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authorLinus Torvalds <torvalds@linux-foundation.org>2010-10-23 01:26:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-10-23 01:26:47 -0700
commitab34c02afeafd047a831e6fe2a4dd875ce86bee0 (patch)
tree833e385e8387e3d4d4531ade23c1d92fba8ed075 /fs/nilfs2/super.c
parent7f3883962870dd28b5f2322ac44a9d03640ef448 (diff)
parent6b81e14e645016597c81e71cd27ee5c57c3a3c36 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (36 commits) nilfs2: eliminate sparse warning - "context imbalance" nilfs2: eliminate sparse warnings - "symbol not declared" nilfs2: get rid of bdi from nilfs object nilfs2: change license of exported header file nilfs2: add bdev freeze/thaw support nilfs2: accept 64-bit checkpoint numbers in cp mount option nilfs2: remove own inode allocator and destructor for metadata files nilfs2: get rid of back pointer to writable sb instance nilfs2: get rid of mi_nilfs back pointer to nilfs object nilfs2: see state of root dentry for mount check of snapshots nilfs2: use iget for all metadata files nilfs2: get rid of GCDAT inode nilfs2: add routines to redirect access to buffers of DAT file nilfs2: add routines to roll back state of DAT file nilfs2: add routines to save and restore bmap state nilfs2: do not allocate nilfs_mdt_info structure to gc-inodes nilfs2: allow nilfs_clear_inode to clear metadata file inodes nilfs2: get rid of snapshot mount flag nilfs2: simplify life cycle management of nilfs object nilfs2: do not allocate multiple super block instances for a device ...
Diffstat (limited to 'fs/nilfs2/super.c')
-rw-r--r--fs/nilfs2/super.c609
1 files changed, 327 insertions, 282 deletions
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index f3b75206e956..35ae03c0db86 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -48,10 +48,10 @@
#include <linux/vfs.h>
#include <linux/writeback.h>
#include <linux/kobject.h>
-#include <linux/exportfs.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include "nilfs.h"
+#include "export.h"
#include "mdt.h"
#include "alloc.h"
#include "btree.h"
@@ -68,11 +68,12 @@ MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
"(NILFS)");
MODULE_LICENSE("GPL");
-struct kmem_cache *nilfs_inode_cachep;
+static struct kmem_cache *nilfs_inode_cachep;
struct kmem_cache *nilfs_transaction_cachep;
struct kmem_cache *nilfs_segbuf_cachep;
struct kmem_cache *nilfs_btree_path_cache;
+static int nilfs_setup_super(struct nilfs_sb_info *sbi, int is_mount);
static int nilfs_remount(struct super_block *sb, int *flags, char *data);
static void nilfs_set_error(struct nilfs_sb_info *sbi)
@@ -146,7 +147,7 @@ void nilfs_warning(struct super_block *sb, const char *function,
}
-struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
+struct inode *nilfs_alloc_inode(struct super_block *sb)
{
struct nilfs_inode_info *ii;
@@ -155,18 +156,20 @@ struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
return NULL;
ii->i_bh = NULL;
ii->i_state = 0;
+ ii->i_cno = 0;
ii->vfs_inode.i_version = 1;
- nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
+ nilfs_btnode_cache_init(&ii->i_btnode_cache, sb->s_bdi);
return &ii->vfs_inode;
}
-struct inode *nilfs_alloc_inode(struct super_block *sb)
-{
- return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
-}
-
void nilfs_destroy_inode(struct inode *inode)
{
+ struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
+
+ if (mdi) {
+ kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
+ kfree(mdi);
+ }
kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
}
@@ -340,16 +343,15 @@ static void nilfs_put_super(struct super_block *sb)
nilfs_cleanup_super(sbi);
up_write(&nilfs->ns_sem);
}
- down_write(&nilfs->ns_super_sem);
- if (nilfs->ns_current == sbi)
- nilfs->ns_current = NULL;
- up_write(&nilfs->ns_super_sem);
- nilfs_detach_checkpoint(sbi);
- put_nilfs(sbi->s_nilfs);
+ iput(nilfs->ns_sufile);
+ iput(nilfs->ns_cpfile);
+ iput(nilfs->ns_dat);
+
+ destroy_nilfs(nilfs);
sbi->s_super = NULL;
sb->s_fs_info = NULL;
- nilfs_put_sbinfo(sbi);
+ kfree(sbi);
}
static int nilfs_sync_fs(struct super_block *sb, int wait)
@@ -376,21 +378,22 @@ static int nilfs_sync_fs(struct super_block *sb, int wait)
return err;
}
-int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
+int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno, int curr_mnt,
+ struct nilfs_root **rootp)
{
struct the_nilfs *nilfs = sbi->s_nilfs;
+ struct nilfs_root *root;
struct nilfs_checkpoint *raw_cp;
struct buffer_head *bh_cp;
- int err;
+ int err = -ENOMEM;
- down_write(&nilfs->ns_super_sem);
- list_add(&sbi->s_list, &nilfs->ns_supers);
- up_write(&nilfs->ns_super_sem);
+ root = nilfs_find_or_create_root(
+ nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
+ if (!root)
+ return err;
- err = -ENOMEM;
- sbi->s_ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
- if (!sbi->s_ifile)
- goto delist;
+ if (root->ifile)
+ goto reuse; /* already attached checkpoint */
down_read(&nilfs->ns_segctor_sem);
err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
@@ -406,45 +409,64 @@ int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
}
goto failed;
}
- err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
- if (unlikely(err))
+
+ err = nilfs_ifile_read(sbi->s_super, root, nilfs->ns_inode_size,
+ &raw_cp->cp_ifile_inode, &root->ifile);
+ if (err)
goto failed_bh;
- atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
- atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
+
+ atomic_set(&root->inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
+ atomic_set(&root->blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
+
+ reuse:
+ *rootp = root;
return 0;
failed_bh:
nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
failed:
- nilfs_mdt_destroy(sbi->s_ifile);
- sbi->s_ifile = NULL;
+ nilfs_put_root(root);
+
+ return err;
+}
- delist:
- down_write(&nilfs->ns_super_sem);
- list_del_init(&sbi->s_list);
- up_write(&nilfs->ns_super_sem);
+static int nilfs_freeze(struct super_block *sb)
+{
+ struct nilfs_sb_info *sbi = NILFS_SB(sb);
+ struct the_nilfs *nilfs = sbi->s_nilfs;
+ int err;
+
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+ /* Mark super block clean */
+ down_write(&nilfs->ns_sem);
+ err = nilfs_cleanup_super(sbi);
+ up_write(&nilfs->ns_sem);
return err;
}
-void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
+static int nilfs_unfreeze(struct super_block *sb)
{
+ struct nilfs_sb_info *sbi = NILFS_SB(sb);
struct the_nilfs *nilfs = sbi->s_nilfs;
- nilfs_mdt_destroy(sbi->s_ifile);
- sbi->s_ifile = NULL;
- down_write(&nilfs->ns_super_sem);
- list_del_init(&sbi->s_list);
- up_write(&nilfs->ns_super_sem);
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+
+ down_write(&nilfs->ns_sem);
+ nilfs_setup_super(sbi, false);
+ up_write(&nilfs->ns_sem);
+ return 0;
}
static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
- struct nilfs_sb_info *sbi = NILFS_SB(sb);
- struct the_nilfs *nilfs = sbi->s_nilfs;
+ struct nilfs_root *root = NILFS_I(dentry->d_inode)->i_root;
+ struct the_nilfs *nilfs = root->nilfs;
u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
unsigned long long blocks;
unsigned long overhead;
@@ -480,7 +502,7 @@ static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_bfree = nfreeblocks;
buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
(buf->f_bfree - nrsvblocks) : 0;
- buf->f_files = atomic_read(&sbi->s_inodes_count);
+ buf->f_files = atomic_read(&root->inodes_count);
buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
buf->f_namelen = NILFS_NAME_LEN;
buf->f_fsid.val[0] = (u32)id;
@@ -493,12 +515,12 @@ static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
{
struct super_block *sb = vfs->mnt_sb;
struct nilfs_sb_info *sbi = NILFS_SB(sb);
+ struct nilfs_root *root = NILFS_I(vfs->mnt_root->d_inode)->i_root;
if (!nilfs_test_opt(sbi, BARRIER))
seq_puts(seq, ",nobarrier");
- if (nilfs_test_opt(sbi, SNAPSHOT))
- seq_printf(seq, ",cp=%llu",
- (unsigned long long int)sbi->s_snapshot_cno);
+ if (root->cno != NILFS_CPTREE_CURRENT_CNO)
+ seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno);
if (nilfs_test_opt(sbi, ERRORS_PANIC))
seq_puts(seq, ",errors=panic");
if (nilfs_test_opt(sbi, ERRORS_CONT))
@@ -524,6 +546,8 @@ static const struct super_operations nilfs_sops = {
.put_super = nilfs_put_super,
/* .write_super = nilfs_write_super, */
.sync_fs = nilfs_sync_fs,
+ .freeze_fs = nilfs_freeze,
+ .unfreeze_fs = nilfs_unfreeze,
/* .write_super_lockfs */
/* .unlockfs */
.statfs = nilfs_statfs,
@@ -532,48 +556,6 @@ static const struct super_operations nilfs_sops = {
.show_options = nilfs_show_options
};
-static struct inode *
-nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
-{
- struct inode *inode;
-
- if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
- ino != NILFS_SKETCH_INO)
- return ERR_PTR(-ESTALE);
-
- inode = nilfs_iget(sb, ino);
- if (IS_ERR(inode))
- return ERR_CAST(inode);
- if (generation && inode->i_generation != generation) {
- iput(inode);
- return ERR_PTR(-ESTALE);
- }
-
- return inode;
-}
-
-static struct dentry *
-nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
- int fh_type)
-{
- return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
- nilfs_nfs_get_inode);
-}
-
-static struct dentry *
-nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
- int fh_type)
-{
- return generic_fh_to_parent(sb, fid, fh_len, fh_type,
- nilfs_nfs_get_inode);
-}
-
-static const struct export_operations nilfs_export_ops = {
- .fh_to_dentry = nilfs_fh_to_dentry,
- .fh_to_parent = nilfs_fh_to_parent,
- .get_parent = nilfs_get_parent,
-};
-
enum {
Opt_err_cont, Opt_err_panic, Opt_err_ro,
Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
@@ -599,7 +581,6 @@ static int parse_options(char *options, struct super_block *sb, int is_remount)
struct nilfs_sb_info *sbi = NILFS_SB(sb);
char *p;
substring_t args[MAX_OPT_ARGS];
- int option;
if (!options)
return 1;
@@ -637,30 +618,12 @@ static int parse_options(char *options, struct super_block *sb, int is_remount)
nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
break;
case Opt_snapshot:
- if (match_int(&args[0], &option) || option <= 0)
- return 0;
if (is_remount) {
- if (!nilfs_test_opt(sbi, SNAPSHOT)) {
- printk(KERN_ERR
- "NILFS: cannot change regular "
- "mount to snapshot.\n");
- return 0;
- } else if (option != sbi->s_snapshot_cno) {
- printk(KERN_ERR
- "NILFS: cannot remount to a "
- "different snapshot.\n");
- return 0;
- }
- break;
- }
- if (!(sb->s_flags & MS_RDONLY)) {
- printk(KERN_ERR "NILFS: cannot mount snapshot "
- "read/write. A read-only option is "
- "required.\n");
+ printk(KERN_ERR
+ "NILFS: \"%s\" option is invalid "
+ "for remount.\n", p);
return 0;
}
- sbi->s_snapshot_cno = option;
- nilfs_set_opt(sbi, SNAPSHOT);
break;
case Opt_norecovery:
nilfs_set_opt(sbi, NORECOVERY);
@@ -688,7 +651,7 @@ nilfs_set_default_options(struct nilfs_sb_info *sbi,
NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
}
-static int nilfs_setup_super(struct nilfs_sb_info *sbi)
+static int nilfs_setup_super(struct nilfs_sb_info *sbi, int is_mount)
{
struct the_nilfs *nilfs = sbi->s_nilfs;
struct nilfs_super_block **sbp;
@@ -700,6 +663,9 @@ static int nilfs_setup_super(struct nilfs_sb_info *sbi)
if (!sbp)
return -EIO;
+ if (!is_mount)
+ goto skip_mount_setup;
+
max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
@@ -716,9 +682,11 @@ static int nilfs_setup_super(struct nilfs_sb_info *sbi)
sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
+ sbp[0]->s_mtime = cpu_to_le64(get_seconds());
+
+skip_mount_setup:
sbp[0]->s_state =
cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
- sbp[0]->s_mtime = cpu_to_le64(get_seconds());
/* synchronize sbp[1] with sbp[0] */
memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
@@ -785,22 +753,156 @@ int nilfs_check_feature_compatibility(struct super_block *sb,
return 0;
}
+static int nilfs_get_root_dentry(struct super_block *sb,
+ struct nilfs_root *root,
+ struct dentry **root_dentry)
+{
+ struct inode *inode;
+ struct dentry *dentry;
+ int ret = 0;
+
+ inode = nilfs_iget(sb, root, NILFS_ROOT_INO);
+ if (IS_ERR(inode)) {
+ printk(KERN_ERR "NILFS: get root inode failed\n");
+ ret = PTR_ERR(inode);
+ goto out;
+ }
+ if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) {
+ iput(inode);
+ printk(KERN_ERR "NILFS: corrupt root inode.\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
+ dentry = d_find_alias(inode);
+ if (!dentry) {
+ dentry = d_alloc_root(inode);
+ if (!dentry) {
+ iput(inode);
+ ret = -ENOMEM;
+ goto failed_dentry;
+ }
+ } else {
+ iput(inode);
+ }
+ } else {
+ dentry = d_obtain_alias(inode);
+ if (IS_ERR(dentry)) {
+ ret = PTR_ERR(dentry);
+ goto failed_dentry;
+ }
+ }
+ *root_dentry = dentry;
+ out:
+ return ret;
+
+ failed_dentry:
+ printk(KERN_ERR "NILFS: get root dentry failed\n");
+ goto out;
+}
+
+static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
+ struct dentry **root_dentry)
+{
+ struct the_nilfs *nilfs = NILFS_SB(s)->s_nilfs;
+ struct nilfs_root *root;
+ int ret;
+
+ down_read(&nilfs->ns_segctor_sem);
+ ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
+ up_read(&nilfs->ns_segctor_sem);
+ if (ret < 0) {
+ ret = (ret == -ENOENT) ? -EINVAL : ret;
+ goto out;
+ } else if (!ret) {
+ printk(KERN_ERR "NILFS: The specified checkpoint is "
+ "not a snapshot (checkpoint number=%llu).\n",
+ (unsigned long long)cno);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = nilfs_attach_checkpoint(NILFS_SB(s), cno, false, &root);
+ if (ret) {
+ printk(KERN_ERR "NILFS: error loading snapshot "
+ "(checkpoint number=%llu).\n",
+ (unsigned long long)cno);
+ goto out;
+ }
+ ret = nilfs_get_root_dentry(s, root, root_dentry);
+ nilfs_put_root(root);
+ out:
+ return ret;
+}
+
+static int nilfs_tree_was_touched(struct dentry *root_dentry)
+{
+ return atomic_read(&root_dentry->d_count) > 1;
+}
+
+/**
+ * nilfs_try_to_shrink_tree() - try to shrink dentries of a checkpoint
+ * @root_dentry: root dentry of the tree to be shrunk
+ *
+ * This function returns true if the tree was in-use.
+ */
+static int nilfs_try_to_shrink_tree(struct dentry *root_dentry)
+{
+ if (have_submounts(root_dentry))
+ return true;
+ shrink_dcache_parent(root_dentry);
+ return nilfs_tree_was_touched(root_dentry);
+}
+
+int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno)
+{
+ struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
+ struct nilfs_root *root;
+ struct inode *inode;
+ struct dentry *dentry;
+ int ret;
+
+ if (cno < 0 || cno > nilfs->ns_cno)
+ return false;
+
+ if (cno >= nilfs_last_cno(nilfs))
+ return true; /* protect recent checkpoints */
+
+ ret = false;
+ root = nilfs_lookup_root(NILFS_SB(sb)->s_nilfs, cno);
+ if (root) {
+ inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO);
+ if (inode) {
+ dentry = d_find_alias(inode);
+ if (dentry) {
+ if (nilfs_tree_was_touched(dentry))
+ ret = nilfs_try_to_shrink_tree(dentry);
+ dput(dentry);
+ }
+ iput(inode);
+ }
+ nilfs_put_root(root);
+ }
+ return ret;
+}
+
/**
* nilfs_fill_super() - initialize a super block instance
* @sb: super_block
* @data: mount options
* @silent: silent mode flag
- * @nilfs: the_nilfs struct
*
* This function is called exclusively by nilfs->ns_mount_mutex.
* So, the recovery process is protected from other simultaneous mounts.
*/
static int
-nilfs_fill_super(struct super_block *sb, void *data, int silent,
- struct the_nilfs *nilfs)
+nilfs_fill_super(struct super_block *sb, void *data, int silent)
{
+ struct the_nilfs *nilfs;
struct nilfs_sb_info *sbi;
- struct inode *root;
+ struct nilfs_root *fsroot;
+ struct backing_dev_info *bdi;
__u64 cno;
int err;
@@ -809,19 +911,21 @@ nilfs_fill_super(struct super_block *sb, void *data, int silent,
return -ENOMEM;
sb->s_fs_info = sbi;
+ sbi->s_super = sb;
- get_nilfs(nilfs);
+ nilfs = alloc_nilfs(sb->s_bdev);
+ if (!nilfs) {
+ err = -ENOMEM;
+ goto failed_sbi;
+ }
sbi->s_nilfs = nilfs;
- sbi->s_super = sb;
- atomic_set(&sbi->s_count, 1);
err = init_nilfs(nilfs, sbi, (char *)data);
if (err)
- goto failed_sbi;
+ goto failed_nilfs;
spin_lock_init(&sbi->s_inode_lock);
INIT_LIST_HEAD(&sbi->s_dirty_files);
- INIT_LIST_HEAD(&sbi->s_list);
/*
* Following initialization is overlapped because
@@ -837,94 +941,59 @@ nilfs_fill_super(struct super_block *sb, void *data, int silent,
sb->s_export_op = &nilfs_export_ops;
sb->s_root = NULL;
sb->s_time_gran = 1;
- sb->s_bdi = nilfs->ns_bdi;
+
+ bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
+ sb->s_bdi = bdi ? : &default_backing_dev_info;
err = load_nilfs(nilfs, sbi);
if (err)
- goto failed_sbi;
+ goto failed_nilfs;
cno = nilfs_last_cno(nilfs);
-
- if (sb->s_flags & MS_RDONLY) {
- if (nilfs_test_opt(sbi, SNAPSHOT)) {
- down_read(&nilfs->ns_segctor_sem);
- err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
- sbi->s_snapshot_cno);
- up_read(&nilfs->ns_segctor_sem);
- if (err < 0) {
- if (err == -ENOENT)
- err = -EINVAL;
- goto failed_sbi;
- }
- if (!err) {
- printk(KERN_ERR
- "NILFS: The specified checkpoint is "
- "not a snapshot "
- "(checkpoint number=%llu).\n",
- (unsigned long long)sbi->s_snapshot_cno);
- err = -EINVAL;
- goto failed_sbi;
- }
- cno = sbi->s_snapshot_cno;
- }
- }
-
- err = nilfs_attach_checkpoint(sbi, cno);
+ err = nilfs_attach_checkpoint(sbi, cno, true, &fsroot);
if (err) {
- printk(KERN_ERR "NILFS: error loading a checkpoint"
- " (checkpoint number=%llu).\n", (unsigned long long)cno);
- goto failed_sbi;
+ printk(KERN_ERR "NILFS: error loading last checkpoint "
+ "(checkpoint number=%llu).\n", (unsigned long long)cno);
+ goto failed_unload;
}
if (!(sb->s_flags & MS_RDONLY)) {
- err = nilfs_attach_segment_constructor(sbi);
+ err = nilfs_attach_segment_constructor(sbi, fsroot);
if (err)
goto failed_checkpoint;
}
- root = nilfs_iget(sb, NILFS_ROOT_INO);
- if (IS_ERR(root)) {
- printk(KERN_ERR "NILFS: get root inode failed\n");
- err = PTR_ERR(root);
- goto failed_segctor;
- }
- if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
- iput(root);
- printk(KERN_ERR "NILFS: corrupt root inode.\n");
- err = -EINVAL;
- goto failed_segctor;
- }
- sb->s_root = d_alloc_root(root);
- if (!sb->s_root) {
- iput(root);
- printk(KERN_ERR "NILFS: get root dentry failed\n");
- err = -ENOMEM;
+ err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
+ if (err)
goto failed_segctor;
- }
+
+ nilfs_put_root(fsroot);
if (!(sb->s_flags & MS_RDONLY)) {
down_write(&nilfs->ns_sem);
- nilfs_setup_super(sbi);
+ nilfs_setup_super(sbi, true);
up_write(&nilfs->ns_sem);
}
- down_write(&nilfs->ns_super_sem);
- if (!nilfs_test_opt(sbi, SNAPSHOT))
- nilfs->ns_current = sbi;
- up_write(&nilfs->ns_super_sem);
-
return 0;
failed_segctor:
nilfs_detach_segment_constructor(sbi);
failed_checkpoint:
- nilfs_detach_checkpoint(sbi);
+ nilfs_put_root(fsroot);
+
+ failed_unload:
+ iput(nilfs->ns_sufile);
+ iput(nilfs->ns_cpfile);
+ iput(nilfs->ns_dat);
+
+ failed_nilfs:
+ destroy_nilfs(nilfs);
failed_sbi:
- put_nilfs(nilfs);
sb->s_fs_info = NULL;
- nilfs_put_sbinfo(sbi);
+ kfree(sbi);
return err;
}
@@ -934,13 +1003,10 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
struct the_nilfs *nilfs = sbi->s_nilfs;
unsigned long old_sb_flags;
struct nilfs_mount_options old_opts;
- int was_snapshot, err;
+ int err;
- down_write(&nilfs->ns_super_sem);
old_sb_flags = sb->s_flags;
old_opts.mount_opt = sbi->s_mount_opt;
- old_opts.snapshot_cno = sbi->s_snapshot_cno;
- was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
if (!parse_options(data, sb, 1)) {
err = -EINVAL;
@@ -949,11 +1015,6 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
err = -EINVAL;
- if (was_snapshot && !(*flags & MS_RDONLY)) {
- printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
- "read/write.\n", sb->s_id);
- goto restore_opts;
- }
if (!nilfs_valid_fs(nilfs)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
@@ -978,6 +1039,7 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
up_write(&nilfs->ns_sem);
} else {
__u64 features;
+ struct nilfs_root *root;
/*
* Mounting a RDONLY partition read-write, so reread and
@@ -999,23 +1061,21 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
sb->s_flags &= ~MS_RDONLY;
- err = nilfs_attach_segment_constructor(sbi);
+ root = NILFS_I(sb->s_root->d_inode)->i_root;
+ err = nilfs_attach_segment_constructor(sbi, root);
if (err)
goto restore_opts;
down_write(&nilfs->ns_sem);
- nilfs_setup_super(sbi);
+ nilfs_setup_super(sbi, true);
up_write(&nilfs->ns_sem);
}
out:
- up_write(&nilfs->ns_super_sem);
return 0;
restore_opts:
sb->s_flags = old_sb_flags;
sbi->s_mount_opt = old_opts.mount_opt;
- sbi->s_snapshot_cno = old_opts.snapshot_cno;
- up_write(&nilfs->ns_super_sem);
return err;
}
@@ -1035,7 +1095,7 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd)
{
char *p, *options = data;
substring_t args[MAX_OPT_ARGS];
- int option, token;
+ int token;
int ret = 0;
do {
@@ -1043,16 +1103,18 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd)
if (p != NULL && *p) {
token = match_token(p, tokens, args);
if (token == Opt_snapshot) {
- if (!(sd->flags & MS_RDONLY))
+ if (!(sd->flags & MS_RDONLY)) {
ret++;
- else {
- ret = match_int(&args[0], &option);
- if (!ret) {
- if (option > 0)
- sd->cno = option;
- else
- ret++;
- }
+ } else {
+ sd->cno = simple_strtoull(args[0].from,
+ NULL, 0);
+ /*
+ * No need to see the end pointer;
+ * match_token() has done syntax
+ * checking.
+ */
+ if (sd->cno == 0)
+ ret++;
}
}
if (ret)
@@ -1069,18 +1131,14 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd)
static int nilfs_set_bdev_super(struct super_block *s, void *data)
{
- struct nilfs_super_data *sd = data;
-
- s->s_bdev = sd->bdev;
+ s->s_bdev = data;
s->s_dev = s->s_bdev->bd_dev;
return 0;
}
static int nilfs_test_bdev_super(struct super_block *s, void *data)
{
- struct nilfs_super_data *sd = data;
-
- return sd->sbi && s->s_fs_info == (void *)sd->sbi;
+ return (void *)s->s_bdev == data;
}
static int
@@ -1090,8 +1148,8 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags,
struct nilfs_super_data sd;
struct super_block *s;
fmode_t mode = FMODE_READ;
- struct the_nilfs *nilfs;
- int err, need_to_close = 1;
+ struct dentry *root_dentry;
+ int err, s_new = false;
if (!(flags & MS_RDONLY))
mode |= FMODE_WRITE;
@@ -1100,12 +1158,6 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags,
if (IS_ERR(sd.bdev))
return PTR_ERR(sd.bdev);
- /*
- * To get mount instance using sget() vfs-routine, NILFS needs
- * much more information than normal filesystems to identify mount
- * instance. For snapshot mounts, not only a mount type (ro-mount
- * or rw-mount) but also a checkpoint number is required.
- */
sd.cno = 0;
sd.flags = flags;
if (nilfs_identify((char *)data, &sd)) {
@@ -1113,93 +1165,86 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags,
goto failed;
}
- nilfs = find_or_create_nilfs(sd.bdev);
- if (!nilfs) {
- err = -ENOMEM;
- goto failed;
- }
-
- mutex_lock(&nilfs->ns_mount_mutex);
-
- if (!sd.cno) {
- /*
- * Check if an exclusive mount exists or not.
- * Snapshot mounts coexist with a current mount
- * (i.e. rw-mount or ro-mount), whereas rw-mount and
- * ro-mount are mutually exclusive.
- */
- down_read(&nilfs->ns_super_sem);
- if (nilfs->ns_current &&
- ((nilfs->ns_current->s_super->s_flags ^ flags)
- & MS_RDONLY)) {
- up_read(&nilfs->ns_super_sem);
- err = -EBUSY;
- goto failed_unlock;
- }
- up_read(&nilfs->ns_super_sem);
- }
-
- /*
- * Find existing nilfs_sb_info struct
- */
- sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
-
/*
- * Get super block instance holding the nilfs_sb_info struct.
- * A new instance is allocated if no existing mount is present or
- * existing instance has been unmounted.
+ * once the super is inserted into the list by sget, s_umount
+ * will protect the lockfs code from trying to start a snapshot
+ * while we are mounting
*/
- s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
- if (sd.sbi)
- nilfs_put_sbinfo(sd.sbi);
-
+ mutex_lock(&sd.bdev->bd_fsfreeze_mutex);
+ if (sd.bdev->bd_fsfreeze_count > 0) {
+ mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
+ err = -EBUSY;
+ goto failed;
+ }
+ s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, sd.bdev);
+ mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
if (IS_ERR(s)) {
err = PTR_ERR(s);
- goto failed_unlock;
+ goto failed;
}
if (!s->s_root) {
char b[BDEVNAME_SIZE];
+ s_new = true;
+
/* New superblock instance created */
s->s_flags = flags;
s->s_mode = mode;
strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
sb_set_blocksize(s, block_size(sd.bdev));
- err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
- nilfs);
+ err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
if (err)
- goto cancel_new;
+ goto failed_super;
s->s_flags |= MS_ACTIVE;
- need_to_close = 0;
+ } else if (!sd.cno) {
+ int busy = false;
+
+ if (nilfs_tree_was_touched(s->s_root)) {
+ busy = nilfs_try_to_shrink_tree(s->s_root);
+ if (busy && (flags ^ s->s_flags) & MS_RDONLY) {
+ printk(KERN_ERR "NILFS: the device already "
+ "has a %s mount.\n",
+ (s->s_flags & MS_RDONLY) ?
+ "read-only" : "read/write");
+ err = -EBUSY;
+ goto failed_super;
+ }
+ }
+ if (!busy) {
+ /*
+ * Try remount to setup mount states if the current
+ * tree is not mounted and only snapshots use this sb.
+ */
+ err = nilfs_remount(s, &flags, data);
+ if (err)
+ goto failed_super;
+ }
}
- mutex_unlock(&nilfs->ns_mount_mutex);
- put_nilfs(nilfs);
- if (need_to_close)
+ if (sd.cno) {
+ err = nilfs_attach_snapshot(s, sd.cno, &root_dentry);
+ if (err)
+ goto failed_super;
+ } else {
+ root_dentry = dget(s->s_root);
+ }
+
+ if (!s_new)
close_bdev_exclusive(sd.bdev, mode);
- simple_set_mnt(mnt, s);
- return 0;
- failed_unlock:
- mutex_unlock(&nilfs->ns_mount_mutex);
- put_nilfs(nilfs);
- failed:
- close_bdev_exclusive(sd.bdev, mode);
- return err;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = root_dentry;
+ return 0;
- cancel_new:
- /* Abandoning the newly allocated superblock */
- mutex_unlock(&nilfs->ns_mount_mutex);
- put_nilfs(nilfs);
+ failed_super:
deactivate_locked_super(s);
- /*
- * deactivate_locked_super() invokes close_bdev_exclusive().
- * We must finish all post-cleaning before this call;
- * put_nilfs() needs the block device.
- */
+
+ failed:
+ if (!s_new)
+ close_bdev_exclusive(sd.bdev, mode);
return err;
}