* gcinodes), and this file provides lookup function of the dummy
* inodes and their buffer read function.
*
- * Since NILFS2 keeps up multiple checkpoints/snapshots across GC, it
- * has to treat blocks that belong to a same file but have different
- * checkpoint numbers. To avoid interference among generations, dummy
- * inodes are managed separately from actual inodes, and their lookup
- * function (nilfs_gc_iget) is designed to be specified with a
- * checkpoint number argument as well as an inode number.
- *
* Buffers and pages held by the dummy inodes will be released each
* time after they are copied to a new log. Dirty blocks made on the
* current generation and the blocks to be moved by GC never overlap
return 0;
}
-/*
- * nilfs_init_gccache() - allocate and initialize gc_inode hash table
- * @nilfs - the_nilfs
- *
- * Return Value: On success, 0.
- * On error, a negative error code is returned.
- */
-int nilfs_init_gccache(struct the_nilfs *nilfs)
-{
- int loop;
-
- BUG_ON(nilfs->ns_gc_inodes_h);
-
- INIT_LIST_HEAD(&nilfs->ns_gc_inodes);
-
- nilfs->ns_gc_inodes_h =
- kmalloc(sizeof(struct hlist_head) * NILFS_GCINODE_HASH_SIZE,
- GFP_NOFS);
- if (nilfs->ns_gc_inodes_h == NULL)
- return -ENOMEM;
-
- for (loop = 0; loop < NILFS_GCINODE_HASH_SIZE; loop++)
- INIT_HLIST_HEAD(&nilfs->ns_gc_inodes_h[loop]);
- return 0;
-}
-
-/*
- * nilfs_destroy_gccache() - free gc_inode hash table
- * @nilfs - the nilfs
- */
-void nilfs_destroy_gccache(struct the_nilfs *nilfs)
+int nilfs_init_gcinode(struct inode *inode)
{
- if (nilfs->ns_gc_inodes_h) {
- nilfs_remove_all_gcinode(nilfs);
- kfree(nilfs->ns_gc_inodes_h);
- nilfs->ns_gc_inodes_h = NULL;
- }
-}
-
-static struct inode *alloc_gcinode(struct the_nilfs *nilfs, ino_t ino,
- __u64 cno)
-{
- struct inode *inode;
- struct nilfs_inode_info *ii;
-
- inode = nilfs_mdt_new_common(nilfs, NULL, ino);
- if (!inode)
- return NULL;
-
- if (nilfs_mdt_init(inode, nilfs, GFP_NOFS, 0) < 0) {
- nilfs_destroy_inode(inode);
- return NULL;
- }
- inode->i_op = NULL;
- inode->i_fop = NULL;
- inode->i_mapping->a_ops = &def_gcinode_aops;
-
- ii = NILFS_I(inode);
- ii->i_cno = cno;
- ii->i_flags = 0;
- ii->i_state = 1 << NILFS_I_GCINODE;
- ii->i_bh = NULL;
- nilfs_bmap_init_gc(ii->i_bmap);
+ struct nilfs_inode_info *ii = NILFS_I(inode);
+ struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
+ int ret;
- return inode;
-}
+ ret = nilfs_mdt_init(inode, nilfs, GFP_NOFS, 0);
+ if (!ret) {
+ inode->i_mapping->a_ops = &def_gcinode_aops;
-static unsigned long ihash(ino_t ino, __u64 cno)
-{
- return hash_long((unsigned long)((ino << 2) + cno),
- NILFS_GCINODE_HASH_BITS);
-}
+ ii->i_flags = 0;
+ nilfs_bmap_init_gc(ii->i_bmap);
-/*
- * nilfs_gc_iget() - find or create gc inode with specified (ino,cno)
- */
-struct inode *nilfs_gc_iget(struct the_nilfs *nilfs, ino_t ino, __u64 cno)
-{
- struct hlist_head *head = nilfs->ns_gc_inodes_h + ihash(ino, cno);
- struct hlist_node *node;
- struct inode *inode;
-
- hlist_for_each_entry(inode, node, head, i_hash) {
- if (inode->i_ino == ino && NILFS_I(inode)->i_cno == cno)
- return inode;
- }
-
- inode = alloc_gcinode(nilfs, ino, cno);
- if (likely(inode)) {
- hlist_add_head(&inode->i_hash, head);
+ /*
+ * Add the inode to GC inode list. Garbage Collection
+ * is serialized and no two processes manipulate the
+ * list simultaneously.
+ */
+ igrab(inode);
list_add(&NILFS_I(inode)->i_dirty, &nilfs->ns_gc_inodes);
}
- return inode;
-}
-
-/*
- * nilfs_clear_gcinode() - clear and free a gc inode
- */
-void nilfs_clear_gcinode(struct inode *inode)
-{
- nilfs_mdt_destroy(inode);
+ return ret;
}
-/*
- * nilfs_remove_all_gcinode() - remove all inodes from the_nilfs
+/**
+ * nilfs_remove_all_gcinodes() - remove all unprocessed gc inodes
*/
-void nilfs_remove_all_gcinode(struct the_nilfs *nilfs)
+void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs)
{
- struct hlist_head *head = nilfs->ns_gc_inodes_h;
- struct hlist_node *node, *n;
- struct inode *inode;
- int loop;
+ struct list_head *head = &nilfs->ns_gc_inodes;
+ struct nilfs_inode_info *ii;
- for (loop = 0; loop < NILFS_GCINODE_HASH_SIZE; loop++, head++) {
- hlist_for_each_entry_safe(inode, node, n, head, i_hash) {
- hlist_del_init(&inode->i_hash);
- list_del_init(&NILFS_I(inode)->i_dirty);
- nilfs_clear_gcinode(inode); /* might sleep */
- }
+ while (!list_empty(head)) {
+ ii = list_first_entry(head, struct nilfs_inode_info, i_dirty);
+ list_del_init(&ii->i_dirty);
+ iput(&ii->vfs_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, .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)
{
return 0;
}
-static int nilfs_ioctl_move_blocks(struct the_nilfs *nilfs,
+static int nilfs_ioctl_move_blocks(struct super_block *sb,
struct nilfs_argv *argv, void *buf)
{
size_t nmembs = argv->v_nmembs;
for (i = 0, vdesc = buf; i < nmembs; ) {
ino = vdesc->vd_ino;
cno = vdesc->vd_cno;
- inode = nilfs_gc_iget(nilfs, ino, cno);
+ inode = nilfs_iget_for_gc(sb, ino, cno);
if (unlikely(inode == NULL)) {
ret = -ENOMEM;
goto failed;
do {
ret = nilfs_ioctl_move_inode_block(inode, vdesc,
&buffers);
- if (unlikely(ret < 0))
+ if (unlikely(ret < 0)) {
+ iput(inode);
goto failed;
+ }
vdesc++;
} while (++i < nmembs &&
vdesc->vd_ino == ino && vdesc->vd_cno == cno);
+
+ iput(inode); /* The inode still remains in GC inode list */
}
list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
}
/*
- * nilfs_ioctl_move_blocks() will call nilfs_gc_iget(),
+ * nilfs_ioctl_move_blocks() will call nilfs_iget_for_gc(),
* which will operates an inode list without blocking.
* To protect the list from concurrent operations,
* nilfs_ioctl_move_blocks should be atomic operation.
goto out_free;
}
- ret = nilfs_ioctl_move_blocks(nilfs, &argv[0], kbufs[0]);
+ ret = nilfs_ioctl_move_blocks(inode->i_sb, &argv[0], kbufs[0]);
if (ret < 0)
printk(KERN_ERR "NILFS: GC failed during preparation: "
"cannot read source blocks: err=%d\n", ret);
else
ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);
- if (ret < 0)
- nilfs_remove_all_gcinode(nilfs);
+ nilfs_remove_all_gcinodes(nilfs);
clear_nilfs_gc_running(nilfs);
out_free:
extern int nilfs_read_inode_common(struct inode *, struct nilfs_inode *);
extern void nilfs_write_inode_common(struct inode *, struct nilfs_inode *, int);
extern struct inode *nilfs_iget(struct super_block *, unsigned long);
+extern struct inode *nilfs_iget_for_gc(struct super_block *sb,
+ unsigned long ino, __u64 cno);
extern void nilfs_update_inode(struct inode *, struct buffer_head *);
extern void nilfs_truncate(struct inode *);
extern void nilfs_evict_inode(struct inode *);
int nilfs_gccache_submit_read_node(struct inode *, sector_t, __u64,
struct buffer_head **);
int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *);
-int nilfs_init_gccache(struct the_nilfs *);
-void nilfs_destroy_gccache(struct the_nilfs *);
-void nilfs_clear_gcinode(struct inode *);
-struct inode *nilfs_gc_iget(struct the_nilfs *, ino_t, __u64);
-void nilfs_remove_all_gcinode(struct the_nilfs *);
+int nilfs_init_gcinode(struct inode *inode);
+void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs);
/* gcdat.c */
int nilfs_init_gcdat_inode(struct the_nilfs *);
list_for_each_entry_safe(ii, n, head, i_dirty) {
if (!test_bit(NILFS_I_UPDATED, &ii->i_state))
continue;
- hlist_del_init(&ii->vfs_inode.i_hash);
list_del_init(&ii->i_dirty);
- nilfs_clear_gcinode(&ii->vfs_inode);
+ iput(&ii->vfs_inode);
}
}
init_rwsem(&nilfs->ns_writer_sem);
INIT_LIST_HEAD(&nilfs->ns_list);
INIT_LIST_HEAD(&nilfs->ns_supers);
+ INIT_LIST_HEAD(&nilfs->ns_gc_inodes);
spin_lock_init(&nilfs->ns_last_segment_lock);
- nilfs->ns_gc_inodes_h = NULL;
init_rwsem(&nilfs->ns_segctor_sem);
return nilfs;
nilfs_mdt_destroy(nilfs->ns_gc_dat);
}
if (nilfs_init(nilfs)) {
- nilfs_destroy_gccache(nilfs);
brelse(nilfs->ns_sbh[0]);
brelse(nilfs->ns_sbh[1]);
}
if (err)
goto failed_sbh;
- /* Initialize gcinode cache */
- err = nilfs_init_gccache(nilfs);
- if (err)
- goto failed_sbh;
-
set_nilfs_init(nilfs);
err = 0;
out:
* @ns_sufile: segusage file inode
* @ns_gc_dat: shadow inode of the DAT file inode for GC
* @ns_gc_inodes: dummy inodes to keep live blocks
- * @ns_gc_inodes_h: hash list to keep dummy inode holding live blocks
* @ns_blocksize_bits: bit length of block size
* @ns_blocksize: block size
* @ns_nsegments: number of segments in filesystem
struct inode *ns_sufile;
struct inode *ns_gc_dat;
- /* GC inode list and hash table head */
+ /* GC inode list */
struct list_head ns_gc_inodes;
- struct hlist_head *ns_gc_inodes_h;
/* Disk layout information (static) */
unsigned int ns_blocksize_bits;
u32 ns_crc_seed;
};
-#define NILFS_GCINODE_HASH_BITS 8
-#define NILFS_GCINODE_HASH_SIZE (1<<NILFS_GCINODE_HASH_BITS)
-
#define THE_NILFS_FNS(bit, name) \
static inline void set_nilfs_##name(struct the_nilfs *nilfs) \
{ \