block: read i_size with i_size_read()

Convert direct reads of an inode's i_size to using i_size_read().

i_size_{read,write} use a seqcount to protect reads from accessing
incomple writes.  Concurrent i_size_write()s require mutual exclussion
to protect the seqcount that is used by i_size_{read,write}.  But
i_size_read() callers do not need to use additional locking.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Mike Snitzer
2010-11-08 14:39:12 +01:00
committed by Jens Axboe
parent 90fdb0b98a
commit 77304d2aba
5 changed files with 18 additions and 18 deletions

View File

@@ -1351,7 +1351,7 @@ static void handle_bad_sector(struct bio *bio)
bdevname(bio->bi_bdev, b),
bio->bi_rw,
(unsigned long long)bio->bi_sector + bio_sectors(bio),
(long long)(bio->bi_bdev->bd_inode->i_size >> 9));
(long long)(i_size_read(bio->bi_bdev->bd_inode) >> 9));
set_bit(BIO_EOF, &bio->bi_flags);
}
@@ -1404,7 +1404,7 @@ static inline int bio_check_eod(struct bio *bio, unsigned int nr_sectors)
return 0;
/* Test device or partition size, when known. */
maxsector = bio->bi_bdev->bd_inode->i_size >> 9;
maxsector = i_size_read(bio->bi_bdev->bd_inode) >> 9;
if (maxsector) {
sector_t sector = bio->bi_sector;

View File

@@ -744,13 +744,13 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
return 0;
case BLKGETSIZE:
size = bdev->bd_inode->i_size;
size = i_size_read(bdev->bd_inode);
if ((size >> 9) > ~0UL)
return -EFBIG;
return compat_put_ulong(arg, size >> 9);
case BLKGETSIZE64_32:
return compat_put_u64(arg, bdev->bd_inode->i_size);
return compat_put_u64(arg, i_size_read(bdev->bd_inode));
case BLKTRACESETUP32:
case BLKTRACESTART: /* compatible */

View File

@@ -125,7 +125,7 @@ static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
start >>= 9;
len >>= 9;
if (start + len > (bdev->bd_inode->i_size >> 9))
if (start + len > (i_size_read(bdev->bd_inode) >> 9))
return -EINVAL;
if (secure)
flags |= BLKDEV_DISCARD_SECURE;
@@ -307,12 +307,12 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
ret = blkdev_reread_part(bdev);
break;
case BLKGETSIZE:
size = bdev->bd_inode->i_size;
size = i_size_read(bdev->bd_inode);
if ((size >> 9) > ~0UL)
return -EFBIG;
return put_ulong(arg, size >> 9);
case BLKGETSIZE64:
return put_u64(arg, bdev->bd_inode->i_size);
return put_u64(arg, i_size_read(bdev->bd_inode));
case BLKTRACESTART:
case BLKTRACESTOP:
case BLKTRACESETUP: