- pass gfp_flags to get_io_context(): not all callers are forced to use
GFP_ATOMIC().
- fix locking in get_io_context(): bump the refcount whilein the exclusive
region.
- don't go oops in get_io_context() if the kmalloc failed.
- in as_get_io_context(): fail the whole thing if we were unable to
allocate the AS-specific part.
- as_remove_queued_request() cleanup
drivers/block/as-iosched.c | 50 +++++++++++++++++++++------------------------
drivers/block/ll_rw_blk.c | 9 ++++----
include/linux/blkdev.h | 2 -
3 files changed, 30 insertions(+), 31 deletions(-)
diff -puN drivers/block/ll_rw_blk.c~get_io_context-fix drivers/block/ll_rw_blk.c
--- 25/drivers/block/ll_rw_blk.c~get_io_context-fix 2003-06-16 00:22:41.000000000 -0700
+++ 25-akpm/drivers/block/ll_rw_blk.c 2003-06-16 00:22:41.000000000 -0700
@@ -1350,7 +1350,7 @@ static struct request *get_request(reque
{
struct request *rq = NULL;
struct request_list *rl = &q->rq;
- struct io_context *ioc = get_io_context();
+ struct io_context *ioc = get_io_context(gfp_mask);
spin_lock_irq(q->queue_lock);
if (rl->count[rw]+1 >= q->nr_requests) {
@@ -1437,7 +1437,7 @@ static struct request *get_request_wait(
struct io_context *ioc;
io_schedule();
- ioc = get_io_context();
+ ioc = get_io_context(GFP_NOIO);
ioc_set_batching(ioc);
put_io_context(ioc);
}
@@ -2474,7 +2474,7 @@ void exit_io_context(void)
* But weird things happen, so we disable local interrupts to ensure exclusive
* access to *current.
*/
-struct io_context *get_io_context(void)
+struct io_context *get_io_context(int gfp_flags)
{
struct task_struct *tsk = current;
unsigned long flags;
@@ -2494,8 +2494,9 @@ struct io_context *get_io_context(void)
tsk->io_context = ret;
}
}
+ if (ret)
+ atomic_inc(&ret->refcount);
local_irq_restore(flags);
- atomic_inc(&ret->refcount);
return ret;
}
diff -puN drivers/block/as-iosched.c~get_io_context-fix drivers/block/as-iosched.c
--- 25/drivers/block/as-iosched.c~get_io_context-fix 2003-06-16 00:22:46.000000000 -0700
+++ 25-akpm/drivers/block/as-iosched.c 2003-06-16 00:33:36.000000000 -0700
@@ -219,13 +219,17 @@ static struct as_io_context *alloc_as_io
*/
static struct io_context *as_get_io_context(void)
{
- struct io_context *ioc = get_io_context();
- if (ioc && !ioc->aic)
+ struct io_context *ioc = get_io_context(GFP_ATOMIC);
+ if (ioc && !ioc->aic) {
ioc->aic = alloc_as_io_context();
+ if (!ioc->aic) {
+ put_io_context(ioc);
+ ioc = NULL;
+ }
+ }
return ioc;
}
-
/*
* the back merge hash support functions
*/
@@ -971,32 +975,26 @@ static void as_completed_request(request
static void as_remove_queued_request(request_queue_t *q, struct request *rq)
{
struct as_rq *arq = RQ_DATA(rq);
+ const int data_dir = arq->is_sync;
+ struct as_data *ad = q->elevator.elevator_data;
- if (!arq)
- BUG();
- else {
- const int data_dir = arq->is_sync;
- struct as_data *ad = q->elevator.elevator_data;
-
- WARN_ON(arq->state != AS_RQ_QUEUED);
-
- if (arq->io_context && arq->io_context->aic) {
- BUG_ON(!atomic_read(&arq->io_context->aic->nr_queued));
- atomic_dec(&arq->io_context->aic->nr_queued);
- }
+ WARN_ON(arq->state != AS_RQ_QUEUED);
- /*
- * Update the "next_arq" cache if we are about to remove its
- * entry
- */
- if (ad->next_arq[data_dir] == arq)
- ad->next_arq[data_dir] = as_find_next_arq(ad, arq);
-
- list_del_init(&arq->fifo);
- as_remove_merge_hints(q, arq);
- as_del_arq_rb(ad, arq);
+ if (arq->io_context && arq->io_context->aic) {
+ BUG_ON(!atomic_read(&arq->io_context->aic->nr_queued));
+ atomic_dec(&arq->io_context->aic->nr_queued);
}
+ /*
+ * Update the "next_arq" cache if we are about to remove its
+ * entry
+ */
+ if (ad->next_arq[data_dir] == arq)
+ ad->next_arq[data_dir] = as_find_next_arq(ad, arq);
+
+ list_del_init(&arq->fifo);
+ as_remove_merge_hints(q, arq);
+ as_del_arq_rb(ad, arq);
}
/*
@@ -1292,7 +1290,7 @@ static void as_add_request(struct as_dat
arq->io_context = as_get_io_context();
- if (arq->io_context && arq->io_context->aic) {
+ if (arq->io_context) {
atomic_inc(&arq->io_context->aic->nr_queued);
as_update_iohist(arq->io_context->aic, arq->request);
}
diff -puN include/linux/blkdev.h~get_io_context-fix include/linux/blkdev.h
--- 25/include/linux/blkdev.h~get_io_context-fix 2003-06-16 00:24:51.000000000 -0700
+++ 25-akpm/include/linux/blkdev.h 2003-06-16 00:25:03.000000000 -0700
@@ -70,7 +70,7 @@ struct io_context {
void put_io_context(struct io_context *ioc);
void exit_io_context(void);
-struct io_context *get_io_context(void);
+struct io_context *get_io_context(int gfp_flags);
void copy_io_context(struct io_context **pdst, struct io_context **psrc);
void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
_