diff --git a/config/kernel-bio.m4 b/config/kernel-bio.m4 index 0c533531dceb..d8692bd39999 100644 --- a/config/kernel-bio.m4 +++ b/config/kernel-bio.m4 @@ -1,403 +1,432 @@ dnl # dnl # 2.6.36 API change, dnl # REQ_FAILFAST_{DEV|TRANSPORT|DRIVER} dnl # REQ_DISCARD dnl # REQ_FLUSH dnl # dnl # 4.8 - 4.9 API, dnl # REQ_FLUSH was renamed to REQ_PREFLUSH dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_REQ], [ ZFS_LINUX_TEST_SRC([req_failfast_mask], [ #include ],[ int flags __attribute__ ((unused)); flags = REQ_FAILFAST_MASK; ]) ZFS_LINUX_TEST_SRC([req_discard], [ #include ],[ int flags __attribute__ ((unused)); flags = REQ_DISCARD; ]) ZFS_LINUX_TEST_SRC([req_flush], [ #include ],[ int flags __attribute__ ((unused)); flags = REQ_FLUSH; ]) ZFS_LINUX_TEST_SRC([req_preflush], [ #include ],[ int flags __attribute__ ((unused)); flags = REQ_PREFLUSH; ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_FAILFAST_MASK], [ AC_MSG_CHECKING([whether REQ_FAILFAST_MASK is defined]) ZFS_LINUX_TEST_RESULT([req_failfast_mask], [ AC_MSG_RESULT(yes) ],[ ZFS_LINUX_TEST_ERROR([REQ_FAILFAST_MASK]) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_DISCARD], [ AC_MSG_CHECKING([whether REQ_DISCARD is defined]) ZFS_LINUX_TEST_RESULT([req_discard], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_DISCARD, 1, [REQ_DISCARD is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_FLUSH], [ AC_MSG_CHECKING([whether REQ_FLUSH is defined]) ZFS_LINUX_TEST_RESULT([req_flush], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_FLUSH, 1, [REQ_FLUSH is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_PREFLUSH], [ AC_MSG_CHECKING([whether REQ_PREFLUSH is defined]) ZFS_LINUX_TEST_RESULT([req_preflush], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_PREFLUSH, 1, [REQ_PREFLUSH is defined]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # Linux 4.8 API, dnl # dnl # The bio_op() helper was introduced as a replacement for explicitly dnl # checking the bio->bi_rw flags. The following checks are used to dnl # detect if a specific operation is supported. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_OPS], [ ZFS_LINUX_TEST_SRC([req_op_discard], [ #include ],[ int op __attribute__ ((unused)) = REQ_OP_DISCARD; ]) ZFS_LINUX_TEST_SRC([req_op_secure_erase], [ #include ],[ int op __attribute__ ((unused)) = REQ_OP_SECURE_ERASE; ]) ZFS_LINUX_TEST_SRC([req_op_flush], [ #include ],[ int op __attribute__ ((unused)) = REQ_OP_FLUSH; ]) ZFS_LINUX_TEST_SRC([bio_bi_opf], [ #include ],[ struct bio bio __attribute__ ((unused)); bio.bi_opf = 0; ]) ZFS_LINUX_TEST_SRC([bio_set_op_attrs], [ #include ],[ struct bio *bio __attribute__ ((unused)) = NULL; bio_set_op_attrs(bio, 0, 0); ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_OP_DISCARD], [ AC_MSG_CHECKING([whether REQ_OP_DISCARD is defined]) ZFS_LINUX_TEST_RESULT([req_op_discard], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_OP_DISCARD, 1, [REQ_OP_DISCARD is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_OP_SECURE_ERASE], [ AC_MSG_CHECKING([whether REQ_OP_SECURE_ERASE is defined]) ZFS_LINUX_TEST_RESULT([req_op_secure_erase], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_OP_SECURE_ERASE, 1, [REQ_OP_SECURE_ERASE is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_REQ_OP_FLUSH], [ AC_MSG_CHECKING([whether REQ_OP_FLUSH is defined]) ZFS_LINUX_TEST_RESULT([req_op_flush], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_REQ_OP_FLUSH, 1, [REQ_OP_FLUSH is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_BI_OPF], [ AC_MSG_CHECKING([whether bio->bi_opf is defined]) ZFS_LINUX_TEST_RESULT([bio_bi_opf], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_BI_OPF, 1, [bio->bi_opf is defined]) ],[ AC_MSG_RESULT(no) ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_SET_OP_ATTRS], [ AC_MSG_CHECKING([whether bio_set_op_attrs is available]) ZFS_LINUX_TEST_RESULT([bio_set_op_attrs], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_SET_OP_ATTRS, 1, [bio_set_op_attrs is available]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # Linux 4.14 API, dnl # dnl # The bio_set_dev() helper macro was introduced as part of the transition dnl # to have struct gendisk in struct bio. dnl # dnl # Linux 5.0 API, dnl # dnl # The bio_set_dev() helper macro was updated to internally depend on dnl # bio_associate_blkg() symbol which is exported GPL-only. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_SET_DEV], [ ZFS_LINUX_TEST_SRC([bio_set_dev], [ #include #include ],[ struct block_device *bdev = NULL; struct bio *bio = NULL; bio_set_dev(bio, bdev); ], [], [ZFS_META_LICENSE]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_SET_DEV], [ AC_MSG_CHECKING([whether bio_set_dev() is available]) ZFS_LINUX_TEST_RESULT([bio_set_dev], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_SET_DEV, 1, [bio_set_dev() is available]) AC_MSG_CHECKING([whether bio_set_dev() is GPL-only]) ZFS_LINUX_TEST_RESULT([bio_set_dev_license], [ AC_MSG_RESULT(no) ],[ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_SET_DEV_GPL_ONLY, 1, [bio_set_dev() GPL-only]) ]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # 4.3 API change dnl # Error argument dropped from bio_endio in favor of newly introduced dnl # bio->bi_error. This also replaces bio->bi_flags value BIO_UPTODATE. dnl # Introduced by torvalds/linux@4246a0b63bd8f56a1469b12eafeb875b1041a451 dnl # ("block: add a bi_error field to struct bio"). dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_END_IO_T_ARGS], [ ZFS_LINUX_TEST_SRC([bio_end_io_t_args], [ #include void wanted_end_io(struct bio *bio) { return; } bio_end_io_t *end_io __attribute__ ((unused)) = wanted_end_io; ], []) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_END_IO_T_ARGS], [ AC_MSG_CHECKING([whether bio_end_io_t wants 1 arg]) ZFS_LINUX_TEST_RESULT([bio_end_io_t_args], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_1ARG_BIO_END_IO_T, 1, [bio_end_io_t wants 1 arg]) ], [ AC_MSG_RESULT(no) ]) ]) dnl # dnl # 4.13 API change dnl # The bio->bi_error field was replaced with bio->bi_status which is an dnl # enum which describes all possible error types. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_BI_STATUS], [ ZFS_LINUX_TEST_SRC([bio_bi_status], [ #include ], [ struct bio bio __attribute__ ((unused)); blk_status_t status __attribute__ ((unused)) = BLK_STS_OK; bio.bi_status = status; ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_BI_STATUS], [ AC_MSG_CHECKING([whether bio->bi_status exists]) ZFS_LINUX_TEST_RESULT([bio_bi_status], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_BI_STATUS, 1, [bio->bi_status exists]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # 3.14 API change, dnl # Immutable biovecs. A number of fields of struct bio are moved to dnl # struct bvec_iter. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_BVEC_ITER], [ ZFS_LINUX_TEST_SRC([bio_bvec_iter], [ #include ],[ struct bio bio; bio.bi_iter.bi_sector = 0; ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_BVEC_ITER], [ AC_MSG_CHECKING([whether bio has bi_iter]) ZFS_LINUX_TEST_RESULT([bio_bvec_iter], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BIO_BVEC_ITER, 1, [bio has bi_iter]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # 4.8 API change dnl # The rw argument has been removed from submit_bio/submit_bio_wait. dnl # Callers are now expected to set bio->bi_rw instead of passing it in. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_SUBMIT_BIO], [ ZFS_LINUX_TEST_SRC([submit_bio], [ #include ],[ blk_qc_t blk_qc; struct bio *bio = NULL; blk_qc = submit_bio(bio); ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_SUBMIT_BIO], [ AC_MSG_CHECKING([whether submit_bio() wants 1 arg]) ZFS_LINUX_TEST_RESULT([submit_bio], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_1ARG_SUBMIT_BIO, 1, [submit_bio() wants 1 arg]) ],[ AC_MSG_RESULT(no) ]) ]) dnl # dnl # 2.6.34 API change dnl # current->bio_list dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_CURRENT_BIO_LIST], [ ZFS_LINUX_TEST_SRC([current_bio_list], [ #include ], [ current->bio_list = (struct bio_list *) NULL; ]) ]) AC_DEFUN([ZFS_AC_KERNEL_BIO_CURRENT_BIO_LIST], [ AC_MSG_CHECKING([whether current->bio_list exists]) ZFS_LINUX_TEST_RESULT([current_bio_list], [ AC_MSG_RESULT(yes) ],[ ZFS_LINUX_TEST_ERROR([bio_list]) ]) ]) dnl # dnl # Linux 5.5 API, dnl # dnl # The Linux 5.5 kernel updated percpu_ref_tryget() which is inlined by dnl # blkg_tryget() to use rcu_read_lock() instead of rcu_read_lock_sched(). dnl # As a side effect the function was converted to GPL-only. dnl # AC_DEFUN([ZFS_AC_KERNEL_SRC_BLKG_TRYGET], [ ZFS_LINUX_TEST_SRC([blkg_tryget], [ #include #include #include ],[ struct blkcg_gq blkg __attribute__ ((unused)) = {}; bool rc __attribute__ ((unused)); rc = blkg_tryget(&blkg); ], [], [ZFS_META_LICENSE]) ]) AC_DEFUN([ZFS_AC_KERNEL_BLKG_TRYGET], [ AC_MSG_CHECKING([whether blkg_tryget() is available]) ZFS_LINUX_TEST_RESULT([blkg_tryget], [ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BLKG_TRYGET, 1, [blkg_tryget() is available]) AC_MSG_CHECKING([whether blkg_tryget() is GPL-only]) ZFS_LINUX_TEST_RESULT([blkg_tryget_license], [ AC_MSG_RESULT(no) ],[ AC_MSG_RESULT(yes) AC_DEFINE(HAVE_BLKG_TRYGET_GPL_ONLY, 1, [blkg_tryget() GPL-only]) ]) ],[ AC_MSG_RESULT(no) ]) ]) +dnl # +dnl # Linux 5.12 API, +dnl # +dnl # The Linux 5.12 kernel updated struct bio to create a new bi_bdev member +dnl # and bio->bi_disk was moved to bio->bi_bdev->bd_disk +dnl # +AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO_BDEV_DISK], [ + ZFS_LINUX_TEST_SRC([bio_bdev_disk], [ + #include + #include + ],[ + struct bio *b = NULL; + struct gendisk *d = b->bi_bdev->bd_disk; + blk_register_queue(d); + ]) +]) + +AC_DEFUN([ZFS_AC_KERNEL_BIO_BDEV_DISK], [ + AC_MSG_CHECKING([whether bio->bi_bdev->bd_disk exists]) + ZFS_LINUX_TEST_RESULT([bio_bdev_disk], [ + AC_MSG_RESULT(yes) + AC_DEFINE(HAVE_BIO_BDEV_DISK, 1, [bio->bi_bdev->bd_disk exists]) + ],[ + AC_MSG_RESULT(no) + ]) +]) + AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO], [ ZFS_AC_KERNEL_SRC_REQ ZFS_AC_KERNEL_SRC_BIO_OPS ZFS_AC_KERNEL_SRC_BIO_SET_DEV ZFS_AC_KERNEL_SRC_BIO_END_IO_T_ARGS ZFS_AC_KERNEL_SRC_BIO_BI_STATUS ZFS_AC_KERNEL_SRC_BIO_BVEC_ITER ZFS_AC_KERNEL_SRC_BIO_SUBMIT_BIO ZFS_AC_KERNEL_SRC_BIO_CURRENT_BIO_LIST ZFS_AC_KERNEL_SRC_BLKG_TRYGET + ZFS_AC_KERNEL_SRC_BIO_BDEV_DISK ]) AC_DEFUN([ZFS_AC_KERNEL_BIO], [ ZFS_AC_KERNEL_BIO_REQ_FAILFAST_MASK ZFS_AC_KERNEL_BIO_REQ_DISCARD ZFS_AC_KERNEL_BIO_REQ_FLUSH ZFS_AC_KERNEL_BIO_REQ_PREFLUSH ZFS_AC_KERNEL_BIO_REQ_OP_DISCARD ZFS_AC_KERNEL_BIO_REQ_OP_SECURE_ERASE ZFS_AC_KERNEL_BIO_REQ_OP_FLUSH ZFS_AC_KERNEL_BIO_BI_OPF ZFS_AC_KERNEL_BIO_SET_OP_ATTRS ZFS_AC_KERNEL_BIO_SET_DEV ZFS_AC_KERNEL_BIO_END_IO_T_ARGS ZFS_AC_KERNEL_BIO_BI_STATUS ZFS_AC_KERNEL_BIO_BVEC_ITER ZFS_AC_KERNEL_BIO_SUBMIT_BIO ZFS_AC_KERNEL_BIO_CURRENT_BIO_LIST ZFS_AC_KERNEL_BLKG_TRYGET + ZFS_AC_KERNEL_BIO_BDEV_DISK ]) diff --git a/module/os/linux/zfs/vdev_disk.c b/module/os/linux/zfs/vdev_disk.c index b373f2c2e83c..ff71ef4cd065 100644 --- a/module/os/linux/zfs/vdev_disk.c +++ b/module/os/linux/zfs/vdev_disk.c @@ -1,919 +1,923 @@ /* * 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) 2008-2010 Lawrence Livermore National Security, LLC. * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). * Rewritten for Linux by Brian Behlendorf . * LLNL-CODE-403049. * Copyright (c) 2012, 2019 by Delphix. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include typedef struct vdev_disk { struct block_device *vd_bdev; krwlock_t vd_lock; } vdev_disk_t; /* * Unique identifier for the exclusive vdev holder. */ static void *zfs_vdev_holder = VDEV_HOLDER; /* * Wait up to zfs_vdev_open_timeout_ms milliseconds before determining the * device is missing. The missing path may be transient since the links * can be briefly removed and recreated in response to udev events. */ static unsigned zfs_vdev_open_timeout_ms = 1000; /* * Size of the "reserved" partition, in blocks. */ #define EFI_MIN_RESV_SIZE (16 * 1024) /* * Virtual device vector for disks. */ typedef struct dio_request { zio_t *dr_zio; /* Parent ZIO */ atomic_t dr_ref; /* References */ int dr_error; /* Bio error */ int dr_bio_count; /* Count of bio's */ struct bio *dr_bio[0]; /* Attached bio's */ } dio_request_t; static fmode_t vdev_bdev_mode(spa_mode_t spa_mode) { fmode_t mode = 0; if (spa_mode & SPA_MODE_READ) mode |= FMODE_READ; if (spa_mode & SPA_MODE_WRITE) mode |= FMODE_WRITE; return (mode); } /* * Returns the usable capacity (in bytes) for the partition or disk. */ static uint64_t bdev_capacity(struct block_device *bdev) { return (i_size_read(bdev->bd_inode)); } #if !defined(HAVE_BDEV_WHOLE) static inline struct block_device * bdev_whole(struct block_device *bdev) { return (bdev->bd_contains); } #endif /* * Returns the maximum expansion capacity of the block device (in bytes). * * It is possible to expand a vdev when it has been created as a wholedisk * and the containing block device has increased in capacity. Or when the * partition containing the pool has been manually increased in size. * * This function is only responsible for calculating the potential expansion * size so it can be reported by 'zpool list'. The efi_use_whole_disk() is * responsible for verifying the expected partition layout in the wholedisk * case, and updating the partition table if appropriate. Once the partition * size has been increased the additional capacity will be visible using * bdev_capacity(). * * The returned maximum expansion capacity is always expected to be larger, or * at the very least equal, to its usable capacity to prevent overestimating * the pool expandsize. */ static uint64_t bdev_max_capacity(struct block_device *bdev, uint64_t wholedisk) { uint64_t psize; int64_t available; if (wholedisk && bdev != bdev_whole(bdev)) { /* * When reporting maximum expansion capacity for a wholedisk * deduct any capacity which is expected to be lost due to * alignment restrictions. Over reporting this value isn't * harmful and would only result in slightly less capacity * than expected post expansion. * The estimated available space may be slightly smaller than * bdev_capacity() for devices where the number of sectors is * not a multiple of the alignment size and the partition layout * is keeping less than PARTITION_END_ALIGNMENT bytes after the * "reserved" EFI partition: in such cases return the device * usable capacity. */ available = i_size_read(bdev_whole(bdev)->bd_inode) - ((EFI_MIN_RESV_SIZE + NEW_START_BLOCK + PARTITION_END_ALIGNMENT) << SECTOR_BITS); psize = MAX(available, bdev_capacity(bdev)); } else { psize = bdev_capacity(bdev); } return (psize); } static void vdev_disk_error(zio_t *zio) { /* * This function can be called in interrupt context, for instance while * handling IRQs coming from a misbehaving disk device; use printk() * which is safe from any context. */ printk(KERN_WARNING "zio pool=%s vdev=%s error=%d type=%d " "offset=%llu size=%llu flags=%x\n", spa_name(zio->io_spa), zio->io_vd->vdev_path, zio->io_error, zio->io_type, (u_longlong_t)zio->io_offset, (u_longlong_t)zio->io_size, zio->io_flags); } static int vdev_disk_open(vdev_t *v, uint64_t *psize, uint64_t *max_psize, uint64_t *logical_ashift, uint64_t *physical_ashift) { struct block_device *bdev; fmode_t mode = vdev_bdev_mode(spa_mode(v->vdev_spa)); hrtime_t timeout = MSEC2NSEC(zfs_vdev_open_timeout_ms); vdev_disk_t *vd; /* Must have a pathname and it must be absolute. */ if (v->vdev_path == NULL || v->vdev_path[0] != '/') { v->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; vdev_dbgmsg(v, "invalid vdev_path"); return (SET_ERROR(EINVAL)); } /* * Reopen the device if it is currently open. When expanding a * partition force re-scanning the partition table if userland * did not take care of this already. We need to do this while closed * in order to get an accurate updated block device size. Then * since udev may need to recreate the device links increase the * open retry timeout before reporting the device as unavailable. */ vd = v->vdev_tsd; if (vd) { char disk_name[BDEVNAME_SIZE + 6] = "/dev/"; boolean_t reread_part = B_FALSE; rw_enter(&vd->vd_lock, RW_WRITER); bdev = vd->vd_bdev; vd->vd_bdev = NULL; if (bdev) { if (v->vdev_expanding && bdev != bdev_whole(bdev)) { bdevname(bdev_whole(bdev), disk_name + 5); /* * If userland has BLKPG_RESIZE_PARTITION, * then it should have updated the partition * table already. We can detect this by * comparing our current physical size * with that of the device. If they are * the same, then we must not have * BLKPG_RESIZE_PARTITION or it failed to * update the partition table online. We * fallback to rescanning the partition * table from the kernel below. However, * if the capacity already reflects the * updated partition, then we skip * rescanning the partition table here. */ if (v->vdev_psize == bdev_capacity(bdev)) reread_part = B_TRUE; } blkdev_put(bdev, mode | FMODE_EXCL); } if (reread_part) { bdev = blkdev_get_by_path(disk_name, mode | FMODE_EXCL, zfs_vdev_holder); if (!IS_ERR(bdev)) { int error = vdev_bdev_reread_part(bdev); blkdev_put(bdev, mode | FMODE_EXCL); if (error == 0) { timeout = MSEC2NSEC( zfs_vdev_open_timeout_ms * 2); } } } } else { vd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP); rw_init(&vd->vd_lock, NULL, RW_DEFAULT, NULL); rw_enter(&vd->vd_lock, RW_WRITER); } /* * Devices are always opened by the path provided at configuration * time. This means that if the provided path is a udev by-id path * then drives may be re-cabled without an issue. If the provided * path is a udev by-path path, then the physical location information * will be preserved. This can be critical for more complicated * configurations where drives are located in specific physical * locations to maximize the systems tolerance to component failure. * * Alternatively, you can provide your own udev rule to flexibly map * the drives as you see fit. It is not advised that you use the * /dev/[hd]d devices which may be reordered due to probing order. * Devices in the wrong locations will be detected by the higher * level vdev validation. * * The specified paths may be briefly removed and recreated in * response to udev events. This should be exceptionally unlikely * because the zpool command makes every effort to verify these paths * have already settled prior to reaching this point. Therefore, * a ENOENT failure at this point is highly likely to be transient * and it is reasonable to sleep and retry before giving up. In * practice delays have been observed to be on the order of 100ms. */ hrtime_t start = gethrtime(); bdev = ERR_PTR(-ENXIO); while (IS_ERR(bdev) && ((gethrtime() - start) < timeout)) { bdev = blkdev_get_by_path(v->vdev_path, mode | FMODE_EXCL, zfs_vdev_holder); if (unlikely(PTR_ERR(bdev) == -ENOENT)) { schedule_timeout(MSEC_TO_TICK(10)); } else if (IS_ERR(bdev)) { break; } } if (IS_ERR(bdev)) { int error = -PTR_ERR(bdev); vdev_dbgmsg(v, "open error=%d timeout=%llu/%llu", error, (u_longlong_t)(gethrtime() - start), (u_longlong_t)timeout); vd->vd_bdev = NULL; v->vdev_tsd = vd; rw_exit(&vd->vd_lock); return (SET_ERROR(error)); } else { vd->vd_bdev = bdev; v->vdev_tsd = vd; rw_exit(&vd->vd_lock); } struct request_queue *q = bdev_get_queue(vd->vd_bdev); /* Determine the physical block size */ int physical_block_size = bdev_physical_block_size(vd->vd_bdev); /* Determine the logical block size */ int logical_block_size = bdev_logical_block_size(vd->vd_bdev); /* Clear the nowritecache bit, causes vdev_reopen() to try again. */ v->vdev_nowritecache = B_FALSE; /* Set when device reports it supports TRIM. */ v->vdev_has_trim = !!blk_queue_discard(q); /* Set when device reports it supports secure TRIM. */ v->vdev_has_securetrim = !!blk_queue_discard_secure(q); /* Inform the ZIO pipeline that we are non-rotational */ v->vdev_nonrot = blk_queue_nonrot(q); /* Physical volume size in bytes for the partition */ *psize = bdev_capacity(vd->vd_bdev); /* Physical volume size in bytes including possible expansion space */ *max_psize = bdev_max_capacity(vd->vd_bdev, v->vdev_wholedisk); /* Based on the minimum sector size set the block size */ *physical_ashift = highbit64(MAX(physical_block_size, SPA_MINBLOCKSIZE)) - 1; *logical_ashift = highbit64(MAX(logical_block_size, SPA_MINBLOCKSIZE)) - 1; return (0); } static void vdev_disk_close(vdev_t *v) { vdev_disk_t *vd = v->vdev_tsd; if (v->vdev_reopening || vd == NULL) return; if (vd->vd_bdev != NULL) { blkdev_put(vd->vd_bdev, vdev_bdev_mode(spa_mode(v->vdev_spa)) | FMODE_EXCL); } rw_destroy(&vd->vd_lock); kmem_free(vd, sizeof (vdev_disk_t)); v->vdev_tsd = NULL; } static dio_request_t * vdev_disk_dio_alloc(int bio_count) { dio_request_t *dr = kmem_zalloc(sizeof (dio_request_t) + sizeof (struct bio *) * bio_count, KM_SLEEP); atomic_set(&dr->dr_ref, 0); dr->dr_bio_count = bio_count; dr->dr_error = 0; for (int i = 0; i < dr->dr_bio_count; i++) dr->dr_bio[i] = NULL; return (dr); } static void vdev_disk_dio_free(dio_request_t *dr) { int i; for (i = 0; i < dr->dr_bio_count; i++) if (dr->dr_bio[i]) bio_put(dr->dr_bio[i]); kmem_free(dr, sizeof (dio_request_t) + sizeof (struct bio *) * dr->dr_bio_count); } static void vdev_disk_dio_get(dio_request_t *dr) { atomic_inc(&dr->dr_ref); } static int vdev_disk_dio_put(dio_request_t *dr) { int rc = atomic_dec_return(&dr->dr_ref); /* * Free the dio_request when the last reference is dropped and * ensure zio_interpret is called only once with the correct zio */ if (rc == 0) { zio_t *zio = dr->dr_zio; int error = dr->dr_error; vdev_disk_dio_free(dr); if (zio) { zio->io_error = error; ASSERT3S(zio->io_error, >=, 0); if (zio->io_error) vdev_disk_error(zio); zio_delay_interrupt(zio); } } return (rc); } BIO_END_IO_PROTO(vdev_disk_physio_completion, bio, error) { dio_request_t *dr = bio->bi_private; int rc; if (dr->dr_error == 0) { #ifdef HAVE_1ARG_BIO_END_IO_T dr->dr_error = BIO_END_IO_ERROR(bio); #else if (error) dr->dr_error = -(error); else if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) dr->dr_error = EIO; #endif } /* Drop reference acquired by __vdev_disk_physio */ rc = vdev_disk_dio_put(dr); } static inline void vdev_submit_bio_impl(struct bio *bio) { #ifdef HAVE_1ARG_SUBMIT_BIO submit_bio(bio); #else submit_bio(0, bio); #endif } /* * preempt_schedule_notrace is GPL-only which breaks the ZFS build, so * replace it with preempt_schedule under the following condition: */ #if defined(CONFIG_ARM64) && \ defined(CONFIG_PREEMPTION) && \ defined(CONFIG_BLK_CGROUP) #define preempt_schedule_notrace(x) preempt_schedule(x) #endif #ifdef HAVE_BIO_SET_DEV #if defined(CONFIG_BLK_CGROUP) && defined(HAVE_BIO_SET_DEV_GPL_ONLY) /* * The Linux 5.5 kernel updated percpu_ref_tryget() which is inlined by * blkg_tryget() to use rcu_read_lock() instead of rcu_read_lock_sched(). * As a side effect the function was converted to GPL-only. Define our * own version when needed which uses rcu_read_lock_sched(). */ #if defined(HAVE_BLKG_TRYGET_GPL_ONLY) static inline bool vdev_blkg_tryget(struct blkcg_gq *blkg) { struct percpu_ref *ref = &blkg->refcnt; unsigned long __percpu *count; bool rc; rcu_read_lock_sched(); if (__ref_is_percpu(ref, &count)) { this_cpu_inc(*count); rc = true; } else { #ifdef ZFS_PERCPU_REF_COUNT_IN_DATA rc = atomic_long_inc_not_zero(&ref->data->count); #else rc = atomic_long_inc_not_zero(&ref->count); #endif } rcu_read_unlock_sched(); return (rc); } #elif defined(HAVE_BLKG_TRYGET) #define vdev_blkg_tryget(bg) blkg_tryget(bg) #endif /* * The Linux 5.0 kernel updated the bio_set_dev() macro so it calls the * GPL-only bio_associate_blkg() symbol thus inadvertently converting * the entire macro. Provide a minimal version which always assigns the * request queue's root_blkg to the bio. */ static inline void vdev_bio_associate_blkg(struct bio *bio) { +#if defined(HAVE_BIO_BDEV_DISK) + struct request_queue *q = bio->bi_bdev->bd_disk->queue; +#else struct request_queue *q = bio->bi_disk->queue; +#endif ASSERT3P(q, !=, NULL); ASSERT3P(bio->bi_blkg, ==, NULL); if (q->root_blkg && vdev_blkg_tryget(q->root_blkg)) bio->bi_blkg = q->root_blkg; } #define bio_associate_blkg vdev_bio_associate_blkg #endif #else /* * Provide a bio_set_dev() helper macro for pre-Linux 4.14 kernels. */ static inline void bio_set_dev(struct bio *bio, struct block_device *bdev) { bio->bi_bdev = bdev; } #endif /* HAVE_BIO_SET_DEV */ static inline void vdev_submit_bio(struct bio *bio) { struct bio_list *bio_list = current->bio_list; current->bio_list = NULL; vdev_submit_bio_impl(bio); current->bio_list = bio_list; } static int __vdev_disk_physio(struct block_device *bdev, zio_t *zio, size_t io_size, uint64_t io_offset, int rw, int flags) { dio_request_t *dr; uint64_t abd_offset; uint64_t bio_offset; int bio_size; int bio_count = 16; int error = 0; struct blk_plug plug; /* * Accessing outside the block device is never allowed. */ if (io_offset + io_size > bdev->bd_inode->i_size) { vdev_dbgmsg(zio->io_vd, "Illegal access %llu size %llu, device size %llu", io_offset, io_size, i_size_read(bdev->bd_inode)); return (SET_ERROR(EIO)); } retry: dr = vdev_disk_dio_alloc(bio_count); if (zio && !(zio->io_flags & (ZIO_FLAG_IO_RETRY | ZIO_FLAG_TRYHARD))) bio_set_flags_failfast(bdev, &flags); dr->dr_zio = zio; /* * Since bio's can have up to BIO_MAX_PAGES=256 iovec's, each of which * is at least 512 bytes and at most PAGESIZE (typically 4K), one bio * can cover at least 128KB and at most 1MB. When the required number * of iovec's exceeds this, we are forced to break the IO in multiple * bio's and wait for them all to complete. This is likely if the * recordsize property is increased beyond 1MB. The default * bio_count=16 should typically accommodate the maximum-size zio of * 16MB. */ abd_offset = 0; bio_offset = io_offset; bio_size = io_size; for (int i = 0; i <= dr->dr_bio_count; i++) { /* Finished constructing bio's for given buffer */ if (bio_size <= 0) break; /* * If additional bio's are required, we have to retry, but * this should be rare - see the comment above. */ if (dr->dr_bio_count == i) { vdev_disk_dio_free(dr); bio_count *= 2; goto retry; } /* bio_alloc() with __GFP_WAIT never returns NULL */ dr->dr_bio[i] = bio_alloc(GFP_NOIO, MIN(abd_nr_pages_off(zio->io_abd, bio_size, abd_offset), BIO_MAX_PAGES)); if (unlikely(dr->dr_bio[i] == NULL)) { vdev_disk_dio_free(dr); return (SET_ERROR(ENOMEM)); } /* Matching put called by vdev_disk_physio_completion */ vdev_disk_dio_get(dr); bio_set_dev(dr->dr_bio[i], bdev); BIO_BI_SECTOR(dr->dr_bio[i]) = bio_offset >> 9; dr->dr_bio[i]->bi_end_io = vdev_disk_physio_completion; dr->dr_bio[i]->bi_private = dr; bio_set_op_attrs(dr->dr_bio[i], rw, flags); /* Remaining size is returned to become the new size */ bio_size = abd_bio_map_off(dr->dr_bio[i], zio->io_abd, bio_size, abd_offset); /* Advance in buffer and construct another bio if needed */ abd_offset += BIO_BI_SIZE(dr->dr_bio[i]); bio_offset += BIO_BI_SIZE(dr->dr_bio[i]); } /* Extra reference to protect dio_request during vdev_submit_bio */ vdev_disk_dio_get(dr); if (dr->dr_bio_count > 1) blk_start_plug(&plug); /* Submit all bio's associated with this dio */ for (int i = 0; i < dr->dr_bio_count; i++) { if (dr->dr_bio[i]) vdev_submit_bio(dr->dr_bio[i]); } if (dr->dr_bio_count > 1) blk_finish_plug(&plug); (void) vdev_disk_dio_put(dr); return (error); } BIO_END_IO_PROTO(vdev_disk_io_flush_completion, bio, error) { zio_t *zio = bio->bi_private; #ifdef HAVE_1ARG_BIO_END_IO_T zio->io_error = BIO_END_IO_ERROR(bio); #else zio->io_error = -error; #endif if (zio->io_error && (zio->io_error == EOPNOTSUPP)) zio->io_vd->vdev_nowritecache = B_TRUE; bio_put(bio); ASSERT3S(zio->io_error, >=, 0); if (zio->io_error) vdev_disk_error(zio); zio_interrupt(zio); } static int vdev_disk_io_flush(struct block_device *bdev, zio_t *zio) { struct request_queue *q; struct bio *bio; q = bdev_get_queue(bdev); if (!q) return (SET_ERROR(ENXIO)); bio = bio_alloc(GFP_NOIO, 0); /* bio_alloc() with __GFP_WAIT never returns NULL */ if (unlikely(bio == NULL)) return (SET_ERROR(ENOMEM)); bio->bi_end_io = vdev_disk_io_flush_completion; bio->bi_private = zio; bio_set_dev(bio, bdev); bio_set_flush(bio); vdev_submit_bio(bio); invalidate_bdev(bdev); return (0); } static void vdev_disk_io_start(zio_t *zio) { vdev_t *v = zio->io_vd; vdev_disk_t *vd = v->vdev_tsd; unsigned long trim_flags = 0; int rw, error; /* * If the vdev is closed, it's likely in the REMOVED or FAULTED state. * Nothing to be done here but return failure. */ if (vd == NULL) { zio->io_error = ENXIO; zio_interrupt(zio); return; } rw_enter(&vd->vd_lock, RW_READER); /* * If the vdev is closed, it's likely due to a failed reopen and is * in the UNAVAIL state. Nothing to be done here but return failure. */ if (vd->vd_bdev == NULL) { rw_exit(&vd->vd_lock); zio->io_error = ENXIO; zio_interrupt(zio); return; } switch (zio->io_type) { case ZIO_TYPE_IOCTL: if (!vdev_readable(v)) { rw_exit(&vd->vd_lock); zio->io_error = SET_ERROR(ENXIO); zio_interrupt(zio); return; } switch (zio->io_cmd) { case DKIOCFLUSHWRITECACHE: if (zfs_nocacheflush) break; if (v->vdev_nowritecache) { zio->io_error = SET_ERROR(ENOTSUP); break; } error = vdev_disk_io_flush(vd->vd_bdev, zio); if (error == 0) { rw_exit(&vd->vd_lock); return; } zio->io_error = error; break; default: zio->io_error = SET_ERROR(ENOTSUP); } rw_exit(&vd->vd_lock); zio_execute(zio); return; case ZIO_TYPE_WRITE: rw = WRITE; break; case ZIO_TYPE_READ: rw = READ; break; case ZIO_TYPE_TRIM: #if defined(BLKDEV_DISCARD_SECURE) if (zio->io_trim_flags & ZIO_TRIM_SECURE) trim_flags |= BLKDEV_DISCARD_SECURE; #endif zio->io_error = -blkdev_issue_discard(vd->vd_bdev, zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS, trim_flags); rw_exit(&vd->vd_lock); zio_interrupt(zio); return; default: rw_exit(&vd->vd_lock); zio->io_error = SET_ERROR(ENOTSUP); zio_interrupt(zio); return; } zio->io_target_timestamp = zio_handle_io_delay(zio); error = __vdev_disk_physio(vd->vd_bdev, zio, zio->io_size, zio->io_offset, rw, 0); rw_exit(&vd->vd_lock); if (error) { zio->io_error = error; zio_interrupt(zio); return; } } static void vdev_disk_io_done(zio_t *zio) { /* * If the device returned EIO, we revalidate the media. If it is * determined the media has changed this triggers the asynchronous * removal of the device from the configuration. */ if (zio->io_error == EIO) { vdev_t *v = zio->io_vd; vdev_disk_t *vd = v->vdev_tsd; if (zfs_check_media_change(vd->vd_bdev)) { invalidate_bdev(vd->vd_bdev); v->vdev_remove_wanted = B_TRUE; spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE); } } } static void vdev_disk_hold(vdev_t *vd) { ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER)); /* We must have a pathname, and it must be absolute. */ if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') return; /* * Only prefetch path and devid info if the device has * never been opened. */ if (vd->vdev_tsd != NULL) return; } static void vdev_disk_rele(vdev_t *vd) { ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER)); /* XXX: Implement me as a vnode rele for the device */ } vdev_ops_t vdev_disk_ops = { .vdev_op_init = NULL, .vdev_op_fini = NULL, .vdev_op_open = vdev_disk_open, .vdev_op_close = vdev_disk_close, .vdev_op_asize = vdev_default_asize, .vdev_op_min_asize = vdev_default_min_asize, .vdev_op_min_alloc = NULL, .vdev_op_io_start = vdev_disk_io_start, .vdev_op_io_done = vdev_disk_io_done, .vdev_op_state_change = NULL, .vdev_op_need_resilver = NULL, .vdev_op_hold = vdev_disk_hold, .vdev_op_rele = vdev_disk_rele, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_default_xlate, .vdev_op_rebuild_asize = NULL, .vdev_op_metaslab_init = NULL, .vdev_op_config_generate = NULL, .vdev_op_nparity = NULL, .vdev_op_ndisks = NULL, .vdev_op_type = VDEV_TYPE_DISK, /* name of this vdev type */ .vdev_op_leaf = B_TRUE /* leaf vdev */ }; /* * The zfs_vdev_scheduler module option has been deprecated. Setting this * value no longer has any effect. It has not yet been entirely removed * to allow the module to be loaded if this option is specified in the * /etc/modprobe.d/zfs.conf file. The following warning will be logged. */ static int param_set_vdev_scheduler(const char *val, zfs_kernel_param_t *kp) { int error = param_set_charp(val, kp); if (error == 0) { printk(KERN_INFO "The 'zfs_vdev_scheduler' module option " "is not supported.\n"); } return (error); } char *zfs_vdev_scheduler = "unused"; module_param_call(zfs_vdev_scheduler, param_set_vdev_scheduler, param_get_charp, &zfs_vdev_scheduler, 0644); MODULE_PARM_DESC(zfs_vdev_scheduler, "I/O scheduler"); int param_set_min_auto_ashift(const char *buf, zfs_kernel_param_t *kp) { uint64_t val; int error; error = kstrtoull(buf, 0, &val); if (error < 0) return (SET_ERROR(error)); if (val < ASHIFT_MIN || val > zfs_vdev_max_auto_ashift) return (SET_ERROR(-EINVAL)); error = param_set_ulong(buf, kp); if (error < 0) return (SET_ERROR(error)); return (0); } int param_set_max_auto_ashift(const char *buf, zfs_kernel_param_t *kp) { uint64_t val; int error; error = kstrtoull(buf, 0, &val); if (error < 0) return (SET_ERROR(error)); if (val > ASHIFT_MAX || val < zfs_vdev_min_auto_ashift) return (SET_ERROR(-EINVAL)); error = param_set_ulong(buf, kp); if (error < 0) return (SET_ERROR(error)); return (0); } diff --git a/module/os/linux/zfs/zvol_os.c b/module/os/linux/zfs/zvol_os.c index 0caf31307718..0d62b1490702 100644 --- a/module/os/linux/zfs/zvol_os.c +++ b/module/os/linux/zfs/zvol_os.c @@ -1,1098 +1,1102 @@ /* * 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) 2012, 2020 by Delphix. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include unsigned int zvol_major = ZVOL_MAJOR; unsigned int zvol_request_sync = 0; unsigned int zvol_prefetch_bytes = (128 * 1024); unsigned long zvol_max_discard_blocks = 16384; unsigned int zvol_threads = 32; struct zvol_state_os { struct gendisk *zvo_disk; /* generic disk */ struct request_queue *zvo_queue; /* request queue */ dev_t zvo_dev; /* device id */ }; taskq_t *zvol_taskq; static struct ida zvol_ida; typedef struct zv_request { zvol_state_t *zv; struct bio *bio; taskq_ent_t ent; } zv_request_t; /* * Given a path, return TRUE if path is a ZVOL. */ static boolean_t zvol_is_zvol_impl(const char *path) { dev_t dev = 0; if (vdev_lookup_bdev(path, &dev) != 0) return (B_FALSE); if (MAJOR(dev) == zvol_major) return (B_TRUE); return (B_FALSE); } static void zvol_write(void *arg) { zv_request_t *zvr = arg; struct bio *bio = zvr->bio; int error = 0; zfs_uio_t uio; zfs_uio_bvec_init(&uio, bio); zvol_state_t *zv = zvr->zv; ASSERT3P(zv, !=, NULL); ASSERT3U(zv->zv_open_count, >, 0); ASSERT3P(zv->zv_zilog, !=, NULL); /* bio marked as FLUSH need to flush before write */ if (bio_is_flush(bio)) zil_commit(zv->zv_zilog, ZVOL_OBJ); /* Some requests are just for flush and nothing else. */ if (uio.uio_resid == 0) { rw_exit(&zv->zv_suspend_lock); BIO_END_IO(bio, 0); kmem_free(zvr, sizeof (zv_request_t)); return; } struct request_queue *q = zv->zv_zso->zvo_queue; struct gendisk *disk = zv->zv_zso->zvo_disk; ssize_t start_resid = uio.uio_resid; unsigned long start_time; boolean_t acct = blk_queue_io_stat(q); if (acct) start_time = blk_generic_start_io_acct(q, disk, WRITE, bio); boolean_t sync = bio_is_fua(bio) || zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS; zfs_locked_range_t *lr = zfs_rangelock_enter(&zv->zv_rangelock, uio.uio_loffset, uio.uio_resid, RL_WRITER); uint64_t volsize = zv->zv_volsize; while (uio.uio_resid > 0 && uio.uio_loffset < volsize) { uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1); uint64_t off = uio.uio_loffset; dmu_tx_t *tx = dmu_tx_create(zv->zv_objset); if (bytes > volsize - off) /* don't write past the end */ bytes = volsize - off; dmu_tx_hold_write_by_dnode(tx, zv->zv_dn, off, bytes); /* This will only fail for ENOSPC */ error = dmu_tx_assign(tx, TXG_WAIT); if (error) { dmu_tx_abort(tx); break; } error = dmu_write_uio_dnode(zv->zv_dn, &uio, bytes, tx); if (error == 0) { zvol_log_write(zv, tx, off, bytes, sync); } dmu_tx_commit(tx); if (error) break; } zfs_rangelock_exit(lr); int64_t nwritten = start_resid - uio.uio_resid; dataset_kstats_update_write_kstats(&zv->zv_kstat, nwritten); task_io_account_write(nwritten); if (sync) zil_commit(zv->zv_zilog, ZVOL_OBJ); rw_exit(&zv->zv_suspend_lock); if (acct) blk_generic_end_io_acct(q, disk, WRITE, bio, start_time); BIO_END_IO(bio, -error); kmem_free(zvr, sizeof (zv_request_t)); } static void zvol_discard(void *arg) { zv_request_t *zvr = arg; struct bio *bio = zvr->bio; zvol_state_t *zv = zvr->zv; uint64_t start = BIO_BI_SECTOR(bio) << 9; uint64_t size = BIO_BI_SIZE(bio); uint64_t end = start + size; boolean_t sync; int error = 0; dmu_tx_t *tx; ASSERT3P(zv, !=, NULL); ASSERT3U(zv->zv_open_count, >, 0); ASSERT3P(zv->zv_zilog, !=, NULL); struct request_queue *q = zv->zv_zso->zvo_queue; struct gendisk *disk = zv->zv_zso->zvo_disk; unsigned long start_time; boolean_t acct = blk_queue_io_stat(q); if (acct) start_time = blk_generic_start_io_acct(q, disk, WRITE, bio); sync = bio_is_fua(bio) || zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS; if (end > zv->zv_volsize) { error = SET_ERROR(EIO); goto unlock; } /* * Align the request to volume block boundaries when a secure erase is * not required. This will prevent dnode_free_range() from zeroing out * the unaligned parts which is slow (read-modify-write) and useless * since we are not freeing any space by doing so. */ if (!bio_is_secure_erase(bio)) { start = P2ROUNDUP(start, zv->zv_volblocksize); end = P2ALIGN(end, zv->zv_volblocksize); size = end - start; } if (start >= end) goto unlock; zfs_locked_range_t *lr = zfs_rangelock_enter(&zv->zv_rangelock, start, size, RL_WRITER); tx = dmu_tx_create(zv->zv_objset); dmu_tx_mark_netfree(tx); error = dmu_tx_assign(tx, TXG_WAIT); if (error != 0) { dmu_tx_abort(tx); } else { zvol_log_truncate(zv, tx, start, size, B_TRUE); dmu_tx_commit(tx); error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, start, size); } zfs_rangelock_exit(lr); if (error == 0 && sync) zil_commit(zv->zv_zilog, ZVOL_OBJ); unlock: rw_exit(&zv->zv_suspend_lock); if (acct) blk_generic_end_io_acct(q, disk, WRITE, bio, start_time); BIO_END_IO(bio, -error); kmem_free(zvr, sizeof (zv_request_t)); } static void zvol_read(void *arg) { zv_request_t *zvr = arg; struct bio *bio = zvr->bio; int error = 0; zfs_uio_t uio; zfs_uio_bvec_init(&uio, bio); zvol_state_t *zv = zvr->zv; ASSERT3P(zv, !=, NULL); ASSERT3U(zv->zv_open_count, >, 0); struct request_queue *q = zv->zv_zso->zvo_queue; struct gendisk *disk = zv->zv_zso->zvo_disk; ssize_t start_resid = uio.uio_resid; unsigned long start_time; boolean_t acct = blk_queue_io_stat(q); if (acct) start_time = blk_generic_start_io_acct(q, disk, READ, bio); zfs_locked_range_t *lr = zfs_rangelock_enter(&zv->zv_rangelock, uio.uio_loffset, uio.uio_resid, RL_READER); uint64_t volsize = zv->zv_volsize; while (uio.uio_resid > 0 && uio.uio_loffset < volsize) { uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1); /* don't read past the end */ if (bytes > volsize - uio.uio_loffset) bytes = volsize - uio.uio_loffset; error = dmu_read_uio_dnode(zv->zv_dn, &uio, bytes); if (error) { /* convert checksum errors into IO errors */ if (error == ECKSUM) error = SET_ERROR(EIO); break; } } zfs_rangelock_exit(lr); int64_t nread = start_resid - uio.uio_resid; dataset_kstats_update_read_kstats(&zv->zv_kstat, nread); task_io_account_read(nread); rw_exit(&zv->zv_suspend_lock); if (acct) blk_generic_end_io_acct(q, disk, READ, bio, start_time); BIO_END_IO(bio, -error); kmem_free(zvr, sizeof (zv_request_t)); } #ifdef HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS static blk_qc_t zvol_submit_bio(struct bio *bio) #else static MAKE_REQUEST_FN_RET zvol_request(struct request_queue *q, struct bio *bio) #endif { #ifdef HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS +#if defined(HAVE_BIO_BDEV_DISK) + struct request_queue *q = bio->bi_bdev->bd_disk->queue; +#else struct request_queue *q = bio->bi_disk->queue; +#endif #endif zvol_state_t *zv = q->queuedata; fstrans_cookie_t cookie = spl_fstrans_mark(); uint64_t offset = BIO_BI_SECTOR(bio) << 9; uint64_t size = BIO_BI_SIZE(bio); int rw = bio_data_dir(bio); zv_request_t *zvr; if (bio_has_data(bio) && offset + size > zv->zv_volsize) { printk(KERN_INFO "%s: bad access: offset=%llu, size=%lu\n", zv->zv_zso->zvo_disk->disk_name, (long long unsigned)offset, (long unsigned)size); BIO_END_IO(bio, -SET_ERROR(EIO)); goto out; } if (rw == WRITE) { if (unlikely(zv->zv_flags & ZVOL_RDONLY)) { BIO_END_IO(bio, -SET_ERROR(EROFS)); goto out; } /* * Prevents the zvol from being suspended, or the ZIL being * concurrently opened. Will be released after the i/o * completes. */ rw_enter(&zv->zv_suspend_lock, RW_READER); /* * Open a ZIL if this is the first time we have written to this * zvol. We protect zv->zv_zilog with zv_suspend_lock rather * than zv_state_lock so that we don't need to acquire an * additional lock in this path. */ if (zv->zv_zilog == NULL) { rw_exit(&zv->zv_suspend_lock); rw_enter(&zv->zv_suspend_lock, RW_WRITER); if (zv->zv_zilog == NULL) { zv->zv_zilog = zil_open(zv->zv_objset, zvol_get_data); zv->zv_flags |= ZVOL_WRITTEN_TO; } rw_downgrade(&zv->zv_suspend_lock); } zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP); zvr->zv = zv; zvr->bio = bio; taskq_init_ent(&zvr->ent); /* * We don't want this thread to be blocked waiting for i/o to * complete, so we instead wait from a taskq callback. The * i/o may be a ZIL write (via zil_commit()), or a read of an * indirect block, or a read of a data block (if this is a * partial-block write). We will indicate that the i/o is * complete by calling BIO_END_IO() from the taskq callback. * * This design allows the calling thread to continue and * initiate more concurrent operations by calling * zvol_request() again. There are typically only a small * number of threads available to call zvol_request() (e.g. * one per iSCSI target), so keeping the latency of * zvol_request() low is important for performance. * * The zvol_request_sync module parameter allows this * behavior to be altered, for performance evaluation * purposes. If the callback blocks, setting * zvol_request_sync=1 will result in much worse performance. * * We can have up to zvol_threads concurrent i/o's being * processed for all zvols on the system. This is typically * a vast improvement over the zvol_request_sync=1 behavior * of one i/o at a time per zvol. However, an even better * design would be for zvol_request() to initiate the zio * directly, and then be notified by the zio_done callback, * which would call BIO_END_IO(). Unfortunately, the DMU/ZIL * interfaces lack this functionality (they block waiting for * the i/o to complete). */ if (bio_is_discard(bio) || bio_is_secure_erase(bio)) { if (zvol_request_sync) { zvol_discard(zvr); } else { taskq_dispatch_ent(zvol_taskq, zvol_discard, zvr, 0, &zvr->ent); } } else { if (zvol_request_sync) { zvol_write(zvr); } else { taskq_dispatch_ent(zvol_taskq, zvol_write, zvr, 0, &zvr->ent); } } } else { /* * The SCST driver, and possibly others, may issue READ I/Os * with a length of zero bytes. These empty I/Os contain no * data and require no additional handling. */ if (size == 0) { BIO_END_IO(bio, 0); goto out; } zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP); zvr->zv = zv; zvr->bio = bio; taskq_init_ent(&zvr->ent); rw_enter(&zv->zv_suspend_lock, RW_READER); /* See comment in WRITE case above. */ if (zvol_request_sync) { zvol_read(zvr); } else { taskq_dispatch_ent(zvol_taskq, zvol_read, zvr, 0, &zvr->ent); } } out: spl_fstrans_unmark(cookie); #if defined(HAVE_MAKE_REQUEST_FN_RET_QC) || \ defined(HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS) return (BLK_QC_T_NONE); #endif } static int zvol_open(struct block_device *bdev, fmode_t flag) { zvol_state_t *zv; int error = 0; boolean_t drop_suspend = B_TRUE; rw_enter(&zvol_state_lock, RW_READER); /* * Obtain a copy of private_data under the zvol_state_lock to make * sure that either the result of zvol free code path setting * bdev->bd_disk->private_data to NULL is observed, or zvol_free() * is not called on this zv because of the positive zv_open_count. */ zv = bdev->bd_disk->private_data; if (zv == NULL) { rw_exit(&zvol_state_lock); return (SET_ERROR(-ENXIO)); } mutex_enter(&zv->zv_state_lock); /* * make sure zvol is not suspended during first open * (hold zv_suspend_lock) and respect proper lock acquisition * ordering - zv_suspend_lock before zv_state_lock */ if (zv->zv_open_count == 0) { if (!rw_tryenter(&zv->zv_suspend_lock, RW_READER)) { mutex_exit(&zv->zv_state_lock); rw_enter(&zv->zv_suspend_lock, RW_READER); mutex_enter(&zv->zv_state_lock); /* check to see if zv_suspend_lock is needed */ if (zv->zv_open_count != 0) { rw_exit(&zv->zv_suspend_lock); drop_suspend = B_FALSE; } } } else { drop_suspend = B_FALSE; } rw_exit(&zvol_state_lock); ASSERT(MUTEX_HELD(&zv->zv_state_lock)); if (zv->zv_open_count == 0) { ASSERT(RW_READ_HELD(&zv->zv_suspend_lock)); error = -zvol_first_open(zv, !(flag & FMODE_WRITE)); if (error) goto out_mutex; } if ((flag & FMODE_WRITE) && (zv->zv_flags & ZVOL_RDONLY)) { error = -EROFS; goto out_open_count; } zv->zv_open_count++; mutex_exit(&zv->zv_state_lock); if (drop_suspend) rw_exit(&zv->zv_suspend_lock); zfs_check_media_change(bdev); return (0); out_open_count: if (zv->zv_open_count == 0) zvol_last_close(zv); out_mutex: mutex_exit(&zv->zv_state_lock); if (drop_suspend) rw_exit(&zv->zv_suspend_lock); if (error == -EINTR) { error = -ERESTARTSYS; schedule(); } return (SET_ERROR(error)); } static void zvol_release(struct gendisk *disk, fmode_t mode) { zvol_state_t *zv; boolean_t drop_suspend = B_TRUE; rw_enter(&zvol_state_lock, RW_READER); zv = disk->private_data; mutex_enter(&zv->zv_state_lock); ASSERT3U(zv->zv_open_count, >, 0); /* * make sure zvol is not suspended during last close * (hold zv_suspend_lock) and respect proper lock acquisition * ordering - zv_suspend_lock before zv_state_lock */ if (zv->zv_open_count == 1) { if (!rw_tryenter(&zv->zv_suspend_lock, RW_READER)) { mutex_exit(&zv->zv_state_lock); rw_enter(&zv->zv_suspend_lock, RW_READER); mutex_enter(&zv->zv_state_lock); /* check to see if zv_suspend_lock is needed */ if (zv->zv_open_count != 1) { rw_exit(&zv->zv_suspend_lock); drop_suspend = B_FALSE; } } } else { drop_suspend = B_FALSE; } rw_exit(&zvol_state_lock); ASSERT(MUTEX_HELD(&zv->zv_state_lock)); zv->zv_open_count--; if (zv->zv_open_count == 0) { ASSERT(RW_READ_HELD(&zv->zv_suspend_lock)); zvol_last_close(zv); } mutex_exit(&zv->zv_state_lock); if (drop_suspend) rw_exit(&zv->zv_suspend_lock); } static int zvol_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { zvol_state_t *zv = bdev->bd_disk->private_data; int error = 0; ASSERT3U(zv->zv_open_count, >, 0); switch (cmd) { case BLKFLSBUF: fsync_bdev(bdev); invalidate_bdev(bdev); rw_enter(&zv->zv_suspend_lock, RW_READER); if (!(zv->zv_flags & ZVOL_RDONLY)) txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0); rw_exit(&zv->zv_suspend_lock); break; case BLKZNAME: mutex_enter(&zv->zv_state_lock); error = copy_to_user((void *)arg, zv->zv_name, MAXNAMELEN); mutex_exit(&zv->zv_state_lock); break; default: error = -ENOTTY; break; } return (SET_ERROR(error)); } #ifdef CONFIG_COMPAT static int zvol_compat_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { return (zvol_ioctl(bdev, mode, cmd, arg)); } #else #define zvol_compat_ioctl NULL #endif static unsigned int zvol_check_events(struct gendisk *disk, unsigned int clearing) { unsigned int mask = 0; rw_enter(&zvol_state_lock, RW_READER); zvol_state_t *zv = disk->private_data; if (zv != NULL) { mutex_enter(&zv->zv_state_lock); mask = zv->zv_changed ? DISK_EVENT_MEDIA_CHANGE : 0; zv->zv_changed = 0; mutex_exit(&zv->zv_state_lock); } rw_exit(&zvol_state_lock); return (mask); } static int zvol_revalidate_disk(struct gendisk *disk) { rw_enter(&zvol_state_lock, RW_READER); zvol_state_t *zv = disk->private_data; if (zv != NULL) { mutex_enter(&zv->zv_state_lock); set_capacity(zv->zv_zso->zvo_disk, zv->zv_volsize >> SECTOR_BITS); mutex_exit(&zv->zv_state_lock); } rw_exit(&zvol_state_lock); return (0); } static int zvol_update_volsize(zvol_state_t *zv, uint64_t volsize) { struct gendisk *disk = zv->zv_zso->zvo_disk; #if defined(HAVE_REVALIDATE_DISK_SIZE) revalidate_disk_size(disk, zvol_revalidate_disk(disk) == 0); #elif defined(HAVE_REVALIDATE_DISK) revalidate_disk(disk); #else zvol_revalidate_disk(disk); #endif return (0); } static void zvol_clear_private(zvol_state_t *zv) { /* * Cleared while holding zvol_state_lock as a writer * which will prevent zvol_open() from opening it. */ zv->zv_zso->zvo_disk->private_data = NULL; } /* * Provide a simple virtual geometry for legacy compatibility. For devices * smaller than 1 MiB a small head and sector count is used to allow very * tiny devices. For devices over 1 Mib a standard head and sector count * is used to keep the cylinders count reasonable. */ static int zvol_getgeo(struct block_device *bdev, struct hd_geometry *geo) { zvol_state_t *zv = bdev->bd_disk->private_data; sector_t sectors; ASSERT3U(zv->zv_open_count, >, 0); sectors = get_capacity(zv->zv_zso->zvo_disk); if (sectors > 2048) { geo->heads = 16; geo->sectors = 63; } else { geo->heads = 2; geo->sectors = 4; } geo->start = 0; geo->cylinders = sectors / (geo->heads * geo->sectors); return (0); } static struct block_device_operations zvol_ops = { .open = zvol_open, .release = zvol_release, .ioctl = zvol_ioctl, .compat_ioctl = zvol_compat_ioctl, .check_events = zvol_check_events, .revalidate_disk = zvol_revalidate_disk, .getgeo = zvol_getgeo, .owner = THIS_MODULE, #ifdef HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS .submit_bio = zvol_submit_bio, #endif }; /* * Allocate memory for a new zvol_state_t and setup the required * request queue and generic disk structures for the block device. */ static zvol_state_t * zvol_alloc(dev_t dev, const char *name) { zvol_state_t *zv; struct zvol_state_os *zso; uint64_t volmode; if (dsl_prop_get_integer(name, "volmode", &volmode, NULL) != 0) return (NULL); if (volmode == ZFS_VOLMODE_DEFAULT) volmode = zvol_volmode; if (volmode == ZFS_VOLMODE_NONE) return (NULL); zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP); zso = kmem_zalloc(sizeof (struct zvol_state_os), KM_SLEEP); zv->zv_zso = zso; zv->zv_volmode = volmode; list_link_init(&zv->zv_next); mutex_init(&zv->zv_state_lock, NULL, MUTEX_DEFAULT, NULL); #ifdef HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS zso->zvo_queue = blk_alloc_queue(NUMA_NO_NODE); #else zso->zvo_queue = blk_generic_alloc_queue(zvol_request, NUMA_NO_NODE); #endif if (zso->zvo_queue == NULL) goto out_kmem; blk_queue_set_write_cache(zso->zvo_queue, B_TRUE, B_TRUE); /* Limit read-ahead to a single page to prevent over-prefetching. */ blk_queue_set_read_ahead(zso->zvo_queue, 1); /* Disable write merging in favor of the ZIO pipeline. */ blk_queue_flag_set(QUEUE_FLAG_NOMERGES, zso->zvo_queue); zso->zvo_disk = alloc_disk(ZVOL_MINORS); if (zso->zvo_disk == NULL) goto out_queue; zso->zvo_queue->queuedata = zv; zso->zvo_dev = dev; zv->zv_open_count = 0; strlcpy(zv->zv_name, name, MAXNAMELEN); zfs_rangelock_init(&zv->zv_rangelock, NULL, NULL); rw_init(&zv->zv_suspend_lock, NULL, RW_DEFAULT, NULL); zso->zvo_disk->major = zvol_major; zso->zvo_disk->events = DISK_EVENT_MEDIA_CHANGE; if (volmode == ZFS_VOLMODE_DEV) { /* * ZFS_VOLMODE_DEV disable partitioning on ZVOL devices: set * gendisk->minors = 1 as noted in include/linux/genhd.h. * Also disable extended partition numbers (GENHD_FL_EXT_DEVT) * and suppresses partition scanning (GENHD_FL_NO_PART_SCAN) * setting gendisk->flags accordingly. */ zso->zvo_disk->minors = 1; #if defined(GENHD_FL_EXT_DEVT) zso->zvo_disk->flags &= ~GENHD_FL_EXT_DEVT; #endif #if defined(GENHD_FL_NO_PART_SCAN) zso->zvo_disk->flags |= GENHD_FL_NO_PART_SCAN; #endif } zso->zvo_disk->first_minor = (dev & MINORMASK); zso->zvo_disk->fops = &zvol_ops; zso->zvo_disk->private_data = zv; zso->zvo_disk->queue = zso->zvo_queue; snprintf(zso->zvo_disk->disk_name, DISK_NAME_LEN, "%s%d", ZVOL_DEV_NAME, (dev & MINORMASK)); return (zv); out_queue: blk_cleanup_queue(zso->zvo_queue); out_kmem: kmem_free(zso, sizeof (struct zvol_state_os)); kmem_free(zv, sizeof (zvol_state_t)); return (NULL); } /* * Cleanup then free a zvol_state_t which was created by zvol_alloc(). * At this time, the structure is not opened by anyone, is taken off * the zvol_state_list, and has its private data set to NULL. * The zvol_state_lock is dropped. * * This function may take many milliseconds to complete (e.g. we've seen * it take over 256ms), due to the calls to "blk_cleanup_queue" and * "del_gendisk". Thus, consumers need to be careful to account for this * latency when calling this function. */ static void zvol_free(zvol_state_t *zv) { ASSERT(!RW_LOCK_HELD(&zv->zv_suspend_lock)); ASSERT(!MUTEX_HELD(&zv->zv_state_lock)); ASSERT0(zv->zv_open_count); ASSERT3P(zv->zv_zso->zvo_disk->private_data, ==, NULL); rw_destroy(&zv->zv_suspend_lock); zfs_rangelock_fini(&zv->zv_rangelock); del_gendisk(zv->zv_zso->zvo_disk); blk_cleanup_queue(zv->zv_zso->zvo_queue); put_disk(zv->zv_zso->zvo_disk); ida_simple_remove(&zvol_ida, MINOR(zv->zv_zso->zvo_dev) >> ZVOL_MINOR_BITS); mutex_destroy(&zv->zv_state_lock); dataset_kstats_destroy(&zv->zv_kstat); kmem_free(zv->zv_zso, sizeof (struct zvol_state_os)); kmem_free(zv, sizeof (zvol_state_t)); } void zvol_wait_close(zvol_state_t *zv) { } /* * Create a block device minor node and setup the linkage between it * and the specified volume. Once this function returns the block * device is live and ready for use. */ static int zvol_os_create_minor(const char *name) { zvol_state_t *zv; objset_t *os; dmu_object_info_t *doi; uint64_t volsize; uint64_t len; unsigned minor = 0; int error = 0; int idx; uint64_t hash = zvol_name_hash(name); if (zvol_inhibit_dev) return (0); idx = ida_simple_get(&zvol_ida, 0, 0, kmem_flags_convert(KM_SLEEP)); if (idx < 0) return (SET_ERROR(-idx)); minor = idx << ZVOL_MINOR_BITS; zv = zvol_find_by_name_hash(name, hash, RW_NONE); if (zv) { ASSERT(MUTEX_HELD(&zv->zv_state_lock)); mutex_exit(&zv->zv_state_lock); ida_simple_remove(&zvol_ida, idx); return (SET_ERROR(EEXIST)); } doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP); error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, B_TRUE, FTAG, &os); if (error) goto out_doi; error = dmu_object_info(os, ZVOL_OBJ, doi); if (error) goto out_dmu_objset_disown; error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize); if (error) goto out_dmu_objset_disown; zv = zvol_alloc(MKDEV(zvol_major, minor), name); if (zv == NULL) { error = SET_ERROR(EAGAIN); goto out_dmu_objset_disown; } zv->zv_hash = hash; if (dmu_objset_is_snapshot(os)) zv->zv_flags |= ZVOL_RDONLY; zv->zv_volblocksize = doi->doi_data_block_size; zv->zv_volsize = volsize; zv->zv_objset = os; set_capacity(zv->zv_zso->zvo_disk, zv->zv_volsize >> 9); blk_queue_max_hw_sectors(zv->zv_zso->zvo_queue, (DMU_MAX_ACCESS / 4) >> 9); blk_queue_max_segments(zv->zv_zso->zvo_queue, UINT16_MAX); blk_queue_max_segment_size(zv->zv_zso->zvo_queue, UINT_MAX); blk_queue_physical_block_size(zv->zv_zso->zvo_queue, zv->zv_volblocksize); blk_queue_io_opt(zv->zv_zso->zvo_queue, zv->zv_volblocksize); blk_queue_max_discard_sectors(zv->zv_zso->zvo_queue, (zvol_max_discard_blocks * zv->zv_volblocksize) >> 9); blk_queue_discard_granularity(zv->zv_zso->zvo_queue, zv->zv_volblocksize); blk_queue_flag_set(QUEUE_FLAG_DISCARD, zv->zv_zso->zvo_queue); #ifdef QUEUE_FLAG_NONROT blk_queue_flag_set(QUEUE_FLAG_NONROT, zv->zv_zso->zvo_queue); #endif #ifdef QUEUE_FLAG_ADD_RANDOM blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, zv->zv_zso->zvo_queue); #endif /* This flag was introduced in kernel version 4.12. */ #ifdef QUEUE_FLAG_SCSI_PASSTHROUGH blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, zv->zv_zso->zvo_queue); #endif if (spa_writeable(dmu_objset_spa(os))) { if (zil_replay_disable) zil_destroy(dmu_objset_zil(os), B_FALSE); else zil_replay(os, zv, zvol_replay_vector); } ASSERT3P(zv->zv_kstat.dk_kstats, ==, NULL); dataset_kstats_create(&zv->zv_kstat, zv->zv_objset); /* * When udev detects the addition of the device it will immediately * invoke blkid(8) to determine the type of content on the device. * Prefetching the blocks commonly scanned by blkid(8) will speed * up this process. */ len = MIN(MAX(zvol_prefetch_bytes, 0), SPA_MAXBLOCKSIZE); if (len > 0) { dmu_prefetch(os, ZVOL_OBJ, 0, 0, len, ZIO_PRIORITY_SYNC_READ); dmu_prefetch(os, ZVOL_OBJ, 0, volsize - len, len, ZIO_PRIORITY_SYNC_READ); } zv->zv_objset = NULL; out_dmu_objset_disown: dmu_objset_disown(os, B_TRUE, FTAG); out_doi: kmem_free(doi, sizeof (dmu_object_info_t)); /* * Keep in mind that once add_disk() is called, the zvol is * announced to the world, and zvol_open()/zvol_release() can * be called at any time. Incidentally, add_disk() itself calls * zvol_open()->zvol_first_open() and zvol_release()->zvol_last_close() * directly as well. */ if (error == 0) { rw_enter(&zvol_state_lock, RW_WRITER); zvol_insert(zv); rw_exit(&zvol_state_lock); add_disk(zv->zv_zso->zvo_disk); } else { ida_simple_remove(&zvol_ida, idx); } return (error); } static void zvol_rename_minor(zvol_state_t *zv, const char *newname) { int readonly = get_disk_ro(zv->zv_zso->zvo_disk); ASSERT(RW_LOCK_HELD(&zvol_state_lock)); ASSERT(MUTEX_HELD(&zv->zv_state_lock)); strlcpy(zv->zv_name, newname, sizeof (zv->zv_name)); /* move to new hashtable entry */ zv->zv_hash = zvol_name_hash(zv->zv_name); hlist_del(&zv->zv_hlink); hlist_add_head(&zv->zv_hlink, ZVOL_HT_HEAD(zv->zv_hash)); /* * The block device's read-only state is briefly changed causing * a KOBJ_CHANGE uevent to be issued. This ensures udev detects * the name change and fixes the symlinks. This does not change * ZVOL_RDONLY in zv->zv_flags so the actual read-only state never * changes. This would normally be done using kobject_uevent() but * that is a GPL-only symbol which is why we need this workaround. */ set_disk_ro(zv->zv_zso->zvo_disk, !readonly); set_disk_ro(zv->zv_zso->zvo_disk, readonly); } static void zvol_set_disk_ro_impl(zvol_state_t *zv, int flags) { set_disk_ro(zv->zv_zso->zvo_disk, flags); } static void zvol_set_capacity_impl(zvol_state_t *zv, uint64_t capacity) { set_capacity(zv->zv_zso->zvo_disk, capacity); } const static zvol_platform_ops_t zvol_linux_ops = { .zv_free = zvol_free, .zv_rename_minor = zvol_rename_minor, .zv_create_minor = zvol_os_create_minor, .zv_update_volsize = zvol_update_volsize, .zv_clear_private = zvol_clear_private, .zv_is_zvol = zvol_is_zvol_impl, .zv_set_disk_ro = zvol_set_disk_ro_impl, .zv_set_capacity = zvol_set_capacity_impl, }; int zvol_init(void) { int error; int threads = MIN(MAX(zvol_threads, 1), 1024); error = register_blkdev(zvol_major, ZVOL_DRIVER); if (error) { printk(KERN_INFO "ZFS: register_blkdev() failed %d\n", error); return (error); } zvol_taskq = taskq_create(ZVOL_DRIVER, threads, maxclsyspri, threads * 2, INT_MAX, TASKQ_PREPOPULATE | TASKQ_DYNAMIC); if (zvol_taskq == NULL) { unregister_blkdev(zvol_major, ZVOL_DRIVER); return (-ENOMEM); } zvol_init_impl(); ida_init(&zvol_ida); zvol_register_ops(&zvol_linux_ops); return (0); } void zvol_fini(void) { zvol_fini_impl(); unregister_blkdev(zvol_major, ZVOL_DRIVER); taskq_destroy(zvol_taskq); ida_destroy(&zvol_ida); } /* BEGIN CSTYLED */ module_param(zvol_inhibit_dev, uint, 0644); MODULE_PARM_DESC(zvol_inhibit_dev, "Do not create zvol device nodes"); module_param(zvol_major, uint, 0444); MODULE_PARM_DESC(zvol_major, "Major number for zvol device"); module_param(zvol_threads, uint, 0444); MODULE_PARM_DESC(zvol_threads, "Max number of threads to handle I/O requests"); module_param(zvol_request_sync, uint, 0644); MODULE_PARM_DESC(zvol_request_sync, "Synchronously handle bio requests"); module_param(zvol_max_discard_blocks, ulong, 0444); MODULE_PARM_DESC(zvol_max_discard_blocks, "Max number of blocks to discard"); module_param(zvol_prefetch_bytes, uint, 0644); MODULE_PARM_DESC(zvol_prefetch_bytes, "Prefetch N bytes at zvol start+end"); module_param(zvol_volmode, uint, 0644); MODULE_PARM_DESC(zvol_volmode, "Default volmode property value"); /* END CSTYLED */