/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (C) 2011 Lawrence Livermore National Security, LLC. * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). * Written by Brian Behlendorf . * LLNL-CODE-403049. */ #ifndef _ZFS_BLKDEV_H #define _ZFS_BLKDEV_H #include #include #include #ifndef HAVE_FMODE_T typedef unsigned __bitwise__ fmode_t; #endif /* HAVE_FMODE_T */ /* * 4.7 - 4.x API, * The blk_queue_write_cache() interface has replaced blk_queue_flush() * interface. However, the new interface is GPL-only thus we implement * our own trivial wrapper when the GPL-only version is detected. * * 2.6.36 - 4.6 API, * The blk_queue_flush() interface has replaced blk_queue_ordered() * interface. However, while the old interface was available to all the * new one is GPL-only. Thus if the GPL-only version is detected we * implement our own trivial helper. * * 2.6.x - 2.6.35 * Legacy blk_queue_ordered() interface. */ static inline void blk_queue_set_write_cache(struct request_queue *q, bool wc, bool fua) { #if defined(HAVE_BLK_QUEUE_WRITE_CACHE_GPL_ONLY) spin_lock_irq(q->queue_lock); if (wc) queue_flag_set(QUEUE_FLAG_WC, q); else queue_flag_clear(QUEUE_FLAG_WC, q); if (fua) queue_flag_set(QUEUE_FLAG_FUA, q); else queue_flag_clear(QUEUE_FLAG_FUA, q); spin_unlock_irq(q->queue_lock); #elif defined(HAVE_BLK_QUEUE_WRITE_CACHE) blk_queue_write_cache(q, wc, fua); #elif defined(HAVE_BLK_QUEUE_FLUSH_GPL_ONLY) if (wc) q->flush_flags |= REQ_FLUSH; if (fua) q->flush_flags |= REQ_FUA; #elif defined(HAVE_BLK_QUEUE_FLUSH) blk_queue_flush(q, (wc ? REQ_FLUSH : 0) | (fua ? REQ_FUA : 0)); #else blk_queue_ordered(q, QUEUE_ORDERED_DRAIN, NULL); #endif } /* * Most of the blk_* macros were removed in 2.6.36. Ostensibly this was * done to improve readability and allow easier grepping. However, from * a portability stand point the macros are helpful. Therefore the needed * macros are redefined here if they are missing from the kernel. */ #ifndef blk_fs_request #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) #endif /* * 2.6.27 API change, * The blk_queue_stackable() queue flag was added in 2.6.27 to handle dm * stacking drivers. Prior to this request stacking drivers were detected * by checking (q->request_fn == NULL), for earlier kernels we revert to * this legacy behavior. */ #ifndef blk_queue_stackable #define blk_queue_stackable(q) ((q)->request_fn == NULL) #endif /* * 2.6.34 API change, * The blk_queue_max_hw_sectors() function replaces blk_queue_max_sectors(). */ #ifndef HAVE_BLK_QUEUE_MAX_HW_SECTORS #define blk_queue_max_hw_sectors __blk_queue_max_hw_sectors static inline void __blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors) { blk_queue_max_sectors(q, max_hw_sectors); } #endif /* * 2.6.34 API change, * The blk_queue_max_segments() function consolidates * blk_queue_max_hw_segments() and blk_queue_max_phys_segments(). */ #ifndef HAVE_BLK_QUEUE_MAX_SEGMENTS #define blk_queue_max_segments __blk_queue_max_segments static inline void __blk_queue_max_segments(struct request_queue *q, unsigned short max_segments) { blk_queue_max_phys_segments(q, max_segments); blk_queue_max_hw_segments(q, max_segments); } #endif static inline void blk_queue_set_read_ahead(struct request_queue *q, unsigned long ra_pages) { #ifdef HAVE_BLK_QUEUE_BDI_DYNAMIC q->backing_dev_info->ra_pages = ra_pages; #else q->backing_dev_info.ra_pages = ra_pages; #endif } #ifndef HAVE_GET_DISK_AND_MODULE static inline struct kobject * get_disk_and_module(struct gendisk *disk) { return (get_disk(disk)); } #endif #ifndef HAVE_GET_DISK_RO static inline int get_disk_ro(struct gendisk *disk) { int policy = 0; if (disk->part[0]) policy = disk->part[0]->policy; return (policy); } #endif /* HAVE_GET_DISK_RO */ #ifdef HAVE_BIO_BVEC_ITER #define BIO_BI_SECTOR(bio) (bio)->bi_iter.bi_sector #define BIO_BI_SIZE(bio) (bio)->bi_iter.bi_size #define BIO_BI_IDX(bio) (bio)->bi_iter.bi_idx #define BIO_BI_SKIP(bio) (bio)->bi_iter.bi_bvec_done #define bio_for_each_segment4(bv, bvp, b, i) \ bio_for_each_segment((bv), (b), (i)) typedef struct bvec_iter bvec_iterator_t; #else #define BIO_BI_SECTOR(bio) (bio)->bi_sector #define BIO_BI_SIZE(bio) (bio)->bi_size #define BIO_BI_IDX(bio) (bio)->bi_idx #define BIO_BI_SKIP(bio) (0) #define bio_for_each_segment4(bv, bvp, b, i) \ bio_for_each_segment((bvp), (b), (i)) typedef int bvec_iterator_t; #endif /* * Portable helper for correctly setting the FAILFAST flags. The * correct usage has changed 3 times from 2.6.12 to 2.6.38. */ static inline void bio_set_flags_failfast(struct block_device *bdev, int *flags) { #ifdef CONFIG_BUG /* * Disable FAILFAST for loopback devices because of the * following incorrect BUG_ON() in loop_make_request(). * This support is also disabled for md devices because the * test suite layers md devices on top of loopback devices. * This may be removed when the loopback driver is fixed. * * BUG_ON(!lo || (rw != READ && rw != WRITE)); */ if ((MAJOR(bdev->bd_dev) == LOOP_MAJOR) || (MAJOR(bdev->bd_dev) == MD_MAJOR)) return; #ifdef BLOCK_EXT_MAJOR if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR) return; #endif /* BLOCK_EXT_MAJOR */ #endif /* CONFIG_BUG */ #if defined(HAVE_BIO_RW_FAILFAST_DTD) /* BIO_RW_FAILFAST_* preferred interface from 2.6.28 - 2.6.35 */ *flags |= ( (1 << BIO_RW_FAILFAST_DEV) | (1 << BIO_RW_FAILFAST_TRANSPORT) | (1 << BIO_RW_FAILFAST_DRIVER)); #elif defined(HAVE_REQ_FAILFAST_MASK) /* * REQ_FAILFAST_* preferred interface from 2.6.36 - 2.6.xx, * the BIO_* and REQ_* flags were unified under REQ_* flags. */ *flags |= REQ_FAILFAST_MASK; #else #error "Undefined block IO FAILFAST interface." #endif } /* * Maximum disk label length, it may be undefined for some kernels. */ #ifndef DISK_NAME_LEN #define DISK_NAME_LEN 32 #endif /* DISK_NAME_LEN */ #ifdef HAVE_BIO_BI_STATUS static inline int bi_status_to_errno(blk_status_t status) { switch (status) { case BLK_STS_OK: return (0); case BLK_STS_NOTSUPP: return (EOPNOTSUPP); case BLK_STS_TIMEOUT: return (ETIMEDOUT); case BLK_STS_NOSPC: return (ENOSPC); case BLK_STS_TRANSPORT: return (ENOLINK); case BLK_STS_TARGET: return (EREMOTEIO); case BLK_STS_NEXUS: return (EBADE); case BLK_STS_MEDIUM: return (ENODATA); case BLK_STS_PROTECTION: return (EILSEQ); case BLK_STS_RESOURCE: return (ENOMEM); case BLK_STS_AGAIN: return (EAGAIN); case BLK_STS_IOERR: return (EIO); default: return (EIO); } } static inline blk_status_t errno_to_bi_status(int error) { switch (error) { case 0: return (BLK_STS_OK); case EOPNOTSUPP: return (BLK_STS_NOTSUPP); case ETIMEDOUT: return (BLK_STS_TIMEOUT); case ENOSPC: return (BLK_STS_NOSPC); case ENOLINK: return (BLK_STS_TRANSPORT); case EREMOTEIO: return (BLK_STS_TARGET); case EBADE: return (BLK_STS_NEXUS); case ENODATA: return (BLK_STS_MEDIUM); case EILSEQ: return (BLK_STS_PROTECTION); case ENOMEM: return (BLK_STS_RESOURCE); case EAGAIN: return (BLK_STS_AGAIN); case EIO: return (BLK_STS_IOERR); default: return (BLK_STS_IOERR); } } #endif /* HAVE_BIO_BI_STATUS */ /* * 4.3 API change * The bio_endio() prototype changed slightly. These are helper * macro's to ensure the prototype and invocation are handled. */ #ifdef HAVE_1ARG_BIO_END_IO_T #ifdef HAVE_BIO_BI_STATUS #define BIO_END_IO_ERROR(bio) bi_status_to_errno(bio->bi_status) #define BIO_END_IO_PROTO(fn, x, z) static void fn(struct bio *x) #define BIO_END_IO(bio, error) bio_set_bi_status(bio, error) static inline void bio_set_bi_status(struct bio *bio, int error) { ASSERT3S(error, <=, 0); bio->bi_status = errno_to_bi_status(-error); bio_endio(bio); } #else #define BIO_END_IO_ERROR(bio) (-(bio->bi_error)) #define BIO_END_IO_PROTO(fn, x, z) static void fn(struct bio *x) #define BIO_END_IO(bio, error) bio_set_bi_error(bio, error) static inline void bio_set_bi_error(struct bio *bio, int error) { ASSERT3S(error, <=, 0); bio->bi_error = error; bio_endio(bio); } #endif /* HAVE_BIO_BI_STATUS */ #else #define BIO_END_IO_PROTO(fn, x, z) static void fn(struct bio *x, int z) #define BIO_END_IO(bio, error) bio_endio(bio, error); #endif /* HAVE_1ARG_BIO_END_IO_T */ /* * 2.6.38 - 2.6.x API, * blkdev_get_by_path() * blkdev_put() * * 2.6.28 - 2.6.37 API, * open_bdev_exclusive() * close_bdev_exclusive() * * 2.6.12 - 2.6.27 API, * open_bdev_excl() * close_bdev_excl() * * Used to exclusively open a block device from within the kernel. */ #if defined(HAVE_BLKDEV_GET_BY_PATH) #define vdev_bdev_open(path, md, hld) blkdev_get_by_path(path, \ (md) | FMODE_EXCL, hld) #define vdev_bdev_close(bdev, md) blkdev_put(bdev, (md) | FMODE_EXCL) #elif defined(HAVE_OPEN_BDEV_EXCLUSIVE) #define vdev_bdev_open(path, md, hld) open_bdev_exclusive(path, md, hld) #define vdev_bdev_close(bdev, md) close_bdev_exclusive(bdev, md) #else #define vdev_bdev_open(path, md, hld) open_bdev_excl(path, md, hld) #define vdev_bdev_close(bdev, md) close_bdev_excl(bdev) #endif /* HAVE_BLKDEV_GET_BY_PATH | HAVE_OPEN_BDEV_EXCLUSIVE */ /* * 2.6.22 API change * The function invalidate_bdev() lost it's second argument because * it was unused. */ #ifdef HAVE_1ARG_INVALIDATE_BDEV #define vdev_bdev_invalidate(bdev) invalidate_bdev(bdev) #else #define vdev_bdev_invalidate(bdev) invalidate_bdev(bdev, 1) #endif /* HAVE_1ARG_INVALIDATE_BDEV */ /* * 2.6.27 API change * The function was exported for use, prior to this it existed but the * symbol was not exported. * * 4.4.0-6.21 API change for Ubuntu * lookup_bdev() gained a second argument, FMODE_*, to check inode permissions. */ #ifdef HAVE_1ARG_LOOKUP_BDEV #define vdev_lookup_bdev(path) lookup_bdev(path) #else #ifdef HAVE_2ARGS_LOOKUP_BDEV #define vdev_lookup_bdev(path) lookup_bdev(path, 0) #else #define vdev_lookup_bdev(path) ERR_PTR(-ENOTSUP) #endif /* HAVE_2ARGS_LOOKUP_BDEV */ #endif /* HAVE_1ARG_LOOKUP_BDEV */ /* * 2.6.30 API change * To ensure good performance preferentially use the physical block size * for proper alignment. The physical size is supposed to be the internal * sector size used by the device. This is often 4096 byte for AF devices, * while a smaller 512 byte logical size is supported for compatibility. * * Unfortunately, many drives still misreport their physical sector size. * For devices which are known to lie you may need to manually set this * at pool creation time with 'zpool create -o ashift=12 ...'. * * When the physical block size interface isn't available, we fall back to * the logical block size interface and then the older hard sector size. */ #ifdef HAVE_BDEV_PHYSICAL_BLOCK_SIZE #define vdev_bdev_block_size(bdev) bdev_physical_block_size(bdev) #else #ifdef HAVE_BDEV_LOGICAL_BLOCK_SIZE #define vdev_bdev_block_size(bdev) bdev_logical_block_size(bdev) #else #define vdev_bdev_block_size(bdev) bdev_hardsect_size(bdev) #endif /* HAVE_BDEV_LOGICAL_BLOCK_SIZE */ #endif /* HAVE_BDEV_PHYSICAL_BLOCK_SIZE */ #ifndef HAVE_BIO_SET_OP_ATTRS /* * Kernels without bio_set_op_attrs use bi_rw for the bio flags. */ static inline void bio_set_op_attrs(struct bio *bio, unsigned rw, unsigned flags) { bio->bi_rw |= rw | flags; } #endif /* * bio_set_flush - Set the appropriate flags in a bio to guarantee * data are on non-volatile media on completion. * * 2.6.X - 2.6.36 API, * WRITE_BARRIER - Tells the block layer to commit all previously submitted * writes to stable storage before this one is started and that the current * write is on stable storage upon completion. Also prevents reordering * on both sides of the current operation. * * 2.6.37 - 4.8 API, * Introduce WRITE_FLUSH, WRITE_FUA, and WRITE_FLUSH_FUA flags as a * replacement for WRITE_BARRIER to allow expressing richer semantics * to the block layer. It's up to the block layer to implement the * semantics correctly. Use the WRITE_FLUSH_FUA flag combination. * * 4.8 - 4.9 API, * REQ_FLUSH was renamed to REQ_PREFLUSH. For consistency with previous * ZoL releases, prefer the WRITE_FLUSH_FUA flag set if it's available. * * 4.10 API, * The read/write flags and their modifiers, including WRITE_FLUSH, * WRITE_FUA and WRITE_FLUSH_FUA were removed from fs.h in * torvalds/linux@70fd7614 and replaced by direct flag modification * of the REQ_ flags in bio->bi_opf. Use REQ_PREFLUSH. */ static inline void bio_set_flush(struct bio *bio) { #if defined(REQ_PREFLUSH) /* >= 4.10 */ bio_set_op_attrs(bio, 0, REQ_PREFLUSH); #elif defined(WRITE_FLUSH_FUA) /* >= 2.6.37 and <= 4.9 */ bio_set_op_attrs(bio, 0, WRITE_FLUSH_FUA); #elif defined(WRITE_BARRIER) /* < 2.6.37 */ bio_set_op_attrs(bio, 0, WRITE_BARRIER); #else #error "Allowing the build will cause bio_set_flush requests to be ignored." #endif } /* * 4.8 - 4.x API, * REQ_OP_FLUSH * * 4.8-rc0 - 4.8-rc1, * REQ_PREFLUSH * * 2.6.36 - 4.7 API, * REQ_FLUSH * * 2.6.x - 2.6.35 API, * HAVE_BIO_RW_BARRIER * * Used to determine if a cache flush has been requested. This check has * been left intentionally broad in order to cover both a legacy flush * and the new preflush behavior introduced in Linux 4.8. This is correct * in all cases but may have a performance impact for some kernels. It * has the advantage of minimizing kernel specific changes in the zvol code. * */ static inline boolean_t bio_is_flush(struct bio *bio) { #if defined(HAVE_REQ_OP_FLUSH) && defined(HAVE_BIO_BI_OPF) return ((bio_op(bio) == REQ_OP_FLUSH) || (bio->bi_opf & REQ_PREFLUSH)); #elif defined(REQ_PREFLUSH) && defined(HAVE_BIO_BI_OPF) return (bio->bi_opf & REQ_PREFLUSH); #elif defined(REQ_PREFLUSH) && !defined(HAVE_BIO_BI_OPF) return (bio->bi_rw & REQ_PREFLUSH); #elif defined(REQ_FLUSH) return (bio->bi_rw & REQ_FLUSH); #elif defined(HAVE_BIO_RW_BARRIER) return (bio->bi_rw & (1 << BIO_RW_BARRIER)); #else #error "Allowing the build will cause flush requests to be ignored." #endif } /* * 4.8 - 4.x API, * REQ_FUA flag moved to bio->bi_opf * * 2.6.x - 4.7 API, * REQ_FUA */ static inline boolean_t bio_is_fua(struct bio *bio) { #if defined(HAVE_BIO_BI_OPF) return (bio->bi_opf & REQ_FUA); #elif defined(REQ_FUA) return (bio->bi_rw & REQ_FUA); #else #error "Allowing the build will cause fua requests to be ignored." #endif } /* * 4.8 - 4.x API, * REQ_OP_DISCARD * * 2.6.36 - 4.7 API, * REQ_DISCARD * * 2.6.28 - 2.6.35 API, * BIO_RW_DISCARD * * In all cases the normal I/O path is used for discards. The only * difference is how the kernel tags individual I/Os as discards. * * Note that 2.6.32 era kernels provide both BIO_RW_DISCARD and REQ_DISCARD, * where BIO_RW_DISCARD is the correct interface. Therefore, it is important * that the HAVE_BIO_RW_DISCARD check occur before the REQ_DISCARD check. */ static inline boolean_t bio_is_discard(struct bio *bio) { #if defined(HAVE_REQ_OP_DISCARD) return (bio_op(bio) == REQ_OP_DISCARD); #elif defined(HAVE_BIO_RW_DISCARD) return (bio->bi_rw & (1 << BIO_RW_DISCARD)); #elif defined(REQ_DISCARD) return (bio->bi_rw & REQ_DISCARD); #else /* potentially triggering the DMU_MAX_ACCESS assertion. */ #error "Allowing the build will cause discard requests to become writes." #endif } /* * 4.8 - 4.x API, * REQ_OP_SECURE_ERASE * * 2.6.36 - 4.7 API, * REQ_SECURE * * 2.6.x - 2.6.35 API, * Unsupported by kernel */ static inline boolean_t bio_is_secure_erase(struct bio *bio) { #if defined(HAVE_REQ_OP_SECURE_ERASE) return (bio_op(bio) == REQ_OP_SECURE_ERASE); #elif defined(REQ_SECURE) return (bio->bi_rw & REQ_SECURE); #else return (0); #endif } /* * 2.6.33 API change * Discard granularity and alignment restrictions may now be set. For * older kernels which do not support this it is safe to skip it. */ #ifdef HAVE_DISCARD_GRANULARITY static inline void blk_queue_discard_granularity(struct request_queue *q, unsigned int dg) { q->limits.discard_granularity = dg; } #else #define blk_queue_discard_granularity(x, dg) ((void)0) #endif /* HAVE_DISCARD_GRANULARITY */ /* * Default Linux IO Scheduler, * Setting the scheduler to noop will allow the Linux IO scheduler to * still perform front and back merging, while leaving the request * ordering and prioritization to the ZFS IO scheduler. */ #define VDEV_SCHEDULER "noop" /* * A common holder for vdev_bdev_open() is used to relax the exclusive open * semantics slightly. Internal vdev disk callers may pass VDEV_HOLDER to * allow them to open the device multiple times. Other kernel callers and * user space processes which don't pass this value will get EBUSY. This is * currently required for the correct operation of hot spares. */ #define VDEV_HOLDER ((void *)0x2401de7) static inline void blk_generic_start_io_acct(struct request_queue *q, int rw, unsigned long sectors, struct hd_struct *part) { #if defined(HAVE_GENERIC_IO_ACCT_3ARG) generic_start_io_acct(rw, sectors, part); #elif defined(HAVE_GENERIC_IO_ACCT_4ARG) generic_start_io_acct(q, rw, sectors, part); #endif } static inline void blk_generic_end_io_acct(struct request_queue *q, int rw, struct hd_struct *part, unsigned long start_time) { #if defined(HAVE_GENERIC_IO_ACCT_3ARG) generic_end_io_acct(rw, part, start_time); #elif defined(HAVE_GENERIC_IO_ACCT_4ARG) generic_end_io_acct(q, rw, part, start_time); #endif } #endif /* _ZFS_BLKDEV_H */