From da019954dd821682d6b2a8330c9c90acb943c456 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Fri, 6 Nov 2015 16:31:54 -0800 Subject: [PATCH] nilfs2: add helper functions to delete blocks from dat file This adds delete functions for data blocks of metadata files using bitmap based allocator. nilfs_palloc_delete_entry_block() deletes an entry block (e.g. block storing dat entries), and nilfs_palloc_delete_bitmap_block() deletes a bitmap block, respectively. These helpers are intended to be used in the successive change on deallocator of block addresses ("nilfs2: free unused dat file blocks during garbage collection"). Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nilfs2/alloc.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c index 5b7ee36f84c7..225b79768865 100644 --- a/fs/nilfs2/alloc.c +++ b/fs/nilfs2/alloc.c @@ -235,6 +235,26 @@ static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff, return ret; } +/** + * nilfs_palloc_delete_block - delete a block on the persistent allocator file + * @inode: inode of metadata file using this allocator + * @blkoff: block offset + * @prev: nilfs_bh_assoc struct of the last used buffer + * @lock: spin lock protecting @prev + */ +static int nilfs_palloc_delete_block(struct inode *inode, unsigned long blkoff, + struct nilfs_bh_assoc *prev, + spinlock_t *lock) +{ + spin_lock(lock); + if (prev->bh && blkoff == prev->blkoff) { + brelse(prev->bh); + prev->bh = NULL; + } + spin_unlock(lock); + return nilfs_mdt_delete_block(inode, blkoff); +} + /** * nilfs_palloc_get_desc_block - get buffer head of a group descriptor block * @inode: inode of metadata file using this allocator @@ -273,6 +293,22 @@ static int nilfs_palloc_get_bitmap_block(struct inode *inode, &cache->prev_bitmap, &cache->lock); } +/** + * nilfs_palloc_delete_bitmap_block - delete a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + */ +static int nilfs_palloc_delete_bitmap_block(struct inode *inode, + unsigned long group) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_delete_block(inode, + nilfs_palloc_bitmap_blkoff(inode, + group), + &cache->prev_bitmap, &cache->lock); +} + /** * nilfs_palloc_get_entry_block - get buffer head of an entry block * @inode: inode of metadata file using this allocator @@ -291,6 +327,20 @@ int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr, &cache->prev_entry, &cache->lock); } +/** + * nilfs_palloc_delete_entry_block - delete an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry + */ +static int nilfs_palloc_delete_entry_block(struct inode *inode, __u64 nr) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_delete_block(inode, + nilfs_palloc_entry_blkoff(inode, nr), + &cache->prev_entry, &cache->lock); +} + /** * nilfs_palloc_block_get_group_desc - get kernel address of a group descriptor * @inode: inode of metadata file using this allocator -- 2.20.1