From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Cc: Stefan Weinhuber <wein@de.ibm.com>,
Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: [patch 46/47] dasd: add hyper PAV support to DASD device driver, part 2
Date: Thu, 20 Dec 2007 16:20:11 +0100 [thread overview]
Message-ID: <20071220152113.078998892@de.ibm.com> (raw)
In-Reply-To: 20071220151925.405881218@de.ibm.com
[-- Attachment #1: 145-hyperpav-2.diff --]
[-- Type: text/plain, Size: 79278 bytes --]
From: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
drivers/s390/block/dasd.c | 1661 +++++++++++++++++++++++++---------------------
1 file changed, 938 insertions(+), 723 deletions(-)
Index: quilt-2.6/drivers/s390/block/dasd.c
===================================================================
--- quilt-2.6.orig/drivers/s390/block/dasd.c
+++ quilt-2.6/drivers/s390/block/dasd.c
@@ -48,13 +48,15 @@ MODULE_LICENSE("GPL");
/*
* SECTION: prototypes for static functions of dasd.c
*/
-static int dasd_alloc_queue(struct dasd_device * device);
-static void dasd_setup_queue(struct dasd_device * device);
-static void dasd_free_queue(struct dasd_device * device);
-static void dasd_flush_request_queue(struct dasd_device *);
-static int dasd_flush_ccw_queue(struct dasd_device *, int);
-static void dasd_tasklet(struct dasd_device *);
+static int dasd_alloc_queue(struct dasd_block *);
+static void dasd_setup_queue(struct dasd_block *);
+static void dasd_free_queue(struct dasd_block *);
+static void dasd_flush_request_queue(struct dasd_block *);
+static int dasd_flush_block_queue(struct dasd_block *);
+static void dasd_device_tasklet(struct dasd_device *);
+static void dasd_block_tasklet(struct dasd_block *);
static void do_kick_device(struct work_struct *);
+static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
/*
* SECTION: Operations on the device structure.
@@ -65,16 +67,13 @@ static wait_queue_head_t dasd_flush_wq;
/*
* Allocate memory for a new device structure.
*/
-struct dasd_device *
-dasd_alloc_device(void)
+struct dasd_device *dasd_alloc_device(void)
{
struct dasd_device *device;
- device = kzalloc(sizeof (struct dasd_device), GFP_ATOMIC);
+ device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
if (device == NULL)
return ERR_PTR(-ENOMEM);
- /* open_count = 0 means device online but not in use */
- atomic_set(&device->open_count, -1);
/* Get two pages for normal block device operations. */
device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
@@ -93,10 +92,9 @@ dasd_alloc_device(void)
dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
spin_lock_init(&device->mem_lock);
- spin_lock_init(&device->request_queue_lock);
- atomic_set (&device->tasklet_scheduled, 0);
+ atomic_set(&device->tasklet_scheduled, 0);
tasklet_init(&device->tasklet,
- (void (*)(unsigned long)) dasd_tasklet,
+ (void (*)(unsigned long)) dasd_device_tasklet,
(unsigned long) device);
INIT_LIST_HEAD(&device->ccw_queue);
init_timer(&device->timer);
@@ -110,8 +108,7 @@ dasd_alloc_device(void)
/*
* Free memory of a device structure.
*/
-void
-dasd_free_device(struct dasd_device *device)
+void dasd_free_device(struct dasd_device *device)
{
kfree(device->private);
free_page((unsigned long) device->erp_mem);
@@ -120,10 +117,42 @@ dasd_free_device(struct dasd_device *dev
}
/*
+ * Allocate memory for a new device structure.
+ */
+struct dasd_block *dasd_alloc_block(void)
+{
+ struct dasd_block *block;
+
+ block = kzalloc(sizeof(*block), GFP_ATOMIC);
+ if (block == NULL)
+ return ERR_PTR(-ENOMEM);
+ /* open_count = 0 means device online but not in use */
+ atomic_set(&block->open_count, -1);
+
+ spin_lock_init(&block->request_queue_lock);
+ atomic_set (&block->tasklet_scheduled, 0);
+ tasklet_init(&block->tasklet,
+ (void (*)(unsigned long)) dasd_block_tasklet,
+ (unsigned long) block);
+ INIT_LIST_HEAD(&block->ccw_queue);
+ spin_lock_init(&block->queue_lock);
+ init_timer(&block->timer);
+
+ return block;
+}
+
+/*
+ * Free memory of a device structure.
+ */
+void dasd_free_block(struct dasd_block *block)
+{
+ kfree(block);
+}
+
+/*
* Make a new device known to the system.
*/
-static int
-dasd_state_new_to_known(struct dasd_device *device)
+static int dasd_state_new_to_known(struct dasd_device *device)
{
int rc;
@@ -133,12 +162,13 @@ dasd_state_new_to_known(struct dasd_devi
*/
dasd_get_device(device);
- rc = dasd_alloc_queue(device);
- if (rc) {
- dasd_put_device(device);
- return rc;
+ if (device->block) {
+ rc = dasd_alloc_queue(device->block);
+ if (rc) {
+ dasd_put_device(device);
+ return rc;
+ }
}
-
device->state = DASD_STATE_KNOWN;
return 0;
}
@@ -146,21 +176,24 @@ dasd_state_new_to_known(struct dasd_devi
/*
* Let the system forget about a device.
*/
-static int
-dasd_state_known_to_new(struct dasd_device * device)
+static int dasd_state_known_to_new(struct dasd_device *device)
{
/* Disable extended error reporting for this device. */
dasd_eer_disable(device);
/* Forget the discipline information. */
- if (device->discipline)
+ if (device->discipline) {
+ if (device->discipline->uncheck_device)
+ device->discipline->uncheck_device(device);
module_put(device->discipline->owner);
+ }
device->discipline = NULL;
if (device->base_discipline)
module_put(device->base_discipline->owner);
device->base_discipline = NULL;
device->state = DASD_STATE_NEW;
- dasd_free_queue(device);
+ if (device->block)
+ dasd_free_queue(device->block);
/* Give up reference we took in dasd_state_new_to_known. */
dasd_put_device(device);
@@ -170,19 +203,19 @@ dasd_state_known_to_new(struct dasd_devi
/*
* Request the irq line for the device.
*/
-static int
-dasd_state_known_to_basic(struct dasd_device * device)
+static int dasd_state_known_to_basic(struct dasd_device *device)
{
int rc;
/* Allocate and register gendisk structure. */
- rc = dasd_gendisk_alloc(device);
- if (rc)
- return rc;
-
+ if (device->block) {
+ rc = dasd_gendisk_alloc(device->block);
+ if (rc)
+ return rc;
+ }
/* register 'device' debug area, used for all DBF_DEV_XXX calls */
device->debug_area = debug_register(device->cdev->dev.bus_id, 1, 2,
- 8 * sizeof (long));
+ 8 * sizeof(long));
debug_register_view(device->debug_area, &debug_sprintf_view);
debug_set_level(device->debug_area, DBF_WARNING);
DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
@@ -194,16 +227,17 @@ dasd_state_known_to_basic(struct dasd_de
/*
* Release the irq line for the device. Terminate any running i/o.
*/
-static int
-dasd_state_basic_to_known(struct dasd_device * device)
+static int dasd_state_basic_to_known(struct dasd_device *device)
{
int rc;
-
- dasd_gendisk_free(device);
- rc = dasd_flush_ccw_queue(device, 1);
+ if (device->block) {
+ dasd_gendisk_free(device->block);
+ dasd_block_clear_timer(device->block);
+ }
+ rc = dasd_flush_device_queue(device);
if (rc)
return rc;
- dasd_clear_timer(device);
+ dasd_device_clear_timer(device);
DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
if (device->debug_area != NULL) {
@@ -228,26 +262,32 @@ dasd_state_basic_to_known(struct dasd_de
* In case the analysis returns an error, the device setup is stopped
* (a fake disk was already added to allow formatting).
*/
-static int
-dasd_state_basic_to_ready(struct dasd_device * device)
+static int dasd_state_basic_to_ready(struct dasd_device *device)
{
int rc;
+ struct dasd_block *block;
rc = 0;
- if (device->discipline->do_analysis != NULL)
- rc = device->discipline->do_analysis(device);
- if (rc) {
- if (rc != -EAGAIN)
- device->state = DASD_STATE_UNFMT;
- return rc;
- }
+ block = device->block;
/* make disk known with correct capacity */
- dasd_setup_queue(device);
- set_capacity(device->gdp, device->blocks << device->s2b_shift);
- device->state = DASD_STATE_READY;
- rc = dasd_scan_partitions(device);
- if (rc)
- device->state = DASD_STATE_BASIC;
+ if (block) {
+ if (block->base->discipline->do_analysis != NULL)
+ rc = block->base->discipline->do_analysis(block);
+ if (rc) {
+ if (rc != -EAGAIN)
+ device->state = DASD_STATE_UNFMT;
+ return rc;
+ }
+ dasd_setup_queue(block);
+ set_capacity(block->gdp,
+ block->blocks << block->s2b_shift);
+ device->state = DASD_STATE_READY;
+ rc = dasd_scan_partitions(block);
+ if (rc)
+ device->state = DASD_STATE_BASIC;
+ } else {
+ device->state = DASD_STATE_READY;
+ }
return rc;
}
@@ -256,28 +296,31 @@ dasd_state_basic_to_ready(struct dasd_de
* Forget format information. Check if the target level is basic
* and if it is create fake disk for formatting.
*/
-static int
-dasd_state_ready_to_basic(struct dasd_device * device)
+static int dasd_state_ready_to_basic(struct dasd_device *device)
{
int rc;
- rc = dasd_flush_ccw_queue(device, 0);
- if (rc)
- return rc;
- dasd_destroy_partitions(device);
- dasd_flush_request_queue(device);
- device->blocks = 0;
- device->bp_block = 0;
- device->s2b_shift = 0;
device->state = DASD_STATE_BASIC;
+ if (device->block) {
+ struct dasd_block *block = device->block;
+ rc = dasd_flush_block_queue(block);
+ if (rc) {
+ device->state = DASD_STATE_READY;
+ return rc;
+ }
+ dasd_destroy_partitions(block);
+ dasd_flush_request_queue(block);
+ block->blocks = 0;
+ block->bp_block = 0;
+ block->s2b_shift = 0;
+ }
return 0;
}
/*
* Back to basic.
*/
-static int
-dasd_state_unfmt_to_basic(struct dasd_device * device)
+static int dasd_state_unfmt_to_basic(struct dasd_device *device)
{
device->state = DASD_STATE_BASIC;
return 0;
@@ -291,17 +334,31 @@ dasd_state_unfmt_to_basic(struct dasd_de
static int
dasd_state_ready_to_online(struct dasd_device * device)
{
+ int rc;
+
+ if (device->discipline->ready_to_online) {
+ rc = device->discipline->ready_to_online(device);
+ if (rc)
+ return rc;
+ }
device->state = DASD_STATE_ONLINE;
- dasd_schedule_bh(device);
+ if (device->block)
+ dasd_schedule_block_bh(device->block);
return 0;
}
/*
* Stop the requeueing of requests again.
*/
-static int
-dasd_state_online_to_ready(struct dasd_device * device)
+static int dasd_state_online_to_ready(struct dasd_device *device)
{
+ int rc;
+
+ if (device->discipline->online_to_ready) {
+ rc = device->discipline->online_to_ready(device);
+ if (rc)
+ return rc;
+ }
device->state = DASD_STATE_READY;
return 0;
}
@@ -309,8 +366,7 @@ dasd_state_online_to_ready(struct dasd_d
/*
* Device startup state changes.
*/
-static int
-dasd_increase_state(struct dasd_device *device)
+static int dasd_increase_state(struct dasd_device *device)
{
int rc;
@@ -345,8 +401,7 @@ dasd_increase_state(struct dasd_device *
/*
* Device shutdown state changes.
*/
-static int
-dasd_decrease_state(struct dasd_device *device)
+static int dasd_decrease_state(struct dasd_device *device)
{
int rc;
@@ -381,8 +436,7 @@ dasd_decrease_state(struct dasd_device *
/*
* This is the main startup/shutdown routine.
*/
-static void
-dasd_change_state(struct dasd_device *device)
+static void dasd_change_state(struct dasd_device *device)
{
int rc;
@@ -409,17 +463,15 @@ dasd_change_state(struct dasd_device *de
* dasd_kick_device will schedule a call do do_kick_device to the kernel
* event daemon.
*/
-static void
-do_kick_device(struct work_struct *work)
+static void do_kick_device(struct work_struct *work)
{
struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
dasd_change_state(device);
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
dasd_put_device(device);
}
-void
-dasd_kick_device(struct dasd_device *device)
+void dasd_kick_device(struct dasd_device *device)
{
dasd_get_device(device);
/* queue call to dasd_kick_device to the kernel event daemon. */
@@ -429,8 +481,7 @@ dasd_kick_device(struct dasd_device *dev
/*
* Set the target state for a device and starts the state change.
*/
-void
-dasd_set_target_state(struct dasd_device *device, int target)
+void dasd_set_target_state(struct dasd_device *device, int target)
{
/* If we are in probeonly mode stop at DASD_STATE_READY. */
if (dasd_probeonly && target > DASD_STATE_READY)
@@ -447,14 +498,12 @@ dasd_set_target_state(struct dasd_device
/*
* Enable devices with device numbers in [from..to].
*/
-static inline int
-_wait_for_device(struct dasd_device *device)
+static inline int _wait_for_device(struct dasd_device *device)
{
return (device->state == device->target);
}
-void
-dasd_enable_device(struct dasd_device *device)
+void dasd_enable_device(struct dasd_device *device)
{
dasd_set_target_state(device, DASD_STATE_ONLINE);
if (device->state <= DASD_STATE_KNOWN)
@@ -475,20 +524,20 @@ unsigned int dasd_profile_level = DASD_P
/*
* Increments counter in global and local profiling structures.
*/
-#define dasd_profile_counter(value, counter, device) \
+#define dasd_profile_counter(value, counter, block) \
{ \
int index; \
for (index = 0; index < 31 && value >> (2+index); index++); \
dasd_global_profile.counter[index]++; \
- device->profile.counter[index]++; \
+ block->profile.counter[index]++; \
}
/*
* Add profiling information for cqr before execution.
*/
-static void
-dasd_profile_start(struct dasd_device *device, struct dasd_ccw_req * cqr,
- struct request *req)
+static void dasd_profile_start(struct dasd_block *block,
+ struct dasd_ccw_req *cqr,
+ struct request *req)
{
struct list_head *l;
unsigned int counter;
@@ -498,19 +547,19 @@ dasd_profile_start(struct dasd_device *d
/* count the length of the chanq for statistics */
counter = 0;
- list_for_each(l, &device->ccw_queue)
+ list_for_each(l, &block->ccw_queue)
if (++counter >= 31)
break;
dasd_global_profile.dasd_io_nr_req[counter]++;
- device->profile.dasd_io_nr_req[counter]++;
+ block->profile.dasd_io_nr_req[counter]++;
}
/*
* Add profiling information for cqr after execution.
*/
-static void
-dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
- struct request *req)
+static void dasd_profile_end(struct dasd_block *block,
+ struct dasd_ccw_req *cqr,
+ struct request *req)
{
long strtime, irqtime, endtime, tottime; /* in microseconds */
long tottimeps, sectors;
@@ -532,27 +581,27 @@ dasd_profile_end(struct dasd_device *dev
if (!dasd_global_profile.dasd_io_reqs)
memset(&dasd_global_profile, 0,
- sizeof (struct dasd_profile_info_t));
+ sizeof(struct dasd_profile_info_t));
dasd_global_profile.dasd_io_reqs++;
dasd_global_profile.dasd_io_sects += sectors;
- if (!device->profile.dasd_io_reqs)
- memset(&device->profile, 0,
- sizeof (struct dasd_profile_info_t));
- device->profile.dasd_io_reqs++;
- device->profile.dasd_io_sects += sectors;
-
- dasd_profile_counter(sectors, dasd_io_secs, device);
- dasd_profile_counter(tottime, dasd_io_times, device);
- dasd_profile_counter(tottimeps, dasd_io_timps, device);
- dasd_profile_counter(strtime, dasd_io_time1, device);
- dasd_profile_counter(irqtime, dasd_io_time2, device);
- dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, device);
- dasd_profile_counter(endtime, dasd_io_time3, device);
+ if (!block->profile.dasd_io_reqs)
+ memset(&block->profile, 0,
+ sizeof(struct dasd_profile_info_t));
+ block->profile.dasd_io_reqs++;
+ block->profile.dasd_io_sects += sectors;
+
+ dasd_profile_counter(sectors, dasd_io_secs, block);
+ dasd_profile_counter(tottime, dasd_io_times, block);
+ dasd_profile_counter(tottimeps, dasd_io_timps, block);
+ dasd_profile_counter(strtime, dasd_io_time1, block);
+ dasd_profile_counter(irqtime, dasd_io_time2, block);
+ dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, block);
+ dasd_profile_counter(endtime, dasd_io_time3, block);
}
#else
-#define dasd_profile_start(device, cqr, req) do {} while (0)
-#define dasd_profile_end(device, cqr, req) do {} while (0)
+#define dasd_profile_start(block, cqr, req) do {} while (0)
+#define dasd_profile_end(block, cqr, req) do {} while (0)
#endif /* CONFIG_DASD_PROFILE */
/*
@@ -562,9 +611,9 @@ dasd_profile_end(struct dasd_device *dev
* memory and 2) dasd_smalloc_request uses the static ccw memory
* that gets allocated for each device.
*/
-struct dasd_ccw_req *
-dasd_kmalloc_request(char *magic, int cplength, int datasize,
- struct dasd_device * device)
+struct dasd_ccw_req *dasd_kmalloc_request(char *magic, int cplength,
+ int datasize,
+ struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
@@ -600,9 +649,9 @@ dasd_kmalloc_request(char *magic, int cp
return cqr;
}
-struct dasd_ccw_req *
-dasd_smalloc_request(char *magic, int cplength, int datasize,
- struct dasd_device * device)
+struct dasd_ccw_req *dasd_smalloc_request(char *magic, int cplength,
+ int datasize,
+ struct dasd_device *device)
{
unsigned long flags;
struct dasd_ccw_req *cqr;
@@ -649,8 +698,7 @@ dasd_smalloc_request(char *magic, int cp
* idal lists that might have been created by dasd_set_cda and the
* struct dasd_ccw_req itself.
*/
-void
-dasd_kfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
+void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
{
#ifdef CONFIG_64BIT
struct ccw1 *ccw;
@@ -667,8 +715,7 @@ dasd_kfree_request(struct dasd_ccw_req *
dasd_put_device(device);
}
-void
-dasd_sfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
+void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
{
unsigned long flags;
@@ -681,14 +728,13 @@ dasd_sfree_request(struct dasd_ccw_req *
/*
* Check discipline magic in cqr.
*/
-static inline int
-dasd_check_cqr(struct dasd_ccw_req *cqr)
+static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
if (cqr == NULL)
return -EINVAL;
- device = cqr->device;
+ device = cqr->startdev;
if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
DEV_MESSAGE(KERN_WARNING, device,
" dasd_ccw_req 0x%08x magic doesn't match"
@@ -706,8 +752,7 @@ dasd_check_cqr(struct dasd_ccw_req *cqr)
* ccw_device_clear can fail if the i/o subsystem
* is in a bad mood.
*/
-int
-dasd_term_IO(struct dasd_ccw_req * cqr)
+int dasd_term_IO(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int retries, rc;
@@ -717,13 +762,13 @@ dasd_term_IO(struct dasd_ccw_req * cqr)
if (rc)
return rc;
retries = 0;
- device = (struct dasd_device *) cqr->device;
+ device = (struct dasd_device *) cqr->startdev;
while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
rc = ccw_device_clear(device->cdev, (long) cqr);
switch (rc) {
case 0: /* termination successful */
cqr->retries--;
- cqr->status = DASD_CQR_CLEAR;
+ cqr->status = DASD_CQR_CLEAR_PENDING;
cqr->stopclk = get_clock();
cqr->starttime = 0;
DBF_DEV_EVENT(DBF_DEBUG, device,
@@ -753,7 +798,7 @@ dasd_term_IO(struct dasd_ccw_req * cqr)
}
retries++;
}
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
return rc;
}
@@ -761,8 +806,7 @@ dasd_term_IO(struct dasd_ccw_req * cqr)
* Start the i/o. This start_IO can fail if the channel is really busy.
* In that case set up a timer to start the request later.
*/
-int
-dasd_start_IO(struct dasd_ccw_req * cqr)
+int dasd_start_IO(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int rc;
@@ -771,12 +815,12 @@ dasd_start_IO(struct dasd_ccw_req * cqr)
rc = dasd_check_cqr(cqr);
if (rc)
return rc;
- device = (struct dasd_device *) cqr->device;
+ device = (struct dasd_device *) cqr->startdev;
if (cqr->retries < 0) {
DEV_MESSAGE(KERN_DEBUG, device,
"start_IO: request %p (%02x/%i) - no retry left.",
cqr, cqr->status, cqr->retries);
- cqr->status = DASD_CQR_FAILED;
+ cqr->status = DASD_CQR_ERROR;
return -EIO;
}
cqr->startclk = get_clock();
@@ -833,8 +877,7 @@ dasd_start_IO(struct dasd_ccw_req * cqr)
* The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
* DASD_CQR_QUEUED for 2) and 3).
*/
-static void
-dasd_timeout_device(unsigned long ptr)
+static void dasd_device_timeout(unsigned long ptr)
{
unsigned long flags;
struct dasd_device *device;
@@ -844,14 +887,13 @@ dasd_timeout_device(unsigned long ptr)
/* re-activate request queue */
device->stopped &= ~DASD_STOPPED_PENDING;
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
}
/*
* Setup timeout for a device in jiffies.
*/
-void
-dasd_set_timer(struct dasd_device *device, int expires)
+void dasd_device_set_timer(struct dasd_device *device, int expires)
{
if (expires == 0) {
if (timer_pending(&device->timer))
@@ -862,7 +904,7 @@ dasd_set_timer(struct dasd_device *devic
if (mod_timer(&device->timer, jiffies + expires))
return;
}
- device->timer.function = dasd_timeout_device;
+ device->timer.function = dasd_device_timeout;
device->timer.data = (unsigned long) device;
device->timer.expires = jiffies + expires;
add_timer(&device->timer);
@@ -871,15 +913,14 @@ dasd_set_timer(struct dasd_device *devic
/*
* Clear timeout for a device.
*/
-void
-dasd_clear_timer(struct dasd_device *device)
+void dasd_device_clear_timer(struct dasd_device *device)
{
if (timer_pending(&device->timer))
del_timer(&device->timer);
}
-static void
-dasd_handle_killed_request(struct ccw_device *cdev, unsigned long intparm)
+static void dasd_handle_killed_request(struct ccw_device *cdev,
+ unsigned long intparm)
{
struct dasd_ccw_req *cqr;
struct dasd_device *device;
@@ -893,7 +934,7 @@ dasd_handle_killed_request(struct ccw_de
return;
}
- device = (struct dasd_device *) cqr->device;
+ device = (struct dasd_device *) cqr->startdev;
if (device == NULL ||
device != dasd_device_from_cdev_locked(cdev) ||
strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
@@ -905,13 +946,12 @@ dasd_handle_killed_request(struct ccw_de
/* Schedule request to be retried. */
cqr->status = DASD_CQR_QUEUED;
- dasd_clear_timer(device);
- dasd_schedule_bh(device);
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
dasd_put_device(device);
}
-static void
-dasd_handle_state_change_pending(struct dasd_device *device)
+void dasd_generic_handle_state_change(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
struct list_head *l, *n;
@@ -923,28 +963,27 @@ dasd_handle_state_change_pending(struct
/* restart all 'running' IO on queue */
list_for_each_safe(l, n, &device->ccw_queue) {
- cqr = list_entry(l, struct dasd_ccw_req, list);
+ cqr = list_entry(l, struct dasd_ccw_req, devlist);
if (cqr->status == DASD_CQR_IN_IO) {
cqr->status = DASD_CQR_QUEUED;
}
}
- dasd_clear_timer(device);
- dasd_schedule_bh(device);
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
+ if (device->block)
+ dasd_schedule_block_bh(device->block);
}
/*
* Interrupt handler for "normal" ssch-io based dasd devices.
*/
-void
-dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
- struct irb *irb)
+void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
+ struct irb *irb)
{
struct dasd_ccw_req *cqr, *next;
struct dasd_device *device;
unsigned long long now;
int expires;
- dasd_era_t era;
- char mask;
if (IS_ERR(irb)) {
switch (PTR_ERR(irb)) {
@@ -969,28 +1008,19 @@ dasd_int_handler(struct ccw_device *cdev
cdev->dev.bus_id, ((irb->scsw.cstat<<8)|irb->scsw.dstat),
(unsigned int) intparm);
- /* first of all check for state change pending interrupt */
- mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
- if ((irb->scsw.dstat & mask) == mask) {
+ /* check for unsolicited interrupts */
+ cqr = (struct dasd_ccw_req *) intparm;
+ if (cqr == NULL) {
device = dasd_device_from_cdev_locked(cdev);
if (!IS_ERR(device)) {
- dasd_handle_state_change_pending(device);
+ device->discipline->handle_unsolicited_interrupt(device,
+ irb);
dasd_put_device(device);
}
return;
}
- cqr = (struct dasd_ccw_req *) intparm;
-
- /* check for unsolicited interrupts */
- if (cqr == NULL) {
- MESSAGE(KERN_DEBUG,
- "unsolicited interrupt received: bus_id %s",
- cdev->dev.bus_id);
- return;
- }
-
- device = (struct dasd_device *) cqr->device;
+ device = (struct dasd_device *) cqr->startdev;
if (device == NULL ||
strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
@@ -999,12 +1029,12 @@ dasd_int_handler(struct ccw_device *cdev
}
/* Check for clear pending */
- if (cqr->status == DASD_CQR_CLEAR &&
+ if (cqr->status == DASD_CQR_CLEAR_PENDING &&
irb->scsw.fctl & SCSW_FCTL_CLEAR_FUNC) {
- cqr->status = DASD_CQR_QUEUED;
- dasd_clear_timer(device);
+ cqr->status = DASD_CQR_CLEARED;
+ dasd_device_clear_timer(device);
wake_up(&dasd_flush_wq);
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
return;
}
@@ -1017,272 +1047,164 @@ dasd_int_handler(struct ccw_device *cdev
}
DBF_DEV_EVENT(DBF_DEBUG, device, "Int: CS/DS 0x%04x for cqr %p",
((irb->scsw.cstat << 8) | irb->scsw.dstat), cqr);
-
- /* Find out the appropriate era_action. */
- if (irb->scsw.fctl & SCSW_FCTL_HALT_FUNC)
- era = dasd_era_fatal;
- else if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
- irb->scsw.cstat == 0 &&
- !irb->esw.esw0.erw.cons)
- era = dasd_era_none;
- else if (irb->esw.esw0.erw.cons)
- era = device->discipline->examine_error(cqr, irb);
- else
- era = dasd_era_recover;
-
- DBF_DEV_EVENT(DBF_DEBUG, device, "era_code %d", era);
+ next = NULL;
expires = 0;
- if (era == dasd_era_none) {
- cqr->status = DASD_CQR_DONE;
+ if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
+ irb->scsw.cstat == 0 && !irb->esw.esw0.erw.cons) {
+ /* request was completed successfully */
+ cqr->status = DASD_CQR_SUCCESS;
cqr->stopclk = now;
/* Start first request on queue if possible -> fast_io. */
- if (cqr->list.next != &device->ccw_queue) {
- next = list_entry(cqr->list.next,
- struct dasd_ccw_req, list);
- if ((next->status == DASD_CQR_QUEUED) &&
- (!device->stopped)) {
- if (device->discipline->start_IO(next) == 0)
- expires = next->expires;
- else
- DEV_MESSAGE(KERN_DEBUG, device, "%s",
- "Interrupt fastpath "
- "failed!");
- }
+ if (cqr->devlist.next != &device->ccw_queue) {
+ next = list_entry(cqr->devlist.next,
+ struct dasd_ccw_req, devlist);
}
- } else { /* error */
- memcpy(&cqr->irb, irb, sizeof (struct irb));
+ } else { /* error */
+ memcpy(&cqr->irb, irb, sizeof(struct irb));
if (device->features & DASD_FEATURE_ERPLOG) {
- /* dump sense data */
dasd_log_sense(cqr, irb);
}
- switch (era) {
- case dasd_era_fatal:
- cqr->status = DASD_CQR_FAILED;
- cqr->stopclk = now;
- break;
- case dasd_era_recover:
+ /* If we have no sense data, or we just don't want complex ERP
+ * for this request, but if we have retries left, then just
+ * reset this request and retry it in the fastpath
+ */
+ if (!(cqr->irb.esw.esw0.erw.cons &&
+ test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) &&
+ cqr->retries > 0) {
+ DEV_MESSAGE(KERN_DEBUG, device,
+ "default ERP in fastpath (%i retries left)",
+ cqr->retries);
+ cqr->lpm = LPM_ANYPATH;
+ cqr->status = DASD_CQR_QUEUED;
+ next = cqr;
+ } else
cqr->status = DASD_CQR_ERROR;
- break;
- default:
- BUG();
- }
+ }
+ if (next && (next->status == DASD_CQR_QUEUED) &&
+ (!device->stopped)) {
+ if (device->discipline->start_IO(next) == 0)
+ expires = next->expires;
+ else
+ DEV_MESSAGE(KERN_DEBUG, device, "%s",
+ "Interrupt fastpath "
+ "failed!");
}
if (expires != 0)
- dasd_set_timer(device, expires);
+ dasd_device_set_timer(device, expires);
else
- dasd_clear_timer(device);
- dasd_schedule_bh(device);
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
}
/*
- * posts the buffer_cache about a finalized request
+ * If we have an error on a dasd_block layer request then we cancel
+ * and return all further requests from the same dasd_block as well.
*/
-static inline void
-dasd_end_request(struct request *req, int uptodate)
+static void __dasd_device_recovery(struct dasd_device *device,
+ struct dasd_ccw_req *ref_cqr)
{
- if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
- BUG();
- add_disk_randomness(req->rq_disk);
- end_that_request_last(req, uptodate);
-}
+ struct list_head *l, *n;
+ struct dasd_ccw_req *cqr;
-/*
- * Process finished error recovery ccw.
- */
-static inline void
-__dasd_process_erp(struct dasd_device *device, struct dasd_ccw_req *cqr)
-{
- dasd_erp_fn_t erp_fn;
+ /*
+ * only requeue request that came from the dasd_block layer
+ */
+ if (!ref_cqr->block)
+ return;
- if (cqr->status == DASD_CQR_DONE)
- DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
- else
- DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful");
- erp_fn = device->discipline->erp_postaction(cqr);
- erp_fn(cqr);
-}
+ list_for_each_safe(l, n, &device->ccw_queue) {
+ cqr = list_entry(l, struct dasd_ccw_req, devlist);
+ if (cqr->status == DASD_CQR_QUEUED &&
+ ref_cqr->block == cqr->block) {
+ cqr->status = DASD_CQR_CLEARED;
+ }
+ }
+};
/*
- * Process ccw request queue.
+ * Remove those ccw requests from the queue that need to be returned
+ * to the upper layer.
*/
-static void
-__dasd_process_ccw_queue(struct dasd_device * device,
- struct list_head *final_queue)
+static void __dasd_device_process_ccw_queue(struct dasd_device *device,
+ struct list_head *final_queue)
{
struct list_head *l, *n;
struct dasd_ccw_req *cqr;
- dasd_erp_fn_t erp_fn;
-restart:
/* Process request with final status. */
list_for_each_safe(l, n, &device->ccw_queue) {
- cqr = list_entry(l, struct dasd_ccw_req, list);
+ cqr = list_entry(l, struct dasd_ccw_req, devlist);
+
/* Stop list processing at the first non-final request. */
- if (cqr->status != DASD_CQR_DONE &&
- cqr->status != DASD_CQR_FAILED &&
- cqr->status != DASD_CQR_ERROR)
+ if (cqr->status == DASD_CQR_QUEUED ||
+ cqr->status == DASD_CQR_IN_IO ||
+ cqr->status == DASD_CQR_CLEAR_PENDING)
break;
- /* Process requests with DASD_CQR_ERROR */
if (cqr->status == DASD_CQR_ERROR) {
- if (cqr->irb.scsw.fctl & SCSW_FCTL_HALT_FUNC) {
- cqr->status = DASD_CQR_FAILED;
- cqr->stopclk = get_clock();
- } else {
- if (cqr->irb.esw.esw0.erw.cons &&
- test_bit(DASD_CQR_FLAGS_USE_ERP,
- &cqr->flags)) {
- erp_fn = device->discipline->
- erp_action(cqr);
- erp_fn(cqr);
- } else
- dasd_default_erp_action(cqr);
- }
- goto restart;
- }
-
- /* First of all call extended error reporting. */
- if (dasd_eer_enabled(device) &&
- cqr->status == DASD_CQR_FAILED) {
- dasd_eer_write(device, cqr, DASD_EER_FATALERROR);
-
- /* restart request */
- cqr->status = DASD_CQR_QUEUED;
- cqr->retries = 255;
- device->stopped |= DASD_STOPPED_QUIESCE;
- goto restart;
- }
-
- /* Process finished ERP request. */
- if (cqr->refers) {
- __dasd_process_erp(device, cqr);
- goto restart;
+ __dasd_device_recovery(device, cqr);
}
-
/* Rechain finished requests to final queue */
- cqr->endclk = get_clock();
- list_move_tail(&cqr->list, final_queue);
+ list_move_tail(&cqr->devlist, final_queue);
}
}
-static void
-dasd_end_request_cb(struct dasd_ccw_req * cqr, void *data)
-{
- struct request *req;
- struct dasd_device *device;
- int status;
-
- req = (struct request *) data;
- device = cqr->device;
- dasd_profile_end(device, cqr, req);
- status = cqr->device->discipline->free_cp(cqr,req);
- spin_lock_irq(&device->request_queue_lock);
- dasd_end_request(req, status);
- spin_unlock_irq(&device->request_queue_lock);
-}
-
-
/*
- * Fetch requests from the block device queue.
+ * the cqrs from the final queue are returned to the upper layer
+ * by setting a dasd_block state and calling the callback function
*/
-static void
-__dasd_process_blk_queue(struct dasd_device * device)
+static void __dasd_device_process_final_queue(struct dasd_device *device,
+ struct list_head *final_queue)
{
- struct request_queue *queue;
- struct request *req;
+ struct list_head *l, *n;
struct dasd_ccw_req *cqr;
- int nr_queued;
-
- queue = device->request_queue;
- /* No queue ? Then there is nothing to do. */
- if (queue == NULL)
- return;
-
- /*
- * We requeue request from the block device queue to the ccw
- * queue only in two states. In state DASD_STATE_READY the
- * partition detection is done and we need to requeue requests
- * for that. State DASD_STATE_ONLINE is normal block device
- * operation.
- */
- if (device->state != DASD_STATE_READY &&
- device->state != DASD_STATE_ONLINE)
- return;
- nr_queued = 0;
- /* Now we try to fetch requests from the request queue */
- list_for_each_entry(cqr, &device->ccw_queue, list)
- if (cqr->status == DASD_CQR_QUEUED)
- nr_queued++;
- while (!blk_queue_plugged(queue) &&
- elv_next_request(queue) &&
- nr_queued < DASD_CHANQ_MAX_SIZE) {
- req = elv_next_request(queue);
- if (device->features & DASD_FEATURE_READONLY &&
- rq_data_dir(req) == WRITE) {
- DBF_DEV_EVENT(DBF_ERR, device,
- "Rejecting write request %p",
- req);
- blkdev_dequeue_request(req);
- dasd_end_request(req, 0);
- continue;
- }
- if (device->stopped & DASD_STOPPED_DC_EIO) {
- blkdev_dequeue_request(req);
- dasd_end_request(req, 0);
- continue;
- }
- cqr = device->discipline->build_cp(device, req);
- if (IS_ERR(cqr)) {
- if (PTR_ERR(cqr) == -ENOMEM)
- break; /* terminate request queue loop */
- if (PTR_ERR(cqr) == -EAGAIN) {
- /*
- * The current request cannot be build right
- * now, we have to try later. If this request
- * is the head-of-queue we stop the device
- * for 1/2 second.
- */
- if (!list_empty(&device->ccw_queue))
- break;
- device->stopped |= DASD_STOPPED_PENDING;
- dasd_set_timer(device, HZ/2);
- break;
- }
- DBF_DEV_EVENT(DBF_ERR, device,
- "CCW creation failed (rc=%ld) "
- "on request %p",
- PTR_ERR(cqr), req);
- blkdev_dequeue_request(req);
- dasd_end_request(req, 0);
- continue;
+ list_for_each_safe(l, n, final_queue) {
+ cqr = list_entry(l, struct dasd_ccw_req, devlist);
+ list_del_init(&cqr->devlist);
+ if (cqr->block)
+ spin_lock_bh(&cqr->block->queue_lock);
+ switch (cqr->status) {
+ case DASD_CQR_SUCCESS:
+ cqr->status = DASD_CQR_DONE;
+ break;
+ case DASD_CQR_ERROR:
+ cqr->status = DASD_CQR_NEED_ERP;
+ break;
+ case DASD_CQR_CLEARED:
+ cqr->status = DASD_CQR_TERMINATED;
+ break;
+ default:
+ DEV_MESSAGE(KERN_ERR, device,
+ "wrong cqr status in __dasd_process_final_queue "
+ "for cqr %p, status %x",
+ cqr, cqr->status);
+ BUG();
}
- cqr->callback = dasd_end_request_cb;
- cqr->callback_data = (void *) req;
- cqr->status = DASD_CQR_QUEUED;
- blkdev_dequeue_request(req);
- list_add_tail(&cqr->list, &device->ccw_queue);
- dasd_profile_start(device, cqr, req);
- nr_queued++;
+ if (cqr->block)
+ spin_unlock_bh(&cqr->block->queue_lock);
+ if (cqr->callback != NULL)
+ (cqr->callback)(cqr, cqr->callback_data);
}
}
+
+
/*
* Take a look at the first request on the ccw queue and check
* if it reached its expire time. If so, terminate the IO.
*/
-static void
-__dasd_check_expire(struct dasd_device * device)
+static void __dasd_device_check_expire(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
if (list_empty(&device->ccw_queue))
return;
- cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
+ cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
(time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
if (device->discipline->term_IO(cqr) != 0) {
/* Hmpf, try again in 5 sec */
- dasd_set_timer(device, 5*HZ);
+ dasd_device_set_timer(device, 5*HZ);
DEV_MESSAGE(KERN_ERR, device,
"internal error - timeout (%is) expired "
"for cqr %p, termination failed, "
@@ -1301,77 +1223,53 @@ __dasd_check_expire(struct dasd_device *
* Take a look at the first request on the ccw queue and check
* if it needs to be started.
*/
-static void
-__dasd_start_head(struct dasd_device * device)
+static void __dasd_device_start_head(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
int rc;
if (list_empty(&device->ccw_queue))
return;
- cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
+ cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
if (cqr->status != DASD_CQR_QUEUED)
return;
- /* Non-temporary stop condition will trigger fail fast */
- if (device->stopped & ~DASD_STOPPED_PENDING &&
- test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
- (!dasd_eer_enabled(device))) {
- cqr->status = DASD_CQR_FAILED;
- dasd_schedule_bh(device);
+ /* when device is stopped, return request to previous layer */
+ if (device->stopped) {
+ cqr->status = DASD_CQR_CLEARED;
+ dasd_schedule_device_bh(device);
return;
}
- /* Don't try to start requests if device is stopped */
- if (device->stopped)
- return;
rc = device->discipline->start_IO(cqr);
if (rc == 0)
- dasd_set_timer(device, cqr->expires);
+ dasd_device_set_timer(device, cqr->expires);
else if (rc == -EACCES) {
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
} else
/* Hmpf, try again in 1/2 sec */
- dasd_set_timer(device, 50);
-}
-
-static inline int
-_wait_for_clear(struct dasd_ccw_req *cqr)
-{
- return (cqr->status == DASD_CQR_QUEUED);
+ dasd_device_set_timer(device, 50);
}
/*
- * Remove all requests from the ccw queue (all = '1') or only block device
- * requests in case all = '0'.
- * Take care of the erp-chain (chained via cqr->refers) and remove either
- * the whole erp-chain or none of the erp-requests.
- * If a request is currently running, term_IO is called and the request
- * is re-queued. Prior to removing the terminated request we need to wait
- * for the clear-interrupt.
- * In case termination is not possible we stop processing and just finishing
- * the already moved requests.
+ * Go through all request on the dasd_device request queue,
+ * terminate them on the cdev if necessary, and return them to the
+ * submitting layer via callback.
+ * Note:
+ * Make sure that all 'submitting layers' still exist when
+ * this function is called!. In other words, when 'device' is a base
+ * device then all block layer requests must have been removed before
+ * via dasd_flush_block_queue.
*/
-static int
-dasd_flush_ccw_queue(struct dasd_device * device, int all)
+int dasd_flush_device_queue(struct dasd_device *device)
{
- struct dasd_ccw_req *cqr, *orig, *n;
- int rc, i;
-
+ struct dasd_ccw_req *cqr, *n;
+ int rc;
struct list_head flush_queue;
INIT_LIST_HEAD(&flush_queue);
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = 0;
-restart:
- list_for_each_entry_safe(cqr, n, &device->ccw_queue, list) {
- /* get original request of erp request-chain */
- for (orig = cqr; orig->refers != NULL; orig = orig->refers);
-
- /* Flush all request or only block device requests? */
- if (all == 0 && cqr->callback != dasd_end_request_cb &&
- orig->callback != dasd_end_request_cb) {
- continue;
- }
+ list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
/* Check status and move request to flush_queue */
switch (cqr->status) {
case DASD_CQR_IN_IO:
@@ -1387,90 +1285,60 @@ restart:
}
break;
case DASD_CQR_QUEUED:
- case DASD_CQR_ERROR:
- /* set request to FAILED */
cqr->stopclk = get_clock();
- cqr->status = DASD_CQR_FAILED;
+ cqr->status = DASD_CQR_CLEARED;
break;
- default: /* do not touch the others */
+ default: /* no need to modify the others */
break;
}
- /* Rechain request (including erp chain) */
- for (i = 0; cqr != NULL; cqr = cqr->refers, i++) {
- cqr->endclk = get_clock();
- list_move_tail(&cqr->list, &flush_queue);
- }
- if (i > 1)
- /* moved more than one request - need to restart */
- goto restart;
+ list_move_tail(&cqr->devlist, &flush_queue);
}
-
finished:
spin_unlock_irq(get_ccwdev_lock(device->cdev));
- /* Now call the callback function of flushed requests */
-restart_cb:
- list_for_each_entry_safe(cqr, n, &flush_queue, list) {
- if (cqr->status == DASD_CQR_CLEAR) {
- /* wait for clear interrupt! */
- wait_event(dasd_flush_wq, _wait_for_clear(cqr));
- cqr->status = DASD_CQR_FAILED;
- }
- /* Process finished ERP request. */
- if (cqr->refers) {
- __dasd_process_erp(device, cqr);
- /* restart list_for_xx loop since dasd_process_erp
- * might remove multiple elements */
- goto restart_cb;
- }
- /* call the callback function */
- cqr->endclk = get_clock();
- if (cqr->callback != NULL)
- (cqr->callback)(cqr, cqr->callback_data);
- }
+ /*
+ * After this point all requests must be in state CLEAR_PENDING,
+ * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
+ * one of the others.
+ */
+ list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
+ wait_event(dasd_flush_wq,
+ (cqr->status != DASD_CQR_CLEAR_PENDING));
+ /*
+ * Now set each request back to TERMINATED, DONE or NEED_ERP
+ * and call the callback function of flushed requests
+ */
+ __dasd_device_process_final_queue(device, &flush_queue);
return rc;
}
/*
* Acquire the device lock and process queues for the device.
*/
-static void
-dasd_tasklet(struct dasd_device * device)
+static void dasd_device_tasklet(struct dasd_device *device)
{
struct list_head final_queue;
- struct list_head *l, *n;
- struct dasd_ccw_req *cqr;
atomic_set (&device->tasklet_scheduled, 0);
INIT_LIST_HEAD(&final_queue);
spin_lock_irq(get_ccwdev_lock(device->cdev));
/* Check expire time of first request on the ccw queue. */
- __dasd_check_expire(device);
- /* Finish off requests on ccw queue */
- __dasd_process_ccw_queue(device, &final_queue);
+ __dasd_device_check_expire(device);
+ /* find final requests on ccw queue */
+ __dasd_device_process_ccw_queue(device, &final_queue);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
/* Now call the callback function of requests with final status */
- list_for_each_safe(l, n, &final_queue) {
- cqr = list_entry(l, struct dasd_ccw_req, list);
- list_del_init(&cqr->list);
- if (cqr->callback != NULL)
- (cqr->callback)(cqr, cqr->callback_data);
- }
- spin_lock_irq(&device->request_queue_lock);
- spin_lock(get_ccwdev_lock(device->cdev));
- /* Get new request from the block device request queue */
- __dasd_process_blk_queue(device);
+ __dasd_device_process_final_queue(device, &final_queue);
+ spin_lock_irq(get_ccwdev_lock(device->cdev));
/* Now check if the head of the ccw queue needs to be started. */
- __dasd_start_head(device);
- spin_unlock(get_ccwdev_lock(device->cdev));
- spin_unlock_irq(&device->request_queue_lock);
+ __dasd_device_start_head(device);
+ spin_unlock_irq(get_ccwdev_lock(device->cdev));
dasd_put_device(device);
}
/*
* Schedules a call to dasd_tasklet over the device tasklet.
*/
-void
-dasd_schedule_bh(struct dasd_device * device)
+void dasd_schedule_device_bh(struct dasd_device *device)
{
/* Protect against rescheduling. */
if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
@@ -1480,160 +1348,109 @@ dasd_schedule_bh(struct dasd_device * de
}
/*
- * Queue a request to the head of the ccw_queue. Start the I/O if
- * possible.
+ * Queue a request to the head of the device ccw_queue.
+ * Start the I/O if possible.
*/
-void
-dasd_add_request_head(struct dasd_ccw_req *req)
+void dasd_add_request_head(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
unsigned long flags;
- device = req->device;
+ device = cqr->startdev;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
- req->status = DASD_CQR_QUEUED;
- req->device = device;
- list_add(&req->list, &device->ccw_queue);
+ cqr->status = DASD_CQR_QUEUED;
+ list_add(&cqr->devlist, &device->ccw_queue);
/* let the bh start the request to keep them in order */
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
}
/*
- * Queue a request to the tail of the ccw_queue. Start the I/O if
- * possible.
+ * Queue a request to the tail of the device ccw_queue.
+ * Start the I/O if possible.
*/
-void
-dasd_add_request_tail(struct dasd_ccw_req *req)
+void dasd_add_request_tail(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
unsigned long flags;
- device = req->device;
+ device = cqr->startdev;
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
- req->status = DASD_CQR_QUEUED;
- req->device = device;
- list_add_tail(&req->list, &device->ccw_queue);
+ cqr->status = DASD_CQR_QUEUED;
+ list_add_tail(&cqr->devlist, &device->ccw_queue);
/* let the bh start the request to keep them in order */
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
}
/*
- * Wakeup callback.
+ * Wakeup helper for the 'sleep_on' functions.
*/
-static void
-dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
+static void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
{
wake_up((wait_queue_head_t *) data);
}
-static inline int
-_wait_for_wakeup(struct dasd_ccw_req *cqr)
+static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
int rc;
- device = cqr->device;
+ device = cqr->startdev;
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = ((cqr->status == DASD_CQR_DONE ||
- cqr->status == DASD_CQR_FAILED) &&
- list_empty(&cqr->list));
+ cqr->status == DASD_CQR_NEED_ERP ||
+ cqr->status == DASD_CQR_TERMINATED) &&
+ list_empty(&cqr->devlist));
spin_unlock_irq(get_ccwdev_lock(device->cdev));
return rc;
}
/*
- * Attempts to start a special ccw queue and waits for its completion.
+ * Queue a request to the tail of the device ccw_queue and wait for
+ * it's completion.
*/
-int
-dasd_sleep_on(struct dasd_ccw_req * cqr)
+int dasd_sleep_on(struct dasd_ccw_req *cqr)
{
wait_queue_head_t wait_q;
struct dasd_device *device;
int rc;
- device = cqr->device;
- spin_lock_irq(get_ccwdev_lock(device->cdev));
+ device = cqr->startdev;
init_waitqueue_head (&wait_q);
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = (void *) &wait_q;
- cqr->status = DASD_CQR_QUEUED;
- list_add_tail(&cqr->list, &device->ccw_queue);
-
- /* let the bh start the request to keep them in order */
- dasd_schedule_bh(device);
-
- spin_unlock_irq(get_ccwdev_lock(device->cdev));
-
+ dasd_add_request_tail(cqr);
wait_event(wait_q, _wait_for_wakeup(cqr));
/* Request status is either done or failed. */
- rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
+ rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO;
return rc;
}
/*
- * Attempts to start a special ccw queue and wait interruptible
- * for its completion.
+ * Queue a request to the tail of the device ccw_queue and wait
+ * interruptible for it's completion.
*/
-int
-dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)
+int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
{
wait_queue_head_t wait_q;
struct dasd_device *device;
- int rc, finished;
-
- device = cqr->device;
- spin_lock_irq(get_ccwdev_lock(device->cdev));
+ int rc;
+ device = cqr->startdev;
init_waitqueue_head (&wait_q);
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = (void *) &wait_q;
- cqr->status = DASD_CQR_QUEUED;
- list_add_tail(&cqr->list, &device->ccw_queue);
-
- /* let the bh start the request to keep them in order */
- dasd_schedule_bh(device);
- spin_unlock_irq(get_ccwdev_lock(device->cdev));
-
- finished = 0;
- while (!finished) {
- rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr));
- if (rc != -ERESTARTSYS) {
- /* Request is final (done or failed) */
- rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO;
- break;
- }
- spin_lock_irq(get_ccwdev_lock(device->cdev));
- switch (cqr->status) {
- case DASD_CQR_IN_IO:
- /* terminate runnig cqr */
- if (device->discipline->term_IO) {
- cqr->retries = -1;
- device->discipline->term_IO(cqr);
- /* wait (non-interruptible) for final status
- * because signal ist still pending */
- spin_unlock_irq(get_ccwdev_lock(device->cdev));
- wait_event(wait_q, _wait_for_wakeup(cqr));
- spin_lock_irq(get_ccwdev_lock(device->cdev));
- rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO;
- finished = 1;
- }
- break;
- case DASD_CQR_QUEUED:
- /* request */
- list_del_init(&cqr->list);
- rc = -EIO;
- finished = 1;
- break;
- default:
- /* cqr with 'non-interruptable' status - just wait */
- break;
- }
- spin_unlock_irq(get_ccwdev_lock(device->cdev));
+ dasd_add_request_tail(cqr);
+ rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr));
+ if (rc == -ERESTARTSYS) {
+ dasd_cancel_req(cqr);
+ /* wait (non-interruptible) for final status */
+ wait_event(wait_q, _wait_for_wakeup(cqr));
}
+ rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO;
return rc;
}
@@ -1643,25 +1460,23 @@ dasd_sleep_on_interruptible(struct dasd_
* and be put back to status queued, before the special request is added
* to the head of the queue. Then the special request is waited on normally.
*/
-static inline int
-_dasd_term_running_cqr(struct dasd_device *device)
+static inline int _dasd_term_running_cqr(struct dasd_device *device)
{
struct dasd_ccw_req *cqr;
if (list_empty(&device->ccw_queue))
return 0;
- cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
+ cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
return device->discipline->term_IO(cqr);
}
-int
-dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)
+int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
{
wait_queue_head_t wait_q;
struct dasd_device *device;
int rc;
- device = cqr->device;
+ device = cqr->startdev;
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = _dasd_term_running_cqr(device);
if (rc) {
@@ -1673,17 +1488,17 @@ dasd_sleep_on_immediatly(struct dasd_ccw
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = (void *) &wait_q;
cqr->status = DASD_CQR_QUEUED;
- list_add(&cqr->list, &device->ccw_queue);
+ list_add(&cqr->devlist, &device->ccw_queue);
/* let the bh start the request to keep them in order */
- dasd_schedule_bh(device);
+ dasd_schedule_device_bh(device);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
wait_event(wait_q, _wait_for_wakeup(cqr));
/* Request status is either done or failed. */
- rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
+ rc = (cqr->status == DASD_CQR_DONE) ? 0 : -EIO;
return rc;
}
@@ -1692,11 +1507,14 @@ dasd_sleep_on_immediatly(struct dasd_ccw
* This is useful to timeout requests. The request will be
* terminated if it is currently in i/o.
* Returns 1 if the request has been terminated.
+ * 0 if there was no need to terminate the request (not started yet)
+ * negative error code if termination failed
+ * Cancellation of a request is an asynchronous operation! The calling
+ * function has to wait until the request is properly returned via callback.
*/
-int
-dasd_cancel_req(struct dasd_ccw_req *cqr)
+int dasd_cancel_req(struct dasd_ccw_req *cqr)
{
- struct dasd_device *device = cqr->device;
+ struct dasd_device *device = cqr->startdev;
unsigned long flags;
int rc;
@@ -1704,74 +1522,453 @@ dasd_cancel_req(struct dasd_ccw_req *cqr
spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
switch (cqr->status) {
case DASD_CQR_QUEUED:
- /* request was not started - just set to failed */
- cqr->status = DASD_CQR_FAILED;
+ /* request was not started - just set to cleared */
+ cqr->status = DASD_CQR_CLEARED;
break;
case DASD_CQR_IN_IO:
/* request in IO - terminate IO and release again */
- if (device->discipline->term_IO(cqr) != 0)
- /* what to do if unable to terminate ??????
- e.g. not _IN_IO */
- cqr->status = DASD_CQR_FAILED;
- cqr->stopclk = get_clock();
- rc = 1;
+ rc = device->discipline->term_IO(cqr);
+ if (rc) {
+ DEV_MESSAGE(KERN_ERR, device,
+ "dasd_cancel_req is unable "
+ " to terminate request %p, rc = %d",
+ cqr, rc);
+ } else {
+ cqr->stopclk = get_clock();
+ rc = 1;
+ }
break;
- case DASD_CQR_DONE:
- case DASD_CQR_FAILED:
- /* already finished - do nothing */
+ default: /* already finished or clear pending - do nothing */
break;
- default:
- DEV_MESSAGE(KERN_ALERT, device,
- "invalid status %02x in request",
- cqr->status);
+ }
+ spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+ dasd_schedule_device_bh(device);
+ return rc;
+}
+
+
+/*
+ * SECTION: Operations of the dasd_block layer.
+ */
+
+/*
+ * Timeout function for dasd_block. This is used when the block layer
+ * is waiting for something that may not come reliably, (e.g. a state
+ * change interrupt)
+ */
+static void dasd_block_timeout(unsigned long ptr)
+{
+ unsigned long flags;
+ struct dasd_block *block;
+
+ block = (struct dasd_block *) ptr;
+ spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
+ /* re-activate request queue */
+ block->base->stopped &= ~DASD_STOPPED_PENDING;
+ spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
+ dasd_schedule_block_bh(block);
+}
+
+/*
+ * Setup timeout for a dasd_block in jiffies.
+ */
+void dasd_block_set_timer(struct dasd_block *block, int expires)
+{
+ if (expires == 0) {
+ if (timer_pending(&block->timer))
+ del_timer(&block->timer);
+ return;
+ }
+ if (timer_pending(&block->timer)) {
+ if (mod_timer(&block->timer, jiffies + expires))
+ return;
+ }
+ block->timer.function = dasd_block_timeout;
+ block->timer.data = (unsigned long) block;
+ block->timer.expires = jiffies + expires;
+ add_timer(&block->timer);
+}
+
+/*
+ * Clear timeout for a dasd_block.
+ */
+void dasd_block_clear_timer(struct dasd_block *block)
+{
+ if (timer_pending(&block->timer))
+ del_timer(&block->timer);
+}
+
+/*
+ * posts the buffer_cache about a finalized request
+ */
+static inline void dasd_end_request(struct request *req, int uptodate)
+{
+ if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
BUG();
+ add_disk_randomness(req->rq_disk);
+ end_that_request_last(req, uptodate);
+}
+
+/*
+ * Process finished error recovery ccw.
+ */
+static inline void __dasd_block_process_erp(struct dasd_block *block,
+ struct dasd_ccw_req *cqr)
+{
+ dasd_erp_fn_t erp_fn;
+ struct dasd_device *device = block->base;
+
+ if (cqr->status == DASD_CQR_DONE)
+ DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
+ else
+ DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful");
+ erp_fn = device->discipline->erp_postaction(cqr);
+ erp_fn(cqr);
+}
+
+/*
+ * Fetch requests from the block device queue.
+ */
+static void __dasd_process_request_queue(struct dasd_block *block)
+{
+ struct request_queue *queue;
+ struct request *req;
+ struct dasd_ccw_req *cqr;
+ struct dasd_device *basedev;
+ unsigned long flags;
+ queue = block->request_queue;
+ basedev = block->base;
+ /* No queue ? Then there is nothing to do. */
+ if (queue == NULL)
+ return;
+
+ /*
+ * We requeue request from the block device queue to the ccw
+ * queue only in two states. In state DASD_STATE_READY the
+ * partition detection is done and we need to requeue requests
+ * for that. State DASD_STATE_ONLINE is normal block device
+ * operation.
+ */
+ if (basedev->state < DASD_STATE_READY)
+ return;
+ /* Now we try to fetch requests from the request queue */
+ while (!blk_queue_plugged(queue) &&
+ elv_next_request(queue)) {
+
+ req = elv_next_request(queue);
+
+ if (basedev->features & DASD_FEATURE_READONLY &&
+ rq_data_dir(req) == WRITE) {
+ DBF_DEV_EVENT(DBF_ERR, basedev,
+ "Rejecting write request %p",
+ req);
+ blkdev_dequeue_request(req);
+ dasd_end_request(req, 0);
+ continue;
+ }
+ cqr = basedev->discipline->build_cp(basedev, block, req);
+ if (IS_ERR(cqr)) {
+ if (PTR_ERR(cqr) == -EBUSY)
+ break; /* normal end condition */
+ if (PTR_ERR(cqr) == -ENOMEM)
+ break; /* terminate request queue loop */
+ if (PTR_ERR(cqr) == -EAGAIN) {
+ /*
+ * The current request cannot be build right
+ * now, we have to try later. If this request
+ * is the head-of-queue we stop the device
+ * for 1/2 second.
+ */
+ if (!list_empty(&block->ccw_queue))
+ break;
+ spin_lock_irqsave(get_ccwdev_lock(basedev->cdev), flags);
+ basedev->stopped |= DASD_STOPPED_PENDING;
+ spin_unlock_irqrestore(get_ccwdev_lock(basedev->cdev), flags);
+ dasd_block_set_timer(block, HZ/2);
+ break;
+ }
+ DBF_DEV_EVENT(DBF_ERR, basedev,
+ "CCW creation failed (rc=%ld) "
+ "on request %p",
+ PTR_ERR(cqr), req);
+ blkdev_dequeue_request(req);
+ dasd_end_request(req, 0);
+ continue;
+ }
+ /*
+ * Note: callback is set to dasd_return_cqr_cb in
+ * __dasd_block_start_head to cover erp requests as well
+ */
+ cqr->callback_data = (void *) req;
+ cqr->status = DASD_CQR_FILLED;
+ blkdev_dequeue_request(req);
+ list_add_tail(&cqr->blocklist, &block->ccw_queue);
+ dasd_profile_start(block, cqr, req);
+ }
+}
+
+static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
+{
+ struct request *req;
+ int status;
+
+ req = (struct request *) cqr->callback_data;
+ dasd_profile_end(cqr->block, cqr, req);
+ status = cqr->memdev->discipline->free_cp(cqr, req);
+ dasd_end_request(req, status);
+}
+
+/*
+ * Process ccw request queue.
+ */
+static void __dasd_process_block_ccw_queue(struct dasd_block *block,
+ struct list_head *final_queue)
+{
+ struct list_head *l, *n;
+ struct dasd_ccw_req *cqr;
+ dasd_erp_fn_t erp_fn;
+ unsigned long flags;
+ struct dasd_device *base = block->base;
+
+restart:
+ /* Process request with final status. */
+ list_for_each_safe(l, n, &block->ccw_queue) {
+ cqr = list_entry(l, struct dasd_ccw_req, blocklist);
+ if (cqr->status != DASD_CQR_DONE &&
+ cqr->status != DASD_CQR_FAILED &&
+ cqr->status != DASD_CQR_NEED_ERP &&
+ cqr->status != DASD_CQR_TERMINATED)
+ continue;
+
+ if (cqr->status == DASD_CQR_TERMINATED) {
+ base->discipline->handle_terminated_request(cqr);
+ goto restart;
+ }
+
+ /* Process requests that may be recovered */
+ if (cqr->status == DASD_CQR_NEED_ERP) {
+ if (cqr->irb.esw.esw0.erw.cons &&
+ test_bit(DASD_CQR_FLAGS_USE_ERP,
+ &cqr->flags)) {
+ erp_fn = base->discipline->erp_action(cqr);
+ erp_fn(cqr);
+ }
+ goto restart;
+ }
+
+ /* First of all call extended error reporting. */
+ if (dasd_eer_enabled(base) &&
+ cqr->status == DASD_CQR_FAILED) {
+ dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
+
+ /* restart request */
+ cqr->status = DASD_CQR_FILLED;
+ cqr->retries = 255;
+ spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
+ base->stopped |= DASD_STOPPED_QUIESCE;
+ spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
+ flags);
+ goto restart;
+ }
+ /* Process finished ERP request. */
+ if (cqr->refers) {
+ __dasd_block_process_erp(block, cqr);
+ goto restart;
+ }
+
+ /* Rechain finished requests to final queue */
+ cqr->endclk = get_clock();
+ list_move_tail(&cqr->blocklist, final_queue);
+ }
+}
+
+static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
+{
+ dasd_schedule_block_bh(cqr->block);
+}
+
+static void __dasd_block_start_head(struct dasd_block *block)
+{
+ struct dasd_ccw_req *cqr;
+
+ if (list_empty(&block->ccw_queue))
+ return;
+ /* We allways begin with the first requests on the queue, as some
+ * of previously started requests have to be enqueued on a
+ * dasd_device again for error recovery.
+ */
+ list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
+ if (cqr->status != DASD_CQR_FILLED)
+ continue;
+ /* Non-temporary stop condition will trigger fail fast */
+ if (block->base->stopped & ~DASD_STOPPED_PENDING &&
+ test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
+ (!dasd_eer_enabled(block->base))) {
+ cqr->status = DASD_CQR_FAILED;
+ dasd_schedule_block_bh(block);
+ continue;
+ }
+ /* Don't try to start requests if device is stopped */
+ if (block->base->stopped)
+ return;
+
+ /* just a fail safe check, should not happen */
+ if (!cqr->startdev)
+ cqr->startdev = block->base;
+
+ /* make sure that the requests we submit find their way back */
+ cqr->callback = dasd_return_cqr_cb;
+
+ dasd_add_request_tail(cqr);
+ }
+}
+
+/*
+ * Central dasd_block layer routine. Takes requests from the generic
+ * block layer request queue, creates ccw requests, enqueues them on
+ * a dasd_device and processes ccw requests that have been returned.
+ */
+static void dasd_block_tasklet(struct dasd_block *block)
+{
+ struct list_head final_queue;
+ struct list_head *l, *n;
+ struct dasd_ccw_req *cqr;
+
+ atomic_set(&block->tasklet_scheduled, 0);
+ INIT_LIST_HEAD(&final_queue);
+ spin_lock(&block->queue_lock);
+ /* Finish off requests on ccw queue */
+ __dasd_process_block_ccw_queue(block, &final_queue);
+ spin_unlock(&block->queue_lock);
+ /* Now call the callback function of requests with final status */
+ spin_lock_irq(&block->request_queue_lock);
+ list_for_each_safe(l, n, &final_queue) {
+ cqr = list_entry(l, struct dasd_ccw_req, blocklist);
+ list_del_init(&cqr->blocklist);
+ __dasd_cleanup_cqr(cqr);
+ }
+ spin_lock(&block->queue_lock);
+ /* Get new request from the block device request queue */
+ __dasd_process_request_queue(block);
+ /* Now check if the head of the ccw queue needs to be started. */
+ __dasd_block_start_head(block);
+ spin_unlock(&block->queue_lock);
+ spin_unlock_irq(&block->request_queue_lock);
+ dasd_put_device(block->base);
+}
+
+static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
+{
+ wake_up(&dasd_flush_wq);
+}
+
+/*
+ * Go through all request on the dasd_block request queue, cancel them
+ * on the respective dasd_device, and return them to the generic
+ * block layer.
+ */
+static int dasd_flush_block_queue(struct dasd_block *block)
+{
+ struct dasd_ccw_req *cqr, *n;
+ int rc, i;
+ struct list_head flush_queue;
+
+ INIT_LIST_HEAD(&flush_queue);
+ spin_lock_bh(&block->queue_lock);
+ rc = 0;
+restart:
+ list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
+ /* if this request currently owned by a dasd_device cancel it */
+ if (cqr->status >= DASD_CQR_QUEUED)
+ rc = dasd_cancel_req(cqr);
+ if (rc < 0)
+ break;
+ /* Rechain request (including erp chain) so it won't be
+ * touched by the dasd_block_tasklet anymore.
+ * Replace the callback so we notice when the request
+ * is returned from the dasd_device layer.
+ */
+ cqr->callback = _dasd_wake_block_flush_cb;
+ for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
+ list_move_tail(&cqr->blocklist, &flush_queue);
+ if (i > 1)
+ /* moved more than one request - need to restart */
+ goto restart;
+ }
+ spin_unlock_bh(&block->queue_lock);
+ /* Now call the callback function of flushed requests */
+restart_cb:
+ list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
+ wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
+ /* Process finished ERP request. */
+ if (cqr->refers) {
+ __dasd_block_process_erp(block, cqr);
+ /* restart list_for_xx loop since dasd_process_erp
+ * might remove multiple elements */
+ goto restart_cb;
+ }
+ /* call the callback function */
+ cqr->endclk = get_clock();
+ list_del_init(&cqr->blocklist);
+ __dasd_cleanup_cqr(cqr);
}
- spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
- dasd_schedule_bh(device);
return rc;
}
/*
- * SECTION: Block device operations (request queue, partitions, open, release).
+ * Schedules a call to dasd_tasklet over the device tasklet.
+ */
+void dasd_schedule_block_bh(struct dasd_block *block)
+{
+ /* Protect against rescheduling. */
+ if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
+ return;
+ /* life cycle of block is bound to it's base device */
+ dasd_get_device(block->base);
+ tasklet_hi_schedule(&block->tasklet);
+}
+
+
+/*
+ * SECTION: external block device operations
+ * (request queue handling, open, release, etc.)
*/
/*
* Dasd request queue function. Called from ll_rw_blk.c
*/
-static void
-do_dasd_request(struct request_queue * queue)
+static void do_dasd_request(struct request_queue *queue)
{
- struct dasd_device *device;
+ struct dasd_block *block;
- device = (struct dasd_device *) queue->queuedata;
- spin_lock(get_ccwdev_lock(device->cdev));
+ block = queue->queuedata;
+ spin_lock(&block->queue_lock);
/* Get new request from the block device request queue */
- __dasd_process_blk_queue(device);
+ __dasd_process_request_queue(block);
/* Now check if the head of the ccw queue needs to be started. */
- __dasd_start_head(device);
- spin_unlock(get_ccwdev_lock(device->cdev));
+ __dasd_block_start_head(block);
+ spin_unlock(&block->queue_lock);
}
/*
* Allocate and initialize request queue and default I/O scheduler.
*/
-static int
-dasd_alloc_queue(struct dasd_device * device)
+static int dasd_alloc_queue(struct dasd_block *block)
{
int rc;
- device->request_queue = blk_init_queue(do_dasd_request,
- &device->request_queue_lock);
- if (device->request_queue == NULL)
+ block->request_queue = blk_init_queue(do_dasd_request,
+ &block->request_queue_lock);
+ if (block->request_queue == NULL)
return -ENOMEM;
- device->request_queue->queuedata = device;
+ block->request_queue->queuedata = block;
- elevator_exit(device->request_queue->elevator);
- rc = elevator_init(device->request_queue, "deadline");
+ elevator_exit(block->request_queue->elevator);
+ rc = elevator_init(block->request_queue, "deadline");
if (rc) {
- blk_cleanup_queue(device->request_queue);
+ blk_cleanup_queue(block->request_queue);
return rc;
}
return 0;
@@ -1780,79 +1977,76 @@ dasd_alloc_queue(struct dasd_device * de
/*
* Allocate and initialize request queue.
*/
-static void
-dasd_setup_queue(struct dasd_device * device)
+static void dasd_setup_queue(struct dasd_block *block)
{
int max;
- blk_queue_hardsect_size(device->request_queue, device->bp_block);
- max = device->discipline->max_blocks << device->s2b_shift;
- blk_queue_max_sectors(device->request_queue, max);
- blk_queue_max_phys_segments(device->request_queue, -1L);
- blk_queue_max_hw_segments(device->request_queue, -1L);
- blk_queue_max_segment_size(device->request_queue, -1L);
- blk_queue_segment_boundary(device->request_queue, -1L);
- blk_queue_ordered(device->request_queue, QUEUE_ORDERED_TAG, NULL);
+ blk_queue_hardsect_size(block->request_queue, block->bp_block);
+ max = block->base->discipline->max_blocks << block->s2b_shift;
+ blk_queue_max_sectors(block->request_queue, max);
+ blk_queue_max_phys_segments(block->request_queue, -1L);
+ blk_queue_max_hw_segments(block->request_queue, -1L);
+ blk_queue_max_segment_size(block->request_queue, -1L);
+ blk_queue_segment_boundary(block->request_queue, -1L);
+ blk_queue_ordered(block->request_queue, QUEUE_ORDERED_DRAIN, NULL);
}
/*
* Deactivate and free request queue.
*/
-static void
-dasd_free_queue(struct dasd_device * device)
+static void dasd_free_queue(struct dasd_block *block)
{
- if (device->request_queue) {
- blk_cleanup_queue(device->request_queue);
- device->request_queue = NULL;
+ if (block->request_queue) {
+ blk_cleanup_queue(block->request_queue);
+ block->request_queue = NULL;
}
}
/*
* Flush request on the request queue.
*/
-static void
-dasd_flush_request_queue(struct dasd_device * device)
+static void dasd_flush_request_queue(struct dasd_block *block)
{
struct request *req;
- if (!device->request_queue)
+ if (!block->request_queue)
return;
- spin_lock_irq(&device->request_queue_lock);
- while ((req = elv_next_request(device->request_queue))) {
+ spin_lock_irq(&block->request_queue_lock);
+ while ((req = elv_next_request(block->request_queue))) {
blkdev_dequeue_request(req);
dasd_end_request(req, 0);
}
- spin_unlock_irq(&device->request_queue_lock);
+ spin_unlock_irq(&block->request_queue_lock);
}
-static int
-dasd_open(struct inode *inp, struct file *filp)
+static int dasd_open(struct inode *inp, struct file *filp)
{
struct gendisk *disk = inp->i_bdev->bd_disk;
- struct dasd_device *device = disk->private_data;
+ struct dasd_block *block = disk->private_data;
+ struct dasd_device *base = block->base;
int rc;
- atomic_inc(&device->open_count);
- if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+ atomic_inc(&block->open_count);
+ if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
rc = -ENODEV;
goto unlock;
}
- if (!try_module_get(device->discipline->owner)) {
+ if (!try_module_get(base->discipline->owner)) {
rc = -EINVAL;
goto unlock;
}
if (dasd_probeonly) {
- DEV_MESSAGE(KERN_INFO, device, "%s",
+ DEV_MESSAGE(KERN_INFO, base, "%s",
"No access to device due to probeonly mode");
rc = -EPERM;
goto out;
}
- if (device->state <= DASD_STATE_BASIC) {
- DBF_DEV_EVENT(DBF_ERR, device, " %s",
+ if (base->state <= DASD_STATE_BASIC) {
+ DBF_DEV_EVENT(DBF_ERR, base, " %s",
" Cannot open unrecognized device");
rc = -ENODEV;
goto out;
@@ -1861,41 +2055,41 @@ dasd_open(struct inode *inp, struct file
return 0;
out:
- module_put(device->discipline->owner);
+ module_put(base->discipline->owner);
unlock:
- atomic_dec(&device->open_count);
+ atomic_dec(&block->open_count);
return rc;
}
-static int
-dasd_release(struct inode *inp, struct file *filp)
+static int dasd_release(struct inode *inp, struct file *filp)
{
struct gendisk *disk = inp->i_bdev->bd_disk;
- struct dasd_device *device = disk->private_data;
+ struct dasd_block *block = disk->private_data;
- atomic_dec(&device->open_count);
- module_put(device->discipline->owner);
+ atomic_dec(&block->open_count);
+ module_put(block->base->discipline->owner);
return 0;
}
/*
* Return disk geometry.
*/
-static int
-dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
- struct dasd_device *device;
+ struct dasd_block *block;
+ struct dasd_device *base;
- device = bdev->bd_disk->private_data;
- if (!device)
+ block = bdev->bd_disk->private_data;
+ base = block->base;
+ if (!block)
return -ENODEV;
- if (!device->discipline ||
- !device->discipline->fill_geometry)
+ if (!base->discipline ||
+ !base->discipline->fill_geometry)
return -EINVAL;
- device->discipline->fill_geometry(device, geo);
- geo->start = get_start_sect(bdev) >> device->s2b_shift;
+ base->discipline->fill_geometry(block, geo);
+ geo->start = get_start_sect(bdev) >> block->s2b_shift;
return 0;
}
@@ -1909,6 +2103,9 @@ dasd_device_operations = {
.getgeo = dasd_getgeo,
};
+/*******************************************************************************
+ * end of block device operations
+ */
static void
dasd_exit(void)
@@ -1937,9 +2134,8 @@ dasd_exit(void)
* Initial attempt at a probe function. this can be simplified once
* the other detection code is gone.
*/
-int
-dasd_generic_probe (struct ccw_device *cdev,
- struct dasd_discipline *discipline)
+int dasd_generic_probe(struct ccw_device *cdev,
+ struct dasd_discipline *discipline)
{
int ret;
@@ -1979,10 +2175,10 @@ dasd_generic_probe (struct ccw_device *c
* This will one day be called from a global not_oper handler.
* It is also used by driver_unregister during module unload.
*/
-void
-dasd_generic_remove (struct ccw_device *cdev)
+void dasd_generic_remove(struct ccw_device *cdev)
{
struct dasd_device *device;
+ struct dasd_block *block;
cdev->handler = NULL;
@@ -2002,7 +2198,15 @@ dasd_generic_remove (struct ccw_device *
*/
dasd_set_target_state(device, DASD_STATE_NEW);
/* dasd_delete_device destroys the device reference. */
+ block = device->block;
+ device->block = NULL;
dasd_delete_device(device);
+ /*
+ * life cycle of block is bound to device, so delete it after
+ * device was safely removed
+ */
+ if (block)
+ dasd_free_block(block);
}
/*
@@ -2010,10 +2214,8 @@ dasd_generic_remove (struct ccw_device *
* the device is detected for the first time and is supposed to be used
* or the user has started activation through sysfs.
*/
-int
-dasd_generic_set_online (struct ccw_device *cdev,
- struct dasd_discipline *base_discipline)
-
+int dasd_generic_set_online(struct ccw_device *cdev,
+ struct dasd_discipline *base_discipline)
{
struct dasd_discipline *discipline;
struct dasd_device *device;
@@ -2049,6 +2251,7 @@ dasd_generic_set_online (struct ccw_devi
device->base_discipline = base_discipline;
device->discipline = discipline;
+ /* check_device will allocate block device if necessary */
rc = discipline->check_device(device);
if (rc) {
printk (KERN_WARNING
@@ -2068,6 +2271,8 @@ dasd_generic_set_online (struct ccw_devi
cdev->dev.bus_id);
rc = -ENODEV;
dasd_set_target_state(device, DASD_STATE_NEW);
+ if (device->block)
+ dasd_free_block(device->block);
dasd_delete_device(device);
} else
pr_debug("dasd_generic device %s found\n",
@@ -2082,10 +2287,10 @@ dasd_generic_set_online (struct ccw_devi
return rc;
}
-int
-dasd_generic_set_offline (struct ccw_device *cdev)
+int dasd_generic_set_offline(struct ccw_device *cdev)
{
struct dasd_device *device;
+ struct dasd_block *block;
int max_count, open_count;
device = dasd_device_from_cdev(cdev);
@@ -2102,30 +2307,39 @@ dasd_generic_set_offline (struct ccw_dev
* the blkdev_get in dasd_scan_partitions. We are only interested
* in the other openers.
*/
- max_count = device->bdev ? 0 : -1;
- open_count = (int) atomic_read(&device->open_count);
- if (open_count > max_count) {
- if (open_count > 0)
- printk (KERN_WARNING "Can't offline dasd device with "
- "open count = %i.\n",
- open_count);
- else
- printk (KERN_WARNING "%s",
- "Can't offline dasd device due to internal "
- "use\n");
- clear_bit(DASD_FLAG_OFFLINE, &device->flags);
- dasd_put_device(device);
- return -EBUSY;
+ if (device->block) {
+ struct dasd_block *block = device->block;
+ max_count = block->bdev ? 0 : -1;
+ open_count = (int) atomic_read(&block->open_count);
+ if (open_count > max_count) {
+ if (open_count > 0)
+ printk(KERN_WARNING "Can't offline dasd "
+ "device with open count = %i.\n",
+ open_count);
+ else
+ printk(KERN_WARNING "%s",
+ "Can't offline dasd device due "
+ "to internal use\n");
+ clear_bit(DASD_FLAG_OFFLINE, &device->flags);
+ dasd_put_device(device);
+ return -EBUSY;
+ }
}
dasd_set_target_state(device, DASD_STATE_NEW);
/* dasd_delete_device destroys the device reference. */
+ block = device->block;
+ device->block = NULL;
dasd_delete_device(device);
-
+ /*
+ * life cycle of block is bound to device, so delete it after
+ * device was safely removed
+ */
+ if (block)
+ dasd_free_block(block);
return 0;
}
-int
-dasd_generic_notify(struct ccw_device *cdev, int event)
+int dasd_generic_notify(struct ccw_device *cdev, int event)
{
struct dasd_device *device;
struct dasd_ccw_req *cqr;
@@ -2146,27 +2360,22 @@ dasd_generic_notify(struct ccw_device *c
if (device->state < DASD_STATE_BASIC)
break;
/* Device is active. We want to keep it. */
- if (test_bit(DASD_FLAG_DSC_ERROR, &device->flags)) {
- list_for_each_entry(cqr, &device->ccw_queue, list)
- if (cqr->status == DASD_CQR_IN_IO)
- cqr->status = DASD_CQR_FAILED;
- device->stopped |= DASD_STOPPED_DC_EIO;
- } else {
- list_for_each_entry(cqr, &device->ccw_queue, list)
- if (cqr->status == DASD_CQR_IN_IO) {
- cqr->status = DASD_CQR_QUEUED;
- cqr->retries++;
- }
- device->stopped |= DASD_STOPPED_DC_WAIT;
- dasd_set_timer(device, 0);
- }
- dasd_schedule_bh(device);
+ list_for_each_entry(cqr, &device->ccw_queue, devlist)
+ if (cqr->status == DASD_CQR_IN_IO) {
+ cqr->status = DASD_CQR_QUEUED;
+ cqr->retries++;
+ }
+ device->stopped |= DASD_STOPPED_DC_WAIT;
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
ret = 1;
break;
case CIO_OPER:
/* FIXME: add a sanity check. */
- device->stopped &= ~(DASD_STOPPED_DC_WAIT|DASD_STOPPED_DC_EIO);
- dasd_schedule_bh(device);
+ device->stopped &= ~DASD_STOPPED_DC_WAIT;
+ dasd_schedule_device_bh(device);
+ if (device->block)
+ dasd_schedule_block_bh(device->block);
ret = 1;
break;
}
@@ -2196,7 +2405,8 @@ static struct dasd_ccw_req *dasd_generic
ccw->cda = (__u32)(addr_t)rdc_buffer;
ccw->count = rdc_buffer_size;
- cqr->device = device;
+ cqr->startdev = device;
+ cqr->memdev = device;
cqr->expires = 10*HZ;
clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
cqr->retries = 2;
@@ -2218,13 +2428,12 @@ int dasd_generic_read_dev_chars(struct d
return PTR_ERR(cqr);
ret = dasd_sleep_on(cqr);
- dasd_sfree_request(cqr, cqr->device);
+ dasd_sfree_request(cqr, cqr->memdev);
return ret;
}
EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
-static int __init
-dasd_init(void)
+static int __init dasd_init(void)
{
int rc;
@@ -2232,7 +2441,7 @@ dasd_init(void)
init_waitqueue_head(&dasd_flush_wq);
/* register 'common' DASD debug area, used for all DBF_XXX calls */
- dasd_debug_area = debug_register("dasd", 1, 2, 8 * sizeof (long));
+ dasd_debug_area = debug_register("dasd", 1, 2, 8 * sizeof(long));
if (dasd_debug_area == NULL) {
rc = -ENOMEM;
goto failed;
@@ -2278,15 +2487,18 @@ EXPORT_SYMBOL(dasd_diag_discipline_point
EXPORT_SYMBOL(dasd_add_request_head);
EXPORT_SYMBOL(dasd_add_request_tail);
EXPORT_SYMBOL(dasd_cancel_req);
-EXPORT_SYMBOL(dasd_clear_timer);
+EXPORT_SYMBOL(dasd_device_clear_timer);
+EXPORT_SYMBOL(dasd_block_clear_timer);
EXPORT_SYMBOL(dasd_enable_device);
EXPORT_SYMBOL(dasd_int_handler);
EXPORT_SYMBOL(dasd_kfree_request);
EXPORT_SYMBOL(dasd_kick_device);
EXPORT_SYMBOL(dasd_kmalloc_request);
-EXPORT_SYMBOL(dasd_schedule_bh);
+EXPORT_SYMBOL(dasd_schedule_device_bh);
+EXPORT_SYMBOL(dasd_schedule_block_bh);
EXPORT_SYMBOL(dasd_set_target_state);
-EXPORT_SYMBOL(dasd_set_timer);
+EXPORT_SYMBOL(dasd_device_set_timer);
+EXPORT_SYMBOL(dasd_block_set_timer);
EXPORT_SYMBOL(dasd_sfree_request);
EXPORT_SYMBOL(dasd_sleep_on);
EXPORT_SYMBOL(dasd_sleep_on_immediatly);
@@ -2300,4 +2512,7 @@ EXPORT_SYMBOL_GPL(dasd_generic_remove);
EXPORT_SYMBOL_GPL(dasd_generic_notify);
EXPORT_SYMBOL_GPL(dasd_generic_set_online);
EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
-
+EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
+EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
+EXPORT_SYMBOL_GPL(dasd_alloc_block);
+EXPORT_SYMBOL_GPL(dasd_free_block);
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.
next prev parent reply other threads:[~2007-12-20 15:20 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-12-20 15:19 [patch 00/47] s390 2.6.25 patch queue Martin Schwidefsky
2007-12-20 15:19 ` [patch 01/47] Cleanup in Documentation/kernel-parameters.txt Martin Schwidefsky
2007-12-20 15:19 ` [patch 02/47] cio: Dump ccw device information in case of timeout Martin Schwidefsky
2007-12-20 15:19 ` [patch 03/47] cio: Use helpers instead of container_of() Martin Schwidefsky
2007-12-20 15:19 ` [patch 04/47] cio: css_driver: Use consistent parameters Martin Schwidefsky
2007-12-20 15:19 ` [patch 05/47] cio: Reset sch->driver Martin Schwidefsky
2007-12-20 15:19 ` [patch 06/47] cio: Add css_driver_{register,unregister} Martin Schwidefsky
2007-12-20 15:19 ` [patch 07/47] cio: Cleanup debug feature usage Martin Schwidefsky
2007-12-20 15:19 ` [patch 08/47] cio: Introduce subchannel->private Martin Schwidefsky
2007-12-20 15:19 ` [patch 09/47] cio: Extend adapter interrupt interface Martin Schwidefsky
2007-12-20 15:19 ` [patch 10/47] cio: I/O subchannel specific fields Martin Schwidefsky
2007-12-20 15:19 ` [patch 11/47] cio: Use dev_{g,s}et_drvdata() Martin Schwidefsky
2007-12-20 15:19 ` [patch 12/47] cio: Set driver->owner on css, ccw and ccwgroup busses Martin Schwidefsky
2007-12-20 15:19 ` [patch 13/47] cio: reduce cpu utilization during device scan Martin Schwidefsky
2007-12-20 15:19 ` [patch 14/47] qdio: Remove double checked value Martin Schwidefsky
2007-12-20 15:19 ` [patch 15/47] qdio: set QDIO_ACTIVATE_TIMEOUT to 5s Martin Schwidefsky
2007-12-20 15:19 ` [patch 16/47] sclp: sysfs interface for SCLP cpi Martin Schwidefsky
2007-12-20 15:19 ` [patch 17/47] Standby cpu activation/deactivation Martin Schwidefsky
2007-12-20 15:19 ` [patch 18/47] sclp: convert channel path configure code to use sync interface Martin Schwidefsky
2007-12-20 15:19 ` [patch 19/47] Optimize reference bit handling Martin Schwidefsky
2007-12-20 15:19 ` [patch 20/47] Fix tlb flushing with idte Martin Schwidefsky
2007-12-20 15:19 ` [patch 21/47] Change vmalloc defintions Martin Schwidefsky
2007-12-20 15:19 ` [patch 22/47] Print kernel version in dump_stack() and show_regs() Martin Schwidefsky
2007-12-20 15:19 ` [patch 23/47] Get rid of HOLES_IN_ZONE requirement Martin Schwidefsky
2007-12-20 15:19 ` [patch 24/47] DEBUG_PAGEALLOC support for s390 Martin Schwidefsky
2007-12-20 15:19 ` [patch 25/47] Remove owner_pc member from raw_spinlock_t Martin Schwidefsky
2007-12-20 15:19 ` [patch 26/47] Use new style spinlock initializer in __RWSEM_INITIALIZER Martin Schwidefsky
2007-12-20 15:19 ` [patch 27/47] Get rid of additional_cpus kernel parameter Martin Schwidefsky
2007-12-20 15:19 ` [patch 28/47] Remove appldata include from sysctl_check.c Martin Schwidefsky
2007-12-20 15:19 ` [patch 29/47] crypto: move s390 Kconfig options Martin Schwidefsky
2007-12-20 15:19 ` [patch 30/47] dasd: fix return value of dasd_generic_probe() Martin Schwidefsky
2007-12-20 15:19 ` [patch 31/47] arch/s390: Add missing "space" Martin Schwidefsky
2007-12-20 15:19 ` [patch 32/47] drivers/s390: " Martin Schwidefsky
2007-12-20 15:19 ` [patch 33/47] kernel: Shutdown Actions Interface Martin Schwidefsky
2007-12-20 15:19 ` [patch 34/47] Load disabled wait psw instead of stopping cpu on halt Martin Schwidefsky
2007-12-20 15:20 ` [patch 35/47] use LIST_HEAD instead of LIST_HEAD_INIT Martin Schwidefsky
2007-12-20 15:20 ` [patch 36/47] Allocate and free cpu lowcores and stacks when needed/possible Martin Schwidefsky
2007-12-20 15:20 ` [patch 37/47] Initialize sclp_ipl_info Martin Schwidefsky
2007-12-20 15:20 ` [patch 38/47] vmemmap: allocate struct pages before 1:1 mapping Martin Schwidefsky
2007-12-20 15:20 ` [patch 39/47] Use diag308 subcodes 3 and 6 for reboot and dump when possible Martin Schwidefsky
2007-12-20 15:20 ` [patch 40/47] arch/s390/: Spelling fixes Martin Schwidefsky
2007-12-20 15:20 ` [patch 41/47] include/asm-s390/: " Martin Schwidefsky
2007-12-20 15:20 ` [patch 42/47] drivers/s390/: " Martin Schwidefsky
2007-12-20 15:20 ` [patch 43/47] Move NOTES and BUG_TABLE Martin Schwidefsky
2007-12-20 15:20 ` [patch 44/47] single-step cleanup Martin Schwidefsky
2007-12-20 15:20 ` [patch 45/47] dasd: add hyper PAV support to DASD device driver, part 1 Martin Schwidefsky
2007-12-20 15:20 ` Martin Schwidefsky [this message]
2007-12-20 15:20 ` [patch 47/47] dasd: add hyper PAV support to DASD device driver, part 3 Martin Schwidefsky
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