#define NILFS_MDT_MAX_RA_BLOCKS (16 - 1)
-#define INIT_UNUSED_INODE_FIELDS
static int
nilfs_mdt_insert_new_block(struct inode *inode, unsigned long block,
struct buffer_head *,
void *))
{
- struct the_nilfs *nilfs = NILFS_MDT(inode)->mi_nilfs;
struct super_block *sb = inode->i_sb;
struct nilfs_transaction_info ti;
struct buffer_head *bh;
int err;
- if (!sb) {
- /*
- * Make sure this function is not called from any
- * read-only context.
- */
- if (!nilfs->ns_writer) {
- WARN_ON(1);
- err = -EROFS;
- goto out;
- }
- sb = nilfs->ns_writer->s_super;
- }
-
nilfs_transaction_begin(sb, &ti, 0);
err = -ENOMEM;
if (buffer_uptodate(bh))
goto failed_bh;
- bh->b_bdev = nilfs->ns_bdev;
+ bh->b_bdev = sb->s_bdev;
err = nilfs_mdt_insert_new_block(inode, block, bh, init_block);
if (likely(!err)) {
get_bh(bh);
err = nilfs_transaction_commit(sb);
else
nilfs_transaction_abort(sb);
- out:
+
return err;
}
unlock_buffer(bh);
goto failed_bh;
}
- bh->b_bdev = NILFS_MDT(inode)->mi_nilfs->ns_bdev;
- bh->b_blocknr = (sector_t)blknum;
- set_buffer_mapped(bh);
+ map_bh(bh, inode->i_sb, (sector_t)blknum);
bh->b_end_io = end_buffer_read_sync;
get_bh(bh);
static int
nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc)
{
- struct inode *inode = container_of(page->mapping,
- struct inode, i_data);
- struct super_block *sb = inode->i_sb;
- struct the_nilfs *nilfs = NILFS_MDT(inode)->mi_nilfs;
- struct nilfs_sb_info *writer = NULL;
+ struct inode *inode;
+ struct super_block *sb;
int err = 0;
redirty_page_for_writepage(wbc, page);
unlock_page(page);
- if (page->mapping->assoc_mapping)
- return 0; /* Do not request flush for shadow page cache */
- if (!sb) {
- down_read(&nilfs->ns_writer_sem);
- writer = nilfs->ns_writer;
- if (!writer) {
- up_read(&nilfs->ns_writer_sem);
- return -EROFS;
- }
- sb = writer->s_super;
- }
+ inode = page->mapping->host;
+ if (!inode)
+ return 0;
+
+ sb = inode->i_sb;
if (wbc->sync_mode == WB_SYNC_ALL)
err = nilfs_construct_segment(sb);
else if (wbc->for_reclaim)
nilfs_flush_segment(sb, inode->i_ino);
- if (writer)
- up_read(&nilfs->ns_writer_sem);
return err;
}
static const struct inode_operations def_mdt_iops;
static const struct file_operations def_mdt_fops;
-/*
- * NILFS2 uses pseudo inodes for meta data files such as DAT, cpfile, sufile,
- * ifile, or gcinodes. This allows the B-tree code and segment constructor
- * to treat them like regular files, and this helps to simplify the
- * implementation.
- * On the other hand, some of the pseudo inodes have an irregular point:
- * They don't have valid inode->i_sb pointer because their lifetimes are
- * longer than those of the super block structs; they may continue for
- * several consecutive mounts/umounts. This would need discussions.
- */
-/**
- * nilfs_mdt_new_common - allocate a pseudo inode for metadata file
- * @nilfs: nilfs object
- * @sb: super block instance the metadata file belongs to
- * @ino: inode number
- * @gfp_mask: gfp mask for data pages
- * @objsz: size of the private object attached to inode->i_private
- */
-struct inode *
-nilfs_mdt_new_common(struct the_nilfs *nilfs, struct super_block *sb,
- ino_t ino, gfp_t gfp_mask, size_t objsz)
+
+int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz)
{
- struct inode *inode = nilfs_alloc_inode_common(nilfs);
+ struct nilfs_mdt_info *mi;
- if (!inode)
- return NULL;
- else {
- struct address_space * const mapping = &inode->i_data;
- struct nilfs_mdt_info *mi;
-
- mi = kzalloc(max(sizeof(*mi), objsz), GFP_NOFS);
- if (!mi) {
- nilfs_destroy_inode(inode);
- return NULL;
- }
- mi->mi_nilfs = nilfs;
- init_rwsem(&mi->mi_sem);
-
- inode->i_sb = sb; /* sb may be NULL for some meta data files */
- inode->i_blkbits = nilfs->ns_blocksize_bits;
- inode->i_flags = 0;
- atomic_set(&inode->i_count, 1);
- inode->i_nlink = 1;
- inode->i_ino = ino;
- inode->i_mode = S_IFREG;
- inode->i_private = mi;
-
-#ifdef INIT_UNUSED_INODE_FIELDS
- atomic_set(&inode->i_writecount, 0);
- inode->i_size = 0;
- inode->i_blocks = 0;
- inode->i_bytes = 0;
- inode->i_generation = 0;
-#ifdef CONFIG_QUOTA
- memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
-#endif
- inode->i_pipe = NULL;
- inode->i_bdev = NULL;
- inode->i_cdev = NULL;
- inode->i_rdev = 0;
-#ifdef CONFIG_SECURITY
- inode->i_security = NULL;
-#endif
- inode->dirtied_when = 0;
-
- INIT_LIST_HEAD(&inode->i_list);
- INIT_LIST_HEAD(&inode->i_sb_list);
- inode->i_state = 0;
-#endif
-
- spin_lock_init(&inode->i_lock);
- mutex_init(&inode->i_mutex);
- init_rwsem(&inode->i_alloc_sem);
-
- mapping->host = NULL; /* instead of inode */
- mapping->flags = 0;
- mapping_set_gfp_mask(mapping, gfp_mask);
- mapping->assoc_mapping = NULL;
- mapping->backing_dev_info = nilfs->ns_bdi;
-
- inode->i_mapping = mapping;
- }
+ mi = kzalloc(max(sizeof(*mi), objsz), GFP_NOFS);
+ if (!mi)
+ return -ENOMEM;
- return inode;
-}
+ init_rwsem(&mi->mi_sem);
+ inode->i_private = mi;
-struct inode *nilfs_mdt_new(struct the_nilfs *nilfs, struct super_block *sb,
- ino_t ino, size_t objsz)
-{
- struct inode *inode;
-
- inode = nilfs_mdt_new_common(nilfs, sb, ino, NILFS_MDT_GFP, objsz);
- if (!inode)
- return NULL;
+ inode->i_mode = S_IFREG;
+ mapping_set_gfp_mask(inode->i_mapping, gfp_mask);
+ inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;
inode->i_op = &def_mdt_iops;
inode->i_fop = &def_mdt_fops;
inode->i_mapping->a_ops = &def_mdt_aops;
- return inode;
+
+ return 0;
}
void nilfs_mdt_set_entry_size(struct inode *inode, unsigned entry_size,
mi->mi_first_entry_offset = DIV_ROUND_UP(header_size, entry_size);
}
-void nilfs_mdt_set_shadow(struct inode *orig, struct inode *shadow)
+static const struct address_space_operations shadow_map_aops = {
+ .sync_page = block_sync_page,
+};
+
+/**
+ * nilfs_mdt_setup_shadow_map - setup shadow map and bind it to metadata file
+ * @inode: inode of the metadata file
+ * @shadow: shadow mapping
+ */
+int nilfs_mdt_setup_shadow_map(struct inode *inode,
+ struct nilfs_shadow_map *shadow)
{
- shadow->i_mapping->assoc_mapping = orig->i_mapping;
- NILFS_I(shadow)->i_btnode_cache.assoc_mapping =
- &NILFS_I(orig)->i_btnode_cache;
+ struct nilfs_mdt_info *mi = NILFS_MDT(inode);
+ struct backing_dev_info *bdi = NILFS_I_NILFS(inode)->ns_bdi;
+
+ INIT_LIST_HEAD(&shadow->frozen_buffers);
+ nilfs_mapping_init_once(&shadow->frozen_data);
+ nilfs_mapping_init(&shadow->frozen_data, bdi, &shadow_map_aops);
+ nilfs_mapping_init_once(&shadow->frozen_btnodes);
+ nilfs_mapping_init(&shadow->frozen_btnodes, bdi, &shadow_map_aops);
+ mi->mi_shadow = shadow;
+ return 0;
}
-static void nilfs_mdt_clear(struct inode *inode)
+/**
+ * nilfs_mdt_save_to_shadow_map - copy bmap and dirty pages to shadow map
+ * @inode: inode of the metadata file
+ */
+int nilfs_mdt_save_to_shadow_map(struct inode *inode)
{
+ struct nilfs_mdt_info *mi = NILFS_MDT(inode);
struct nilfs_inode_info *ii = NILFS_I(inode);
+ struct nilfs_shadow_map *shadow = mi->mi_shadow;
+ int ret;
- invalidate_mapping_pages(inode->i_mapping, 0, -1);
- truncate_inode_pages(inode->i_mapping, 0);
+ ret = nilfs_copy_dirty_pages(&shadow->frozen_data, inode->i_mapping);
+ if (ret)
+ goto out;
+
+ ret = nilfs_copy_dirty_pages(&shadow->frozen_btnodes,
+ &ii->i_btnode_cache);
+ if (ret)
+ goto out;
- if (test_bit(NILFS_I_BMAP, &ii->i_state))
- nilfs_bmap_clear(ii->i_bmap);
- nilfs_btnode_cache_clear(&ii->i_btnode_cache);
+ nilfs_bmap_save(ii->i_bmap, &shadow->bmap_store);
+ out:
+ return ret;
}
-void nilfs_mdt_destroy(struct inode *inode)
+int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh)
{
- struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
+ struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
+ struct buffer_head *bh_frozen;
+ struct page *page;
+ int blkbits = inode->i_blkbits;
+ int ret = -ENOMEM;
+
+ page = grab_cache_page(&shadow->frozen_data, bh->b_page->index);
+ if (!page)
+ return ret;
+
+ if (!page_has_buffers(page))
+ create_empty_buffers(page, 1 << blkbits, 0);
+
+ bh_frozen = nilfs_page_get_nth_block(page, bh_offset(bh) >> blkbits);
+ if (bh_frozen) {
+ if (!buffer_uptodate(bh_frozen))
+ nilfs_copy_buffer(bh_frozen, bh);
+ if (list_empty(&bh_frozen->b_assoc_buffers)) {
+ list_add_tail(&bh_frozen->b_assoc_buffers,
+ &shadow->frozen_buffers);
+ set_buffer_nilfs_redirected(bh);
+ } else {
+ brelse(bh_frozen); /* already frozen */
+ }
+ ret = 0;
+ }
+ unlock_page(page);
+ page_cache_release(page);
+ return ret;
+}
+
+struct buffer_head *
+nilfs_mdt_get_frozen_buffer(struct inode *inode, struct buffer_head *bh)
+{
+ struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
+ struct buffer_head *bh_frozen = NULL;
+ struct page *page;
+ int n;
+
+ page = find_lock_page(&shadow->frozen_data, bh->b_page->index);
+ if (page) {
+ if (page_has_buffers(page)) {
+ n = bh_offset(bh) >> inode->i_blkbits;
+ bh_frozen = nilfs_page_get_nth_block(page, n);
+ }
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ return bh_frozen;
+}
+
+static void nilfs_release_frozen_buffers(struct nilfs_shadow_map *shadow)
+{
+ struct list_head *head = &shadow->frozen_buffers;
+ struct buffer_head *bh;
+
+ while (!list_empty(head)) {
+ bh = list_first_entry(head, struct buffer_head,
+ b_assoc_buffers);
+ list_del_init(&bh->b_assoc_buffers);
+ brelse(bh); /* drop ref-count to make it releasable */
+ }
+}
+
+/**
+ * nilfs_mdt_restore_from_shadow_map - restore dirty pages and bmap state
+ * @inode: inode of the metadata file
+ */
+void nilfs_mdt_restore_from_shadow_map(struct inode *inode)
+{
+ struct nilfs_mdt_info *mi = NILFS_MDT(inode);
+ struct nilfs_inode_info *ii = NILFS_I(inode);
+ struct nilfs_shadow_map *shadow = mi->mi_shadow;
+
+ down_write(&mi->mi_sem);
- if (mdi->mi_palloc_cache)
- nilfs_palloc_destroy_cache(inode);
- nilfs_mdt_clear(inode);
+ if (mi->mi_palloc_cache)
+ nilfs_palloc_clear_cache(inode);
+
+ nilfs_clear_dirty_pages(inode->i_mapping);
+ nilfs_copy_back_pages(inode->i_mapping, &shadow->frozen_data);
+
+ nilfs_clear_dirty_pages(&ii->i_btnode_cache);
+ nilfs_copy_back_pages(&ii->i_btnode_cache, &shadow->frozen_btnodes);
+
+ nilfs_bmap_restore(ii->i_bmap, &shadow->bmap_store);
+
+ up_write(&mi->mi_sem);
+}
+
+/**
+ * nilfs_mdt_clear_shadow_map - truncate pages in shadow map caches
+ * @inode: inode of the metadata file
+ */
+void nilfs_mdt_clear_shadow_map(struct inode *inode)
+{
+ struct nilfs_mdt_info *mi = NILFS_MDT(inode);
+ struct nilfs_shadow_map *shadow = mi->mi_shadow;
- kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
- kfree(mdi);
- nilfs_destroy_inode(inode);
+ down_write(&mi->mi_sem);
+ nilfs_release_frozen_buffers(shadow);
+ truncate_inode_pages(&shadow->frozen_data, 0);
+ truncate_inode_pages(&shadow->frozen_btnodes, 0);
+ up_write(&mi->mi_sem);
}
git.openpandora.org / pandora-kernel.git / blobdiff