On Mon, 24 Jul 2017, Damien Le Moal wrote:
> Use GFP_NOIO for memory allocations in the I/O path. Other memory > allocations in the initialization path can keep using GFP_KERNEL. Good patch. BTW. that GFP_NOFS should also be changed to GFP_NOIO. GFP_NOFS prevents allocator recursion to the filesystem. GFP_NOIO prevents allocator recursion to the filesystem and I/O stack. With GFP_NOFS, it is still theoretically possible that the allocation recurses into the I/O layer (for example when swapping to a block device). Mikulas > Problem reported by Mikulas Patocka <[email protected]>. > > Signed-off-by: Damien Le Moal <[email protected]> > --- > drivers/md/dm-zoned-metadata.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c > index f694fb98b002..f45ac8b1121d 100644 > --- a/drivers/md/dm-zoned-metadata.c > +++ b/drivers/md/dm-zoned-metadata.c > @@ -625,7 +625,7 @@ static int dmz_write_sb(struct dmz_metadata *zmd, > unsigned int set) > > ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page); > if (ret == 0) > - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); > + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); > > return ret; > } > @@ -659,7 +659,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata > *zmd, > > /* Flush drive cache (this will also sync data) */ > if (ret == 0) > - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); > + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); > > return ret; > } > @@ -723,7 +723,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd) > > /* If there are no dirty metadata blocks, just flush the device cache */ > if (list_empty(&write_list)) { > - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); > + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); > goto out; > } > > @@ -928,7 +928,7 @@ static int dmz_recover_mblocks(struct dmz_metadata *zmd, > unsigned int dst_set) > (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift); > } > > - page = alloc_page(GFP_KERNEL); > + page = alloc_page(GFP_NOIO); > if (!page) > return -ENOMEM; > > @@ -1184,7 +1184,7 @@ static int dmz_update_zone(struct dmz_metadata *zmd, > struct dm_zone *zone) > > /* Get zone information from disk */ > ret = blkdev_report_zones(zmd->dev->bdev, dmz_start_sect(zmd, zone), > - &blkz, &nr_blkz, GFP_KERNEL); > + &blkz, &nr_blkz, GFP_NOIO); > if (ret) { > dmz_dev_err(zmd->dev, "Get zone %u report failed", > dmz_id(zmd, zone)); > @@ -1258,7 +1258,7 @@ static int dmz_reset_zone(struct dmz_metadata *zmd, > struct dm_zone *zone) > > ret = blkdev_reset_zones(dev->bdev, > dmz_start_sect(zmd, zone), > - dev->zone_nr_sectors, GFP_KERNEL); > + dev->zone_nr_sectors, GFP_NOIO); > if (ret) { > dmz_dev_err(dev, "Reset zone %u failed %d", > dmz_id(zmd, zone), ret); > -- > 2.13.3 > -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
