From af498d7fa3e786f52650819a56e117ed9a40920c Mon Sep 17 00:00:00 2001 From: Kazuhisa Ichikawa Date: Tue, 12 May 2009 13:27:45 +0200 Subject: block: fix the bio_vec array index out-of-bounds test Current bio_vec array index out-of-bounds test within __end_that_request_first() does not seem correct. It checks bio->bi_idx against bio->bi_vcnt, but the subsequent code uses idx (which is, bio->bi_idx + next_idx) as the array index into bio_vec array. This means that the test really make sense only at the first iteration of !(nr_bytes >=bio->bi_size) case (when next_idx == zero). Fix this by replacing bio->bi_idx with idx. (This patch applies to 2.6.30-rc4.) Signed-off-by: Kazuhisa Ichikawa Signed-off-by: Jens Axboe --- block/blk-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 2998fe3..c89883b 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1768,10 +1768,10 @@ static int __end_that_request_first(struct request *req, int error, } else { int idx = bio->bi_idx + next_idx; - if (unlikely(bio->bi_idx >= bio->bi_vcnt)) { + if (unlikely(idx >= bio->bi_vcnt)) { blk_dump_rq_flags(req, "__end_that"); printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n", - __func__, bio->bi_idx, bio->bi_vcnt); + __func__, idx, bio->bi_vcnt); break; } -- cgit v1.1 From 05dc7b613481c695bb4fc476c6fbb46364b63f62 Mon Sep 17 00:00:00 2001 From: Alexander Beregalov Date: Tue, 12 May 2009 13:28:23 +0200 Subject: viocd: needs to depend on BLOCK Fix this build error when CONFIG_BLOCK is not set: drivers/cdrom/viocd.c: In function 'viocd_blk_open': drivers/cdrom/viocd.c:156: error: dereferencing pointer to incomplete type drivers/cdrom/viocd.c: In function 'viocd_blk_release': drivers/cdrom/viocd.c:162: error: dereferencing pointer to incomplete type drivers/cdrom/viocd.c: In function 'viocd_blk_ioctl': drivers/cdrom/viocd.c:170: error: dereferencing pointer to incomplete type drivers/cdrom/viocd.c: In function 'viocd_blk_media_changed': drivers/cdrom/viocd.c:176: error: dereferencing pointer to incomplete type ... Signed-off-by: Alexander Beregalov Signed-off-by: Jens Axboe --- arch/powerpc/platforms/iseries/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/platforms/iseries/Kconfig b/arch/powerpc/platforms/iseries/Kconfig index 647e877..47a20cf 100644 --- a/arch/powerpc/platforms/iseries/Kconfig +++ b/arch/powerpc/platforms/iseries/Kconfig @@ -17,6 +17,7 @@ config VIODASD config VIOCD tristate "iSeries Virtual I/O CD support" + depends on BLOCK select VIOPATH help If you are running Linux on an IBM iSeries system and you want to -- cgit v1.1 From cd17cbfda004fe5f406c01b318c6378d9895896f Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 15 May 2009 11:32:24 +0200 Subject: Revert "mm: add /proc controls for pdflush threads" This reverts commit fafd688e4c0c34da0f3de909881117d374e4c7af. Work is progressing to switch away from pdflush as the process backing for flushing out dirty data. So it seems pointless to add more knobs to control pdflush threads. The original author of the patch did not have any specific use cases for adding the knobs, so we can easily revert this before 2.6.30 to avoid having to maintain this API forever. Signed-off-by: Jens Axboe --- Documentation/sysctl/vm.txt | 28 ---------------------------- include/linux/writeback.h | 2 -- kernel/sysctl.c | 23 ----------------------- mm/pdflush.c | 31 ++++++++++++------------------- 4 files changed, 12 insertions(+), 72 deletions(-) diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index b716d33..c302ddf 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -39,8 +39,6 @@ Currently, these files are in /proc/sys/vm: - nr_hugepages - nr_overcommit_hugepages - nr_pdflush_threads -- nr_pdflush_threads_min -- nr_pdflush_threads_max - nr_trim_pages (only if CONFIG_MMU=n) - numa_zonelist_order - oom_dump_tasks @@ -469,32 +467,6 @@ The default value is 0. ============================================================== -nr_pdflush_threads_min - -This value controls the minimum number of pdflush threads. - -At boot time, the kernel will create and maintain 'nr_pdflush_threads_min' -threads for the kernel's lifetime. - -The default value is 2. The minimum value you can specify is 1, and -the maximum value is the current setting of 'nr_pdflush_threads_max'. - -See 'nr_pdflush_threads_max' below for more information. - -============================================================== - -nr_pdflush_threads_max - -This value controls the maximum number of pdflush threads that can be -created. The pdflush algorithm will create a new pdflush thread (up to -this maximum) if no pdflush threads have been available for >= 1 second. - -The default value is 8. The minimum value you can specify is the -current value of 'nr_pdflush_threads_min' and the -maximum is 1000. - -============================================================== - overcommit_memory: This value contains a flag that enables memory overcommitment. diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 9c1ed1f..9344547 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -168,8 +168,6 @@ void writeback_set_ratelimit(void); /* pdflush.c */ extern int nr_pdflush_threads; /* Global so it can be exported to sysctl read-only. */ -extern int nr_pdflush_threads_max; /* Global so it can be exported to sysctl */ -extern int nr_pdflush_threads_min; /* Global so it can be exported to sysctl */ #endif /* WRITEBACK_H */ diff --git a/kernel/sysctl.c b/kernel/sysctl.c index ea78fa1..b2970d5 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -101,7 +101,6 @@ static int __maybe_unused one = 1; static int __maybe_unused two = 2; static unsigned long one_ul = 1; static int one_hundred = 100; -static int one_thousand = 1000; /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ static unsigned long dirty_bytes_min = 2 * PAGE_SIZE; @@ -1034,28 +1033,6 @@ static struct ctl_table vm_table[] = { .proc_handler = &proc_dointvec, }, { - .ctl_name = CTL_UNNUMBERED, - .procname = "nr_pdflush_threads_min", - .data = &nr_pdflush_threads_min, - .maxlen = sizeof nr_pdflush_threads_min, - .mode = 0644 /* read-write */, - .proc_handler = &proc_dointvec_minmax, - .strategy = &sysctl_intvec, - .extra1 = &one, - .extra2 = &nr_pdflush_threads_max, - }, - { - .ctl_name = CTL_UNNUMBERED, - .procname = "nr_pdflush_threads_max", - .data = &nr_pdflush_threads_max, - .maxlen = sizeof nr_pdflush_threads_max, - .mode = 0644 /* read-write */, - .proc_handler = &proc_dointvec_minmax, - .strategy = &sysctl_intvec, - .extra1 = &nr_pdflush_threads_min, - .extra2 = &one_thousand, - }, - { .ctl_name = VM_SWAPPINESS, .procname = "swappiness", .data = &vm_swappiness, diff --git a/mm/pdflush.c b/mm/pdflush.c index f2caf96..235ac44 100644 --- a/mm/pdflush.c +++ b/mm/pdflush.c @@ -58,14 +58,6 @@ static DEFINE_SPINLOCK(pdflush_lock); int nr_pdflush_threads = 0; /* - * The max/min number of pdflush threads. R/W by sysctl at - * /proc/sys/vm/nr_pdflush_threads_max/min - */ -int nr_pdflush_threads_max __read_mostly = MAX_PDFLUSH_THREADS; -int nr_pdflush_threads_min __read_mostly = MIN_PDFLUSH_THREADS; - - -/* * The time at which the pdflush thread pool last went empty */ static unsigned long last_empty_jifs; @@ -76,7 +68,7 @@ static unsigned long last_empty_jifs; * Thread pool management algorithm: * * - The minimum and maximum number of pdflush instances are bound - * by nr_pdflush_threads_min and nr_pdflush_threads_max. + * by MIN_PDFLUSH_THREADS and MAX_PDFLUSH_THREADS. * * - If there have been no idle pdflush instances for 1 second, create * a new one. @@ -142,13 +134,14 @@ static int __pdflush(struct pdflush_work *my_work) * To throttle creation, we reset last_empty_jifs. */ if (time_after(jiffies, last_empty_jifs + 1 * HZ)) { - if (list_empty(&pdflush_list) && - nr_pdflush_threads < nr_pdflush_threads_max) { - last_empty_jifs = jiffies; - nr_pdflush_threads++; - spin_unlock_irq(&pdflush_lock); - start_one_pdflush_thread(); - spin_lock_irq(&pdflush_lock); + if (list_empty(&pdflush_list)) { + if (nr_pdflush_threads < MAX_PDFLUSH_THREADS) { + last_empty_jifs = jiffies; + nr_pdflush_threads++; + spin_unlock_irq(&pdflush_lock); + start_one_pdflush_thread(); + spin_lock_irq(&pdflush_lock); + } } } @@ -160,7 +153,7 @@ static int __pdflush(struct pdflush_work *my_work) */ if (list_empty(&pdflush_list)) continue; - if (nr_pdflush_threads <= nr_pdflush_threads_min) + if (nr_pdflush_threads <= MIN_PDFLUSH_THREADS) continue; pdf = list_entry(pdflush_list.prev, struct pdflush_work, list); if (time_after(jiffies, pdf->when_i_went_to_sleep + 1 * HZ)) { @@ -266,9 +259,9 @@ static int __init pdflush_init(void) * Pre-set nr_pdflush_threads... If we fail to create, * the count will be decremented. */ - nr_pdflush_threads = nr_pdflush_threads_min; + nr_pdflush_threads = MIN_PDFLUSH_THREADS; - for (i = 0; i < nr_pdflush_threads_min; i++) + for (i = 0; i < MIN_PDFLUSH_THREADS; i++) start_one_pdflush_thread(); return 0; } -- cgit v1.1