* [PATCHv6 0/2] loop: enable different logical blocksizes
@ 2017-04-07 6:58 Hannes Reinecke
2017-04-07 6:58 ` [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity Hannes Reinecke
2017-04-07 6:58 ` [PATCHv6 2/2] loop: support 4k physical blocksize Hannes Reinecke
0 siblings, 2 replies; 8+ messages in thread
From: Hannes Reinecke @ 2017-04-07 6:58 UTC (permalink / raw)
To: Jens Axboe; +Cc: Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
Currently the loop driver just simulates 512-byte blocks. When
creating bootable images for virtual machines it might be required
to use a different physical blocksize (eg 4k for S/390 DASD), as
the some bootloaders (like lilo or zipl for S/390) need to know
the physical block addresses of the kernel and initrd.
With this patchset the loop driver will export the logical and
physical blocksize and the current LOOP_SET_STATUS64 ioctl is
extended to set the logical blocksize by re-using the existing
'init' fields, which are currently unused.
As usual, comments and reviews are welcome.
Changes to v1:
- Move LO_FLAGS_BLOCKSIZE definition
- Reshuffle patches
Changes to v2:
- Include reviews from Ming Lei
Changes to v3:
- Include reviews from Christoph
- Merge patches
Changes to v4:
- Add LO_INFO_BLOCKSIZE definition
Changes to v5:
- Rediff to latest upstream
Hannes Reinecke (2):
loop: Remove unused 'bdev' argument from loop_set_capacity
loop: support 4k physical blocksize
drivers/block/loop.c | 40 +++++++++++++++++++++++++++++++++-------
drivers/block/loop.h | 1 +
include/uapi/linux/loop.h | 3 +++
3 files changed, 37 insertions(+), 7 deletions(-)
--
1.8.5.6
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity
2017-04-07 6:58 [PATCHv6 0/2] loop: enable different logical blocksizes Hannes Reinecke
@ 2017-04-07 6:58 ` Hannes Reinecke
2017-04-07 9:37 ` Ming Lei
2017-04-07 6:58 ` [PATCHv6 2/2] loop: support 4k physical blocksize Hannes Reinecke
1 sibling, 1 reply; 8+ messages in thread
From: Hannes Reinecke @ 2017-04-07 6:58 UTC (permalink / raw)
To: Jens Axboe; +Cc: Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
drivers/block/loop.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index cc981f3..81b3900 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1307,7 +1307,7 @@ static int loop_clr_fd(struct loop_device *lo)
return err;
}
-static int loop_set_capacity(struct loop_device *lo, struct block_device *bdev)
+static int loop_set_capacity(struct loop_device *lo)
{
if (unlikely(lo->lo_state != Lo_bound))
return -ENXIO;
@@ -1370,7 +1370,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
case LOOP_SET_CAPACITY:
err = -EPERM;
if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN))
- err = loop_set_capacity(lo, bdev);
+ err = loop_set_capacity(lo);
break;
case LOOP_SET_DIRECT_IO:
err = -EPERM;
--
1.8.5.6
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCHv6 2/2] loop: support 4k physical blocksize
2017-04-07 6:58 [PATCHv6 0/2] loop: enable different logical blocksizes Hannes Reinecke
2017-04-07 6:58 ` [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity Hannes Reinecke
@ 2017-04-07 6:58 ` Hannes Reinecke
2017-04-07 9:34 ` Ming Lei
1 sibling, 1 reply; 8+ messages in thread
From: Hannes Reinecke @ 2017-04-07 6:58 UTC (permalink / raw)
To: Jens Axboe
Cc: Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke, Hannes Reinecke
When generating bootable VM images certain systems (most notably
s390x) require devices with 4k blocksize. This patch implements
a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
blocksize to that of the underlying device, and allow to change
the logical blocksize for up to the physical blocksize.
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++-----
drivers/block/loop.h | 1 +
include/uapi/linux/loop.h | 3 +++
3 files changed, 35 insertions(+), 5 deletions(-)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 81b3900..f098681 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
}
static int
-figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
+figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit,
+ loff_t logical_blocksize)
{
loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
sector_t x = (sector_t)size;
@@ -233,6 +234,12 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
lo->lo_offset = offset;
if (lo->lo_sizelimit != sizelimit)
lo->lo_sizelimit = sizelimit;
+ if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) {
+ lo->lo_logical_blocksize = logical_blocksize;
+ blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize);
+ blk_queue_logical_block_size(lo->lo_queue,
+ lo->lo_logical_blocksize);
+ }
set_capacity(lo->lo_disk, x);
bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
/* let user-space know about the new size */
@@ -814,6 +821,7 @@ static void loop_config_discard(struct loop_device *lo)
struct file *file = lo->lo_backing_file;
struct inode *inode = file->f_mapping->host;
struct request_queue *q = lo->lo_queue;
+ int lo_bits = blksize_bits(lo->lo_logical_blocksize);
/*
* We use punch hole to reclaim the free space used by the
@@ -833,7 +841,7 @@ static void loop_config_discard(struct loop_device *lo)
q->limits.discard_granularity = inode->i_sb->s_blocksize;
q->limits.discard_alignment = 0;
- blk_queue_max_discard_sectors(q, UINT_MAX >> 9);
+ blk_queue_max_discard_sectors(q, UINT_MAX >> lo_bits);
q->limits.discard_zeroes_data = 1;
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
}
@@ -922,6 +930,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
lo->use_dio = false;
lo->lo_blocksize = lo_blocksize;
+ lo->lo_logical_blocksize = 512;
lo->lo_device = bdev;
lo->lo_flags = lo_flags;
lo->lo_backing_file = file;
@@ -1087,6 +1096,7 @@ static int loop_clr_fd(struct loop_device *lo)
int err;
struct loop_func_table *xfer;
kuid_t uid = current_uid();
+ int lo_flags = lo->lo_flags;
if (lo->lo_encrypt_key_size &&
!uid_eq(lo->lo_key_owner, uid) &&
@@ -1119,9 +1129,24 @@ static int loop_clr_fd(struct loop_device *lo)
if (err)
goto exit;
+ if (info->lo_flags & LO_FLAGS_BLOCKSIZE) {
+ lo->lo_flags |= LO_FLAGS_BLOCKSIZE;
+ if (LO_INFO_BLOCKSIZE(info) != 512 &&
+ LO_INFO_BLOCKSIZE(info) != 1024 &&
+ LO_INFO_BLOCKSIZE(info) != 2048 &&
+ LO_INFO_BLOCKSIZE(info) != 4096)
+ return -EINVAL;
+ if (LO_INFO_BLOCKSIZE(info) > lo->lo_blocksize)
+ return -EINVAL;
+ }
+
if (lo->lo_offset != info->lo_offset ||
- lo->lo_sizelimit != info->lo_sizelimit)
- if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) {
+ lo->lo_sizelimit != info->lo_sizelimit ||
+ lo->lo_flags != lo_flags ||
+ ((lo->lo_flags & LO_FLAGS_BLOCKSIZE) &&
+ lo->lo_logical_blocksize != LO_INFO_BLOCKSIZE(info))) {
+ if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit,
+ info->lo_init[0]))
err = -EFBIG;
goto exit;
}
@@ -1312,7 +1337,8 @@ static int loop_set_capacity(struct loop_device *lo)
if (unlikely(lo->lo_state != Lo_bound))
return -ENXIO;
- return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit);
+ return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit,
+ lo->lo_logical_blocksize);
}
static int loop_set_dio(struct loop_device *lo, unsigned long arg)
diff --git a/drivers/block/loop.h b/drivers/block/loop.h
index fb2237c..579f2f7 100644
--- a/drivers/block/loop.h
+++ b/drivers/block/loop.h
@@ -49,6 +49,7 @@ struct loop_device {
struct file * lo_backing_file;
struct block_device *lo_device;
unsigned lo_blocksize;
+ unsigned lo_logical_blocksize;
void *key_data;
gfp_t old_gfp_mask;
diff --git a/include/uapi/linux/loop.h b/include/uapi/linux/loop.h
index c8125ec..a3960f9 100644
--- a/include/uapi/linux/loop.h
+++ b/include/uapi/linux/loop.h
@@ -22,6 +22,7 @@ enum {
LO_FLAGS_AUTOCLEAR = 4,
LO_FLAGS_PARTSCAN = 8,
LO_FLAGS_DIRECT_IO = 16,
+ LO_FLAGS_BLOCKSIZE = 32,
};
#include <asm/posix_types.h> /* for __kernel_old_dev_t */
@@ -59,6 +60,8 @@ struct loop_info64 {
__u64 lo_init[2];
};
+#define LO_INFO_BLOCKSIZE(l) (l)->lo_init[0]
+
/*
* Loop filter types
*/
--
1.8.5.6
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCHv6 2/2] loop: support 4k physical blocksize
2017-04-07 6:58 ` [PATCHv6 2/2] loop: support 4k physical blocksize Hannes Reinecke
@ 2017-04-07 9:34 ` Ming Lei
2017-04-07 9:38 ` Hannes Reinecke
0 siblings, 1 reply; 8+ messages in thread
From: Ming Lei @ 2017-04-07 9:34 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Jens Axboe, Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
On Fri, Apr 07, 2017 at 08:58:58AM +0200, Hannes Reinecke wrote:
> When generating bootable VM images certain systems (most notably
> s390x) require devices with 4k blocksize. This patch implements
> a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
> blocksize to that of the underlying device, and allow to change
> the logical blocksize for up to the physical blocksize.
Actually this UAPI flag is only for setting logical block size.
>
> Signed-off-by: Hannes Reinecke <hare@suse.com>
> ---
> drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++-----
> drivers/block/loop.h | 1 +
> include/uapi/linux/loop.h | 3 +++
> 3 files changed, 35 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> index 81b3900..f098681 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
> }
>
> static int
> -figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
> +figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit,
> + loff_t logical_blocksize)
> {
> loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
> sector_t x = (sector_t)size;
> @@ -233,6 +234,12 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
> lo->lo_offset = offset;
> if (lo->lo_sizelimit != sizelimit)
> lo->lo_sizelimit = sizelimit;
> + if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) {
> + lo->lo_logical_blocksize = logical_blocksize;
> + blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize);
> + blk_queue_logical_block_size(lo->lo_queue,
> + lo->lo_logical_blocksize);
> + }
We can move setting physical block size into loop_set_fd(), and set
512 bytes as default logical block size in loop_set_fd() too.
> set_capacity(lo->lo_disk, x);
> bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
> /* let user-space know about the new size */
> @@ -814,6 +821,7 @@ static void loop_config_discard(struct loop_device *lo)
> struct file *file = lo->lo_backing_file;
> struct inode *inode = file->f_mapping->host;
> struct request_queue *q = lo->lo_queue;
> + int lo_bits = blksize_bits(lo->lo_logical_blocksize);
>
> /*
> * We use punch hole to reclaim the free space used by the
> @@ -833,7 +841,7 @@ static void loop_config_discard(struct loop_device *lo)
>
> q->limits.discard_granularity = inode->i_sb->s_blocksize;
> q->limits.discard_alignment = 0;
> - blk_queue_max_discard_sectors(q, UINT_MAX >> 9);
> + blk_queue_max_discard_sectors(q, UINT_MAX >> lo_bits);
> q->limits.discard_zeroes_data = 1;
> queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
> }
> @@ -922,6 +930,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
>
> lo->use_dio = false;
> lo->lo_blocksize = lo_blocksize;
> + lo->lo_logical_blocksize = 512;
It isn't enough to just this local vaiable as 512 here, since the last
logical block size is still kept in queue's setting.
> lo->lo_device = bdev;
> lo->lo_flags = lo_flags;
> lo->lo_backing_file = file;
> @@ -1087,6 +1096,7 @@ static int loop_clr_fd(struct loop_device *lo)
> int err;
> struct loop_func_table *xfer;
> kuid_t uid = current_uid();
> + int lo_flags = lo->lo_flags;
>
> if (lo->lo_encrypt_key_size &&
> !uid_eq(lo->lo_key_owner, uid) &&
> @@ -1119,9 +1129,24 @@ static int loop_clr_fd(struct loop_device *lo)
> if (err)
> goto exit;
>
> + if (info->lo_flags & LO_FLAGS_BLOCKSIZE) {
> + lo->lo_flags |= LO_FLAGS_BLOCKSIZE;
> + if (LO_INFO_BLOCKSIZE(info) != 512 &&
> + LO_INFO_BLOCKSIZE(info) != 1024 &&
> + LO_INFO_BLOCKSIZE(info) != 2048 &&
> + LO_INFO_BLOCKSIZE(info) != 4096)
> + return -EINVAL;
> + if (LO_INFO_BLOCKSIZE(info) > lo->lo_blocksize)
> + return -EINVAL;
> + }
> +
> if (lo->lo_offset != info->lo_offset ||
> - lo->lo_sizelimit != info->lo_sizelimit)
> - if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) {
> + lo->lo_sizelimit != info->lo_sizelimit ||
> + lo->lo_flags != lo_flags ||
> + ((lo->lo_flags & LO_FLAGS_BLOCKSIZE) &&
> + lo->lo_logical_blocksize != LO_INFO_BLOCKSIZE(info))) {
> + if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit,
> + info->lo_init[0]))
> err = -EFBIG;
> goto exit;
> }
> @@ -1312,7 +1337,8 @@ static int loop_set_capacity(struct loop_device *lo)
> if (unlikely(lo->lo_state != Lo_bound))
> return -ENXIO;
>
> - return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit);
> + return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit,
> + lo->lo_logical_blocksize);
> }
>
> static int loop_set_dio(struct loop_device *lo, unsigned long arg)
> diff --git a/drivers/block/loop.h b/drivers/block/loop.h
> index fb2237c..579f2f7 100644
> --- a/drivers/block/loop.h
> +++ b/drivers/block/loop.h
> @@ -49,6 +49,7 @@ struct loop_device {
> struct file * lo_backing_file;
> struct block_device *lo_device;
> unsigned lo_blocksize;
> + unsigned lo_logical_blocksize;
> void *key_data;
>
> gfp_t old_gfp_mask;
> diff --git a/include/uapi/linux/loop.h b/include/uapi/linux/loop.h
> index c8125ec..a3960f9 100644
> --- a/include/uapi/linux/loop.h
> +++ b/include/uapi/linux/loop.h
> @@ -22,6 +22,7 @@ enum {
> LO_FLAGS_AUTOCLEAR = 4,
> LO_FLAGS_PARTSCAN = 8,
> LO_FLAGS_DIRECT_IO = 16,
> + LO_FLAGS_BLOCKSIZE = 32,
> };
>
> #include <asm/posix_types.h> /* for __kernel_old_dev_t */
> @@ -59,6 +60,8 @@ struct loop_info64 {
> __u64 lo_init[2];
> };
>
> +#define LO_INFO_BLOCKSIZE(l) (l)->lo_init[0]
> +
> /*
> * Loop filter types
> */
> --
> 1.8.5.6
>
--
Ming
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity
2017-04-07 6:58 ` [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity Hannes Reinecke
@ 2017-04-07 9:37 ` Ming Lei
0 siblings, 0 replies; 8+ messages in thread
From: Ming Lei @ 2017-04-07 9:37 UTC (permalink / raw)
To: Hannes Reinecke; +Cc: Jens Axboe, Omar Sandoval, Ming Lei, linux-block
On Fri, Apr 07, 2017 at 08:58:57AM +0200, Hannes Reinecke wrote:
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/block/loop.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> index cc981f3..81b3900 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -1307,7 +1307,7 @@ static int loop_clr_fd(struct loop_device *lo)
> return err;
> }
>
> -static int loop_set_capacity(struct loop_device *lo, struct block_device *bdev)
> +static int loop_set_capacity(struct loop_device *lo)
> {
> if (unlikely(lo->lo_state != Lo_bound))
> return -ENXIO;
> @@ -1370,7 +1370,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
> case LOOP_SET_CAPACITY:
> err = -EPERM;
> if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN))
> - err = loop_set_capacity(lo, bdev);
> + err = loop_set_capacity(lo);
> break;
> case LOOP_SET_DIRECT_IO:
> err = -EPERM;
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCHv6 2/2] loop: support 4k physical blocksize
2017-04-07 9:34 ` Ming Lei
@ 2017-04-07 9:38 ` Hannes Reinecke
2017-04-07 9:52 ` Hannes Reinecke
0 siblings, 1 reply; 8+ messages in thread
From: Hannes Reinecke @ 2017-04-07 9:38 UTC (permalink / raw)
To: Ming Lei
Cc: Jens Axboe, Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
On 04/07/2017 11:34 AM, Ming Lei wrote:
> On Fri, Apr 07, 2017 at 08:58:58AM +0200, Hannes Reinecke wrote:
>> When generating bootable VM images certain systems (most notably
>> s390x) require devices with 4k blocksize. This patch implements
>> a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
>> blocksize to that of the underlying device, and allow to change
>> the logical blocksize for up to the physical blocksize.
>
> Actually this UAPI flag is only for setting logical block size.
>
Hmm? No, we're setting the physical blocksize, too.
Or am I missing something?
>>
>> Signed-off-by: Hannes Reinecke <hare@suse.com>
>> ---
>> drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++-----
>> drivers/block/loop.h | 1 +
>> include/uapi/linux/loop.h | 3 +++
>> 3 files changed, 35 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
>> index 81b3900..f098681 100644
>> --- a/drivers/block/loop.c
>> +++ b/drivers/block/loop.c
>> @@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
>> }
>>
>> static int
>> -figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
>> +figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit,
>> + loff_t logical_blocksize)
>> {
>> loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
>> sector_t x = (sector_t)size;
>> @@ -233,6 +234,12 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
>> lo->lo_offset = offset;
>> if (lo->lo_sizelimit != sizelimit)
>> lo->lo_sizelimit = sizelimit;
>> + if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) {
>> + lo->lo_logical_blocksize = logical_blocksize;
>> + blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize);
>> + blk_queue_logical_block_size(lo->lo_queue,
>> + lo->lo_logical_blocksize);
>> + }
>
> We can move setting physical block size into loop_set_fd(), and set
> 512 bytes as default logical block size in loop_set_fd() too.
>
Okay.
>> set_capacity(lo->lo_disk, x);
>> bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
>> /* let user-space know about the new size */
>> @@ -814,6 +821,7 @@ static void loop_config_discard(struct loop_device *lo)
>> struct file *file = lo->lo_backing_file;
>> struct inode *inode = file->f_mapping->host;
>> struct request_queue *q = lo->lo_queue;
>> + int lo_bits = blksize_bits(lo->lo_logical_blocksize);
>>
>> /*
>> * We use punch hole to reclaim the free space used by the
>> @@ -833,7 +841,7 @@ static void loop_config_discard(struct loop_device *lo)
>>
>> q->limits.discard_granularity = inode->i_sb->s_blocksize;
>> q->limits.discard_alignment = 0;
>> - blk_queue_max_discard_sectors(q, UINT_MAX >> 9);
>> + blk_queue_max_discard_sectors(q, UINT_MAX >> lo_bits);
>> q->limits.discard_zeroes_data = 1;
>> queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
>> }
>> @@ -922,6 +930,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
>>
>> lo->use_dio = false;
>> lo->lo_blocksize = lo_blocksize;
>> + lo->lo_logical_blocksize = 512;
>
> It isn't enough to just this local vaiable as 512 here, since the last
> logical block size is still kept in queue's setting.
>
Right. Will be updating the queue setting, too.
Cheers,
Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@suse.de +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N�rnberg
GF: F. Imend�rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N�rnberg)
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCHv6 2/2] loop: support 4k physical blocksize
2017-04-07 9:38 ` Hannes Reinecke
@ 2017-04-07 9:52 ` Hannes Reinecke
2017-04-07 10:07 ` Ming Lei
0 siblings, 1 reply; 8+ messages in thread
From: Hannes Reinecke @ 2017-04-07 9:52 UTC (permalink / raw)
To: Ming Lei
Cc: Jens Axboe, Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
On 04/07/2017 11:38 AM, Hannes Reinecke wrote:
> On 04/07/2017 11:34 AM, Ming Lei wrote:
>> On Fri, Apr 07, 2017 at 08:58:58AM +0200, Hannes Reinecke wrote:
>>> When generating bootable VM images certain systems (most notably
>>> s390x) require devices with 4k blocksize. This patch implements
>>> a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
>>> blocksize to that of the underlying device, and allow to change
>>> the logical blocksize for up to the physical blocksize.
>>
>> Actually this UAPI flag is only for setting logical block size.
>>
> Hmm? No, we're setting the physical blocksize, too.
> Or am I missing something?
>
>>>
>>> Signed-off-by: Hannes Reinecke <hare@suse.com>
>>> ---
>>> drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++-----
>>> drivers/block/loop.h | 1 +
>>> include/uapi/linux/loop.h | 3 +++
>>> 3 files changed, 35 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
>>> index 81b3900..f098681 100644
>>> --- a/drivers/block/loop.c
>>> +++ b/drivers/block/loop.c
>>> @@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
>>> }
>>>
>>> static int
>>> -figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
>>> +figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit,
>>> + loff_t logical_blocksize)
>>> {
>>> loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
>>> sector_t x = (sector_t)size;
>>> @@ -233,6 +234,12 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
>>> lo->lo_offset = offset;
>>> if (lo->lo_sizelimit != sizelimit)
>>> lo->lo_sizelimit = sizelimit;
>>> + if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) {
>>> + lo->lo_logical_blocksize = logical_blocksize;
>>> + blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize);
>>> + blk_queue_logical_block_size(lo->lo_queue,
>>> + lo->lo_logical_blocksize);
>>> + }
>>
>> We can move setting physical block size into loop_set_fd(), and set
>> 512 bytes as default logical block size in loop_set_fd() too.
>>
> Okay.
>
After thinking about it some more I'm not sure if I agree with that
reasoning.
One of the goals of this patchset is to keep compability with existing
installations.
If we move setting the physical blocksize into loop_set_fd() (which
needs to be called before loop_set_status()) the physical blocksize
would always be set.
Which would induce a user-visible change.
Hence I've formulated my patch to _not_ change the default setup if the
new flag isn't set.
If this is of no concern, however, I can easily modify the patch to
always set the physical blocksize; in fact, that's what I did
originally, but that was deemed bad style.
Cheers,
Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@suse.de +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N�rnberg
GF: F. Imend�rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N�rnberg)
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCHv6 2/2] loop: support 4k physical blocksize
2017-04-07 9:52 ` Hannes Reinecke
@ 2017-04-07 10:07 ` Ming Lei
0 siblings, 0 replies; 8+ messages in thread
From: Ming Lei @ 2017-04-07 10:07 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Jens Axboe, Omar Sandoval, Ming Lei, linux-block, Hannes Reinecke
On Fri, Apr 07, 2017 at 11:52:27AM +0200, Hannes Reinecke wrote:
> On 04/07/2017 11:38 AM, Hannes Reinecke wrote:
> > On 04/07/2017 11:34 AM, Ming Lei wrote:
> >> On Fri, Apr 07, 2017 at 08:58:58AM +0200, Hannes Reinecke wrote:
> >>> When generating bootable VM images certain systems (most notably
> >>> s390x) require devices with 4k blocksize. This patch implements
> >>> a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
> >>> blocksize to that of the underlying device, and allow to change
> >>> the logical blocksize for up to the physical blocksize.
> >>
> >> Actually this UAPI flag is only for setting logical block size.
> >>
> > Hmm? No, we're setting the physical blocksize, too.
> > Or am I missing something?
> >
> >>>
> >>> Signed-off-by: Hannes Reinecke <hare@suse.com>
> >>> ---
> >>> drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++-----
> >>> drivers/block/loop.h | 1 +
> >>> include/uapi/linux/loop.h | 3 +++
> >>> 3 files changed, 35 insertions(+), 5 deletions(-)
> >>>
> >>> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> >>> index 81b3900..f098681 100644
> >>> --- a/drivers/block/loop.c
> >>> +++ b/drivers/block/loop.c
> >>> @@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
> >>> }
> >>>
> >>> static int
> >>> -figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
> >>> +figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit,
> >>> + loff_t logical_blocksize)
> >>> {
> >>> loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
> >>> sector_t x = (sector_t)size;
> >>> @@ -233,6 +234,12 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
> >>> lo->lo_offset = offset;
> >>> if (lo->lo_sizelimit != sizelimit)
> >>> lo->lo_sizelimit = sizelimit;
> >>> + if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) {
> >>> + lo->lo_logical_blocksize = logical_blocksize;
> >>> + blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize);
> >>> + blk_queue_logical_block_size(lo->lo_queue,
> >>> + lo->lo_logical_blocksize);
> >>> + }
> >>
> >> We can move setting physical block size into loop_set_fd(), and set
> >> 512 bytes as default logical block size in loop_set_fd() too.
> >>
> > Okay.
> >
> After thinking about it some more I'm not sure if I agree with that
> reasoning.
>
> One of the goals of this patchset is to keep compability with existing
> installations.
> If we move setting the physical blocksize into loop_set_fd() (which
> needs to be called before loop_set_status()) the physical blocksize
> would always be set.
> Which would induce a user-visible change.
>
> Hence I've formulated my patch to _not_ change the default setup if the
> new flag isn't set.
OK, better to not break current users, :-)
Thanks,
Ming
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2017-04-07 10:07 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-04-07 6:58 [PATCHv6 0/2] loop: enable different logical blocksizes Hannes Reinecke
2017-04-07 6:58 ` [PATCHv6 1/2] loop: Remove unused 'bdev' argument from loop_set_capacity Hannes Reinecke
2017-04-07 9:37 ` Ming Lei
2017-04-07 6:58 ` [PATCHv6 2/2] loop: support 4k physical blocksize Hannes Reinecke
2017-04-07 9:34 ` Ming Lei
2017-04-07 9:38 ` Hannes Reinecke
2017-04-07 9:52 ` Hannes Reinecke
2017-04-07 10:07 ` Ming Lei
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