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nexedi
linux
Commits
b8d8bdfe
Commit
b8d8bdfe
authored
Oct 20, 2011
by
Jens Axboe
Browse files
Options
Browse Files
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Plain Diff
Merge branch 'stable/for-jens-3.2' of
git://oss.oracle.com/git/kwilk/xen
into for-3.2/drivers
parents
4c823cc3
6927d920
Changes
5
Show whitespace changes
Inline
Side-by-side
Showing
5 changed files
with
403 additions
and
66 deletions
+403
-66
drivers/block/xen-blkback/blkback.c
drivers/block/xen-blkback/blkback.c
+109
-21
drivers/block/xen-blkback/common.h
drivers/block/xen-blkback/common.h
+82
-18
drivers/block/xen-blkback/xenbus.c
drivers/block/xen-blkback/xenbus.c
+78
-2
drivers/block/xen-blkfront.c
drivers/block/xen-blkfront.c
+98
-25
include/xen/interface/io/blkif.h
include/xen/interface/io/blkif.h
+36
-0
No files found.
drivers/block/xen-blkback/blkback.c
View file @
b8d8bdfe
...
@@ -39,6 +39,9 @@
...
@@ -39,6 +39,9 @@
#include <linux/list.h>
#include <linux/list.h>
#include <linux/delay.h>
#include <linux/delay.h>
#include <linux/freezer.h>
#include <linux/freezer.h>
#include <linux/loop.h>
#include <linux/falloc.h>
#include <linux/fs.h>
#include <xen/events.h>
#include <xen/events.h>
#include <xen/page.h>
#include <xen/page.h>
...
@@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
...
@@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
static
void
print_stats
(
struct
xen_blkif
*
blkif
)
static
void
print_stats
(
struct
xen_blkif
*
blkif
)
{
{
pr_info
(
"xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d
\n
"
,
pr_info
(
"xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d"
" | ds %4d
\n
"
,
current
->
comm
,
blkif
->
st_oo_req
,
current
->
comm
,
blkif
->
st_oo_req
,
blkif
->
st_rd_req
,
blkif
->
st_wr_req
,
blkif
->
st_f_req
);
blkif
->
st_rd_req
,
blkif
->
st_wr_req
,
blkif
->
st_f_req
,
blkif
->
st_ds_req
);
blkif
->
st_print
=
jiffies
+
msecs_to_jiffies
(
10
*
1000
);
blkif
->
st_print
=
jiffies
+
msecs_to_jiffies
(
10
*
1000
);
blkif
->
st_rd_req
=
0
;
blkif
->
st_rd_req
=
0
;
blkif
->
st_wr_req
=
0
;
blkif
->
st_wr_req
=
0
;
blkif
->
st_oo_req
=
0
;
blkif
->
st_oo_req
=
0
;
blkif
->
st_ds_req
=
0
;
}
}
int
xen_blkif_schedule
(
void
*
arg
)
int
xen_blkif_schedule
(
void
*
arg
)
...
@@ -410,6 +416,59 @@ static int xen_blkbk_map(struct blkif_request *req,
...
@@ -410,6 +416,59 @@ static int xen_blkbk_map(struct blkif_request *req,
return
ret
;
return
ret
;
}
}
static
void
xen_blk_discard
(
struct
xen_blkif
*
blkif
,
struct
blkif_request
*
req
)
{
int
err
=
0
;
int
status
=
BLKIF_RSP_OKAY
;
struct
block_device
*
bdev
=
blkif
->
vbd
.
bdev
;
if
(
blkif
->
blk_backend_type
==
BLKIF_BACKEND_PHY
)
/* just forward the discard request */
err
=
blkdev_issue_discard
(
bdev
,
req
->
u
.
discard
.
sector_number
,
req
->
u
.
discard
.
nr_sectors
,
GFP_KERNEL
,
0
);
else
if
(
blkif
->
blk_backend_type
==
BLKIF_BACKEND_FILE
)
{
/* punch a hole in the backing file */
struct
loop_device
*
lo
=
bdev
->
bd_disk
->
private_data
;
struct
file
*
file
=
lo
->
lo_backing_file
;
if
(
file
->
f_op
->
fallocate
)
err
=
file
->
f_op
->
fallocate
(
file
,
FALLOC_FL_KEEP_SIZE
|
FALLOC_FL_PUNCH_HOLE
,
req
->
u
.
discard
.
sector_number
<<
9
,
req
->
u
.
discard
.
nr_sectors
<<
9
);
else
err
=
-
EOPNOTSUPP
;
}
else
err
=
-
EOPNOTSUPP
;
if
(
err
==
-
EOPNOTSUPP
)
{
pr_debug
(
DRV_PFX
"discard op failed, not supported
\n
"
);
status
=
BLKIF_RSP_EOPNOTSUPP
;
}
else
if
(
err
)
status
=
BLKIF_RSP_ERROR
;
make_response
(
blkif
,
req
->
id
,
req
->
operation
,
status
);
}
static
void
xen_blk_drain_io
(
struct
xen_blkif
*
blkif
)
{
atomic_set
(
&
blkif
->
drain
,
1
);
do
{
/* The initial value is one, and one refcnt taken at the
* start of the xen_blkif_schedule thread. */
if
(
atomic_read
(
&
blkif
->
refcnt
)
<=
2
)
break
;
wait_for_completion_interruptible_timeout
(
&
blkif
->
drain_complete
,
HZ
);
if
(
!
atomic_read
(
&
blkif
->
drain
))
break
;
}
while
(
!
kthread_should_stop
());
atomic_set
(
&
blkif
->
drain
,
0
);
}
/*
/*
* Completion callback on the bio's. Called as bh->b_end_io()
* Completion callback on the bio's. Called as bh->b_end_io()
*/
*/
...
@@ -422,6 +481,11 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
...
@@ -422,6 +481,11 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
pr_debug
(
DRV_PFX
"flush diskcache op failed, not supported
\n
"
);
pr_debug
(
DRV_PFX
"flush diskcache op failed, not supported
\n
"
);
xen_blkbk_flush_diskcache
(
XBT_NIL
,
pending_req
->
blkif
->
be
,
0
);
xen_blkbk_flush_diskcache
(
XBT_NIL
,
pending_req
->
blkif
->
be
,
0
);
pending_req
->
status
=
BLKIF_RSP_EOPNOTSUPP
;
pending_req
->
status
=
BLKIF_RSP_EOPNOTSUPP
;
}
else
if
((
pending_req
->
operation
==
BLKIF_OP_WRITE_BARRIER
)
&&
(
error
==
-
EOPNOTSUPP
))
{
pr_debug
(
DRV_PFX
"write barrier op failed, not supported
\n
"
);
xen_blkbk_barrier
(
XBT_NIL
,
pending_req
->
blkif
->
be
,
0
);
pending_req
->
status
=
BLKIF_RSP_EOPNOTSUPP
;
}
else
if
(
error
)
{
}
else
if
(
error
)
{
pr_debug
(
DRV_PFX
"Buffer not up-to-date at end of operation,"
pr_debug
(
DRV_PFX
"Buffer not up-to-date at end of operation,"
" error=%d
\n
"
,
error
);
" error=%d
\n
"
,
error
);
...
@@ -438,6 +502,10 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
...
@@ -438,6 +502,10 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
make_response
(
pending_req
->
blkif
,
pending_req
->
id
,
make_response
(
pending_req
->
blkif
,
pending_req
->
id
,
pending_req
->
operation
,
pending_req
->
status
);
pending_req
->
operation
,
pending_req
->
status
);
xen_blkif_put
(
pending_req
->
blkif
);
xen_blkif_put
(
pending_req
->
blkif
);
if
(
atomic_read
(
&
pending_req
->
blkif
->
refcnt
)
<=
2
)
{
if
(
atomic_read
(
&
pending_req
->
blkif
->
drain
))
complete
(
&
pending_req
->
blkif
->
drain_complete
);
}
free_req
(
pending_req
);
free_req
(
pending_req
);
}
}
}
}
...
@@ -532,7 +600,6 @@ do_block_io_op(struct xen_blkif *blkif)
...
@@ -532,7 +600,6 @@ do_block_io_op(struct xen_blkif *blkif)
return
more_to_do
;
return
more_to_do
;
}
}
/*
/*
* Transmutation of the 'struct blkif_request' to a proper 'struct bio'
* Transmutation of the 'struct blkif_request' to a proper 'struct bio'
* and call the 'submit_bio' to pass it to the underlying storage.
* and call the 'submit_bio' to pass it to the underlying storage.
...
@@ -549,6 +616,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -549,6 +616,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
int
i
,
nbio
=
0
;
int
i
,
nbio
=
0
;
int
operation
;
int
operation
;
struct
blk_plug
plug
;
struct
blk_plug
plug
;
bool
drain
=
false
;
switch
(
req
->
operation
)
{
switch
(
req
->
operation
)
{
case
BLKIF_OP_READ
:
case
BLKIF_OP_READ
:
...
@@ -559,11 +627,16 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -559,11 +627,16 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
blkif
->
st_wr_req
++
;
blkif
->
st_wr_req
++
;
operation
=
WRITE_ODIRECT
;
operation
=
WRITE_ODIRECT
;
break
;
break
;
case
BLKIF_OP_WRITE_BARRIER
:
drain
=
true
;
case
BLKIF_OP_FLUSH_DISKCACHE
:
case
BLKIF_OP_FLUSH_DISKCACHE
:
blkif
->
st_f_req
++
;
blkif
->
st_f_req
++
;
operation
=
WRITE_FLUSH
;
operation
=
WRITE_FLUSH
;
break
;
break
;
case
BLKIF_OP_WRITE_BARRIER
:
case
BLKIF_OP_DISCARD
:
blkif
->
st_ds_req
++
;
operation
=
REQ_DISCARD
;
break
;
default:
default:
operation
=
0
;
/* make gcc happy */
operation
=
0
;
/* make gcc happy */
goto
fail_response
;
goto
fail_response
;
...
@@ -572,7 +645,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -572,7 +645,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
/* Check that the number of segments is sane. */
/* Check that the number of segments is sane. */
nseg
=
req
->
nr_segments
;
nseg
=
req
->
nr_segments
;
if
(
unlikely
(
nseg
==
0
&&
operation
!=
WRITE_FLUSH
)
||
if
(
unlikely
(
nseg
==
0
&&
operation
!=
WRITE_FLUSH
&&
operation
!=
REQ_DISCARD
)
||
unlikely
(
nseg
>
BLKIF_MAX_SEGMENTS_PER_REQUEST
))
{
unlikely
(
nseg
>
BLKIF_MAX_SEGMENTS_PER_REQUEST
))
{
pr_debug
(
DRV_PFX
"Bad number of segments in request (%d)
\n
"
,
pr_debug
(
DRV_PFX
"Bad number of segments in request (%d)
\n
"
,
nseg
);
nseg
);
...
@@ -621,16 +695,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -621,16 +695,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
}
}
}
}
/* Wait on all outstanding I/O's and once that has been completed
* issue the WRITE_FLUSH.
*/
if
(
drain
)
xen_blk_drain_io
(
pending_req
->
blkif
);
/*
/*
* If we have failed at this point, we need to undo the M2P override,
* If we have failed at this point, we need to undo the M2P override,
* set gnttab_set_unmap_op on all of the grant references and perform
* set gnttab_set_unmap_op on all of the grant references and perform
* the hypercall to unmap the grants - that is all done in
* the hypercall to unmap the grants - that is all done in
* xen_blkbk_unmap.
* xen_blkbk_unmap.
*/
*/
if
(
xen_blkbk_map
(
req
,
pending_req
,
seg
))
if
(
operation
!=
REQ_DISCARD
&&
xen_blkbk_map
(
req
,
pending_req
,
seg
))
goto
fail_flush
;
goto
fail_flush
;
/* This corresponding xen_blkif_put is done in __end_block_io_op */
/*
* This corresponding xen_blkif_put is done in __end_block_io_op, or
* below (in "!bio") if we are handling a BLKIF_OP_DISCARD.
*/
xen_blkif_get
(
blkif
);
xen_blkif_get
(
blkif
);
for
(
i
=
0
;
i
<
nseg
;
i
++
)
{
for
(
i
=
0
;
i
<
nseg
;
i
++
)
{
...
@@ -654,10 +737,11 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -654,10 +737,11 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
preq
.
sector_number
+=
seg
[
i
].
nsec
;
preq
.
sector_number
+=
seg
[
i
].
nsec
;
}
}
/* This will be hit if the operation was a flush. */
/* This will be hit if the operation was a flush
or discard
. */
if
(
!
bio
)
{
if
(
!
bio
)
{
BUG_ON
(
operation
!=
WRITE_FLUSH
);
BUG_ON
(
operation
!=
WRITE_FLUSH
&&
operation
!=
REQ_DISCARD
);
if
(
operation
==
WRITE_FLUSH
)
{
bio
=
bio_alloc
(
GFP_KERNEL
,
0
);
bio
=
bio_alloc
(
GFP_KERNEL
,
0
);
if
(
unlikely
(
bio
==
NULL
))
if
(
unlikely
(
bio
==
NULL
))
goto
fail_put_bio
;
goto
fail_put_bio
;
...
@@ -666,6 +750,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -666,6 +750,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
bio
->
bi_bdev
=
preq
.
bdev
;
bio
->
bi_bdev
=
preq
.
bdev
;
bio
->
bi_private
=
pending_req
;
bio
->
bi_private
=
pending_req
;
bio
->
bi_end_io
=
end_block_io_op
;
bio
->
bi_end_io
=
end_block_io_op
;
}
else
if
(
operation
==
REQ_DISCARD
)
{
xen_blk_discard
(
blkif
,
req
);
xen_blkif_put
(
blkif
);
free_req
(
pending_req
);
return
0
;
}
}
}
/*
/*
...
@@ -685,7 +775,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
...
@@ -685,7 +775,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
if
(
operation
==
READ
)
if
(
operation
==
READ
)
blkif
->
st_rd_sect
+=
preq
.
nr_sects
;
blkif
->
st_rd_sect
+=
preq
.
nr_sects
;
else
if
(
operation
==
WRITE
||
operation
==
WRITE_FLUSH
)
else
if
(
operation
&
WRITE
)
blkif
->
st_wr_sect
+=
preq
.
nr_sects
;
blkif
->
st_wr_sect
+=
preq
.
nr_sects
;
return
0
;
return
0
;
...
@@ -765,9 +855,9 @@ static int __init xen_blkif_init(void)
...
@@ -765,9 +855,9 @@ static int __init xen_blkif_init(void)
mmap_pages
=
xen_blkif_reqs
*
BLKIF_MAX_SEGMENTS_PER_REQUEST
;
mmap_pages
=
xen_blkif_reqs
*
BLKIF_MAX_SEGMENTS_PER_REQUEST
;
blkbk
->
pending_reqs
=
k
m
alloc
(
sizeof
(
blkbk
->
pending_reqs
[
0
])
*
blkbk
->
pending_reqs
=
k
z
alloc
(
sizeof
(
blkbk
->
pending_reqs
[
0
])
*
xen_blkif_reqs
,
GFP_KERNEL
);
xen_blkif_reqs
,
GFP_KERNEL
);
blkbk
->
pending_grant_handles
=
k
z
alloc
(
sizeof
(
blkbk
->
pending_grant_handles
[
0
])
*
blkbk
->
pending_grant_handles
=
k
m
alloc
(
sizeof
(
blkbk
->
pending_grant_handles
[
0
])
*
mmap_pages
,
GFP_KERNEL
);
mmap_pages
,
GFP_KERNEL
);
blkbk
->
pending_pages
=
kzalloc
(
sizeof
(
blkbk
->
pending_pages
[
0
])
*
blkbk
->
pending_pages
=
kzalloc
(
sizeof
(
blkbk
->
pending_pages
[
0
])
*
mmap_pages
,
GFP_KERNEL
);
mmap_pages
,
GFP_KERNEL
);
...
@@ -790,8 +880,6 @@ static int __init xen_blkif_init(void)
...
@@ -790,8 +880,6 @@ static int __init xen_blkif_init(void)
if
(
rc
)
if
(
rc
)
goto
failed_init
;
goto
failed_init
;
memset
(
blkbk
->
pending_reqs
,
0
,
sizeof
(
blkbk
->
pending_reqs
));
INIT_LIST_HEAD
(
&
blkbk
->
pending_free
);
INIT_LIST_HEAD
(
&
blkbk
->
pending_free
);
spin_lock_init
(
&
blkbk
->
pending_free_lock
);
spin_lock_init
(
&
blkbk
->
pending_free_lock
);
init_waitqueue_head
(
&
blkbk
->
pending_free_wq
);
init_waitqueue_head
(
&
blkbk
->
pending_free_wq
);
...
...
drivers/block/xen-blkback/common.h
View file @
b8d8bdfe
...
@@ -63,13 +63,26 @@ struct blkif_common_response {
...
@@ -63,13 +63,26 @@ struct blkif_common_response {
/* i386 protocol version */
/* i386 protocol version */
#pragma pack(push, 4)
#pragma pack(push, 4)
struct
blkif_x86_32_request_rw
{
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
struct
blkif_request_segment
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
};
struct
blkif_x86_32_request_discard
{
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
uint64_t
nr_sectors
;
};
struct
blkif_x86_32_request
{
struct
blkif_x86_32_request
{
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
nr_segments
;
/* number of segments */
uint8_t
nr_segments
;
/* number of segments */
blkif_vdev_t
handle
;
/* only for read/write requests */
blkif_vdev_t
handle
;
/* only for read/write requests */
uint64_t
id
;
/* private guest value, echoed in resp */
uint64_t
id
;
/* private guest value, echoed in resp */
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
union
{
struct
blkif_request_segment
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
struct
blkif_x86_32_request_rw
rw
;
struct
blkif_x86_32_request_discard
discard
;
}
u
;
};
};
struct
blkif_x86_32_response
{
struct
blkif_x86_32_response
{
uint64_t
id
;
/* copied from request */
uint64_t
id
;
/* copied from request */
...
@@ -79,13 +92,26 @@ struct blkif_x86_32_response {
...
@@ -79,13 +92,26 @@ struct blkif_x86_32_response {
#pragma pack(pop)
#pragma pack(pop)
/* x86_64 protocol version */
/* x86_64 protocol version */
struct
blkif_x86_64_request_rw
{
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
struct
blkif_request_segment
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
};
struct
blkif_x86_64_request_discard
{
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
uint64_t
nr_sectors
;
};
struct
blkif_x86_64_request
{
struct
blkif_x86_64_request
{
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
nr_segments
;
/* number of segments */
uint8_t
nr_segments
;
/* number of segments */
blkif_vdev_t
handle
;
/* only for read/write requests */
blkif_vdev_t
handle
;
/* only for read/write requests */
uint64_t
__attribute__
((
__aligned__
(
8
)))
id
;
uint64_t
__attribute__
((
__aligned__
(
8
)))
id
;
blkif_sector_t
sector_number
;
/* start sector idx on disk (r/w only) */
union
{
struct
blkif_request_segment
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
struct
blkif_x86_64_request_rw
rw
;
struct
blkif_x86_64_request_discard
discard
;
}
u
;
};
};
struct
blkif_x86_64_response
{
struct
blkif_x86_64_response
{
uint64_t
__attribute__
((
__aligned__
(
8
)))
id
;
uint64_t
__attribute__
((
__aligned__
(
8
)))
id
;
...
@@ -113,6 +139,11 @@ enum blkif_protocol {
...
@@ -113,6 +139,11 @@ enum blkif_protocol {
BLKIF_PROTOCOL_X86_64
=
3
,
BLKIF_PROTOCOL_X86_64
=
3
,
};
};
enum
blkif_backend_type
{
BLKIF_BACKEND_PHY
=
1
,
BLKIF_BACKEND_FILE
=
2
,
};
struct
xen_vbd
{
struct
xen_vbd
{
/* What the domain refers to this vbd as. */
/* What the domain refers to this vbd as. */
blkif_vdev_t
handle
;
blkif_vdev_t
handle
;
...
@@ -138,6 +169,7 @@ struct xen_blkif {
...
@@ -138,6 +169,7 @@ struct xen_blkif {
unsigned
int
irq
;
unsigned
int
irq
;
/* Comms information. */
/* Comms information. */
enum
blkif_protocol
blk_protocol
;
enum
blkif_protocol
blk_protocol
;
enum
blkif_backend_type
blk_backend_type
;
union
blkif_back_rings
blk_rings
;
union
blkif_back_rings
blk_rings
;
struct
vm_struct
*
blk_ring_area
;
struct
vm_struct
*
blk_ring_area
;
/* The VBD attached to this interface. */
/* The VBD attached to this interface. */
...
@@ -149,6 +181,9 @@ struct xen_blkif {
...
@@ -149,6 +181,9 @@ struct xen_blkif {
atomic_t
refcnt
;
atomic_t
refcnt
;
wait_queue_head_t
wq
;
wait_queue_head_t
wq
;
/* for barrier (drain) requests */
struct
completion
drain_complete
;
atomic_t
drain
;
/* One thread per one blkif. */
/* One thread per one blkif. */
struct
task_struct
*
xenblkd
;
struct
task_struct
*
xenblkd
;
unsigned
int
waiting_reqs
;
unsigned
int
waiting_reqs
;
...
@@ -159,6 +194,7 @@ struct xen_blkif {
...
@@ -159,6 +194,7 @@ struct xen_blkif {
int
st_wr_req
;
int
st_wr_req
;
int
st_oo_req
;
int
st_oo_req
;
int
st_f_req
;
int
st_f_req
;
int
st_ds_req
;
int
st_rd_sect
;
int
st_rd_sect
;
int
st_wr_sect
;
int
st_wr_sect
;
...
@@ -182,7 +218,7 @@ struct xen_blkif {
...
@@ -182,7 +218,7 @@ struct xen_blkif {
struct
phys_req
{
struct
phys_req
{
unsigned
short
dev
;
unsigned
short
dev
;
unsigned
shor
t
nr_sects
;
blkif_sector_
t
nr_sects
;
struct
block_device
*
bdev
;
struct
block_device
*
bdev
;
blkif_sector_t
sector_number
;
blkif_sector_t
sector_number
;
};
};
...
@@ -196,6 +232,8 @@ int xen_blkif_schedule(void *arg);
...
@@ -196,6 +232,8 @@ int xen_blkif_schedule(void *arg);
int
xen_blkbk_flush_diskcache
(
struct
xenbus_transaction
xbt
,
int
xen_blkbk_flush_diskcache
(
struct
xenbus_transaction
xbt
,
struct
backend_info
*
be
,
int
state
);
struct
backend_info
*
be
,
int
state
);
int
xen_blkbk_barrier
(
struct
xenbus_transaction
xbt
,
struct
backend_info
*
be
,
int
state
);
struct
xenbus_device
*
xen_blkbk_xenbus
(
struct
backend_info
*
be
);
struct
xenbus_device
*
xen_blkbk_xenbus
(
struct
backend_info
*
be
);
static
inline
void
blkif_get_x86_32_req
(
struct
blkif_request
*
dst
,
static
inline
void
blkif_get_x86_32_req
(
struct
blkif_request
*
dst
,
...
@@ -206,12 +244,25 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst,
...
@@ -206,12 +244,25 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst,
dst
->
nr_segments
=
src
->
nr_segments
;
dst
->
nr_segments
=
src
->
nr_segments
;
dst
->
handle
=
src
->
handle
;
dst
->
handle
=
src
->
handle
;
dst
->
id
=
src
->
id
;
dst
->
id
=
src
->
id
;
dst
->
u
.
rw
.
sector_number
=
src
->
sector_number
;
switch
(
src
->
operation
)
{
case
BLKIF_OP_READ
:
case
BLKIF_OP_WRITE
:
case
BLKIF_OP_WRITE_BARRIER
:
case
BLKIF_OP_FLUSH_DISKCACHE
:
dst
->
u
.
rw
.
sector_number
=
src
->
u
.
rw
.
sector_number
;
barrier
();
barrier
();
if
(
n
>
dst
->
nr_segments
)
if
(
n
>
dst
->
nr_segments
)
n
=
dst
->
nr_segments
;
n
=
dst
->
nr_segments
;
for
(
i
=
0
;
i
<
n
;
i
++
)
for
(
i
=
0
;
i
<
n
;
i
++
)
dst
->
u
.
rw
.
seg
[
i
]
=
src
->
seg
[
i
];
dst
->
u
.
rw
.
seg
[
i
]
=
src
->
u
.
rw
.
seg
[
i
];
break
;
case
BLKIF_OP_DISCARD
:
dst
->
u
.
discard
.
sector_number
=
src
->
u
.
discard
.
sector_number
;
dst
->
u
.
discard
.
nr_sectors
=
src
->
u
.
discard
.
nr_sectors
;
break
;
default:
break
;
}
}
}
static
inline
void
blkif_get_x86_64_req
(
struct
blkif_request
*
dst
,
static
inline
void
blkif_get_x86_64_req
(
struct
blkif_request
*
dst
,
...
@@ -222,12 +273,25 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst,
...
@@ -222,12 +273,25 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst,
dst
->
nr_segments
=
src
->
nr_segments
;
dst
->
nr_segments
=
src
->
nr_segments
;
dst
->
handle
=
src
->
handle
;
dst
->
handle
=
src
->
handle
;
dst
->
id
=
src
->
id
;
dst
->
id
=
src
->
id
;
dst
->
u
.
rw
.
sector_number
=
src
->
sector_number
;
switch
(
src
->
operation
)
{
case
BLKIF_OP_READ
:
case
BLKIF_OP_WRITE
:
case
BLKIF_OP_WRITE_BARRIER
:
case
BLKIF_OP_FLUSH_DISKCACHE
:
dst
->
u
.
rw
.
sector_number
=
src
->
u
.
rw
.
sector_number
;
barrier
();
barrier
();
if
(
n
>
dst
->
nr_segments
)
if
(
n
>
dst
->
nr_segments
)
n
=
dst
->
nr_segments
;
n
=
dst
->
nr_segments
;
for
(
i
=
0
;
i
<
n
;
i
++
)
for
(
i
=
0
;
i
<
n
;
i
++
)
dst
->
u
.
rw
.
seg
[
i
]
=
src
->
seg
[
i
];
dst
->
u
.
rw
.
seg
[
i
]
=
src
->
u
.
rw
.
seg
[
i
];
break
;
case
BLKIF_OP_DISCARD
:
dst
->
u
.
discard
.
sector_number
=
src
->
u
.
discard
.
sector_number
;
dst
->
u
.
discard
.
nr_sectors
=
src
->
u
.
discard
.
nr_sectors
;
break
;
default:
break
;
}
}
}
#endif
/* __XEN_BLKIF__BACKEND__COMMON_H__ */
#endif
/* __XEN_BLKIF__BACKEND__COMMON_H__ */
drivers/block/xen-blkback/xenbus.c
View file @
b8d8bdfe
...
@@ -114,6 +114,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
...
@@ -114,6 +114,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
spin_lock_init
(
&
blkif
->
blk_ring_lock
);
spin_lock_init
(
&
blkif
->
blk_ring_lock
);
atomic_set
(
&
blkif
->
refcnt
,
1
);
atomic_set
(
&
blkif
->
refcnt
,
1
);
init_waitqueue_head
(
&
blkif
->
wq
);
init_waitqueue_head
(
&
blkif
->
wq
);
init_completion
(
&
blkif
->
drain_complete
);
atomic_set
(
&
blkif
->
drain
,
0
);
blkif
->
st_print
=
jiffies
;
blkif
->
st_print
=
jiffies
;
init_waitqueue_head
(
&
blkif
->
waiting_to_free
);
init_waitqueue_head
(
&
blkif
->
waiting_to_free
);
...
@@ -272,6 +274,7 @@ VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req);
...
@@ -272,6 +274,7 @@ VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req);
VBD_SHOW
(
rd_req
,
"%d
\n
"
,
be
->
blkif
->
st_rd_req
);
VBD_SHOW
(
rd_req
,
"%d
\n
"
,
be
->
blkif
->
st_rd_req
);
VBD_SHOW
(
wr_req
,
"%d
\n
"
,
be
->
blkif
->
st_wr_req
);
VBD_SHOW
(
wr_req
,
"%d
\n
"
,
be
->
blkif
->
st_wr_req
);
VBD_SHOW
(
f_req
,
"%d
\n
"
,
be
->
blkif
->
st_f_req
);
VBD_SHOW
(
f_req
,
"%d
\n
"
,
be
->
blkif
->
st_f_req
);
VBD_SHOW
(
ds_req
,
"%d
\n
"
,
be
->
blkif
->
st_ds_req
);
VBD_SHOW
(
rd_sect
,
"%d
\n
"
,
be
->
blkif
->
st_rd_sect
);
VBD_SHOW
(
rd_sect
,
"%d
\n
"
,
be
->
blkif
->
st_rd_sect
);
VBD_SHOW
(
wr_sect
,
"%d
\n
"
,
be
->
blkif
->
st_wr_sect
);
VBD_SHOW
(
wr_sect
,
"%d
\n
"
,
be
->
blkif
->
st_wr_sect
);
...
@@ -280,6 +283,7 @@ static struct attribute *xen_vbdstat_attrs[] = {
...
@@ -280,6 +283,7 @@ static struct attribute *xen_vbdstat_attrs[] = {
&
dev_attr_rd_req
.
attr
,
&
dev_attr_rd_req
.
attr
,
&
dev_attr_wr_req
.
attr
,
&
dev_attr_wr_req
.
attr
,
&
dev_attr_f_req
.
attr
,
&
dev_attr_f_req
.
attr
,
&
dev_attr_ds_req
.
attr
,
&
dev_attr_rd_sect
.
attr
,
&
dev_attr_rd_sect
.
attr
,
&
dev_attr_wr_sect
.
attr
,
&
dev_attr_wr_sect
.
attr
,
NULL
NULL
...
@@ -419,6 +423,73 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
...
@@ -419,6 +423,73 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
return
err
;
return
err
;
}
}
int
xen_blkbk_discard
(
struct
xenbus_transaction
xbt
,
struct
backend_info
*
be
)
{
struct
xenbus_device
*
dev
=
be
->
dev
;
struct
xen_blkif
*
blkif
=
be
->
blkif
;
char
*
type
;
int
err
;
int
state
=
0
;
type
=
xenbus_read
(
XBT_NIL
,
dev
->
nodename
,
"type"
,
NULL
);
if
(
!
IS_ERR
(
type
))
{
if
(
strncmp
(
type
,
"file"
,
4
)
==
0
)
{
state
=
1
;
blkif
->
blk_backend_type
=
BLKIF_BACKEND_FILE
;
}
if
(
strncmp
(
type
,
"phy"
,
3
)
==
0
)
{
struct
block_device
*
bdev
=
be
->
blkif
->
vbd
.
bdev
;
struct
request_queue
*
q
=
bdev_get_queue
(
bdev
);
if
(
blk_queue_discard
(
q
))
{
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"discard-granularity"
,
"%u"
,
q
->
limits
.
discard_granularity
);
if
(
err
)
{
xenbus_dev_fatal
(
dev
,
err
,
"writing discard-granularity"
);
goto
kfree
;
}
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"discard-alignment"
,
"%u"
,
q
->
limits
.
discard_alignment
);
if
(
err
)
{
xenbus_dev_fatal
(
dev
,
err
,
"writing discard-alignment"
);
goto
kfree
;
}
state
=
1
;
blkif
->
blk_backend_type
=
BLKIF_BACKEND_PHY
;
}
}
}
else
{
err
=
PTR_ERR
(
type
);
xenbus_dev_fatal
(
dev
,
err
,
"reading type"
);
goto
out
;
}
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"feature-discard"
,
"%d"
,
state
);
if
(
err
)
xenbus_dev_fatal
(
dev
,
err
,
"writing feature-discard"
);
kfree:
kfree
(
type
);
out:
return
err
;
}
int
xen_blkbk_barrier
(
struct
xenbus_transaction
xbt
,
struct
backend_info
*
be
,
int
state
)
{
struct
xenbus_device
*
dev
=
be
->
dev
;
int
err
;
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"feature-barrier"
,
"%d"
,
state
);
if
(
err
)
xenbus_dev_fatal
(
dev
,
err
,
"writing feature-barrier"
);
return
err
;
}
/*
/*
* Entry point to this code when a new device is created. Allocate the basic
* Entry point to this code when a new device is created. Allocate the basic
* structures, and watch the store waiting for the hotplug scripts to tell us
* structures, and watch the store waiting for the hotplug scripts to tell us
...
@@ -590,7 +661,7 @@ static void frontend_changed(struct xenbus_device *dev,
...
@@ -590,7 +661,7 @@ static void frontend_changed(struct xenbus_device *dev,
/*
/*
* Enforce precondition before potential leak point.
* Enforce precondition before potential leak point.
* blkif_disconnect() is idempotent.
*
xen_
blkif_disconnect() is idempotent.
*/
*/
xen_blkif_disconnect
(
be
->
blkif
);
xen_blkif_disconnect
(
be
->
blkif
);
...
@@ -611,7 +682,7 @@ static void frontend_changed(struct xenbus_device *dev,
...
@@ -611,7 +682,7 @@ static void frontend_changed(struct xenbus_device *dev,
break
;
break
;
/* fall through if not online */
/* fall through if not online */
case
XenbusStateUnknown
:
case
XenbusStateUnknown
:
/* implies
blkif_disconnect() via blkbac
k_remove() */
/* implies
xen_blkif_disconnect() via xen_blkb
k_remove() */
device_unregister
(
&
dev
->
dev
);
device_unregister
(
&
dev
->
dev
);
break
;
break
;
...
@@ -650,6 +721,11 @@ static void connect(struct backend_info *be)
...
@@ -650,6 +721,11 @@ static void connect(struct backend_info *be)
if
(
err
)
if
(
err
)
goto
abort
;
goto
abort
;
err
=
xen_blkbk_discard
(
xbt
,
be
);
/* If we can't advertise it is OK. */
err
=
xen_blkbk_barrier
(
xbt
,
be
,
be
->
blkif
->
vbd
.
flush_support
);
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"sectors"
,
"%llu"
,
err
=
xenbus_printf
(
xbt
,
dev
->
nodename
,
"sectors"
,
"%llu"
,
(
unsigned
long
long
)
vbd_sz
(
&
be
->
blkif
->
vbd
));
(
unsigned
long
long
)
vbd_sz
(
&
be
->
blkif
->
vbd
));
if
(
err
)
{
if
(
err
)
{
...
...
drivers/block/xen-blkfront.c
View file @
b8d8bdfe
...
@@ -98,6 +98,9 @@ struct blkfront_info
...
@@ -98,6 +98,9 @@ struct blkfront_info
unsigned
long
shadow_free
;
unsigned
long
shadow_free
;
unsigned
int
feature_flush
;
unsigned
int
feature_flush
;
unsigned
int
flush_op
;
unsigned
int
flush_op
;
unsigned
int
feature_discard
;
unsigned
int
discard_granularity
;
unsigned
int
discard_alignment
;
int
is_ready
;
int
is_ready
;
};
};
...
@@ -302,6 +305,12 @@ static int blkif_queue_request(struct request *req)
...
@@ -302,6 +305,12 @@ static int blkif_queue_request(struct request *req)
ring_req
->
operation
=
info
->
flush_op
;
ring_req
->
operation
=
info
->
flush_op
;
}
}
if
(
unlikely
(
req
->
cmd_flags
&
REQ_DISCARD
))
{
/* id, sector_number and handle are set above. */
ring_req
->
operation
=
BLKIF_OP_DISCARD
;
ring_req
->
nr_segments
=
0
;
ring_req
->
u
.
discard
.
nr_sectors
=
blk_rq_sectors
(
req
);
}
else
{
ring_req
->
nr_segments
=
blk_rq_map_sg
(
req
->
q
,
req
,
info
->
sg
);
ring_req
->
nr_segments
=
blk_rq_map_sg
(
req
->
q
,
req
,
info
->
sg
);
BUG_ON
(
ring_req
->
nr_segments
>
BLKIF_MAX_SEGMENTS_PER_REQUEST
);
BUG_ON
(
ring_req
->
nr_segments
>
BLKIF_MAX_SEGMENTS_PER_REQUEST
);
...
@@ -317,7 +326,7 @@ static int blkif_queue_request(struct request *req)
...
@@ -317,7 +326,7 @@ static int blkif_queue_request(struct request *req)
ref
,
ref
,
info
->
xbdev
->
otherend_id
,
info
->
xbdev
->
otherend_id
,
buffer_mfn
,
buffer_mfn
,
rq_data_dir
(
req
)
);
rq_data_dir
(
req
)
);
info
->
shadow
[
id
].
frame
[
i
]
=
mfn_to_pfn
(
buffer_mfn
);
info
->
shadow
[
id
].
frame
[
i
]
=
mfn_to_pfn
(
buffer_mfn
);
ring_req
->
u
.
rw
.
seg
[
i
]
=
ring_req
->
u
.
rw
.
seg
[
i
]
=
...
@@ -326,6 +335,7 @@ static int blkif_queue_request(struct request *req)
...
@@ -326,6 +335,7 @@ static int blkif_queue_request(struct request *req)
.
first_sect
=
fsect
,
.
first_sect
=
fsect
,
.
last_sect
=
lsect
};
.
last_sect
=
lsect
};
}
}
}
info
->
ring
.
req_prod_pvt
++
;
info
->
ring
.
req_prod_pvt
++
;
...
@@ -370,7 +380,9 @@ static void do_blkif_request(struct request_queue *rq)
...
@@ -370,7 +380,9 @@ static void do_blkif_request(struct request_queue *rq)
blk_start_request
(
req
);
blk_start_request
(
req
);
if
(
req
->
cmd_type
!=
REQ_TYPE_FS
)
{
if
((
req
->
cmd_type
!=
REQ_TYPE_FS
)
||
((
req
->
cmd_flags
&
(
REQ_FLUSH
|
REQ_FUA
))
&&
!
info
->
flush_op
))
{
__blk_end_request_all
(
req
,
-
EIO
);
__blk_end_request_all
(
req
,
-
EIO
);
continue
;
continue
;
}
}
...
@@ -399,6 +411,7 @@ static void do_blkif_request(struct request_queue *rq)
...
@@ -399,6 +411,7 @@ static void do_blkif_request(struct request_queue *rq)
static
int
xlvbd_init_blk_queue
(
struct
gendisk
*
gd
,
u16
sector_size
)
static
int
xlvbd_init_blk_queue
(
struct
gendisk
*
gd
,
u16
sector_size
)
{
{
struct
request_queue
*
rq
;
struct
request_queue
*
rq
;
struct
blkfront_info
*
info
=
gd
->
private_data
;
rq
=
blk_init_queue
(
do_blkif_request
,
&
blkif_io_lock
);
rq
=
blk_init_queue
(
do_blkif_request
,
&
blkif_io_lock
);
if
(
rq
==
NULL
)
if
(
rq
==
NULL
)
...
@@ -406,6 +419,13 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
...
@@ -406,6 +419,13 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
queue_flag_set_unlocked
(
QUEUE_FLAG_VIRT
,
rq
);
queue_flag_set_unlocked
(
QUEUE_FLAG_VIRT
,
rq
);
if
(
info
->
feature_discard
)
{
queue_flag_set_unlocked
(
QUEUE_FLAG_DISCARD
,
rq
);
blk_queue_max_discard_sectors
(
rq
,
get_capacity
(
gd
));
rq
->
limits
.
discard_granularity
=
info
->
discard_granularity
;
rq
->
limits
.
discard_alignment
=
info
->
discard_alignment
;
}
/* Hard sector size and max sectors impersonate the equiv. hardware. */
/* Hard sector size and max sectors impersonate the equiv. hardware. */
blk_queue_logical_block_size
(
rq
,
sector_size
);
blk_queue_logical_block_size
(
rq
,
sector_size
);
blk_queue_max_hw_sectors
(
rq
,
512
);
blk_queue_max_hw_sectors
(
rq
,
512
);
...
@@ -722,6 +742,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
...
@@ -722,6 +742,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
error
=
(
bret
->
status
==
BLKIF_RSP_OKAY
)
?
0
:
-
EIO
;
error
=
(
bret
->
status
==
BLKIF_RSP_OKAY
)
?
0
:
-
EIO
;
switch
(
bret
->
operation
)
{
switch
(
bret
->
operation
)
{
case
BLKIF_OP_DISCARD
:
if
(
unlikely
(
bret
->
status
==
BLKIF_RSP_EOPNOTSUPP
))
{
struct
request_queue
*
rq
=
info
->
rq
;
printk
(
KERN_WARNING
"blkfront: %s: discard op failed
\n
"
,
info
->
gd
->
disk_name
);
error
=
-
EOPNOTSUPP
;
info
->
feature_discard
=
0
;
queue_flag_clear
(
QUEUE_FLAG_DISCARD
,
rq
);
}
__blk_end_request_all
(
req
,
error
);
break
;
case
BLKIF_OP_FLUSH_DISKCACHE
:
case
BLKIF_OP_FLUSH_DISKCACHE
:
case
BLKIF_OP_WRITE_BARRIER
:
case
BLKIF_OP_WRITE_BARRIER
:
if
(
unlikely
(
bret
->
status
==
BLKIF_RSP_EOPNOTSUPP
))
{
if
(
unlikely
(
bret
->
status
==
BLKIF_RSP_EOPNOTSUPP
))
{
...
@@ -1098,6 +1129,33 @@ blkfront_closing(struct blkfront_info *info)
...
@@ -1098,6 +1129,33 @@ blkfront_closing(struct blkfront_info *info)
bdput
(
bdev
);
bdput
(
bdev
);
}
}
static
void
blkfront_setup_discard
(
struct
blkfront_info
*
info
)
{
int
err
;
char
*
type
;
unsigned
int
discard_granularity
;
unsigned
int
discard_alignment
;
type
=
xenbus_read
(
XBT_NIL
,
info
->
xbdev
->
otherend
,
"type"
,
NULL
);
if
(
IS_ERR
(
type
))
return
;
if
(
strncmp
(
type
,
"phy"
,
3
)
==
0
)
{
err
=
xenbus_gather
(
XBT_NIL
,
info
->
xbdev
->
otherend
,
"discard-granularity"
,
"%u"
,
&
discard_granularity
,
"discard-alignment"
,
"%u"
,
&
discard_alignment
,
NULL
);
if
(
!
err
)
{
info
->
feature_discard
=
1
;
info
->
discard_granularity
=
discard_granularity
;
info
->
discard_alignment
=
discard_alignment
;
}
}
else
if
(
strncmp
(
type
,
"file"
,
4
)
==
0
)
info
->
feature_discard
=
1
;
kfree
(
type
);
}
/*
/*
* Invoked when the backend is finally 'ready' (and has told produced
* Invoked when the backend is finally 'ready' (and has told produced
* the details about the physical device - #sectors, size, etc).
* the details about the physical device - #sectors, size, etc).
...
@@ -1108,7 +1166,7 @@ static void blkfront_connect(struct blkfront_info *info)
...
@@ -1108,7 +1166,7 @@ static void blkfront_connect(struct blkfront_info *info)
unsigned
long
sector_size
;
unsigned
long
sector_size
;
unsigned
int
binfo
;
unsigned
int
binfo
;
int
err
;
int
err
;
int
barrier
,
flush
;
int
barrier
,
flush
,
discard
;
switch
(
info
->
connected
)
{
switch
(
info
->
connected
)
{
case
BLKIF_STATE_CONNECTED
:
case
BLKIF_STATE_CONNECTED
:
...
@@ -1179,6 +1237,13 @@ static void blkfront_connect(struct blkfront_info *info)
...
@@ -1179,6 +1237,13 @@ static void blkfront_connect(struct blkfront_info *info)
info
->
flush_op
=
BLKIF_OP_FLUSH_DISKCACHE
;
info
->
flush_op
=
BLKIF_OP_FLUSH_DISKCACHE
;
}
}
err
=
xenbus_gather
(
XBT_NIL
,
info
->
xbdev
->
otherend
,
"feature-discard"
,
"%d"
,
&
discard
,
NULL
);
if
(
!
err
&&
discard
)
blkfront_setup_discard
(
info
);
err
=
xlvbd_alloc_gendisk
(
sectors
,
info
,
binfo
,
sector_size
);
err
=
xlvbd_alloc_gendisk
(
sectors
,
info
,
binfo
,
sector_size
);
if
(
err
)
{
if
(
err
)
{
xenbus_dev_fatal
(
info
->
xbdev
,
err
,
"xlvbd_add at %s"
,
xenbus_dev_fatal
(
info
->
xbdev
,
err
,
"xlvbd_add at %s"
,
...
@@ -1385,6 +1450,8 @@ static struct xenbus_driver blkfront = {
...
@@ -1385,6 +1450,8 @@ static struct xenbus_driver blkfront = {
static
int
__init
xlblk_init
(
void
)
static
int
__init
xlblk_init
(
void
)
{
{
int
ret
;
if
(
!
xen_domain
())
if
(
!
xen_domain
())
return
-
ENODEV
;
return
-
ENODEV
;
...
@@ -1394,7 +1461,13 @@ static int __init xlblk_init(void)
...
@@ -1394,7 +1461,13 @@ static int __init xlblk_init(void)
return
-
ENODEV
;
return
-
ENODEV
;
}
}
return
xenbus_register_frontend
(
&
blkfront
);
ret
=
xenbus_register_frontend
(
&
blkfront
);
if
(
ret
)
{
unregister_blkdev
(
XENVBD_MAJOR
,
DEV_NAME
);
return
ret
;
}
return
0
;
}
}
module_init
(
xlblk_init
);
module_init
(
xlblk_init
);
...
...
include/xen/interface/io/blkif.h
View file @
b8d8bdfe
...
@@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t;
...
@@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t;
* "feature-flush-cache" node!
* "feature-flush-cache" node!
*/
*/
#define BLKIF_OP_FLUSH_DISKCACHE 3
#define BLKIF_OP_FLUSH_DISKCACHE 3
/*
* Recognised only if "feature-discard" is present in backend xenbus info.
* The "feature-discard" node contains a boolean indicating whether trim
* (ATA) or unmap (SCSI) - conviently called discard requests are likely
* to succeed or fail. Either way, a discard request
* may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
* the underlying block-device hardware. The boolean simply indicates whether
* or not it is worthwhile for the frontend to attempt discard requests.
* If a backend does not recognise BLKIF_OP_DISCARD, it should *not*
* create the "feature-discard" node!
*
* Discard operation is a request for the underlying block device to mark
* extents to be erased. However, discard does not guarantee that the blocks
* will be erased from the device - it is just a hint to the device
* controller that these blocks are no longer in use. What the device
* controller does with that information is left to the controller.
* Discard operations are passed with sector_number as the
* sector index to begin discard operations at and nr_sectors as the number of
* sectors to be discarded. The specified sectors should be discarded if the
* underlying block device supports trim (ATA) or unmap (SCSI) operations,
* or a BLKIF_RSP_EOPNOTSUPP should be returned.
* More information about trim/unmap operations at:
* http://t13.org/Documents/UploadedDocuments/docs2008/
* e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc
* http://www.seagate.com/staticfiles/support/disc/manuals/
* Interface%20manuals/100293068c.pdf
*/
#define BLKIF_OP_DISCARD 5
/*
/*
* Maximum scatter/gather segments per request.
* Maximum scatter/gather segments per request.
* This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE.
* This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE.
...
@@ -74,6 +104,11 @@ struct blkif_request_rw {
...
@@ -74,6 +104,11 @@ struct blkif_request_rw {
}
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
}
seg
[
BLKIF_MAX_SEGMENTS_PER_REQUEST
];
};
};
struct
blkif_request_discard
{
blkif_sector_t
sector_number
;
uint64_t
nr_sectors
;
};
struct
blkif_request
{
struct
blkif_request
{
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
operation
;
/* BLKIF_OP_??? */
uint8_t
nr_segments
;
/* number of segments */
uint8_t
nr_segments
;
/* number of segments */
...
@@ -81,6 +116,7 @@ struct blkif_request {
...
@@ -81,6 +116,7 @@ struct blkif_request {
uint64_t
id
;
/* private guest value, echoed in resp */
uint64_t
id
;
/* private guest value, echoed in resp */
union
{
union
{
struct
blkif_request_rw
rw
;
struct
blkif_request_rw
rw
;
struct
blkif_request_discard
discard
;
}
u
;
}
u
;
};
};
...
...
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