diff options
| author | Mike Galbraith <umgwanakikbuti@gmail.com> | 2016-10-20 11:15:22 +0200 |
|---|---|---|
| committer | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-12-23 17:15:33 +0100 |
| commit | 6f84f4755f4273519ffc937610365332ca1e2abb (patch) | |
| tree | 20654341ab2b02d0b23a2201c05c28cd2ee5139c /drivers/block | |
| parent | 7d392b73ab8ebdf4fbf047db878ee97bf3d0cd8b (diff) | |
drivers/zram: Don't disable preemption in zcomp_stream_get/put()
In v4.7, the driver switched to percpu compression streams, disabling
preemption via get/put_cpu_ptr(). Use a per-zcomp_strm lock here. We
also have to fix an lock order issue in zram_decompress_page() such
that zs_map_object() nests inside of zcomp_stream_put() as it does in
zram_bvec_write().
Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
[bigeasy: get_locked_var() -> per zcomp_strm lock]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/zram/zcomp.c | 12 | ||||
| -rw-r--r-- | drivers/block/zram/zcomp.h | 1 | ||||
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 6 |
3 files changed, 14 insertions, 5 deletions
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c index 4b5cd3a7b2b6..fa8329ad79fd 100644 --- a/drivers/block/zram/zcomp.c +++ b/drivers/block/zram/zcomp.c @@ -118,12 +118,19 @@ ssize_t zcomp_available_show(const char *comp, char *buf) struct zcomp_strm *zcomp_stream_get(struct zcomp *comp) { - return *get_cpu_ptr(comp->stream); + struct zcomp_strm *zstrm; + + zstrm = *this_cpu_ptr(comp->stream); + spin_lock(&zstrm->zcomp_lock); + return zstrm; } void zcomp_stream_put(struct zcomp *comp) { - put_cpu_ptr(comp->stream); + struct zcomp_strm *zstrm; + + zstrm = *this_cpu_ptr(comp->stream); + spin_unlock(&zstrm->zcomp_lock); } int zcomp_compress(struct zcomp_strm *zstrm, @@ -174,6 +181,7 @@ static int __zcomp_cpu_notifier(struct zcomp *comp, pr_err("Can't allocate a compression stream\n"); return NOTIFY_BAD; } + spin_lock_init(&zstrm->zcomp_lock); *per_cpu_ptr(comp->stream, cpu) = zstrm; break; case CPU_DEAD: diff --git a/drivers/block/zram/zcomp.h b/drivers/block/zram/zcomp.h index 478cac2ed465..f7a6efdc3285 100644 --- a/drivers/block/zram/zcomp.h +++ b/drivers/block/zram/zcomp.h @@ -14,6 +14,7 @@ struct zcomp_strm { /* compression/decompression buffer */ void *buffer; struct crypto_comp *tfm; + spinlock_t zcomp_lock; }; /* dynamic per-device compression frontend */ diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index b793fe065a9d..3826072a23c5 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -568,6 +568,7 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index) struct zram_meta *meta = zram->meta; unsigned long handle; unsigned int size; + struct zcomp_strm *zstrm; zram_lock_table(&meta->table[index]); handle = meta->table[index].handle; @@ -579,16 +580,15 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index) return 0; } + zstrm = zcomp_stream_get(zram->comp); cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); if (size == PAGE_SIZE) { copy_page(mem, cmem); } else { - struct zcomp_strm *zstrm = zcomp_stream_get(zram->comp); - ret = zcomp_decompress(zstrm, cmem, size, mem); - zcomp_stream_put(zram->comp); } zs_unmap_object(meta->mem_pool, handle); + zcomp_stream_put(zram->comp); zram_unlock_table(&meta->table[index]); /* Should NEVER happen. Return bio error if it does. */ |