aboutsummaryrefslogtreecommitdiffstats
path: root/fs/block_dev.c
diff options
context:
space:
mode:
authorPatrick McHardy <kaber@trash.net>2013-03-31 18:10:34 +0200
committerPatrick McHardy <kaber@trash.net>2013-03-31 18:10:34 +0200
commit70711d223510ba1773cfe1d7770a56141c815ff8 (patch)
tree4a71f38a3a554ddecaa31b7d8c6bc49b7d1705b4 /fs/block_dev.c
parentd53b4ed072d9779cdf53582c46436dec06d0961f (diff)
parent19f949f52599ba7c3f67a5897ac6be14bfcb1200 (diff)
Merge tag 'v3.8' of /home/kaber/src/repos/linux
Linux 3.8 Signed-off-by: Patrick McHardy <kaber@trash.net> Conflicts: include/linux/Kbuild include/linux/netlink.h
Diffstat (limited to 'fs/block_dev.c')
-rw-r--r--fs/block_dev.c116
1 files changed, 59 insertions, 57 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c
index c2bbe1fb132..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;
@@ -1578,10 +1525,12 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct file *file = iocb->ki_filp;
+ struct blk_plug plug;
ssize_t ret;
BUG_ON(iocb->ki_pos != pos);
+ blk_start_plug(&plug);
ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
if (ret > 0 || ret == -EIOCBQUEUED) {
ssize_t err;
@@ -1590,10 +1539,27 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
if (err < 0 && ret > 0)
ret = err;
}
+ blk_finish_plug(&plug);
return ret;
}
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.
@@ -1624,7 +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,
@@ -1710,3 +1676,39 @@ int __invalidate_device(struct block_device *bdev, bool kill_dirty)
return res;
}
EXPORT_SYMBOL(__invalidate_device);
+
+void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
+{
+ struct inode *inode, *old_inode = NULL;
+
+ spin_lock(&inode_sb_list_lock);
+ list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
+ struct address_space *mapping = inode->i_mapping;
+
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
+ mapping->nrpages == 0) {
+ spin_unlock(&inode->i_lock);
+ continue;
+ }
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(&inode_sb_list_lock);
+ /*
+ * We hold a reference to 'inode' so it couldn't have been
+ * removed from s_inodes list while we dropped the
+ * inode_sb_list_lock. We cannot iput the inode now as we can
+ * be holding the last reference and we cannot iput it under
+ * inode_sb_list_lock. So we keep the reference and iput it
+ * later.
+ */
+ iput(old_inode);
+ old_inode = inode;
+
+ func(I_BDEV(inode), arg);
+
+ spin_lock(&inode_sb_list_lock);
+ }
+ spin_unlock(&inode_sb_list_lock);
+ iput(old_inode);
+}