From: Sergey Senozhatsky Date: Mon, 7 Apr 2014 22:38:19 +0000 (-0700) Subject: zram: move comp allocation out of init_lock X-Git-Tag: Ubuntu-snapdragon-4.4.0-1029.32~8938^2~83 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=d61f98c70e8b0d324e8e83be2ed546d6295e63f3;p=mirror_ubuntu-zesty-kernel.git zram: move comp allocation out of init_lock While fixing lockdep spew of ->init_lock reported by Sasha Levin [1], Minchan Kim noted [2] that it's better to move compression backend allocation (using GPF_KERNEL) out of the ->init_lock lock, same way as with zram_meta_alloc(), in order to prevent the same lockdep spew. [1] https://lkml.org/lkml/2014/2/27/337 [2] https://lkml.org/lkml/2014/3/3/32 Signed-off-by: Sergey Senozhatsky Reported-by: Minchan Kim Acked-by: Minchan Kim Cc: Sasha Levin Acked-by: Jerome Marchand Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 15d46f2e158c..e4d536b485e6 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -580,9 +580,10 @@ static ssize_t disksize_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { u64 disksize; + struct zcomp *comp; struct zram_meta *meta; struct zram *zram = dev_to_zram(dev); - int err; + int err = -EINVAL; disksize = memparse(buf, NULL); if (!disksize) @@ -593,30 +594,32 @@ static ssize_t disksize_store(struct device *dev, if (!meta) return -ENOMEM; + comp = zcomp_create(zram->compressor, zram->max_comp_streams); + if (!comp) { + pr_info("Cannot initialise %s compressing backend\n", + zram->compressor); + goto out_cleanup; + } + down_write(&zram->init_lock); if (init_done(zram)) { + up_write(&zram->init_lock); pr_info("Cannot change disksize for initialized device\n"); err = -EBUSY; - goto out_free_meta; - } - - zram->comp = zcomp_create(zram->compressor, zram->max_comp_streams); - if (!zram->comp) { - pr_info("Cannot initialise %s compressing backend\n", - zram->compressor); - err = -EINVAL; - goto out_free_meta; + goto out_cleanup; } zram->meta = meta; + zram->comp = comp; zram->disksize = disksize; set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); up_write(&zram->init_lock); return len; -out_free_meta: - up_write(&zram->init_lock); +out_cleanup: + if (comp) + zcomp_destroy(comp); zram_meta_free(meta); return err; }