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author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-08-27 00:23:02 +0900 |
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committer | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-10-23 09:24:34 +0900 |
commit | 8e656fd518784b49453f60c5f78b78703bc85cb2 (patch) | |
tree | 7adf4b71aba4bdf31dc05489a06933c48a0ea6f2 | |
parent | 4d8d9293dce503eb0e083e17a02a328d397e7f00 (diff) | |
download | linux-8e656fd518784b49453f60c5f78b78703bc85cb2.tar.bz2 |
nilfs2: make snapshots in checkpoint tree exportable
The previous export operations cannot handle multiple versions of
a filesystem if they belong to the same sb instance.
This adds a new type of file handle and extends export operations so
that they can get the inode specified by a checkpoint number as well
as an inode number and a generation number.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
-rw-r--r-- | fs/nilfs2/export.h | 17 | ||||
-rw-r--r-- | fs/nilfs2/namei.c | 137 | ||||
-rw-r--r-- | fs/nilfs2/nilfs.h | 3 | ||||
-rw-r--r-- | fs/nilfs2/super.c | 52 | ||||
-rw-r--r-- | include/linux/exportfs.h | 13 |
5 files changed, 151 insertions, 71 deletions
diff --git a/fs/nilfs2/export.h b/fs/nilfs2/export.h new file mode 100644 index 000000000000..a71cc412b651 --- /dev/null +++ b/fs/nilfs2/export.h @@ -0,0 +1,17 @@ +#ifndef NILFS_EXPORT_H +#define NILFS_EXPORT_H + +#include <linux/exportfs.h> + +extern const struct export_operations nilfs_export_ops; + +struct nilfs_fid { + u64 cno; + u64 ino; + u32 gen; + + u32 parent_gen; + u64 parent_ino; +} __attribute__ ((packed)); + +#endif diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c index 1110d56a23f5..a65f46560fbe 100644 --- a/fs/nilfs2/namei.c +++ b/fs/nilfs2/namei.c @@ -40,7 +40,11 @@ #include <linux/pagemap.h> #include "nilfs.h" +#include "export.h" +#define NILFS_FID_SIZE_NON_CONNECTABLE \ + (offsetof(struct nilfs_fid, parent_gen) / 4) +#define NILFS_FID_SIZE_CONNECTABLE (sizeof(struct nilfs_fid) / 4) static inline int nilfs_add_nondir(struct dentry *dentry, struct inode *inode) { @@ -77,23 +81,6 @@ nilfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) return d_splice_alias(inode, dentry); } -struct dentry *nilfs_get_parent(struct dentry *child) -{ - unsigned long ino; - struct inode *inode; - struct qstr dotdot = {.name = "..", .len = 2}; - - ino = nilfs_inode_by_name(child->d_inode, &dotdot); - if (!ino) - return ERR_PTR(-ENOENT); - - inode = nilfs_iget(child->d_inode->i_sb, - NILFS_I(child->d_inode)->i_root, ino); - if (IS_ERR(inode)) - return ERR_CAST(inode); - return d_obtain_alias(inode); -} - /* * By the time this is called, we already have created * the directory cache entry for the new file, but it @@ -469,6 +456,115 @@ out: return err; } +/* + * Export operations + */ +static struct dentry *nilfs_get_parent(struct dentry *child) +{ + unsigned long ino; + struct inode *inode; + struct qstr dotdot = {.name = "..", .len = 2}; + struct nilfs_root *root; + + ino = nilfs_inode_by_name(child->d_inode, &dotdot); + if (!ino) + return ERR_PTR(-ENOENT); + + root = NILFS_I(child->d_inode)->i_root; + + inode = nilfs_iget(child->d_inode->i_sb, root, ino); + if (IS_ERR(inode)) + return ERR_CAST(inode); + + return d_obtain_alias(inode); +} + +static struct dentry *nilfs_get_dentry(struct super_block *sb, u64 cno, + u64 ino, u32 gen) +{ + struct nilfs_root *root; + struct inode *inode; + + if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO) + return ERR_PTR(-ESTALE); + + root = nilfs_lookup_root(NILFS_SB(sb)->s_nilfs, cno); + if (!root) + return ERR_PTR(-ESTALE); + + inode = nilfs_iget(sb, root, ino); + nilfs_put_root(root); + + if (IS_ERR(inode)) + return ERR_CAST(inode); + if (gen && inode->i_generation != gen) { + iput(inode); + return ERR_PTR(-ESTALE); + } + return d_obtain_alias(inode); +} + +static struct dentry *nilfs_fh_to_dentry(struct super_block *sb, struct fid *fh, + int fh_len, int fh_type) +{ + struct nilfs_fid *fid = (struct nilfs_fid *)fh; + + if ((fh_len != NILFS_FID_SIZE_NON_CONNECTABLE && + fh_len != NILFS_FID_SIZE_CONNECTABLE) || + (fh_type != FILEID_NILFS_WITH_PARENT && + fh_type != FILEID_NILFS_WITHOUT_PARENT)) + return NULL; + + return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen); +} + +static struct dentry *nilfs_fh_to_parent(struct super_block *sb, struct fid *fh, + int fh_len, int fh_type) +{ + struct nilfs_fid *fid = (struct nilfs_fid *)fh; + + if (fh_len != NILFS_FID_SIZE_CONNECTABLE || + fh_type != FILEID_NILFS_WITH_PARENT) + return NULL; + + return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen); +} + +static int nilfs_encode_fh(struct dentry *dentry, __u32 *fh, int *lenp, + int connectable) +{ + struct nilfs_fid *fid = (struct nilfs_fid *)fh; + struct inode *inode = dentry->d_inode; + struct nilfs_root *root = NILFS_I(inode)->i_root; + int type; + + if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE || + (connectable && *lenp < NILFS_FID_SIZE_CONNECTABLE)) + return 255; + + fid->cno = root->cno; + fid->ino = inode->i_ino; + fid->gen = inode->i_generation; + + if (connectable && !S_ISDIR(inode->i_mode)) { + struct inode *parent; + + spin_lock(&dentry->d_lock); + parent = dentry->d_parent->d_inode; + fid->parent_ino = parent->i_ino; + fid->parent_gen = parent->i_generation; + spin_unlock(&dentry->d_lock); + + type = FILEID_NILFS_WITH_PARENT; + *lenp = NILFS_FID_SIZE_CONNECTABLE; + } else { + type = FILEID_NILFS_WITHOUT_PARENT; + *lenp = NILFS_FID_SIZE_NON_CONNECTABLE; + } + + return type; +} + const struct inode_operations nilfs_dir_inode_operations = { .create = nilfs_create, .lookup = nilfs_lookup, @@ -493,3 +589,10 @@ const struct inode_operations nilfs_symlink_inode_operations = { .follow_link = page_follow_link_light, .put_link = page_put_link, }; + +const struct export_operations nilfs_export_ops = { + .encode_fh = nilfs_encode_fh, + .fh_to_dentry = nilfs_fh_to_dentry, + .fh_to_parent = nilfs_fh_to_parent, + .get_parent = nilfs_get_parent, +}; diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h index 21d90c4b4e2d..aa7940f7ecf1 100644 --- a/fs/nilfs2/nilfs.h +++ b/fs/nilfs2/nilfs.h @@ -264,9 +264,6 @@ extern int nilfs_set_file_dirty(struct nilfs_sb_info *, struct inode *, extern int nilfs_mark_inode_dirty(struct inode *); extern void nilfs_dirty_inode(struct inode *); -/* namei.c */ -extern struct dentry *nilfs_get_parent(struct dentry *); - /* super.c */ extern struct inode *nilfs_alloc_inode_common(struct the_nilfs *); extern struct inode *nilfs_alloc_inode(struct super_block *); diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index a1c0e38a7706..adbf5826b837 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" @@ -556,56 +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; - struct nilfs_root *root; - - if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO && - ino != NILFS_SKETCH_INO) - return ERR_PTR(-ESTALE); - - root = nilfs_lookup_root(NILFS_SB(sb)->s_nilfs, - NILFS_CPTREE_CURRENT_CNO); - if (!root) - return ERR_PTR(-ESTALE); - - /* new file handle type is required to export snapshots */ - inode = nilfs_iget(sb, root, ino); - nilfs_put_root(root); - 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, diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index a9cd507f8cd2..28028988c862 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -67,6 +67,19 @@ enum fid_type { * 32 bit parent block number, 32 bit parent generation number */ FILEID_UDF_WITH_PARENT = 0x52, + + /* + * 64 bit checkpoint number, 64 bit inode number, + * 32 bit generation number. + */ + FILEID_NILFS_WITHOUT_PARENT = 0x61, + + /* + * 64 bit checkpoint number, 64 bit inode number, + * 32 bit generation number, 32 bit parent generation. + * 64 bit parent inode number. + */ + FILEID_NILFS_WITH_PARENT = 0x62, }; struct fid { |