X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Fbuffer_head.h;h=08033f3ac4efea69b9f69814a50ed741dbdb49f9;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=6d70bd5393e67e8b238f68e0f5ee19c153ee0987;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 6d70bd539..08033f3ac 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -18,6 +19,9 @@ enum bh_state_bits { BH_Dirty, /* Is dirty */ BH_Lock, /* Is locked */ BH_Req, /* Has been submitted for I/O */ + BH_Uptodate_Lock,/* Used by the first bh in a page, to serialise + * IO completion of other buffers in the page + */ BH_Mapped, /* Has a disk mapping */ BH_New, /* Disk mapping was newly created by get_block */ @@ -26,6 +30,8 @@ enum bh_state_bits { BH_Delay, /* Buffer is not yet allocated on disk */ BH_Boundary, /* Block is followed by a discontiguity */ BH_Write_EIO, /* I/O error on write */ + BH_Ordered, /* ordered write */ + BH_Eopnotsupp, /* operation not supported (barrier) */ BH_PrivateStart,/* not a state bit, but the first bit available * for private allocation by other entities @@ -40,25 +46,28 @@ struct address_space; typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate); /* - * Keep related fields in common cachelines. The most commonly accessed - * field (b_state) goes at the start so the compiler does not generate - * indexed addressing for it. + * Historically, a buffer_head was used to map a single block + * within a page, and of course as the unit of I/O through the + * filesystem and block layers. Nowadays the basic I/O unit + * is the bio, and buffer_heads are used for extracting block + * mappings (via a get_block_t call), for tracking state within + * a page (via a page_mapping) and for wrapping bio submission + * for backward compatibility reasons (e.g. submit_bh). */ struct buffer_head { - /* First cache line: */ unsigned long b_state; /* buffer state bitmap (see above) */ - atomic_t b_count; /* users using this block */ struct buffer_head *b_this_page;/* circular list of page's buffers */ struct page *b_page; /* the page this bh is mapped to */ - sector_t b_blocknr; /* block number */ - u32 b_size; /* block size */ - char *b_data; /* pointer to data block */ + sector_t b_blocknr; /* start block number */ + size_t b_size; /* size of mapping */ + char *b_data; /* pointer to data within the page */ struct block_device *b_bdev; bh_end_io_t *b_end_io; /* I/O completion */ void *b_private; /* reserved for b_end_io */ struct list_head b_assoc_buffers; /* associated with another mapping */ + atomic_t b_count; /* users using this buffer_head */ }; /* @@ -74,7 +83,7 @@ static inline void clear_buffer_##name(struct buffer_head *bh) \ { \ clear_bit(BH_##bit, &(bh)->b_state); \ } \ -static inline int buffer_##name(struct buffer_head *bh) \ +static inline int buffer_##name(const struct buffer_head *bh) \ { \ return test_bit(BH_##bit, &(bh)->b_state); \ } @@ -110,7 +119,9 @@ BUFFER_FNS(Async_Read, async_read) BUFFER_FNS(Async_Write, async_write) BUFFER_FNS(Delay, delay) BUFFER_FNS(Boundary, boundary) -BUFFER_FNS(Write_EIO,write_io_error) +BUFFER_FNS(Write_EIO, write_io_error) +BUFFER_FNS(Ordered, ordered) +BUFFER_FNS(Eopnotsupp, eopnotsupp) #define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK) #define touch_buffer(bh) mark_page_accessed(bh->b_page) @@ -118,8 +129,8 @@ BUFFER_FNS(Write_EIO,write_io_error) /* If we *know* page->private refers to buffer_heads */ #define page_buffers(page) \ ({ \ - BUG_ON(!PagePrivate(page)); \ - ((struct buffer_head *)(page)->private); \ + BUG_ON(!PagePrivate(page)); \ + ((struct buffer_head *)page_private(page)); \ }) #define page_has_buffers(page) PagePrivate(page) @@ -132,6 +143,8 @@ void init_buffer(struct buffer_head *, bh_end_io_t *, void *); void set_bh_page(struct buffer_head *bh, struct page *page, unsigned long offset); int try_to_free_buffers(struct page *); +struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, + int retry); void create_empty_buffers(struct page *, unsigned long, unsigned long b_state); void end_buffer_read_sync(struct buffer_head *bh, int uptodate); @@ -139,23 +152,18 @@ void end_buffer_write_sync(struct buffer_head *bh, int uptodate); void end_buffer_async_write(struct buffer_head *bh, int uptodate); /* Things to do with buffers at mapping->private_list */ -void buffer_insert_list(spinlock_t *lock, - struct buffer_head *, struct list_head *); void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode); int inode_has_buffers(struct inode *); void invalidate_inode_buffers(struct inode *); int remove_inode_buffers(struct inode *inode); -int fsync_buffers_list(spinlock_t *lock, struct list_head *); int sync_mapping_buffers(struct address_space *mapping); void unmap_underlying_metadata(struct block_device *bdev, sector_t block); -void mark_buffer_async_read(struct buffer_head *bh); void mark_buffer_async_write(struct buffer_head *bh); void invalidate_bdev(struct block_device *, int); int sync_blockdev(struct block_device *bdev); void __wait_on_buffer(struct buffer_head *); wait_queue_head_t *bh_waitq_head(struct buffer_head *bh); -void wake_up_buffer(struct buffer_head *bh); int fsync_bdev(struct block_device *); struct super_block *freeze_bdev(struct block_device *); void thaw_bdev(struct block_device *, struct super_block *); @@ -167,13 +175,13 @@ void __brelse(struct buffer_head *); void __bforget(struct buffer_head *); void __breadahead(struct block_device *, sector_t block, int size); struct buffer_head *__bread(struct block_device *, sector_t block, int size); -struct buffer_head *alloc_buffer_head(int gfp_flags); +struct buffer_head *alloc_buffer_head(gfp_t gfp_flags); void free_buffer_head(struct buffer_head * bh); void FASTCALL(unlock_buffer(struct buffer_head *bh)); void FASTCALL(__lock_buffer(struct buffer_head *bh)); void ll_rw_block(int, int, struct buffer_head * bh[]); -void sync_dirty_buffer(struct buffer_head *bh); -void submit_bh(int, struct buffer_head *); +int sync_dirty_buffer(struct buffer_head *bh); +int submit_bh(int, struct buffer_head *); void write_boundary_block(struct block_device *bdev, sector_t bblock, unsigned blocksize); @@ -183,17 +191,20 @@ extern int buffer_heads_over_limit; * Generic address_space_operations implementations for buffer_head-backed * address_spaces. */ -int try_to_release_page(struct page * page, int gfp_mask); -int block_invalidatepage(struct page *page, unsigned long offset); +int try_to_release_page(struct page * page, gfp_t gfp_mask); +void block_invalidatepage(struct page *page, unsigned long offset); +void do_invalidatepage(struct page *page, unsigned long offset); int block_write_full_page(struct page *page, get_block_t *get_block, struct writeback_control *wbc); int block_read_full_page(struct page*, get_block_t*); int block_prepare_write(struct page*, unsigned, unsigned, get_block_t*); int cont_prepare_write(struct page*, unsigned, unsigned, get_block_t*, loff_t *); -int generic_cont_expand(struct inode *inode, loff_t size) ; +int generic_cont_expand(struct inode *inode, loff_t size); +int generic_cont_expand_simple(struct inode *inode, loff_t size); int block_commit_write(struct page *page, unsigned from, unsigned to); -int block_sync_page(struct page *); +void block_sync_page(struct page *); +void flush_inode_pages (struct inode * inode); sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *); int generic_commit_write(struct file *, struct page *, unsigned, unsigned); int block_truncate_page(struct address_space *, loff_t, get_block_t *); @@ -201,17 +212,22 @@ int file_fsync(struct file *, struct dentry *, int); int nobh_prepare_write(struct page*, unsigned, unsigned, get_block_t*); int nobh_commit_write(struct file *, struct page *, unsigned, unsigned); int nobh_truncate_page(struct address_space *, loff_t); - -#define OSYNC_METADATA (1<<0) -#define OSYNC_DATA (1<<1) -#define OSYNC_INODE (1<<2) -int generic_osync_inode(struct inode *, struct address_space *, int); +int nobh_writepage(struct page *page, get_block_t *get_block, + struct writeback_control *wbc); /* * inline definitions */ +static inline void attach_page_buffers(struct page *page, + struct buffer_head *head) +{ + page_cache_get(page); + SetPagePrivate(page); + set_page_private(page, (unsigned long)head); +} + static inline void get_bh(struct buffer_head *bh) { atomic_inc(&bh->b_count); @@ -265,6 +281,7 @@ map_bh(struct buffer_head *bh, struct super_block *sb, sector_t block) set_buffer_mapped(bh); bh->b_bdev = sb->s_bdev; bh->b_blocknr = block; + bh->b_size = sb->s_blocksize; } /* @@ -274,12 +291,14 @@ map_bh(struct buffer_head *bh, struct super_block *sb, sector_t block) */ static inline void wait_on_buffer(struct buffer_head *bh) { + might_sleep(); if (buffer_locked(bh) || atomic_read(&bh->b_count) == 0) __wait_on_buffer(bh); } static inline void lock_buffer(struct buffer_head *bh) { + might_sleep(); if (test_set_buffer_locked(bh)) __lock_buffer(bh); }