| Message ID | 20171024011007.24855-1-gedwards@ddn.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Oct 23, 2017 at 07:10:07PM -0600, Greg Edwards wrote: > guard_bio_eod() needs to look at the partition capacity, not just the > capacity of the whole device, when determining if truncation is > necessary. > > [ 60.268688] attempt to access beyond end of device > [ 60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506 > [ 60.268693] buffer_io_error: 2 callbacks suppressed > [ 60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read > > Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") > Signed-off-by: Greg Edwards <gedwards@ddn.com> That smells like a nasty source of overhead, especially on SMP boxen...
On Tue, Oct 24, 2017 at 03:16:36AM +0100, Al Viro wrote: > > Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") > > Signed-off-by: Greg Edwards <gedwards@ddn.com> > > That smells like a nasty source of overhead, especially on SMP boxen... We could just use __disk_get_part similar to the partition remapping, or just pass the block_device to guard_bio_eod.
On Tue, Oct 24, 2017 at 09:46:15AM +0200, Christoph Hellwig wrote: > On Tue, Oct 24, 2017 at 03:16:36AM +0100, Al Viro wrote: >>> Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") >>> Signed-off-by: Greg Edwards <gedwards@ddn.com> >> >> That smells like a nasty source of overhead, especially on SMP boxen... > > We could just use __disk_get_part similar to the partition remapping, > or just pass the block_device to guard_bio_eod. Do you have a preference? __disk_get_part would be isolated to guard_bio_eod. If we pass in the block_device, it would also touch all the mpage_bio_submit callers.
diff --git a/fs/buffer.c b/fs/buffer.c index 170df856bdb9..989d3b085efe 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -3055,8 +3055,15 @@ void guard_bio_eod(int op, struct bio *bio) sector_t maxsector; struct bio_vec *bvec = &bio->bi_io_vec[bio->bi_vcnt - 1]; unsigned truncated_bytes; + struct hd_struct *part; + + part = disk_get_part(bio->bi_disk, bio->bi_partno); + if (part) + maxsector = part_nr_sects_read(part); + else + maxsector = get_capacity(bio->bi_disk); + disk_put_part(part); - maxsector = get_capacity(bio->bi_disk); if (!maxsector) return;
guard_bio_eod() needs to look at the partition capacity, not just the capacity of the whole device, when determining if truncation is necessary. [ 60.268688] attempt to access beyond end of device [ 60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506 [ 60.268693] buffer_io_error: 2 callbacks suppressed [ 60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") Signed-off-by: Greg Edwards <gedwards@ddn.com> --- fs/buffer.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)