diff options
Diffstat (limited to 'fs/block_dev.c')
| -rw-r--r-- | fs/block_dev.c | 77 |
1 files changed, 20 insertions, 57 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index 38e721b35d4..172f8491a2b 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -70,19 +70,6 @@ static void bdev_inode_switch_bdi(struct inode *inode, spin_unlock(&dst->wb.list_lock); } -sector_t blkdev_max_block(struct block_device *bdev) -{ - sector_t retval = ~((sector_t)0); - loff_t sz = i_size_read(bdev->bd_inode); - - if (sz) { - unsigned int size = block_size(bdev); - unsigned int sizebits = blksize_bits(size); - retval = (sz >> sizebits); - } - return retval; -} - /* Kill _all_ buffers and pagecache , dirty or not.. */ void kill_bdev(struct block_device *bdev) { @@ -163,52 +150,12 @@ static int blkdev_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh, int create) { - if (iblock >= blkdev_max_block(I_BDEV(inode))) { - if (create) - return -EIO; - - /* - * for reads, we're just trying to fill a partial page. - * return a hole, they will have to call get_block again - * before they can fill it, and they will get -EIO at that - * time - */ - return 0; - } bh->b_bdev = I_BDEV(inode); bh->b_blocknr = iblock; set_buffer_mapped(bh); return 0; } -static int -blkdev_get_blocks(struct inode *inode, sector_t iblock, - struct buffer_head *bh, int create) -{ - sector_t end_block = blkdev_max_block(I_BDEV(inode)); - unsigned long max_blocks = bh->b_size >> inode->i_blkbits; - - if ((iblock + max_blocks) > end_block) { - max_blocks = end_block - iblock; - if ((long)max_blocks <= 0) { - if (create) - return -EIO; /* write fully beyond EOF */ - /* - * It is a read which is fully beyond EOF. We return - * a !buffer_mapped buffer - */ - max_blocks = 0; - } - } - - bh->b_bdev = I_BDEV(inode); - bh->b_blocknr = iblock; - bh->b_size = max_blocks << inode->i_blkbits; - if (max_blocks) - set_buffer_mapped(bh); - return 0; -} - static ssize_t blkdev_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, loff_t offset, unsigned long nr_segs) @@ -217,7 +164,7 @@ blkdev_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, struct inode *inode = file->f_mapping->host; return __blockdev_direct_IO(rw, iocb, inode, I_BDEV(inode), iov, offset, - nr_segs, blkdev_get_blocks, NULL, NULL, 0); + nr_segs, blkdev_get_block, NULL, NULL, 0); } int __sync_blockdev(struct block_device *bdev, int wait) @@ -374,7 +321,7 @@ static int blkdev_write_end(struct file *file, struct address_space *mapping, * for a block special file file->f_path.dentry->d_inode->i_size is zero * so we compute the size by hand (just as in block_read/write above) */ -static loff_t block_llseek(struct file *file, loff_t offset, int origin) +static loff_t block_llseek(struct file *file, loff_t offset, int whence) { struct inode *bd_inode = file->f_mapping->host; loff_t size; @@ -384,7 +331,7 @@ static loff_t block_llseek(struct file *file, loff_t offset, int origin) size = i_size_read(bd_inode); retval = -EINVAL; - switch (origin) { + switch (whence) { case SEEK_END: offset += size; break; @@ -1597,6 +1544,22 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, } EXPORT_SYMBOL_GPL(blkdev_aio_write); +static ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + struct file *file = iocb->ki_filp; + struct inode *bd_inode = file->f_mapping->host; + loff_t size = i_size_read(bd_inode); + + if (pos >= size) + return 0; + + size -= pos; + if (size < INT_MAX) + nr_segs = iov_shorten((struct iovec *)iov, nr_segs, size); + return generic_file_aio_read(iocb, iov, nr_segs, pos); +} + /* * Try to release a page associated with block device when the system * is under memory pressure. @@ -1627,7 +1590,7 @@ const struct file_operations def_blk_fops = { .llseek = block_llseek, .read = do_sync_read, .write = do_sync_write, - .aio_read = generic_file_aio_read, + .aio_read = blkdev_aio_read, .aio_write = blkdev_aio_write, .mmap = generic_file_mmap, .fsync = blkdev_fsync, |