diff options
Diffstat (limited to 'fs/buffer.c')
| -rw-r--r-- | fs/buffer.c | 188 |
1 files changed, 33 insertions, 155 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index e0ba7b3d077b..2c8df73a233f 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -47,6 +47,7 @@ #include <linux/highmem.h> #include <linux/module.h> #include <linux/completion.h> +#include <linux/compiler.h> #include <asm/uaccess.h> #include <asm/io.h> @@ -548,7 +549,7 @@ static void remove_from_queues(struct buffer_head *bh) spin_unlock(&lru_list_lock); } -struct buffer_head * get_hash_table(kdev_t dev, int block, int size) +struct buffer_head * get_hash_table(kdev_t dev, sector_t block, int size) { struct buffer_head *bh, **p = &hash(dev, block); @@ -1014,7 +1015,7 @@ void invalidate_inode_buffers(struct inode *inode) * 14.02.92: changed it to sync dirty buffers a bit: better performance * when the filesystem starts to get full of dirty blocks (I hope). */ -struct buffer_head * getblk(kdev_t dev, int block, int size) +struct buffer_head * getblk(kdev_t dev, sector_t block, int size) { for (;;) { struct buffer_head * bh; @@ -1988,7 +1989,8 @@ done: goto done; } -int generic_block_bmap(struct address_space *mapping, long block, get_block_t *get_block) +sector_t generic_block_bmap(struct address_space *mapping, sector_t block, + get_block_t *get_block) { struct buffer_head tmp; struct inode *inode = mapping->host; @@ -2001,7 +2003,7 @@ int generic_block_bmap(struct address_space *mapping, long block, get_block_t *g int generic_direct_IO(int rw, struct inode * inode, struct kiobuf * iobuf, unsigned long blocknr, int blocksize, get_block_t * get_block) { int i, nr_blocks, retval; - unsigned long * blocks = iobuf->blocks; + sector_t *blocks = iobuf->blocks; nr_blocks = iobuf->length / blocksize; /* build the blocklist */ @@ -2012,7 +2014,7 @@ int generic_direct_IO(int rw, struct inode * inode, struct kiobuf * iobuf, unsig bh.b_dev = inode->i_dev; bh.b_size = blocksize; - retval = get_block(inode, blocknr, &bh, rw == READ ? 0 : 1); + retval = get_block(inode, blocknr, &bh, rw & 1); if (retval) goto out; @@ -2033,64 +2035,13 @@ int generic_direct_IO(int rw, struct inode * inode, struct kiobuf * iobuf, unsig blocks[i] = bh.b_blocknr; } - retval = brw_kiovec(rw, 1, &iobuf, inode->i_dev, iobuf->blocks, blocksize); + retval = brw_kiovec(rw, 1, &iobuf, inode->i_dev, blocks, blocksize); out: return retval; } /* - * IO completion routine for a buffer_head being used for kiobuf IO: we - * can't dispatch the kiobuf callback until io_count reaches 0. - */ - -static void end_buffer_io_kiobuf(struct buffer_head *bh, int uptodate) -{ - struct kiobuf *kiobuf; - - mark_buffer_uptodate(bh, uptodate); - - kiobuf = bh->b_private; - unlock_buffer(bh); - end_kio_request(kiobuf, uptodate); -} - -/* - * For brw_kiovec: submit a set of buffer_head temporary IOs and wait - * for them to complete. Clean up the buffer_heads afterwards. - */ - -static int wait_kio(int rw, int nr, struct buffer_head *bh[], int size) -{ - int iosize, err; - int i; - struct buffer_head *tmp; - - iosize = 0; - err = 0; - - for (i = nr; --i >= 0; ) { - iosize += size; - tmp = bh[i]; - if (buffer_locked(tmp)) { - wait_on_buffer(tmp); - } - - if (!buffer_uptodate(tmp)) { - /* We are traversing bh'es in reverse order so - clearing iosize on error calculates the - amount of IO before the first error. */ - iosize = 0; - err = -EIO; - } - } - - if (iosize) - return iosize; - return err; -} - -/* * Start I/O on a physical range of kernel memory, defined by a vector * of kiobuf structs (much like a user-space iovec list). * @@ -2101,22 +2052,13 @@ static int wait_kio(int rw, int nr, struct buffer_head *bh[], int size) * It is up to the caller to make sure that there are enough blocks * passed in to completely map the iobufs to disk. */ - -int brw_kiovec(int rw, int nr, struct kiobuf *iovec[], - kdev_t dev, unsigned long b[], int size) +int brw_kiovec(int rw, int nr, struct kiobuf *iovec[], kdev_t dev, sector_t b[], + int size) { - int err; - int length; int transferred; int i; - int bufind; - int pageind; - int bhind; - int offset; - unsigned long blocknr; - struct kiobuf * iobuf = NULL; - struct page * map; - struct buffer_head *tmp, **bhs = NULL; + int err; + struct kiobuf * iobuf; if (!nr) return 0; @@ -2126,8 +2068,7 @@ int brw_kiovec(int rw, int nr, struct kiobuf *iovec[], */ for (i = 0; i < nr; i++) { iobuf = iovec[i]; - if ((iobuf->offset & (size-1)) || - (iobuf->length & (size-1))) + if ((iobuf->offset & (size-1)) || (iobuf->length & (size-1))) return -EINVAL; if (!iobuf->nr_pages) panic("brw_kiovec: iobuf not initialised"); @@ -2136,94 +2077,28 @@ int brw_kiovec(int rw, int nr, struct kiobuf *iovec[], /* * OK to walk down the iovec doing page IO on each page we find. */ - bufind = bhind = transferred = err = 0; for (i = 0; i < nr; i++) { iobuf = iovec[i]; - offset = iobuf->offset; - length = iobuf->length; iobuf->errno = 0; - if (!bhs) - bhs = iobuf->bh; - - for (pageind = 0; pageind < iobuf->nr_pages; pageind++) { - map = iobuf->maplist[pageind]; - if (!map) { - err = -EFAULT; - goto finished; - } - - while (length > 0) { - blocknr = b[bufind++]; - if (blocknr == -1UL) { - if (rw == READ) { - /* there was an hole in the filesystem */ - memset(kmap(map) + offset, 0, size); - flush_dcache_page(map); - kunmap(map); - - transferred += size; - goto skip_block; - } else - BUG(); - } - tmp = bhs[bhind++]; - - tmp->b_size = size; - set_bh_page(tmp, map, offset); - tmp->b_this_page = tmp; - - init_buffer(tmp, end_buffer_io_kiobuf, iobuf); - tmp->b_dev = dev; - tmp->b_blocknr = blocknr; - tmp->b_state = (1 << BH_Mapped) | (1 << BH_Lock) | (1 << BH_Req); - - if (rw == WRITE) { - set_bit(BH_Uptodate, &tmp->b_state); - clear_bit(BH_Dirty, &tmp->b_state); - } else - set_bit(BH_Uptodate, &tmp->b_state); - - atomic_inc(&iobuf->io_count); - submit_bh(rw, tmp); - /* - * Wait for IO if we have got too much - */ - if (bhind >= KIO_MAX_SECTORS) { - kiobuf_wait_for_io(iobuf); /* wake-one */ - err = wait_kio(rw, bhind, bhs, size); - if (err >= 0) - transferred += err; - else - goto finished; - bhind = 0; - } - skip_block: - length -= size; - offset += size; + ll_rw_kio(rw, iobuf, dev, b[i] * (size >> 9)); + } - if (offset >= PAGE_SIZE) { - offset = 0; - break; - } - } /* End of block loop */ - } /* End of page loop */ - } /* End of iovec loop */ - - /* Is there any IO still left to submit? */ - if (bhind) { - kiobuf_wait_for_io(iobuf); /* wake-one */ - err = wait_kio(rw, bhind, bhs, size); - if (err >= 0) - transferred += err; - else - goto finished; + /* + * now they are all submitted, wait for completion + */ + transferred = 0; + err = 0; + for (i = 0; i < nr; i++) { + iobuf = iovec[i]; + kiobuf_wait_for_io(iobuf); + if (iobuf->errno && !err) + err = iobuf->errno; + if (!err) + transferred += iobuf->length; } - finished: - if (transferred) - return transferred; - return err; + return err ? err : transferred; } /* @@ -2238,7 +2113,7 @@ int brw_kiovec(int rw, int nr, struct kiobuf *iovec[], * FIXME: we need a swapper_inode->get_block function to remove * some of the bmap kludges and interface ugliness here. */ -int brw_page(int rw, struct page *page, kdev_t dev, int b[], int size) +int brw_page(int rw, struct page *page, kdev_t dev, sector_t b[], int size) { struct buffer_head *head, *bh; @@ -2326,7 +2201,7 @@ static struct page * grow_dev_page(struct block_device *bdev, unsigned long inde struct buffer_head *bh; page = find_or_create_page(bdev->bd_inode->i_mapping, index, GFP_NOFS); - if (IS_ERR(page)) + if (!page) return NULL; if (!PageLocked(page)) @@ -2490,6 +2365,9 @@ int try_to_free_buffers(struct page * page, unsigned int gfp_mask) { struct buffer_head * tmp, * bh = page->buffers; + BUG_ON(!PageLocked(page)); + BUG_ON(!bh); + cleaned_buffers_try_again: spin_lock(&lru_list_lock); write_lock(&hash_table_lock); |