From 0a70bd43053331d99881211e1d09f32de531432f Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 24 Feb 2016 14:02:11 -0800 Subject: [PATCH] dax: enable dax in the presence of known media errors (badblocks) 1/ If a mapping overlaps a bad sector fail the request. 2/ Do not opportunistically report more dax-capable capacity than is requested when errors present. Reviewed-by: Jeff Moyer Reviewed-by: Christoph Hellwig Signed-off-by: Dan Williams [vishal: fix a conflict with system RAM collision patches] [vishal: add a 'size' parameter to ->direct_access] [vishal: fix a conflict with DAX alignment check patches] Signed-off-by: Vishal Verma --- arch/powerpc/sysdev/axonram.c | 2 +- drivers/block/brd.c | 2 +- drivers/nvdimm/pmem.c | 10 +++++++++- drivers/s390/block/dcssblk.c | 4 ++-- fs/block_dev.c | 13 +------------ include/linux/blkdev.h | 2 +- 6 files changed, 15 insertions(+), 18 deletions(-) diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c index 0d112b94d91d..ff75d70f7285 100644 --- a/arch/powerpc/sysdev/axonram.c +++ b/arch/powerpc/sysdev/axonram.c @@ -143,7 +143,7 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio) */ static long axon_ram_direct_access(struct block_device *device, sector_t sector, - void __pmem **kaddr, pfn_t *pfn) + void __pmem **kaddr, pfn_t *pfn, long size) { struct axon_ram_bank *bank = device->bd_disk->private_data; loff_t offset = (loff_t)sector << AXON_RAM_SECTOR_SHIFT; diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 51a071e32221..c04bd9bc39fd 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -381,7 +381,7 @@ static int brd_rw_page(struct block_device *bdev, sector_t sector, #ifdef CONFIG_BLK_DEV_RAM_DAX static long brd_direct_access(struct block_device *bdev, sector_t sector, - void __pmem **kaddr, pfn_t *pfn) + void __pmem **kaddr, pfn_t *pfn, long size) { struct brd_device *brd = bdev->bd_disk->private_data; struct page *page; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index f798899338ed..c447579bd853 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -182,14 +182,22 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector, } static long pmem_direct_access(struct block_device *bdev, sector_t sector, - void __pmem **kaddr, pfn_t *pfn) + void __pmem **kaddr, pfn_t *pfn, long size) { struct pmem_device *pmem = bdev->bd_disk->private_data; resource_size_t offset = sector * 512 + pmem->data_offset; + if (unlikely(is_bad_pmem(&pmem->bb, sector, size))) + return -EIO; *kaddr = pmem->virt_addr + offset; *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); + /* + * If badblocks are present, limit known good range to the + * requested range. + */ + if (unlikely(pmem->bb.count)) + return size; return pmem->size - pmem->pfn_pad - offset; } diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index 1bce9cf51b1e..6ac33984bc0f 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -31,7 +31,7 @@ static void dcssblk_release(struct gendisk *disk, fmode_t mode); static blk_qc_t dcssblk_make_request(struct request_queue *q, struct bio *bio); static long dcssblk_direct_access(struct block_device *bdev, sector_t secnum, - void __pmem **kaddr, pfn_t *pfn); + void __pmem **kaddr, pfn_t *pfn, long size); static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; @@ -883,7 +883,7 @@ dcssblk_make_request(struct request_queue *q, struct bio *bio) static long dcssblk_direct_access (struct block_device *bdev, sector_t secnum, - void __pmem **kaddr, pfn_t *pfn) + void __pmem **kaddr, pfn_t *pfn, long size) { struct dcssblk_dev_info *dev_info; unsigned long offset, dev_sz; diff --git a/fs/block_dev.c b/fs/block_dev.c index 8477d4501b1e..45839b27972c 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -29,7 +29,6 @@ #include #include #include -#include #include #include "internal.h" @@ -501,7 +500,7 @@ long bdev_direct_access(struct block_device *bdev, struct blk_dax_ctl *dax) sector += get_start_sect(bdev); if (sector % (PAGE_SIZE / 512)) return -EINVAL; - avail = ops->direct_access(bdev, sector, &dax->addr, &dax->pfn); + avail = ops->direct_access(bdev, sector, &dax->addr, &dax->pfn, size); if (!avail) return -ERANGE; if (avail > 0 && avail & ~PAGE_MASK) @@ -561,7 +560,6 @@ EXPORT_SYMBOL_GPL(bdev_dax_supported); */ bool bdev_dax_capable(struct block_device *bdev) { - struct gendisk *disk = bdev->bd_disk; struct blk_dax_ctl dax = { .size = PAGE_SIZE, }; @@ -577,15 +575,6 @@ bool bdev_dax_capable(struct block_device *bdev) if (bdev_direct_access(bdev, &dax) < 0) return false; - /* - * If the device has known bad blocks, force all I/O through the - * driver / page cache. - * - * TODO: support finer grained dax error handling - */ - if (disk->bb && disk->bb->count) - return false; - return true; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 27cbefe8c985..cf7c13c2c38d 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1668,7 +1668,7 @@ struct block_device_operations { int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); long (*direct_access)(struct block_device *, sector_t, void __pmem **, - pfn_t *); + pfn_t *, long); unsigned int (*check_events) (struct gendisk *disk, unsigned int clearing); /* ->media_changed() is DEPRECATED, use ->check_events() instead */