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)
{
int set_blocksize(struct block_device *bdev, int size)
{
- struct address_space *mapping;
-
/* Size must be a power of two, and between 512 and PAGE_SIZE */
if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
return -EINVAL;
if (size < bdev_logical_block_size(bdev))
return -EINVAL;
- /* Prevent starting I/O or mapping the device */
- percpu_down_write(&bdev->bd_block_size_semaphore);
-
- /* Check that the block device is not memory mapped */
- mapping = bdev->bd_inode->i_mapping;
- mutex_lock(&mapping->i_mmap_mutex);
- if (mapping_mapped(mapping)) {
- mutex_unlock(&mapping->i_mmap_mutex);
- percpu_up_write(&bdev->bd_block_size_semaphore);
- return -EBUSY;
- }
- mutex_unlock(&mapping->i_mmap_mutex);
-
/* Don't change the size if it is same as current */
if (bdev->bd_block_size != size) {
sync_blockdev(bdev);
bdev->bd_inode->i_blkbits = blksize_bits(size);
kill_bdev(bdev);
}
-
- percpu_up_write(&bdev->bd_block_size_semaphore);
-
return 0;
}
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)
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)
struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
if (!ei)
return NULL;
-
- if (unlikely(percpu_init_rwsem(&ei->bdev.bd_block_size_semaphore))) {
- kmem_cache_free(bdev_cachep, ei);
- return NULL;
- }
-
return &ei->vfs_inode;
}
struct inode *inode = container_of(head, struct inode, i_rcu);
struct bdev_inode *bdi = BDEV_I(inode);
- percpu_free_rwsem(&bdi->bdev.bd_block_size_semaphore);
-
kmem_cache_free(bdev_cachep, bdi);
}
return blkdev_ioctl(bdev, mode, cmd, arg);
}
-ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
-{
- ssize_t ret;
- struct block_device *bdev = I_BDEV(iocb->ki_filp->f_mapping->host);
-
- percpu_down_read(&bdev->bd_block_size_semaphore);
-
- ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
-
- percpu_up_read(&bdev->bd_block_size_semaphore);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(blkdev_aio_read);
-
/*
* Write data to the block device. Only intended for the block device itself
* and the raw driver which basically is a fake block device.
unsigned long nr_segs, loff_t pos)
{
struct file *file = iocb->ki_filp;
- struct block_device *bdev = I_BDEV(file->f_mapping->host);
struct blk_plug plug;
ssize_t ret;
BUG_ON(iocb->ki_pos != pos);
blk_start_plug(&plug);
-
- percpu_down_read(&bdev->bd_block_size_semaphore);
-
ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
if (ret > 0 || ret == -EIOCBQUEUED) {
ssize_t err;
if (err < 0 && ret > 0)
ret = err;
}
-
- percpu_up_read(&bdev->bd_block_size_semaphore);
-
blk_finish_plug(&plug);
-
return ret;
}
EXPORT_SYMBOL_GPL(blkdev_aio_write);
-static int blkdev_mmap(struct file *file, struct vm_area_struct *vma)
-{
- int ret;
- struct block_device *bdev = I_BDEV(file->f_mapping->host);
-
- percpu_down_read(&bdev->bd_block_size_semaphore);
-
- ret = generic_file_mmap(file, vma);
-
- percpu_up_read(&bdev->bd_block_size_semaphore);
-
- return ret;
-}
-
-static ssize_t blkdev_splice_read(struct file *file, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- ssize_t ret;
- struct block_device *bdev = I_BDEV(file->f_mapping->host);
-
- percpu_down_read(&bdev->bd_block_size_semaphore);
-
- ret = generic_file_splice_read(file, ppos, pipe, len, flags);
-
- percpu_up_read(&bdev->bd_block_size_semaphore);
-
- return ret;
-}
-
-static ssize_t blkdev_splice_write(struct pipe_inode_info *pipe,
- struct file *file, loff_t *ppos, size_t len,
- unsigned int flags)
+static ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
{
- ssize_t ret;
- struct block_device *bdev = I_BDEV(file->f_mapping->host);
-
- percpu_down_read(&bdev->bd_block_size_semaphore);
-
- ret = generic_file_splice_write(pipe, file, ppos, len, flags);
+ struct file *file = iocb->ki_filp;
+ struct inode *bd_inode = file->f_mapping->host;
+ loff_t size = i_size_read(bd_inode);
- percpu_up_read(&bdev->bd_block_size_semaphore);
+ if (pos >= size)
+ return 0;
- return ret;
+ 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.
.llseek = block_llseek,
.read = do_sync_read,
.write = do_sync_write,
- .aio_read = blkdev_aio_read,
+ .aio_read = blkdev_aio_read,
.aio_write = blkdev_aio_write,
- .mmap = blkdev_mmap,
+ .mmap = generic_file_mmap,
.fsync = blkdev_fsync,
.unlocked_ioctl = block_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = compat_blkdev_ioctl,
#endif
- .splice_read = blkdev_splice_read,
- .splice_write = blkdev_splice_write,
+ .splice_read = generic_file_splice_read,
+ .splice_write = generic_file_splice_write,
};
int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg)
projects / can-eth-gw-linux.git / blobdiff