSB_FREQ;
+ nilfs_commit_super(sbi, dupsb);
+ }
sb->s_dirt = 0;
up_write(&nilfs->ns_sem);
}
@@ -436,7 +464,7 @@ static int nilfs_mark_recovery_complete(struct nilfs_sb_info *sbi)
down_write(&nilfs->ns_sem);
if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) {
nilfs->ns_mount_state |= NILFS_VALID_FS;
- err = nilfs_commit_super(sbi);
+ err = nilfs_commit_super(sbi, 1);
if (likely(!err))
printk(KERN_INFO "NILFS: recovery complete.\n");
}
@@ -652,7 +680,7 @@ nilfs_set_default_options(struct nilfs_sb_info *sbi,
static int nilfs_setup_super(struct nilfs_sb_info *sbi)
{
struct the_nilfs *nilfs = sbi->s_nilfs;
- struct nilfs_super_block *sbp = nilfs->ns_sbp;
+ struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
int max_mnt_count = le16_to_cpu(sbp->s_max_mnt_count);
int mnt_count = le16_to_cpu(sbp->s_mnt_count);
@@ -674,88 +702,29 @@ static int nilfs_setup_super(struct nilfs_sb_info *sbi)
sbp->s_mnt_count = cpu_to_le16(mnt_count + 1);
sbp->s_state = cpu_to_le16(le16_to_cpu(sbp->s_state) & ~NILFS_VALID_FS);
sbp->s_mtime = cpu_to_le64(get_seconds());
- return nilfs_commit_super(sbi);
+ return nilfs_commit_super(sbi, 1);
}
-struct nilfs_super_block *
-nilfs_load_super_block(struct super_block *sb, struct buffer_head **pbh)
+struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
+ u64 pos, int blocksize,
+ struct buffer_head **pbh)
{
- int blocksize;
- unsigned long offset, sb_index;
-
- /*
- * Adjusting block size
- * Blocksize will be enlarged when it is smaller than hardware
- * sector size.
- * Disk format of superblock does not change.
- */
- blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
- if (!blocksize) {
- printk(KERN_ERR
- "NILFS: unable to set blocksize of superblock\n");
- return NULL;
- }
- sb_index = NILFS_SB_OFFSET_BYTES / blocksize;
- offset = NILFS_SB_OFFSET_BYTES % blocksize;
+ unsigned long long sb_index = pos;
+ unsigned long offset;
+ offset = do_div(sb_index, blocksize);
*pbh = sb_bread(sb, sb_index);
- if (!*pbh) {
- printk(KERN_ERR "NILFS: unable to read superblock\n");
+ if (!*pbh)
return NULL;
- }
return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
}
-struct nilfs_super_block *
-nilfs_reload_super_block(struct super_block *sb, struct buffer_head **pbh,
- int blocksize)
-{
- struct nilfs_super_block *sbp;
- unsigned long offset, sb_index;
- int hw_blocksize = bdev_hardsect_size(sb->s_bdev);
-
- if (blocksize < hw_blocksize) {
- printk(KERN_ERR
- "NILFS: blocksize %d too small for device "
- "(sector-size = %d).\n",
- blocksize, hw_blocksize);
- goto failed_sbh;
- }
- brelse(*pbh);
- sb_set_blocksize(sb, blocksize);
-
- sb_index = NILFS_SB_OFFSET_BYTES / blocksize;
- offset = NILFS_SB_OFFSET_BYTES % blocksize;
-
- *pbh = sb_bread(sb, sb_index);
- if (!*pbh) {
- printk(KERN_ERR
- "NILFS: cannot read superblock on 2nd try.\n");
- goto failed;
- }
-
- sbp = (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
- if (sbp->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
- printk(KERN_ERR
- "NILFS: !? Magic mismatch on 2nd try.\n");
- goto failed_sbh;
- }
- return sbp;
-
- failed_sbh:
- brelse(*pbh);
-
- failed:
- return NULL;
-}
-
int nilfs_store_magic_and_option(struct super_block *sb,
struct nilfs_super_block *sbp,
char *data)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
- /* trying to fill super (1st stage) */
sb->s_magic = le16_to_cpu(sbp->s_magic);
/* FS independent flags */
@@ -763,11 +732,6 @@ int nilfs_store_magic_and_option(struct super_block *sb,
sb->s_flags |= MS_NOATIME;
#endif
- if (sb->s_magic != NILFS_SUPER_MAGIC) {
- printk("NILFS: Can't find nilfs on dev %s.\n", sb->s_id);
- return -EINVAL;
- }
-
nilfs_set_default_options(sbi, sbp);
sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
@@ -775,10 +739,7 @@ int nilfs_store_magic_and_option(struct super_block *sb,
sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
- if (!parse_options(data, sb))
- return -EINVAL;
-
- return 0;
+ return !parse_options(data, sb) ? -EINVAL : 0 ;
}
/**
@@ -967,12 +928,12 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
* the RDONLY flag and then mark the partition as valid again.
*/
down_write(&nilfs->ns_sem);
- sbp = nilfs->ns_sbp;
+ sbp = nilfs->ns_sbp[0];
if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
(nilfs->ns_mount_state & NILFS_VALID_FS))
sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
sbp->s_mtime = cpu_to_le64(get_seconds());
- nilfs_commit_super(sbi);
+ nilfs_commit_super(sbi, 1);
up_write(&nilfs->ns_sem);
} else {
/*
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 661ab762d765401e235f708726301f7094b4e5f5..33400cf0bbe26529ab4f2bddef42098d1a18d67e 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -25,6 +25,7 @@
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
+#include <linux/crc32.h>
#include "nilfs.h"
#include "segment.h"
#include "alloc.h"
@@ -105,7 +106,8 @@ void put_nilfs(struct the_nilfs *nilfs)
}
if (nilfs_init(nilfs)) {
nilfs_destroy_gccache(nilfs);
- brelse(nilfs->ns_sbh);
+ brelse(nilfs->ns_sbh[0]);
+ brelse(nilfs->ns_sbh[1]);
}
kfree(nilfs);
}
@@ -115,6 +117,7 @@ static int nilfs_load_super_root(struct the_nilfs *nilfs,
{
struct buffer_head *bh_sr;
struct nilfs_super_root *raw_sr;
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
unsigned dat_entry_size, segment_usage_size, checkpoint_size;
unsigned inode_size;
int err;
@@ -124,9 +127,9 @@ static int nilfs_load_super_root(struct the_nilfs *nilfs,
return err;
down_read(&nilfs->ns_sem);
- dat_entry_size = le16_to_cpu(nilfs->ns_sbp->s_dat_entry_size);
- checkpoint_size = le16_to_cpu(nilfs->ns_sbp->s_checkpoint_size);
- segment_usage_size = le16_to_cpu(nilfs->ns_sbp->s_segment_usage_size);
+ dat_entry_size = le16_to_cpu(sbp[0]->s_dat_entry_size);
+ checkpoint_size = le16_to_cpu(sbp[0]->s_checkpoint_size);
+ segment_usage_size = le16_to_cpu(sbp[0]->s_segment_usage_size);
up_read(&nilfs->ns_sem);
inode_size = nilfs->ns_inode_size;
@@ -270,11 +273,8 @@ int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
nilfs_mdt_destroy(nilfs->ns_dat);
goto failed;
}
- if (ri.ri_need_recovery == NILFS_RECOVERY_SR_UPDATED) {
- down_write(&nilfs->ns_sem);
- nilfs_update_last_segment(sbi, 0);
- up_write(&nilfs->ns_sem);
- }
+ if (ri.ri_need_recovery == NILFS_RECOVERY_SR_UPDATED)
+ sbi->s_super->s_dirt = 1;
}
set_nilfs_loaded(nilfs);
@@ -296,9 +296,8 @@ static unsigned long long nilfs_max_size(unsigned int blkbits)
return res;
}
-static int
-nilfs_store_disk_layout(struct the_nilfs *nilfs, struct super_block *sb,
- struct nilfs_super_block *sbp)
+static int nilfs_store_disk_layout(struct the_nilfs *nilfs,
+ struct nilfs_super_block *sbp)
{
if (le32_to_cpu(sbp->s_rev_level) != NILFS_CURRENT_REV) {
printk(KERN_ERR "NILFS: revision mismatch "
@@ -309,6 +308,10 @@ nilfs_store_disk_layout(struct the_nilfs *nilfs, struct super_block *sb,
NILFS_CURRENT_REV, NILFS_MINOR_REV);
return -EINVAL;
}
+ nilfs->ns_sbsize = le16_to_cpu(sbp->s_bytes);
+ if (nilfs->ns_sbsize > BLOCK_SIZE)
+ return -EINVAL;
+
nilfs->ns_inode_size = le16_to_cpu(sbp->s_inode_size);
nilfs->ns_first_ino = le32_to_cpu(sbp->s_first_ino);
@@ -330,6 +333,122 @@ nilfs_store_disk_layout(struct the_nilfs *nilfs, struct super_block *sb,
return 0;
}
+static int nilfs_valid_sb(struct nilfs_super_block *sbp)
+{
+ static unsigned char sum[4];
+ const int sumoff = offsetof(struct nilfs_super_block, s_sum);
+ size_t bytes;
+ u32 crc;
+
+ if (!sbp || le16_to_cpu(sbp->s_magic) != NILFS_SUPER_MAGIC)
+ return 0;
+ bytes = le16_to_cpu(sbp->s_bytes);
+ if (bytes > BLOCK_SIZE)
+ return 0;
+ crc = crc32_le(le32_to_cpu(sbp->s_crc_seed), (unsigned char *)sbp,
+ sumoff);
+ crc = crc32_le(crc, sum, 4);
+ crc = crc32_le(crc, (unsigned char *)sbp + sumoff + 4,
+ bytes - sumoff - 4);
+ return crc == le32_to_cpu(sbp->s_sum);
+}
+
+static int nilfs_sb2_bad_offset(struct nilfs_super_block *sbp, u64 offset)
+{
+ return offset < ((le64_to_cpu(sbp->s_nsegments) *
+ le32_to_cpu(sbp->s_blocks_per_segment)) <<
+ (le32_to_cpu(sbp->s_log_block_size) + 10));
+}
+
+static void nilfs_release_super_block(struct the_nilfs *nilfs)
+{
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ if (nilfs->ns_sbp[i]) {
+ brelse(nilfs->ns_sbh[i]);
+ nilfs->ns_sbh[i] = NULL;
+ nilfs->ns_sbp[i] = NULL;
+ }
+ }
+}
+
+void nilfs_fall_back_super_block(struct the_nilfs *nilfs)
+{
+ brelse(nilfs->ns_sbh[0]);
+ nilfs->ns_sbh[0] = nilfs->ns_sbh[1];
+ nilfs->ns_sbp[0] = nilfs->ns_sbp[1];
+ nilfs->ns_sbh[1] = NULL;
+ nilfs->ns_sbp[1] = NULL;
+}
+
+void nilfs_swap_super_block(struct the_nilfs *nilfs)
+{
+ struct buffer_head *tsbh = nilfs->ns_sbh[0];
+ struct nilfs_super_block *tsbp = nilfs->ns_sbp[0];
+
+ nilfs->ns_sbh[0] = nilfs->ns_sbh[1];
+ nilfs->ns_sbp[0] = nilfs->ns_sbp[1];
+ nilfs->ns_sbh[1] = tsbh;
+ nilfs->ns_sbp[1] = tsbp;
+}
+
+static int nilfs_load_super_block(struct the_nilfs *nilfs,
+ struct super_block *sb, int blocksize,
+ struct nilfs_super_block **sbpp)
+{
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
+ struct buffer_head **sbh = nilfs->ns_sbh;
+ u64 sb2off = NILFS_SB2_OFFSET_BYTES(nilfs->ns_bdev->bd_inode->i_size);
+ int valid[2], swp = 0;
+
+ sbp[0] = nilfs_read_super_block(sb, NILFS_SB_OFFSET_BYTES, blocksize,
+ &sbh[0]);
+ sbp[1] = nilfs_read_super_block(sb, sb2off, blocksize, &sbh[1]);
+
+ if (!sbp[0]) {
+ if (!sbp[1]) {
+ printk(KERN_ERR "NILFS: unable to read superblock\n");
+ return -EIO;
+ }
+ printk(KERN_WARNING
+ "NILFS warning: unable to read primary superblock\n");
+ } else if (!sbp[1])
+ printk(KERN_WARNING
+ "NILFS warning: unable to read secondary superblock\n");
+
+ valid[0] = nilfs_valid_sb(sbp[0]);
+ valid[1] = nilfs_valid_sb(sbp[1]);
+ swp = valid[1] &&
+ (!valid[0] ||
+ le64_to_cpu(sbp[1]->s_wtime) > le64_to_cpu(sbp[0]->s_wtime));
+
+ if (valid[swp] && nilfs_sb2_bad_offset(sbp[swp], sb2off)) {
+ brelse(sbh[1]);
+ sbh[1] = NULL;
+ sbp[1] = NULL;
+ swp = 0;
+ }
+ if (!valid[swp]) {
+ nilfs_release_super_block(nilfs);
+ printk(KERN_ERR "NILFS: Can't find nilfs on dev %s.\n",
+ sb->s_id);
+ return -EINVAL;
+ }
+
+ if (swp) {
+ printk(KERN_WARNING "NILFS warning: broken superblock. "
+ "using spare superblock.\n");
+ nilfs_swap_super_block(nilfs);
+ }
+
+ nilfs->ns_sbwtime[0] = le64_to_cpu(sbp[0]->s_wtime);
+ nilfs->ns_sbwtime[1] = valid[!swp] ? le64_to_cpu(sbp[1]->s_wtime) : 0;
+ nilfs->ns_prot_seq = le64_to_cpu(sbp[valid[1] & !swp]->s_last_seq);
+ *sbpp = sbp[0];
+ return 0;
+}
+
/**
* init_nilfs - initialize a NILFS instance.
* @nilfs: the_nilfs structure
@@ -352,16 +471,15 @@ nilfs_store_disk_layout(struct the_nilfs *nilfs, struct super_block *sb,
int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data)
{
struct super_block *sb = sbi->s_super;
- struct buffer_head *sbh;
struct nilfs_super_block *sbp;
struct backing_dev_info *bdi;
int blocksize;
- int err = 0;
+ int err;
down_write(&nilfs->ns_sem);
if (nilfs_init(nilfs)) {
/* Load values from existing the_nilfs */
- sbp = nilfs->ns_sbp;
+ sbp = nilfs->ns_sbp[0];
err = nilfs_store_magic_and_option(sb, sbp, data);
if (err)
goto out;
@@ -377,36 +495,50 @@ int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data)
goto out;
}
- sbp = nilfs_load_super_block(sb, &sbh);
- if (!sbp) {
+ blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
+ if (!blocksize) {
+ printk(KERN_ERR "NILFS: unable to set blocksize\n");
err = -EINVAL;
goto out;
}
+ err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp);
+ if (err)
+ goto out;
+
err = nilfs_store_magic_and_option(sb, sbp, data);
if (err)
goto failed_sbh;
blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size);
if (sb->s_blocksize != blocksize) {
- sbp = nilfs_reload_super_block(sb, &sbh, blocksize);
- if (!sbp) {
+ int hw_blocksize = bdev_hardsect_size(sb->s_bdev);
+
+ if (blocksize < hw_blocksize) {
+ printk(KERN_ERR
+ "NILFS: blocksize %d too small for device "
+ "(sector-size = %d).\n",
+ blocksize, hw_blocksize);
err = -EINVAL;
+ goto failed_sbh;
+ }
+ nilfs_release_super_block(nilfs);
+ sb_set_blocksize(sb, blocksize);
+
+ err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp);
+ if (err)
goto out;
/* not failed_sbh; sbh is released automatically
when reloading fails. */
- }
}
nilfs->ns_blocksize_bits = sb->s_blocksize_bits;
- err = nilfs_store_disk_layout(nilfs, sb, sbp);
+ err = nilfs_store_disk_layout(nilfs, sbp);
if (err)
goto failed_sbh;
sb->s_maxbytes = nilfs_max_size(sb->s_blocksize_bits);
nilfs->ns_mount_state = le16_to_cpu(sbp->s_state);
- nilfs->ns_sbh = sbh;
- nilfs->ns_sbp = sbp;
bdi = nilfs->ns_bdev->bd_inode_backing_dev_info;
if (!bdi)
@@ -443,7 +575,7 @@ int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data)
return err;
failed_sbh:
- brelse(sbh);
+ nilfs_release_super_block(nilfs);
goto out;
}
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index d750e48257c94ba9c1be0a64284f138cd67ec98d..30fe58778d05a6a8ca335a0848e3a8467827d0ff 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -49,8 +49,10 @@ enum {
* @ns_sem: semaphore for shared states
* @ns_writer_mutex: mutex protecting ns_writer attach/detach
* @ns_writer_refcount: number of referrers on ns_writer
- * @ns_sbh: buffer head of the on-disk super block
- * @ns_sbp: pointer to the super block data
+ * @ns_sbh: buffer heads of on-disk super blocks
+ * @ns_sbp: pointers to super block data
+ * @ns_sbwtime: previous write time of super blocks
+ * @ns_sbsize: size of valid data in super block
* @ns_supers: list of nilfs super block structs
* @ns_seg_seq: segment sequence counter
* @ns_segnum: index number of the latest full segment.
@@ -101,8 +103,10 @@ struct the_nilfs {
* - protecting s_dirt in the super_block struct
* (see nilfs_write_super) and the following fields.
*/
- struct buffer_head *ns_sbh;
- struct nilfs_super_block *ns_sbp;
+ struct buffer_head *ns_sbh[2];
+ struct nilfs_super_block *ns_sbp[2];
+ time_t ns_sbwtime[2];
+ unsigned ns_sbsize;
unsigned ns_mount_state;
struct list_head ns_supers;
@@ -182,6 +186,10 @@ THE_NILFS_FNS(INIT, init)
THE_NILFS_FNS(LOADED, loaded)
THE_NILFS_FNS(DISCONTINUED, discontinued)
+/* Minimum interval of periodical update of superblocks (in seconds) */
+#define NILFS_SB_FREQ 10
+#define NILFS_ALTSB_FREQ 60 /* spare superblock */
+
void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
struct the_nilfs *alloc_nilfs(struct block_device *);
void put_nilfs(struct the_nilfs *);
@@ -190,6 +198,8 @@ int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *);
int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int);
int nilfs_near_disk_full(struct the_nilfs *);
+void nilfs_fall_back_super_block(struct the_nilfs *);
+void nilfs_swap_super_block(struct the_nilfs *);
static inline void get_nilfs(struct the_nilfs *nilfs)
diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h
index cbce6647f7fd0f2b4cde0e3ee2fa32aa58d51683..1275b3099535896c1ee3cba6e92726fe440a7a8e 100644
--- a/include/linux/nilfs2_fs.h
+++ b/include/linux/nilfs2_fs.h
@@ -252,6 +252,10 @@ struct nilfs_super_block {
#define NILFS_MIN_NRSVSEGS 8 /* Minimum number of reserved
segments */
+/*
+ * bytes offset of secondary super block
+ */
+#define NILFS_SB2_OFFSET_BYTES(devsize) ((((devsize) >> 12) - 1) << 12)
/*
* Maximal count of links to a file