From mboxrd@z Thu Jan  1 00:00:00 1970
From: Li Dongyang <jerry87905@gmail.com>
Subject: Re: [PATCH V2 3/3] xen-blkback: handle trim request in
	backend driver
Date: Mon, 22 Aug 2011 17:43:28 +0800
Message-ID: <CAKH3R49tQ1y6uyPFDQ0QFRPa3vwt=iuYLUMQxGB1GcXLS_zO6A@mail.gmail.com>
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	<20110818145611.GC23922@dumpdata.com>
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To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: xen-devel@lists.xensource.com, owen.smith@citrix.com, JBeulich@novell.com
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On Thu, Aug 18, 2011 at 10:56 PM, Konrad Rzeszutek Wilk
<konrad.wilk@oracle.com> wrote:
> On Thu, Aug 18, 2011 at 05:34:31PM +0800, Li Dongyang wrote:
>> Now blkback driver can handle the trim request from guest, we will
>> forward the request to phy device if it really has trim support, or we'l=
l
>> punch a hole on the image file.
>>
>> Signed-off-by: Li Dongyang <lidongyang@novell.com>
>> ---
>> =A0drivers/block/xen-blkback/blkback.c | =A0 85 ++++++++++++++++++++++++=
+++++------
>> =A0drivers/block/xen-blkback/common.h =A0| =A0 =A04 +-
>> =A0drivers/block/xen-blkback/xenbus.c =A0| =A0 61 ++++++++++++++++++++++=
+++
>> =A03 files changed, 135 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blk=
back/blkback.c
>> index 2330a9a..5acc37a 100644
>> --- a/drivers/block/xen-blkback/blkback.c
>> +++ b/drivers/block/xen-blkback/blkback.c
>> @@ -39,6 +39,9 @@
>> =A0#include <linux/list.h>
>> =A0#include <linux/delay.h>
>> =A0#include <linux/freezer.h>
>> +#include <linux/loop.h>
>> +#include <linux/falloc.h>
>> +#include <linux/fs.h>
>>
>> =A0#include <xen/events.h>
>> =A0#include <xen/page.h>
>> @@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id=
)
>>
>> =A0static void print_stats(struct xen_blkif *blkif)
>> =A0{
>> - =A0 =A0 pr_info("xen-blkback (%s): oo %3d =A0| =A0rd %4d =A0| =A0wr %4=
d =A0| =A0f %4d\n",
>> + =A0 =A0 pr_info("xen-blkback (%s): oo %3d =A0| =A0rd %4d =A0| =A0wr %4=
d =A0| =A0f %4d"
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0" =A0| =A0tr %4d\n",
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0current->comm, blkif->st_oo_req,
>> - =A0 =A0 =A0 =A0 =A0 =A0 =A0blkif->st_rd_req, blkif->st_wr_req, blkif->=
st_f_req);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0blkif->st_rd_req, blkif->st_wr_req,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0blkif->st_f_req, blkif->st_tr_req);
>> =A0 =A0 =A0 blkif->st_print =3D jiffies + msecs_to_jiffies(10 * 1000);
>> =A0 =A0 =A0 blkif->st_rd_req =3D 0;
>> =A0 =A0 =A0 blkif->st_wr_req =3D 0;
>> =A0 =A0 =A0 blkif->st_oo_req =3D 0;
>> + =A0 =A0 blkif->st_tr_req =3D 0;
>> =A0}
>>
>> =A0int xen_blkif_schedule(void *arg)
>> @@ -563,6 +569,10 @@ static int dispatch_rw_block_io(struct xen_blkif *b=
lkif,
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 blkif->st_f_req++;
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 operation =3D WRITE_FLUSH;
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
>> + =A0 =A0 case BLKIF_OP_TRIM:
>> + =A0 =A0 =A0 =A0 =A0 =A0 blkif->st_tr_req++;
>> + =A0 =A0 =A0 =A0 =A0 =A0 operation =3D REQ_DISCARD;
>> + =A0 =A0 =A0 =A0 =A0 =A0 break;
>> =A0 =A0 =A0 case BLKIF_OP_WRITE_BARRIER:
>> =A0 =A0 =A0 default:
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 operation =3D 0; /* make gcc happy */
>> @@ -572,7 +582,7 @@ static int dispatch_rw_block_io(struct xen_blkif *bl=
kif,
>>
>> =A0 =A0 =A0 /* Check that the number of segments is sane. */
>> =A0 =A0 =A0 nseg =3D req->nr_segments;
>> - =A0 =A0 if (unlikely(nseg =3D=3D 0 && operation !=3D WRITE_FLUSH) ||
>> + =A0 =A0 if (unlikely(nseg =3D=3D 0 && operation !=3D (WRITE_FLUSH | RE=
Q_DISCARD)) ||
>> =A0 =A0 =A0 =A0 =A0 unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) {
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 pr_debug(DRV_PFX "Bad number of segments in =
request (%d)\n",
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0nseg);
>> @@ -627,10 +637,13 @@ static int dispatch_rw_block_io(struct xen_blkif *=
blkif,
>> =A0 =A0 =A0 =A0* the hypercall to unmap the grants - that is all done in
>> =A0 =A0 =A0 =A0* xen_blkbk_unmap.
>> =A0 =A0 =A0 =A0*/
>> - =A0 =A0 if (xen_blkbk_map(req, pending_req, seg))
>> + =A0 =A0 if (operation !=3D BLKIF_OP_TRIM && xen_blkbk_map(req, pending=
_req, seg))
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 goto fail_flush;
>>
>> - =A0 =A0 /* This corresponding xen_blkif_put is done in __end_block_io_=
op */
>> + =A0 =A0 /*
>> + =A0 =A0 =A0* This corresponding xen_blkif_put is done in __end_block_i=
o_op, or
>> + =A0 =A0 =A0* below if we are handling a BLKIF_OP_TRIM.
>> + =A0 =A0 =A0*/
>> =A0 =A0 =A0 xen_blkif_get(blkif);
>>
>> =A0 =A0 =A0 for (i =3D 0; i < nseg; i++) {
>> @@ -654,18 +667,62 @@ static int dispatch_rw_block_io(struct xen_blkif *=
blkif,
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 preq.sector_number +=3D seg[i].nsec;
>> =A0 =A0 =A0 }
>>
>> - =A0 =A0 /* This will be hit if the operation was a flush. */
>> + =A0 =A0 /* This will be hit if the operation was a flush or trim. */
>> =A0 =A0 =A0 if (!bio) {
>> - =A0 =A0 =A0 =A0 =A0 =A0 BUG_ON(operation !=3D WRITE_FLUSH);
>> + =A0 =A0 =A0 =A0 =A0 =A0 BUG_ON(operation !=3D (WRITE_FLUSH | REQ_DISCA=
RD));
>>
>> - =A0 =A0 =A0 =A0 =A0 =A0 bio =3D bio_alloc(GFP_KERNEL, 0);
>> - =A0 =A0 =A0 =A0 =A0 =A0 if (unlikely(bio =3D=3D NULL))
>> - =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 goto fail_put_bio;
>> + =A0 =A0 =A0 =A0 =A0 =A0 if (operation =3D=3D WRITE_FLUSH) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 bio =3D bio_alloc(GFP_KERNEL, =
0);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (unlikely(bio =3D=3D NULL))
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 goto fail_put_=
bio;
>>
>> - =A0 =A0 =A0 =A0 =A0 =A0 biolist[nbio++] =3D bio;
>> - =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_bdev =A0 =A0=3D preq.bdev;
>> - =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_private =3D pending_req;
>> - =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_end_io =A0=3D end_block_io_op;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 biolist[nbio++] =3D bio;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_bdev =A0 =A0=3D preq.b=
dev;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_private =3D pending_re=
q;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 bio->bi_end_io =A0=3D end_bloc=
k_io_op;
>> + =A0 =A0 =A0 =A0 =A0 =A0 } else if (operation =3D=3D REQ_DISCARD) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 int err =3D 0;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 int status =3D BLKIF_RSP_OKAY;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct block_device *bdev =3D =
blkif->vbd.bdev;
>> +
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 preq.nr_sects =3D req->u.trim.=
nr_sectors;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (blkif->vbd.type & VDISK_PH=
Y_BACKEND)
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* just forwar=
d the trim request */
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 err =3D blkdev=
_issue_discard(bdev,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 preq.sector_number,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 preq.nr_sects,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 GFP_KERNEL, 0);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 else if (blkif->vbd.type & VDI=
SK_FILE_BACKEND) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* punch a hol=
e in the backing file */
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct loop_de=
vice *lo =3D
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 bdev->bd_disk->private_data;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct file *f=
ile =3D lo->lo_backing_file;
>> +
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (file->f_op=
->fallocate)
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 err =3D file->f_op->fallocate(file,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 FALLOC_FL_KEEP_SIZE |
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 FALLOC_FL_PUNCH_HOLE,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 preq.sector_number << 9,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 preq.nr_sects << 9);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 else
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 err =3D -EOPNOTSUPP;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 } else
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 status =3D BLK=
IF_RSP_EOPNOTSUPP;
>> +
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (err =3D=3D -EOPNOTSUPP) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 DPRINTK("blkba=
ck: discard op failed, "
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 "not supported\n");
>
> Use pr_debug like the rest of the file does.
gonna fix
>
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 status =3D BLK=
IF_RSP_EOPNOTSUPP;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 } else if (err)
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 status =3D BLK=
IF_RSP_ERROR;
>> +
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (status =3D=3D BLKIF_RSP_OK=
AY)
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 blkif->st_tr_s=
ect +=3D preq.nr_sects;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 make_response(blkif, req->id, =
req->operation, status);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 xen_blkif_put(blkif);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 free_req(pending_req);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 return 0;
>> + =A0 =A0 =A0 =A0 =A0 =A0 }
>
> All of this should really be moved to its own function.
not quite clear about this, do you mean we should make sth like
dispatch_trim_block_io only for OP_TRIM?
I added the trim handling stuff to dispatch_rw_block_io because it
also handles flush stuff.
>
>> =A0 =A0 =A0 }
>>
>> =A0 =A0 =A0 /*
>> diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkb=
ack/common.h
>> index 9e40b28..1fef727 100644
>> --- a/drivers/block/xen-blkback/common.h
>> +++ b/drivers/block/xen-blkback/common.h
>> @@ -159,8 +159,10 @@ struct xen_blkif {
>> =A0 =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_wr_req;
>> =A0 =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_oo_req;
>> =A0 =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_f_req;
>> + =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_tr_req;
>> =A0 =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_rd_sect;
>> =A0 =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_wr_sect;
>> + =A0 =A0 int =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 st_tr_sect;
>>
>> =A0 =A0 =A0 wait_queue_head_t =A0 =A0 =A0 waiting_to_free;
>>
>> @@ -182,7 +184,7 @@ struct xen_blkif {
>>
>> =A0struct phys_req {
>> =A0 =A0 =A0 unsigned short =A0 =A0 =A0 =A0 =A0dev;
>> - =A0 =A0 unsigned short =A0 =A0 =A0 =A0 =A0nr_sects;
>> + =A0 =A0 blkif_sector_t =A0 =A0 =A0 =A0 =A0nr_sects;
>> =A0 =A0 =A0 struct block_device =A0 =A0 *bdev;
>> =A0 =A0 =A0 blkif_sector_t =A0 =A0 =A0 =A0 =A0sector_number;
>> =A0};
>> diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkb=
ack/xenbus.c
>> index 3f129b4..05ea8e0 100644
>> --- a/drivers/block/xen-blkback/xenbus.c
>> +++ b/drivers/block/xen-blkback/xenbus.c
>> @@ -272,16 +272,20 @@ VBD_SHOW(oo_req, =A0"%d\n", be->blkif->st_oo_req);
>> =A0VBD_SHOW(rd_req, =A0"%d\n", be->blkif->st_rd_req);
>> =A0VBD_SHOW(wr_req, =A0"%d\n", be->blkif->st_wr_req);
>> =A0VBD_SHOW(f_req, =A0"%d\n", be->blkif->st_f_req);
>> +VBD_SHOW(tr_req, "%d\n", be->blkif->st_tr_req);
>> =A0VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect);
>> =A0VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect);
>> +VBD_SHOW(tr_sect, "%d\n", be->blkif->st_tr_sect);
>>
>> =A0static struct attribute *xen_vbdstat_attrs[] =3D {
>> =A0 =A0 =A0 &dev_attr_oo_req.attr,
>> =A0 =A0 =A0 &dev_attr_rd_req.attr,
>> =A0 =A0 =A0 &dev_attr_wr_req.attr,
>> =A0 =A0 =A0 &dev_attr_f_req.attr,
>> + =A0 =A0 &dev_attr_tr_req.attr,
>> =A0 =A0 =A0 &dev_attr_rd_sect.attr,
>> =A0 =A0 =A0 &dev_attr_wr_sect.attr,
>> + =A0 =A0 &dev_attr_tr_sect.attr,
>> =A0 =A0 =A0 NULL
>> =A0};
>>
>> @@ -419,6 +423,59 @@ int xen_blkbk_flush_diskcache(struct xenbus_transac=
tion xbt,
>> =A0 =A0 =A0 return err;
>> =A0}
>>
>> +int xen_blkbk_trim(struct xenbus_transaction xbt, struct backend_info *=
be)
>> +{
>> + =A0 =A0 struct xenbus_device *dev =3D be->dev;
>> + =A0 =A0 struct xen_vbd *vbd =3D &be->blkif->vbd;
>> + =A0 =A0 char *type;
>> + =A0 =A0 int err;
>> + =A0 =A0 int state =3D 0;
>> +
>> + =A0 =A0 type =3D xenbus_read(XBT_NIL, dev->nodename, "type", NULL);
>> + =A0 =A0 if (!IS_ERR(type)) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 if (strcmp(type, "file") =3D=3D 0)
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 state =3D 1;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vbd->type |=3D VDISK_FILE_BACK=
END;
>> + =A0 =A0 =A0 =A0 =A0 =A0 if (strcmp(type, "phy") =3D=3D 0) {
>
> Use 'strncmp' please.
gonna fix
>
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct block_device *bdev =3D =
be->blkif->vbd.bdev;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 struct request_queue *q =3D bd=
ev_get_queue(bdev);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (blk_queue_discard(q)) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 err =3D xenbus=
_printf(xbt, dev->nodename,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 "discard_granularity", "%u",
>
> Hm, most of the items written to the Xenbus use '-', not '_'.
> Any particular reason for using '_'?
they are taken from struct queue_limits so I used the underscore, no
problem to change them to '-'
>
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 q->limits.discard_granularity);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (err) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 xenbus_dev_fatal(dev, err,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 "writing discard_granularity");
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 goto kfree;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 }
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 err =3D xenbus=
_printf(xbt, dev->nodename,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 "discard_alignment", "%u",
>
> Ditto here.
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 q->limits.discard_alignment);
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (err) {
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 xenbus_dev_fatal(dev, err,
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 "writing discard_alignment");
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 goto kfree;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 }
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 state =3D 1;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vbd->type |=3D=
 VDISK_PHY_BACKEND;
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 }
>> + =A0 =A0 =A0 =A0 =A0 =A0 }
>> + =A0 =A0 } else {
>> + =A0 =A0 =A0 =A0 =A0 =A0 err =3D PTR_ERR(type);
>> + =A0 =A0 =A0 =A0 =A0 =A0 xenbus_dev_fatal(dev, err, "reading type");
>> + =A0 =A0 =A0 =A0 =A0 =A0 goto out;
>> + =A0 =A0 }
>> +
>> + =A0 =A0 err =3D xenbus_printf(xbt, dev->nodename, "feature-trim",
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 "%d", state);
>> + =A0 =A0 if (err)
>> + =A0 =A0 =A0 =A0 =A0 =A0 xenbus_dev_fatal(dev, err, "writing feature-tr=
im");
>> +kfree:
>> + =A0 =A0 kfree(type);
>> +out:
>> + =A0 =A0 return err;
>> +}
>> +
>> =A0/*
>> =A0 * Entry point to this code when a new device is created. =A0Allocate=
 the basic
>> =A0 * structures, and watch the store waiting for the hotplug scripts to=
 tell us
>> @@ -650,6 +707,10 @@ again:
>> =A0 =A0 =A0 if (err)
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 goto abort;
>>
>> + =A0 =A0 err =3D xen_blkbk_trim(xbt, be);
>> + =A0 =A0 if (err)
>> + =A0 =A0 =A0 =A0 =A0 =A0 goto abort;
>> +
>> =A0 =A0 =A0 err =3D xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
>> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 (unsigned long long)=
vbd_sz(&be->blkif->vbd));
>> =A0 =A0 =A0 if (err) {
>> --
>> 1.7.6
>>
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xensource.com
>> http://lists.xensource.com/xen-devel
>