| Message ID | 54EEDC4A.8090000@plexistor.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/26/2015 10:41 AM, Boaz Harrosh wrote: > > People systems have been using ramdisk with > smaller-than-page-size blocks in their mkfs. > > The 4K sectors is only important if we will be > using brd with a DAX filesystem. > > So only enable 4K sectors if DAX is configured > > Signed-off-by: Boaz Harrosh <boaz@plexistor.com> > --- > drivers/block/brd.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/block/brd.c b/drivers/block/brd.c > index 6e0775b..e875f12 100644 > --- a/drivers/block/brd.c > +++ b/drivers/block/brd.c > @@ -495,6 +495,7 @@ static struct brd_device *brd_alloc(int i) > blk_queue_max_hw_sectors(brd->brd_queue, 1024); > blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY); > > +#ifdef CONFIG_BLK_DEV_RAM_DAX > /* This is so fdisk will align partitions on 4k, because of > * direct_access API needing 4k alignment, returning a PFN > * (This is only a problem on very small devices <= 4M, > @@ -502,6 +503,7 @@ static struct brd_device *brd_alloc(int i) > * is harmless) > */ Hi Dave I was just thinking should we also do + if (part_show) > blk_queue_physical_block_size(brd->brd_queue, PAGE_SIZE); The rational is that if part_show is off then we are not using partitions at all and then there can be no problems? I'll try to run your tests here. I never test xfs always ext4, maybe I should start to ;-). Actually I do have xfsprogs so why not. But if you could run a quick test as well it could be great. Thanks Boaz <> -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Feb 26, 2015 at 10:41:46AM +0200, Boaz Harrosh wrote: > > People systems have been using ramdisk with > smaller-than-page-size blocks in their mkfs. > > The 4K sectors is only important if we will be > using brd with a DAX filesystem. > > So only enable 4K sectors if DAX is configured 4k sectors are not a problem - we should be handling them fine and because it makes the ramdisk look like a 512e drive, no applications should fail, either. The main "unexpected" part about it was how much of xfstests didn't handle 4k sectors in mkfs output properly. This isn't a problem with the kernel change and so doesn't need fixing. Cheers, Dave.
On 02/27/2015 02:23 AM, Dave Chinner wrote: > On Thu, Feb 26, 2015 at 10:41:46AM +0200, Boaz Harrosh wrote: >> >> People systems have been using ramdisk with >> smaller-than-page-size blocks in their mkfs. >> >> The 4K sectors is only important if we will be >> using brd with a DAX filesystem. >> >> So only enable 4K sectors if DAX is configured > > 4k sectors are not a problem - we should be handling them fine and > because it makes the ramdisk look like a 512e drive, no applications > should fail, either. > > The main "unexpected" part about it was how much of xfstests didn't > handle 4k sectors in mkfs output properly. This isn't a problem with > the kernel change and so doesn't need fixing. > Glad to be of service ;-) Please tell me if there is anything I can help with > Cheers, > Dave. > Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 6e0775b..e875f12 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -495,6 +495,7 @@ static struct brd_device *brd_alloc(int i) blk_queue_max_hw_sectors(brd->brd_queue, 1024); blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY); +#ifdef CONFIG_BLK_DEV_RAM_DAX /* This is so fdisk will align partitions on 4k, because of * direct_access API needing 4k alignment, returning a PFN * (This is only a problem on very small devices <= 4M, @@ -502,6 +503,7 @@ static struct brd_device *brd_alloc(int i) * is harmless) */ blk_queue_physical_block_size(brd->brd_queue, PAGE_SIZE); +#endif brd->brd_queue->limits.discard_granularity = PAGE_SIZE; brd->brd_queue->limits.max_discard_sectors = UINT_MAX;
People systems have been using ramdisk with smaller-than-page-size blocks in their mkfs. The 4K sectors is only important if we will be using brd with a DAX filesystem. So only enable 4K sectors if DAX is configured Signed-off-by: Boaz Harrosh <boaz@plexistor.com> --- drivers/block/brd.c | 2 ++ 1 file changed, 2 insertions(+)