| From 35f2a591192d0a5d9f7fc696869c76f0b8e49c3d Mon Sep 17 00:00:00 2001 |
| From: NeilBrown <neilb@suse.de> |
| Date: Tue, 20 Apr 2010 14:13:34 +1000 |
| Subject: md/raid5: allow for more than 2^31 chunks. |
| |
| From: NeilBrown <neilb@suse.de> |
| |
| commit 35f2a591192d0a5d9f7fc696869c76f0b8e49c3d upstream. |
| |
| With many large drives and small chunk sizes it is possible |
| to create a RAID5 with more than 2^31 chunks. Make sure this |
| works. |
| |
| Reported-by: Brett King <king.br@gmail.com> |
| Signed-off-by: NeilBrown <neilb@suse.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/md/raid5.c | 19 +++++++------------ |
| 1 file changed, 7 insertions(+), 12 deletions(-) |
| |
| --- a/drivers/md/raid5.c |
| +++ b/drivers/md/raid5.c |
| @@ -1649,8 +1649,8 @@ static sector_t raid5_compute_sector(rai |
| int previous, int *dd_idx, |
| struct stripe_head *sh) |
| { |
| - long stripe; |
| - unsigned long chunk_number; |
| + sector_t stripe; |
| + sector_t chunk_number; |
| unsigned int chunk_offset; |
| int pd_idx, qd_idx; |
| int ddf_layout = 0; |
| @@ -1670,17 +1670,12 @@ static sector_t raid5_compute_sector(rai |
| */ |
| chunk_offset = sector_div(r_sector, sectors_per_chunk); |
| chunk_number = r_sector; |
| - BUG_ON(r_sector != chunk_number); |
| |
| /* |
| * Compute the stripe number |
| */ |
| - stripe = chunk_number / data_disks; |
| - |
| - /* |
| - * Compute the data disk and parity disk indexes inside the stripe |
| - */ |
| - *dd_idx = chunk_number % data_disks; |
| + stripe = chunk_number; |
| + *dd_idx = sector_div(stripe, data_disks); |
| |
| /* |
| * Select the parity disk based on the user selected algorithm. |
| @@ -1869,14 +1864,14 @@ static sector_t compute_blocknr(struct s |
| : conf->algorithm; |
| sector_t stripe; |
| int chunk_offset; |
| - int chunk_number, dummy1, dd_idx = i; |
| + sector_t chunk_number; |
| + int dummy1, dd_idx = i; |
| sector_t r_sector; |
| struct stripe_head sh2; |
| |
| |
| chunk_offset = sector_div(new_sector, sectors_per_chunk); |
| stripe = new_sector; |
| - BUG_ON(new_sector != stripe); |
| |
| if (i == sh->pd_idx) |
| return 0; |
| @@ -1969,7 +1964,7 @@ static sector_t compute_blocknr(struct s |
| } |
| |
| chunk_number = stripe * data_disks + i; |
| - r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; |
| + r_sector = chunk_number * sectors_per_chunk + chunk_offset; |
| |
| check = raid5_compute_sector(conf, r_sector, |
| previous, &dummy1, &sh2); |