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Kirill Smelkov
linux
Commits
bee139b3
Commit
bee139b3
authored
Apr 12, 2003
by
James Bottomley
Browse files
Options
Browse Files
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Plain Diff
Merge raven.il.steeleye.com:/home/jejb/BK/scsi-aic7xxx-2.5
into raven.il.steeleye.com:/home/jejb/BK/scsi-misc-2.5
parents
e1da10d0
f4760183
Changes
9
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Showing
9 changed files
with
329 additions
and
241 deletions
+329
-241
drivers/scsi/hosts.c
drivers/scsi/hosts.c
+1
-1
drivers/scsi/hosts.h
drivers/scsi/hosts.h
+1
-6
drivers/scsi/scsi.c
drivers/scsi/scsi.c
+4
-6
drivers/scsi/scsi.h
drivers/scsi/scsi.h
+15
-3
drivers/scsi/scsi_error.c
drivers/scsi/scsi_error.c
+5
-13
drivers/scsi/scsi_lib.c
drivers/scsi/scsi_lib.c
+229
-165
drivers/scsi/scsi_scan.c
drivers/scsi/scsi_scan.c
+71
-46
drivers/scsi/scsi_syms.c
drivers/scsi/scsi_syms.c
+2
-0
drivers/scsi/sd.c
drivers/scsi/sd.c
+1
-1
No files found.
drivers/scsi/hosts.c
View file @
bee139b3
...
...
@@ -383,6 +383,7 @@ struct Scsi_Host * scsi_register(Scsi_Host_Template *shost_tp, int xtr_bytes)
scsi_assign_lock
(
shost
,
&
shost
->
default_lock
);
INIT_LIST_HEAD
(
&
shost
->
my_devices
);
INIT_LIST_HEAD
(
&
shost
->
eh_cmd_q
);
INIT_LIST_HEAD
(
&
shost
->
starved_list
);
init_waitqueue_head
(
&
shost
->
host_wait
);
shost
->
dma_channel
=
0xff
;
...
...
@@ -619,7 +620,6 @@ void scsi_host_busy_dec_and_test(struct Scsi_Host *shost, Scsi_Device *sdev)
spin_lock_irqsave
(
shost
->
host_lock
,
flags
);
shost
->
host_busy
--
;
sdev
->
device_busy
--
;
if
(
shost
->
in_recovery
&&
shost
->
host_failed
&&
(
shost
->
host_busy
==
shost
->
host_failed
))
{
...
...
drivers/scsi/hosts.h
View file @
bee139b3
...
...
@@ -380,6 +380,7 @@ struct Scsi_Host
struct
scsi_host_cmd_pool
*
cmd_pool
;
spinlock_t
free_list_lock
;
struct
list_head
free_list
;
/* backup store of cmd structs */
struct
list_head
starved_list
;
spinlock_t
default_lock
;
spinlock_t
*
host_lock
;
...
...
@@ -470,12 +471,6 @@ struct Scsi_Host
*/
unsigned
reverse_ordering
:
1
;
/*
* Indicates that one or more devices on this host were starved, and
* when the device becomes less busy that we need to feed them.
*/
unsigned
some_device_starved
:
1
;
/*
* Host has rejected a command because it was busy.
*/
...
...
drivers/scsi/scsi.c
View file @
bee139b3
...
...
@@ -447,8 +447,6 @@ int scsi_dispatch_cmd(Scsi_Cmnd * SCpnt)
host
=
SCpnt
->
device
->
host
;
ASSERT_LOCK
(
host
->
host_lock
,
0
);
/* Assign a unique nonzero serial_number. */
if
(
++
serial_number
==
0
)
serial_number
=
1
;
...
...
@@ -574,8 +572,6 @@ void scsi_init_cmd_from_req(Scsi_Cmnd * SCpnt, Scsi_Request * SRpnt)
{
struct
Scsi_Host
*
host
=
SCpnt
->
device
->
host
;
ASSERT_LOCK
(
host
->
host_lock
,
0
);
SCpnt
->
owner
=
SCSI_OWNER_MIDLEVEL
;
SRpnt
->
sr_command
=
SCpnt
;
...
...
@@ -819,12 +815,11 @@ void scsi_finish_command(Scsi_Cmnd * SCpnt)
struct
Scsi_Host
*
host
;
Scsi_Device
*
device
;
Scsi_Request
*
SRpnt
;
unsigned
int
flags
;
host
=
SCpnt
->
device
->
host
;
device
=
SCpnt
->
device
;
ASSERT_LOCK
(
host
->
host_lock
,
0
);
/*
* We need to protect the decrement, as otherwise a race condition
* would exist. Fiddling with SCpnt isn't a problem as the
...
...
@@ -833,6 +828,9 @@ void scsi_finish_command(Scsi_Cmnd * SCpnt)
* shared.
*/
scsi_host_busy_dec_and_test
(
host
,
device
);
spin_lock_irqsave
(
SCpnt
->
device
->
request_queue
->
queue_lock
,
flags
);
SCpnt
->
device
->
device_busy
--
;
spin_unlock_irqrestore
(
SCpnt
->
device
->
request_queue
->
queue_lock
,
flags
);
/*
* Clear the flags which say that the device/host is no longer
...
...
drivers/scsi/scsi.h
View file @
bee139b3
...
...
@@ -417,7 +417,8 @@ extern void scsi_setup_cmd_retry(Scsi_Cmnd *SCpnt);
extern
void
scsi_io_completion
(
Scsi_Cmnd
*
SCpnt
,
int
good_sectors
,
int
block_sectors
);
extern
int
scsi_queue_insert
(
struct
scsi_cmnd
*
cmd
,
int
reason
);
extern
request_queue_t
*
scsi_alloc_queue
(
struct
Scsi_Host
*
shost
);
extern
void
scsi_queue_next_request
(
request_queue_t
*
q
,
struct
scsi_cmnd
*
cmd
);
extern
request_queue_t
*
scsi_alloc_queue
(
struct
scsi_device
*
sdev
);
extern
void
scsi_free_queue
(
request_queue_t
*
q
);
extern
int
scsi_init_queue
(
void
);
extern
void
scsi_exit_queue
(
void
);
...
...
@@ -530,6 +531,16 @@ struct scsi_dev_info_list {
extern
struct
list_head
scsi_dev_info_list
;
extern
int
scsi_dev_info_list_add_str
(
char
*
);
/*
* scsi_target: representation of a scsi target, for now, this is only
* used for single_lun devices. If no one has active IO to the target,
* starget_sdev_user is NULL, else it points to the active sdev.
*/
struct
scsi_target
{
struct
scsi_device
*
starget_sdev_user
;
unsigned
int
starget_refcnt
;
};
/*
* The scsi_device struct contains what we know about each given scsi
* device.
...
...
@@ -554,8 +565,10 @@ struct scsi_device {
struct
Scsi_Host
*
host
;
request_queue_t
*
request_queue
;
volatile
unsigned
short
device_busy
;
/* commands actually active on low-level */
spinlock_t
sdev_lock
;
/* also the request queue_lock */
spinlock_t
list_lock
;
struct
list_head
cmd_list
;
/* queue of in use SCSI Command structures */
struct
list_head
starved_entry
;
Scsi_Cmnd
*
current_cmnd
;
/* currently active command */
unsigned
short
queue_depth
;
/* How deep of a queue we want */
unsigned
short
last_queue_full_depth
;
/* These two are used by */
...
...
@@ -586,6 +599,7 @@ struct scsi_device {
unsigned
char
current_tag
;
/* current tag */
// unsigned char sync_min_period; /* Not less than this period */
// unsigned char sync_max_offset; /* Not greater than this offset */
struct
scsi_target
*
sdev_target
;
/* used only for single_lun */
unsigned
online
:
1
;
unsigned
writeable
:
1
;
...
...
@@ -616,8 +630,6 @@ struct scsi_device {
* because we did a bus reset. */
unsigned
ten
:
1
;
/* support ten byte read / write */
unsigned
remap
:
1
;
/* support remapping */
unsigned
starved
:
1
;
/* unable to process commands because
host busy */
// unsigned sync:1; /* Sync transfer state, managed by host */
// unsigned wide:1; /* WIDE transfer state, managed by host */
...
...
drivers/scsi/scsi_error.c
View file @
bee139b3
...
...
@@ -431,8 +431,6 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, int timeout)
unsigned
long
flags
;
int
rtn
=
SUCCESS
;
ASSERT_LOCK
(
host
->
host_lock
,
0
);
/*
* we will use a queued command if possible, otherwise we will
* emulate the queuing and calling of completion function ourselves.
...
...
@@ -1405,8 +1403,6 @@ static void scsi_restart_operations(struct Scsi_Host *shost)
struct
scsi_device
*
sdev
;
unsigned
long
flags
;
ASSERT_LOCK
(
shost
->
host_lock
,
0
);
/*
* If the door was locked, we need to insert a door lock request
* onto the head of the SCSI request queue for the device. There
...
...
@@ -1434,18 +1430,11 @@ static void scsi_restart_operations(struct Scsi_Host *shost)
* now that error recovery is done, we will need to ensure that these
* requests are started.
*/
spin_lock_irqsave
(
shost
->
host_lock
,
flags
);
list_for_each_entry
(
sdev
,
&
shost
->
my_devices
,
siblings
)
{
if
((
shost
->
can_queue
>
0
&&
(
shost
->
host_busy
>=
shost
->
can_queue
))
||
(
shost
->
host_blocked
)
||
(
shost
->
host_self_blocked
))
{
break
;
}
spin_lock_irqsave
(
sdev
->
request_queue
->
queue_lock
,
flags
);
__blk_run_queue
(
sdev
->
request_queue
);
spin_unlock_irqrestore
(
sdev
->
request_queue
->
queue_lock
,
flags
);
}
spin_unlock_irqrestore
(
shost
->
host_lock
,
flags
);
}
/**
...
...
@@ -1681,6 +1670,7 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
struct
scsi_cmnd
*
scmd
=
scsi_get_command
(
dev
,
GFP_KERNEL
);
struct
request
req
;
int
rtn
;
struct
request_queue
*
q
;
scmd
->
request
=
&
req
;
memset
(
&
scmd
->
eh_timeout
,
0
,
sizeof
(
scmd
->
eh_timeout
));
...
...
@@ -1735,6 +1725,8 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
}
scsi_delete_timer
(
scmd
);
q
=
scmd
->
device
->
request_queue
;
scsi_put_command
(
scmd
);
scsi_queue_next_request
(
q
,
NULL
);
return
rtn
;
}
drivers/scsi/scsi_lib.c
View file @
bee139b3
...
...
@@ -92,6 +92,7 @@ int scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
{
struct
Scsi_Host
*
host
=
cmd
->
device
->
host
;
struct
scsi_device
*
device
=
cmd
->
device
;
unsigned
long
flags
;
SCSI_LOG_MLQUEUE
(
1
,
printk
(
"Inserting command %p into mlqueue
\n
"
,
cmd
));
...
...
@@ -130,6 +131,9 @@ int scsi_queue_insert(struct scsi_cmnd *cmd, int reason)
* Decrement the counters, since these commands are no longer
* active on the host/device.
*/
spin_lock_irqsave
(
device
->
request_queue
->
queue_lock
,
flags
);
device
->
device_busy
--
;
spin_unlock_irqrestore
(
device
->
request_queue
->
queue_lock
,
flags
);
scsi_host_busy_dec_and_test
(
host
,
device
);
/*
...
...
@@ -174,14 +178,18 @@ void scsi_do_req(struct scsi_request *sreq, const void *cmnd,
void
(
*
done
)(
struct
scsi_cmnd
*
),
int
timeout
,
int
retries
)
{
struct
request_queue
*
q
;
/*
* If the upper level driver is reusing these things, then
* we should release the low-level block now. Another one will
* be allocated later when this request is getting queued.
*/
if
(
sreq
->
sr_command
)
{
q
=
sreq
->
sr_command
->
device
->
request_queue
;
scsi_put_command
(
sreq
->
sr_command
);
sreq
->
sr_command
=
NULL
;
scsi_queue_next_request
(
q
,
NULL
);
}
/*
...
...
@@ -228,6 +236,7 @@ static void scsi_wait_done(struct scsi_cmnd *cmd)
void
scsi_wait_req
(
struct
scsi_request
*
sreq
,
const
void
*
cmnd
,
void
*
buffer
,
unsigned
bufflen
,
int
timeout
,
int
retries
)
{
struct
request_queue
*
q
;
DECLARE_COMPLETION
(
wait
);
sreq
->
sr_request
->
waiting
=
&
wait
;
...
...
@@ -239,7 +248,9 @@ void scsi_wait_req(struct scsi_request *sreq, const void *cmnd, void *buffer,
sreq
->
sr_request
->
waiting
=
NULL
;
if
(
sreq
->
sr_command
)
{
q
=
sreq
->
sr_command
->
device
->
request_queue
;
scsi_put_command
(
sreq
->
sr_command
);
scsi_queue_next_request
(
q
,
NULL
);
sreq
->
sr_command
=
NULL
;
}
}
...
...
@@ -315,6 +326,53 @@ void scsi_setup_cmd_retry(struct scsi_cmnd *cmd)
cmd
->
underflow
=
cmd
->
old_underflow
;
}
/*
* Called for single_lun devices on IO completion. Clear starget_sdev_user,
* and call __blk_run_queue for all the scsi_devices on the target -
* including current_sdev first.
*
* Called with *no* scsi locks held.
*/
static
void
scsi_single_lun_run
(
struct
scsi_device
*
current_sdev
)
{
struct
scsi_device
*
sdev
;
unsigned
int
flags
,
flags2
;
spin_lock_irqsave
(
current_sdev
->
host
->
host_lock
,
flags
);
WARN_ON
(
!
current_sdev
->
sdev_target
->
starget_sdev_user
);
current_sdev
->
sdev_target
->
starget_sdev_user
=
NULL
;
spin_unlock_irqrestore
(
current_sdev
->
host
->
host_lock
,
flags
);
/*
* Call __blk_run_queue for all LUNs on the target, starting with
* current_sdev. We race with others (to set starget_sdev_user),
* but in most cases, we will be first. Ideally, each LU on the
* target would get some limited time or requests on the target.
*/
spin_lock_irqsave
(
current_sdev
->
request_queue
->
queue_lock
,
flags2
);
__blk_run_queue
(
current_sdev
->
request_queue
);
spin_unlock_irqrestore
(
current_sdev
->
request_queue
->
queue_lock
,
flags2
);
spin_lock_irqsave
(
current_sdev
->
host
->
host_lock
,
flags
);
if
(
current_sdev
->
sdev_target
->
starget_sdev_user
)
{
/*
* After unlock, this races with anyone clearing
* starget_sdev_user, but we (should) always enter this
* function again, avoiding any problems.
*/
spin_unlock_irqrestore
(
current_sdev
->
host
->
host_lock
,
flags
);
return
;
}
spin_unlock_irqrestore
(
current_sdev
->
host
->
host_lock
,
flags
);
list_for_each_entry
(
sdev
,
&
current_sdev
->
same_target_siblings
,
same_target_siblings
)
{
spin_lock_irqsave
(
sdev
->
request_queue
->
queue_lock
,
flags2
);
__blk_run_queue
(
sdev
->
request_queue
);
spin_unlock_irqrestore
(
sdev
->
request_queue
->
queue_lock
,
flags2
);
}
}
/*
* Function: scsi_queue_next_request()
*
...
...
@@ -351,16 +409,12 @@ void scsi_setup_cmd_retry(struct scsi_cmnd *cmd)
* permutations grows as 2**N, and if too many more special cases
* get added, we start to get screwed.
*/
static
void
scsi_queue_next_request
(
request_queue_t
*
q
,
struct
scsi_cmnd
*
cmd
)
void
scsi_queue_next_request
(
request_queue_t
*
q
,
struct
scsi_cmnd
*
cmd
)
{
struct
scsi_device
*
sdev
,
*
sdev2
;
struct
scsi_device
*
sdev
;
struct
Scsi_Host
*
shost
;
unsigned
long
flags
;
int
all_clear
;
ASSERT_LOCK
(
q
->
queue_lock
,
0
);
spin_lock_irqsave
(
q
->
queue_lock
,
flags
);
if
(
cmd
!=
NULL
)
{
/*
...
...
@@ -369,6 +423,7 @@ static void scsi_queue_next_request(request_queue_t *q, struct scsi_cmnd *cmd)
* in which case we need to request the blocks that come after
* the bad sector.
*/
spin_lock_irqsave
(
q
->
queue_lock
,
flags
);
cmd
->
request
->
special
=
cmd
;
if
(
blk_rq_tagged
(
cmd
->
request
))
blk_queue_end_tag
(
q
,
cmd
->
request
);
...
...
@@ -381,62 +436,52 @@ static void scsi_queue_next_request(request_queue_t *q, struct scsi_cmnd *cmd)
cmd
->
request
->
flags
|=
REQ_SPECIAL
;
cmd
->
request
->
flags
&=
~
REQ_DONTPREP
;
__elv_add_request
(
q
,
cmd
->
request
,
0
,
0
);
spin_unlock_irqrestore
(
q
->
queue_lock
,
flags
);
}
/*
* Just hit the requeue function for the queue.
*/
__blk_run_queue
(
q
);
sdev
=
q
->
queuedata
;
shost
=
sdev
->
host
;
if
(
sdev
->
single_lun
)
scsi_single_lun_run
(
sdev
);
shost
=
sdev
->
host
;
spin_lock_irqsave
(
shost
->
host_lock
,
flags
);
while
(
!
list_empty
(
&
shost
->
starved_list
)
&&
!
shost
->
host_blocked
&&
!
shost
->
host_self_blocked
&&
!
((
shost
->
can_queue
>
0
)
&&
(
shost
->
host_busy
>=
shost
->
can_queue
)))
{
/*
* If this is a single-lun device, and we are currently finished
* with this device, then see if we need to get another device
* started. FIXME(eric) - if this function gets too cluttered
* with special case code, then spin off separate versions and
* use function pointers to pick the right one.
* As long as shost is accepting commands and we have
* starved queues, call __blk_run_queue. scsi_request_fn
* drops the queue_lock and can add us back to the
* starved_list.
*
* host_lock protects the starved_list and starved_entry.
* scsi_request_fn must get the host_lock before checking
* or modifying starved_list or starved_entry.
*/
if
(
sdev
->
single_lun
&&
sdev
->
device_busy
==
0
&&
!
shost
->
host_blocked
&&
!
shost
->
host_self_blocked
&&
!
((
shost
->
can_queue
>
0
)
&&
(
shost
->
host_busy
>=
shost
->
can_queue
))
&&
elv_queue_empty
(
q
))
{
list_for_each_entry
(
sdev2
,
&
sdev
->
same_target_siblings
,
same_target_siblings
)
{
if
(
!
sdev2
->
device_blocked
&&
!
elv_queue_empty
(
sdev2
->
request_queue
))
{
__blk_run_queue
(
sdev2
->
request_queue
);
break
;
}
}
}
sdev
=
list_entry
(
shost
->
starved_list
.
next
,
struct
scsi_device
,
starved_entry
);
list_del_init
(
&
sdev
->
starved_entry
);
spin_unlock_irqrestore
(
shost
->
host_lock
,
flags
);
spin_lock_irqsave
(
sdev
->
request_queue
->
queue_lock
,
flags
);
__blk_run_queue
(
sdev
->
request_queue
);
spin_unlock_irqrestore
(
sdev
->
request_queue
->
queue_lock
,
flags
);
spin_lock_irqsave
(
shost
->
host_lock
,
flags
);
if
(
unlikely
(
!
list_empty
(
&
sdev
->
starved_entry
)))
/*
* Now see whether there are other devices on the bus which
* might be starved. If so, hit the request function. If we
* don't find any, then it is safe to reset the flag. If we
* find any device that it is starved, it isn't safe to reset the
* flag as the queue function releases the lock and thus some
* other device might have become starved along the way.
*/
all_clear
=
1
;
if
(
shost
->
some_device_starved
)
{
list_for_each_entry
(
sdev
,
&
shost
->
my_devices
,
siblings
)
{
if
(
shost
->
can_queue
>
0
&&
shost
->
host_busy
>=
shost
->
can_queue
)
break
;
if
(
shost
->
host_blocked
||
shost
->
host_self_blocked
)
* sdev lost a race, and was put back on the
* starved list. This is unlikely but without this
* in theory we could loop forever.
*/
break
;
if
(
sdev
->
device_blocked
||
!
sdev
->
starved
)
continue
;
__blk_run_queue
(
sdev
->
request_queue
);
all_clear
=
0
;
}
spin_unlock_irqrestore
(
shost
->
host_lock
,
flags
);
if
(
sdev
==
NULL
&&
all_clear
)
shost
->
some_device_starved
=
0
;
}
spin_lock_irqsave
(
q
->
queue_lock
,
flags
);
__blk_run_queue
(
q
);
spin_unlock_irqrestore
(
q
->
queue_lock
,
flags
);
}
...
...
@@ -470,8 +515,6 @@ static struct scsi_cmnd *scsi_end_request(struct scsi_cmnd *cmd, int uptodate,
struct
request
*
req
=
cmd
->
request
;
unsigned
long
flags
;
ASSERT_LOCK
(
q
->
queue_lock
,
0
);
/*
* If there are blocks left over at the end, set up the command
* to queue the remainder of them.
...
...
@@ -569,8 +612,6 @@ static void scsi_release_buffers(struct scsi_cmnd *cmd)
{
struct
request
*
req
=
cmd
->
request
;
ASSERT_LOCK
(
cmd
->
device
->
host
->
host_lock
,
0
);
/*
* Free up any indirection buffers we allocated for DMA purposes.
*/
...
...
@@ -651,8 +692,6 @@ void scsi_io_completion(struct scsi_cmnd *cmd, int good_sectors,
* would be used if we just wanted to retry, for example.
*
*/
ASSERT_LOCK
(
q
->
queue_lock
,
0
);
/*
* Free up any indirection buffers we allocated for DMA purposes.
* For the case of a READ, we need to copy the data out of the
...
...
@@ -923,22 +962,6 @@ static int scsi_init_io(struct scsi_cmnd *cmd)
return
BLKPREP_KILL
;
}
/*
* The target associated with myself can only handle one active command at
* a time. Scan through all of the luns on the same target as myself,
* return 1 if any are active.
*/
static
int
check_all_luns
(
struct
scsi_device
*
myself
)
{
struct
scsi_device
*
sdev
;
list_for_each_entry
(
sdev
,
&
myself
->
same_target_siblings
,
same_target_siblings
)
if
(
sdev
->
device_busy
)
return
1
;
return
0
;
}
static
int
scsi_prep_fn
(
struct
request_queue
*
q
,
struct
request
*
req
)
{
struct
Scsi_Device_Template
*
sdt
;
...
...
@@ -1039,6 +1062,74 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
return
BLKPREP_OK
;
}
/*
* scsi_dev_queue_ready: if we can send requests to sdev, return 1 else
* return 0.
*
* Called with the queue_lock held.
*/
static
inline
int
scsi_dev_queue_ready
(
struct
request_queue
*
q
,
struct
scsi_device
*
sdev
)
{
if
(
sdev
->
device_busy
>=
sdev
->
queue_depth
)
return
0
;
if
(
sdev
->
device_busy
==
0
&&
sdev
->
device_blocked
)
{
/*
* unblock after device_blocked iterates to zero
*/
if
(
--
sdev
->
device_blocked
==
0
)
{
SCSI_LOG_MLQUEUE
(
3
,
printk
(
"scsi%d (%d:%d) unblocking device at"
" zero depth
\n
"
,
sdev
->
host
->
host_no
,
sdev
->
id
,
sdev
->
lun
));
}
else
{
blk_plug_device
(
q
);
return
0
;
}
}
if
(
sdev
->
device_blocked
)
return
0
;
return
1
;
}
/*
* scsi_host_queue_ready: if we can send requests to shost, return 1 else
* return 0. We must end up running the queue again whenever 0 is
* returned, else IO can hang.
*
* Called with host_lock held.
*/
static
inline
int
scsi_host_queue_ready
(
struct
request_queue
*
q
,
struct
Scsi_Host
*
shost
,
struct
scsi_device
*
sdev
)
{
if
(
shost
->
in_recovery
)
return
0
;
if
(
shost
->
host_busy
==
0
&&
shost
->
host_blocked
)
{
/*
* unblock after host_blocked iterates to zero
*/
if
(
--
shost
->
host_blocked
==
0
)
{
SCSI_LOG_MLQUEUE
(
3
,
printk
(
"scsi%d unblocking host at zero depth
\n
"
,
shost
->
host_no
));
}
else
{
blk_plug_device
(
q
);
return
0
;
}
}
if
(
!
list_empty
(
&
sdev
->
starved_entry
))
return
0
;
if
((
shost
->
can_queue
>
0
&&
shost
->
host_busy
>=
shost
->
can_queue
)
||
shost
->
host_blocked
||
shost
->
host_self_blocked
)
{
list_add_tail
(
&
sdev
->
starved_entry
,
&
shost
->
starved_list
);
return
0
;
}
return
1
;
}
/*
* Function: scsi_request_fn()
*
...
...
@@ -1056,92 +1147,61 @@ static void scsi_request_fn(request_queue_t *q)
struct
Scsi_Host
*
shost
=
sdev
->
host
;
struct
scsi_cmnd
*
cmd
;
struct
request
*
req
;
ASSERT_LOCK
(
q
->
queue_lock
,
1
);
unsigned
int
flags
;
/*
* To start with, we keep looping until the queue is empty, or until
* the host is no longer able to accept any more requests.
*/
for
(;;)
{
if
(
blk_queue_plugged
(
q
))
goto
completed
;
/*
*
Check this again - each time we loop through we will hav
e
*
released the lock and grabbed it again, so each time
*
we need to check to see if the queue is plugged or no
t.
*
get next queueable request. We do this early to make sur
e
*
that the request is fully prepared even if we cannot
*
accept i
t.
*/
if
(
shost
->
in_recovery
||
blk_queue_plugged
(
q
))
return
;
if
(
sdev
->
device_busy
>=
sdev
->
queue_depth
)
break
;
if
(
sdev
->
single_lun
&&
check_all_luns
(
sdev
))
break
;
req
=
elv_next_request
(
q
);
if
(
shost
->
host_busy
==
0
&&
shost
->
host_blocked
)
{
/*
unblock after host_blocked iterates to zero */
if
(
--
shost
->
host_blocked
==
0
)
{
SCSI_LOG_MLQUEUE
(
3
,
printk
(
"scsi%d unblocking host at zero depth
\n
"
,
shost
->
host_no
));
}
else
{
if
(
!
req
)
{
/*
* If the device is busy, a returning I/O will
* restart the queue. Otherwise, we have to plug
* the queue
*/
if
(
sdev
->
device_busy
==
0
)
blk_plug_device
(
q
);
break
;
}
goto
completed
;
}
if
(
sdev
->
device_busy
==
0
&&
sdev
->
device_blocked
)
{
/* unblock after device_blocked iterates to zero */
if
(
--
sdev
->
device_blocked
==
0
)
{
SCSI_LOG_MLQUEUE
(
3
,
printk
(
"scsi%d (%d:%d) unblocking device at zero depth
\n
"
,
shost
->
host_no
,
sdev
->
id
,
sdev
->
lun
));
}
else
{
blk_plug_device
(
q
);
break
;
}
}
if
(
!
scsi_dev_queue_ready
(
q
,
sdev
))
goto
completed
;
/*
*
If the device cannot accept another request, then qui
t.
*
Remove the request from the request lis
t.
*/
if
(
sdev
->
device_blocked
)
break
;
if
((
shost
->
can_queue
>
0
&&
shost
->
host_busy
>=
shost
->
can_queue
)
||
shost
->
host_blocked
||
shost
->
host_self_blocked
)
{
/*
* If we are unable to process any commands at all for
* this device, then we consider it to be starved.
* What this means is that there are no outstanding
* commands for this device and hence we need a
* little help getting it started again
* once the host isn't quite so busy.
*/
if
(
sdev
->
device_busy
==
0
)
{
sdev
->
starved
=
1
;
shost
->
some_device_starved
=
1
;
}
break
;
}
else
sdev
->
starved
=
0
;
if
(
!
(
blk_queue_tagged
(
q
)
&&
(
blk_queue_start_tag
(
q
,
req
)
==
0
)))
blkdev_dequeue_request
(
req
);
/*
* get next queueable request. We do this early to make sure
* that the request is fully prepared even if we cannot
* accept it. If there is no request, we'll detect this
* lower down.
*/
req
=
elv_next_request
(
q
);
sdev
->
device_busy
++
;
spin_unlock_irq
(
q
->
queue_lock
);
if
(
!
req
)
{
/* If the device is busy, a returning I/O
* will restart the queue. Otherwise, we have
* to plug the queue */
if
(
sdev
->
device_busy
==
0
)
blk_plug_device
(
q
);
break
;
spin_lock_irqsave
(
shost
->
host_lock
,
flags
);
if
(
!
scsi_host_queue_ready
(
q
,
shost
,
sdev
))
goto
host_lock_held
;
if
(
sdev
->
single_lun
)
{
if
(
sdev
->
sdev_target
->
starget_sdev_user
&&
(
sdev
->
sdev_target
->
starget_sdev_user
!=
sdev
))
goto
host_lock_held
;
else
sdev
->
sdev_target
->
starget_sdev_user
=
sdev
;
}
shost
->
host_busy
++
;
spin_unlock_irqrestore
(
shost
->
host_lock
,
flags
);
cmd
=
req
->
special
;
/*
...
...
@@ -1150,25 +1210,6 @@ static void scsi_request_fn(request_queue_t *q)
*/
BUG_ON
(
!
cmd
);
/*
* Finally, before we release the lock, we copy the
* request to the command block, and remove the
* request from the request list. Note that we always
* operate on the queue head - there is absolutely no
* reason to search the list, because all of the
* commands in this queue are for the same device.
*/
if
(
!
(
blk_queue_tagged
(
q
)
&&
(
blk_queue_start_tag
(
q
,
req
)
==
0
)))
blkdev_dequeue_request
(
req
);
/*
* Now bump the usage count for both the host and the
* device.
*/
shost
->
host_busy
++
;
sdev
->
device_busy
++
;
spin_unlock_irq
(
q
->
queue_lock
);
/*
* Finally, initialize any error handling parameters, and set up
* the timers for timeouts.
...
...
@@ -1186,6 +1227,24 @@ static void scsi_request_fn(request_queue_t *q)
*/
spin_lock_irq
(
q
->
queue_lock
);
}
completed:
return
;
host_lock_held:
spin_unlock_irqrestore
(
shost
->
host_lock
,
flags
);
/*
* lock q, handle tag, requeue req, and decrement device_busy. We
* must return with queue_lock held.
*
* Decrementing device_busy without checking it is OK, as all such
* cases (host limits or settings) should run the queue at some
* later time.
*/
spin_lock_irq
(
q
->
queue_lock
);
if
(
blk_rq_tagged
(
req
))
blk_queue_end_tag
(
q
,
req
);
__elv_add_request
(
q
,
req
,
0
,
0
);
sdev
->
device_busy
--
;
}
u64
scsi_calculate_bounce_limit
(
struct
Scsi_Host
*
shost
)
...
...
@@ -1207,15 +1266,20 @@ u64 scsi_calculate_bounce_limit(struct Scsi_Host *shost)
return
BLK_BOUNCE_HIGH
;
}
request_queue_t
*
scsi_alloc_queue
(
struct
Scsi_Host
*
shost
)
request_queue_t
*
scsi_alloc_queue
(
struct
scsi_device
*
sdev
)
{
request_queue_t
*
q
;
struct
Scsi_Host
*
shost
;
q
=
kmalloc
(
sizeof
(
*
q
),
GFP_ATOMIC
);
if
(
!
q
)
return
NULL
;
memset
(
q
,
0
,
sizeof
(
*
q
));
/*
* XXX move host code to scsi_register
*/
shost
=
sdev
->
host
;
if
(
!
shost
->
max_sectors
)
{
/*
* Driver imposes no hard sector transfer limit.
...
...
@@ -1224,7 +1288,7 @@ request_queue_t *scsi_alloc_queue(struct Scsi_Host *shost)
shost
->
max_sectors
=
SCSI_DEFAULT_MAX_SECTORS
;
}
blk_init_queue
(
q
,
scsi_request_fn
,
shost
->
host
_lock
);
blk_init_queue
(
q
,
scsi_request_fn
,
&
sdev
->
sdev
_lock
);
blk_queue_prep_rq
(
q
,
scsi_prep_fn
);
blk_queue_max_hw_segments
(
q
,
shost
->
sg_tablesize
);
...
...
drivers/scsi/scsi_scan.c
View file @
bee139b3
...
...
@@ -387,7 +387,7 @@ static void print_inquiry(unsigned char *inq_result)
* Scsi_Device pointer, or NULL on failure.
**/
static
struct
scsi_device
*
scsi_alloc_sdev
(
struct
Scsi_Host
*
shost
,
struct
request_queue
**
q
,
uint
channel
,
uint
id
,
uint
lun
)
uint
channel
,
uint
id
,
uint
lun
)
{
struct
scsi_device
*
sdev
,
*
device
;
...
...
@@ -407,6 +407,7 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
INIT_LIST_HEAD
(
&
sdev
->
siblings
);
INIT_LIST_HEAD
(
&
sdev
->
same_target_siblings
);
INIT_LIST_HEAD
(
&
sdev
->
cmd_list
);
INIT_LIST_HEAD
(
&
sdev
->
starved_entry
);
spin_lock_init
(
&
sdev
->
list_lock
);
/*
...
...
@@ -421,14 +422,10 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
*/
sdev
->
borken
=
1
;
if
(
!
q
||
*
q
==
NULL
)
{
sdev
->
request_queue
=
scsi_alloc_queue
(
shost
);
spin_lock_init
(
&
sdev
->
sdev_lock
);
sdev
->
request_queue
=
scsi_alloc_queue
(
sdev
);
if
(
!
sdev
->
request_queue
)
goto
out_free_dev
;
}
else
{
sdev
->
request_queue
=
*
q
;
*
q
=
NULL
;
}
sdev
->
request_queue
->
queuedata
=
sdev
;
scsi_adjust_queue_depth
(
sdev
,
0
,
sdev
->
host
->
cmd_per_lun
);
...
...
@@ -468,10 +465,7 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
return
sdev
;
out_free_queue:
if
(
q
&&
sdev
->
request_queue
)
{
*
q
=
sdev
->
request_queue
;
sdev
->
request_queue
=
NULL
;
}
else
if
(
sdev
->
request_queue
)
if
(
sdev
->
request_queue
)
scsi_free_queue
(
sdev
->
request_queue
);
out_free_dev:
...
...
@@ -491,6 +485,8 @@ static struct scsi_device *scsi_alloc_sdev(struct Scsi_Host *shost,
**/
static
void
scsi_free_sdev
(
struct
scsi_device
*
sdev
)
{
unsigned
int
flags
;
list_del
(
&
sdev
->
siblings
);
list_del
(
&
sdev
->
same_target_siblings
);
...
...
@@ -500,6 +496,15 @@ static void scsi_free_sdev(struct scsi_device *sdev)
sdev
->
host
->
hostt
->
slave_destroy
(
sdev
);
if
(
sdev
->
inquiry
)
kfree
(
sdev
->
inquiry
);
spin_lock_irqsave
(
sdev
->
host
->
host_lock
,
flags
);
list_del
(
&
sdev
->
starved_entry
);
if
(
sdev
->
single_lun
)
{
sdev
->
sdev_target
->
starget_refcnt
--
;
if
(
sdev
->
sdev_target
->
starget_refcnt
==
0
)
kfree
(
sdev
->
sdev_target
);
}
spin_unlock_irqrestore
(
sdev
->
host
->
host_lock
,
flags
);
kfree
(
sdev
);
}
...
...
@@ -1135,6 +1140,10 @@ static void scsi_probe_lun(Scsi_Request *sreq, char *inq_result,
static
int
scsi_add_lun
(
Scsi_Device
*
sdev
,
Scsi_Request
*
sreq
,
char
*
inq_result
,
int
*
bflags
)
{
struct
scsi_device
*
sdev_sibling
;
struct
scsi_target
*
starget
;
unsigned
int
flags
;
/*
* XXX do not save the inquiry, since it can change underneath us,
* save just vendor/model/rev.
...
...
@@ -1256,10 +1265,38 @@ static int scsi_add_lun(Scsi_Device *sdev, Scsi_Request *sreq,
/*
* If we need to allow I/O to only one of the luns attached to
* this target id at a time, then we set this flag.
* this target id at a time set single_lun, and allocate or modify
* sdev_target.
*/
if
(
*
bflags
&
BLIST_SINGLELUN
)
if
(
*
bflags
&
BLIST_SINGLELUN
)
{
sdev
->
single_lun
=
1
;
spin_lock_irqsave
(
sdev
->
host
->
host_lock
,
flags
);
starget
=
NULL
;
/*
* Search for an existing target for this sdev.
*/
list_for_each_entry
(
sdev_sibling
,
&
sdev
->
same_target_siblings
,
same_target_siblings
)
{
if
(
sdev_sibling
->
sdev_target
!=
NULL
)
{
starget
=
sdev_sibling
->
sdev_target
;
break
;
}
}
if
(
!
starget
)
{
starget
=
kmalloc
(
sizeof
(
*
starget
),
GFP_ATOMIC
);
if
(
!
starget
)
{
printk
(
ALLOC_FAILURE_MSG
,
__FUNCTION__
);
spin_unlock_irqrestore
(
sdev
->
host
->
host_lock
,
flags
);
return
SCSI_SCAN_NO_RESPONSE
;
}
starget
->
starget_refcnt
=
0
;
starget
->
starget_sdev_user
=
NULL
;
}
starget
->
starget_refcnt
++
;
sdev
->
sdev_target
=
starget
;
spin_unlock_irqrestore
(
sdev
->
host
->
host_lock
,
flags
);
}
/* if the device needs this changing, it may do so in the detect
* function */
...
...
@@ -1288,15 +1325,15 @@ static int scsi_add_lun(Scsi_Device *sdev, Scsi_Request *sreq,
* SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
**/
static
int
scsi_probe_and_add_lun
(
struct
Scsi_Host
*
host
,
struct
request_queue
**
q
,
uint
channel
,
uint
id
,
uint
lun
,
int
*
bflagsp
,
struct
scsi_device
**
sdevp
)
uint
channel
,
uint
id
,
uint
lun
,
int
*
bflagsp
,
struct
scsi_device
**
sdevp
)
{
struct
scsi_device
*
sdev
;
struct
scsi_request
*
sreq
;
unsigned
char
*
result
;
int
bflags
,
res
=
SCSI_SCAN_NO_RESPONSE
;
sdev
=
scsi_alloc_sdev
(
host
,
q
,
channel
,
id
,
lun
);
sdev
=
scsi_alloc_sdev
(
host
,
channel
,
id
,
lun
);
if
(
!
sdev
)
goto
out
;
sreq
=
scsi_allocate_request
(
sdev
);
...
...
@@ -1350,13 +1387,8 @@ static int scsi_probe_and_add_lun(struct Scsi_Host *host,
if
(
res
==
SCSI_SCAN_LUN_PRESENT
)
{
if
(
sdevp
)
*
sdevp
=
sdev
;
}
else
{
if
(
q
)
{
*
q
=
sdev
->
request_queue
;
sdev
->
request_queue
=
NULL
;
}
}
else
scsi_free_sdev
(
sdev
);
}
out:
return
res
;
}
...
...
@@ -1374,9 +1406,8 @@ static int scsi_probe_and_add_lun(struct Scsi_Host *host,
*
* Modifies sdevscan->lun.
**/
static
void
scsi_sequential_lun_scan
(
struct
Scsi_Host
*
shost
,
struct
request_queue
**
q
,
uint
channel
,
uint
id
,
int
bflags
,
int
lun0_res
,
int
scsi_level
)
static
void
scsi_sequential_lun_scan
(
struct
Scsi_Host
*
shost
,
uint
channel
,
uint
id
,
int
bflags
,
int
lun0_res
,
int
scsi_level
)
{
unsigned
int
sparse_lun
,
lun
,
max_dev_lun
;
...
...
@@ -1444,7 +1475,7 @@ static void scsi_sequential_lun_scan(struct Scsi_Host *shost,
* sparse_lun.
*/
for
(
lun
=
1
;
lun
<
max_dev_lun
;
++
lun
)
if
((
scsi_probe_and_add_lun
(
shost
,
q
,
channel
,
id
,
lun
,
if
((
scsi_probe_and_add_lun
(
shost
,
channel
,
id
,
lun
,
NULL
,
NULL
)
!=
SCSI_SCAN_LUN_PRESENT
)
&&
!
sparse_lun
)
return
;
}
...
...
@@ -1497,8 +1528,7 @@ static int scsilun_to_int(ScsiLun *scsilun)
* 0: scan completed (or no memory, so further scanning is futile)
* 1: no report lun scan, or not configured
**/
static
int
scsi_report_lun_scan
(
Scsi_Device
*
sdev
,
struct
request_queue
**
q
,
int
bflags
)
static
int
scsi_report_lun_scan
(
Scsi_Device
*
sdev
,
int
bflags
)
{
#ifdef CONFIG_SCSI_REPORT_LUNS
...
...
@@ -1659,8 +1689,8 @@ static int scsi_report_lun_scan(Scsi_Device *sdev, struct request_queue **q,
}
else
{
int
res
;
res
=
scsi_probe_and_add_lun
(
sdev
->
host
,
q
,
sdev
->
channel
,
sdev
->
id
,
lun
,
NULL
,
NULL
);
res
=
scsi_probe_and_add_lun
(
sdev
->
host
,
sdev
->
channel
,
sdev
->
id
,
lun
,
NULL
,
NULL
);
if
(
res
==
SCSI_SCAN_NO_RESPONSE
)
{
/*
* Got some results, but now none, abort.
...
...
@@ -1688,8 +1718,7 @@ struct scsi_device *scsi_add_device(struct Scsi_Host *shost,
struct
scsi_device
*
sdev
;
int
error
=
-
ENODEV
,
res
;
res
=
scsi_probe_and_add_lun
(
shost
,
NULL
,
channel
,
id
,
lun
,
NULL
,
&
sdev
);
res
=
scsi_probe_and_add_lun
(
shost
,
channel
,
id
,
lun
,
NULL
,
&
sdev
);
if
(
res
==
SCSI_SCAN_LUN_PRESENT
)
error
=
scsi_attach_device
(
sdev
);
...
...
@@ -1730,8 +1759,8 @@ int scsi_remove_device(struct scsi_device *sdev)
* First try a REPORT LUN scan, if that does not scan the target, do a
* sequential scan of LUNs on the target id.
**/
static
void
scsi_scan_target
(
struct
Scsi_Host
*
shost
,
struct
request_queue
**
q
,
unsigned
int
channel
,
unsigned
int
id
)
static
void
scsi_scan_target
(
struct
Scsi_Host
*
shost
,
unsigned
int
channel
,
unsigned
int
id
)
{
int
bflags
=
0
;
int
res
;
...
...
@@ -1747,14 +1776,14 @@ static void scsi_scan_target(struct Scsi_Host *shost, struct request_queue **q,
* Scan LUN 0, if there is some response, scan further. Ideally, we
* would not configure LUN 0 until all LUNs are scanned.
*/
res
=
scsi_probe_and_add_lun
(
shost
,
q
,
channel
,
id
,
0
,
&
bflags
,
&
sdev
);
res
=
scsi_probe_and_add_lun
(
shost
,
channel
,
id
,
0
,
&
bflags
,
&
sdev
);
if
(
res
==
SCSI_SCAN_LUN_PRESENT
)
{
if
(
scsi_report_lun_scan
(
sdev
,
q
,
bflags
)
!=
0
)
if
(
scsi_report_lun_scan
(
sdev
,
bflags
)
!=
0
)
/*
* The REPORT LUN did not scan the target,
* do a sequential scan.
*/
scsi_sequential_lun_scan
(
shost
,
q
,
channel
,
id
,
bflags
,
scsi_sequential_lun_scan
(
shost
,
channel
,
id
,
bflags
,
res
,
sdev
->
scsi_level
);
}
else
if
(
res
==
SCSI_SCAN_TARGET_PRESENT
)
{
/*
...
...
@@ -1763,7 +1792,7 @@ static void scsi_scan_target(struct Scsi_Host *shost, struct request_queue **q,
* sequential lun scan with a bflags of SPARSELUN and
* a default scsi level of SCSI_2
*/
scsi_sequential_lun_scan
(
shost
,
q
,
channel
,
id
,
BLIST_SPARSELUN
,
scsi_sequential_lun_scan
(
shost
,
channel
,
id
,
BLIST_SPARSELUN
,
SCSI_SCAN_TARGET_PRESENT
,
SCSI_2
);
}
}
...
...
@@ -1778,7 +1807,6 @@ static void scsi_scan_target(struct Scsi_Host *shost, struct request_queue **q,
**/
void
scsi_scan_host
(
struct
Scsi_Host
*
shost
)
{
struct
request_queue
*
q
=
NULL
;
uint
channel
,
id
,
order_id
;
/*
...
...
@@ -1803,12 +1831,9 @@ void scsi_scan_host(struct Scsi_Host *shost)
order_id
=
shost
->
max_id
-
id
-
1
;
else
order_id
=
id
;
scsi_scan_target
(
shost
,
&
q
,
channel
,
order_id
);
scsi_scan_target
(
shost
,
channel
,
order_id
);
}
}
if
(
q
)
scsi_free_queue
(
q
);
}
void
scsi_forget_host
(
struct
Scsi_Host
*
shost
)
...
...
@@ -1847,7 +1872,7 @@ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
{
struct
scsi_device
*
sdev
;
sdev
=
scsi_alloc_sdev
(
shost
,
NULL
,
0
,
shost
->
this_id
,
0
);
sdev
=
scsi_alloc_sdev
(
shost
,
0
,
shost
->
this_id
,
0
);
if
(
sdev
)
{
sdev
->
borken
=
0
;
}
...
...
drivers/scsi/scsi_syms.c
View file @
bee139b3
...
...
@@ -60,6 +60,8 @@ EXPORT_SYMBOL(scsi_allocate_request);
EXPORT_SYMBOL
(
scsi_release_request
);
EXPORT_SYMBOL
(
scsi_wait_req
);
EXPORT_SYMBOL
(
scsi_do_req
);
EXPORT_SYMBOL
(
scsi_get_command
);
EXPORT_SYMBOL
(
scsi_put_command
);
EXPORT_SYMBOL
(
scsi_report_bus_reset
);
EXPORT_SYMBOL
(
scsi_block_requests
);
...
...
drivers/scsi/sd.c
View file @
bee139b3
...
...
@@ -123,7 +123,7 @@ static int sd_major(int major_idx)
case
1
...
7
:
return
SCSI_DISK1_MAJOR
+
major_idx
-
1
;
case
8
...
15
:
return
SCSI_DISK8_MAJOR
+
major_idx
;
return
SCSI_DISK8_MAJOR
+
major_idx
-
8
;
default:
BUG
();
return
0
;
/* shut up gcc */
...
...
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