diff options
Diffstat (limited to 'drivers/nvme/host/core.c')
| -rw-r--r-- | drivers/nvme/host/core.c | 1516 |
1 files changed, 1516 insertions, 0 deletions
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c new file mode 100644 index 000000000..03c46412f --- /dev/null +++ b/drivers/nvme/host/core.c @@ -0,0 +1,1516 @@ +/* + * NVM Express device driver + * Copyright (c) 2011-2014, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/blkdev.h> +#include <linux/blk-mq.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/hdreg.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/list_sort.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/pr.h> +#include <linux/ptrace.h> +#include <linux/nvme_ioctl.h> +#include <linux/t10-pi.h> +#include <scsi/sg.h> +#include <asm/unaligned.h> + +#include "nvme.h" + +#define NVME_MINORS (1U << MINORBITS) + +static int nvme_major; +module_param(nvme_major, int, 0); + +static int nvme_char_major; +module_param(nvme_char_major, int, 0); + +static LIST_HEAD(nvme_ctrl_list); +DEFINE_SPINLOCK(dev_list_lock); + +static struct class *nvme_class; + +static void nvme_free_ns(struct kref *kref) +{ + struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref); + + if (ns->type == NVME_NS_LIGHTNVM) + nvme_nvm_unregister(ns->queue, ns->disk->disk_name); + + spin_lock(&dev_list_lock); + ns->disk->private_data = NULL; + spin_unlock(&dev_list_lock); + + put_disk(ns->disk); + ida_simple_remove(&ns->ctrl->ns_ida, ns->instance); + nvme_put_ctrl(ns->ctrl); + kfree(ns); +} + +static void nvme_put_ns(struct nvme_ns *ns) +{ + kref_put(&ns->kref, nvme_free_ns); +} + +static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk) +{ + struct nvme_ns *ns; + + spin_lock(&dev_list_lock); + ns = disk->private_data; + if (ns && !kref_get_unless_zero(&ns->kref)) + ns = NULL; + spin_unlock(&dev_list_lock); + + return ns; +} + +void nvme_requeue_req(struct request *req) +{ + unsigned long flags; + + blk_mq_requeue_request(req); + spin_lock_irqsave(req->q->queue_lock, flags); + if (!blk_queue_stopped(req->q)) + blk_mq_kick_requeue_list(req->q); + spin_unlock_irqrestore(req->q->queue_lock, flags); +} + +struct request *nvme_alloc_request(struct request_queue *q, + struct nvme_command *cmd, unsigned int flags) +{ + bool write = cmd->common.opcode & 1; + struct request *req; + + req = blk_mq_alloc_request(q, write, flags); + if (IS_ERR(req)) + return req; + + req->cmd_type = REQ_TYPE_DRV_PRIV; + req->cmd_flags |= REQ_FAILFAST_DRIVER; + req->__data_len = 0; + req->__sector = (sector_t) -1; + req->bio = req->biotail = NULL; + + req->cmd = (unsigned char *)cmd; + req->cmd_len = sizeof(struct nvme_command); + req->special = (void *)0; + + return req; +} + +/* + * Returns 0 on success. If the result is negative, it's a Linux error code; + * if the result is positive, it's an NVM Express status code + */ +int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd, + void *buffer, unsigned bufflen, u32 *result, unsigned timeout) +{ + struct request *req; + int ret; + + req = nvme_alloc_request(q, cmd, 0); + if (IS_ERR(req)) + return PTR_ERR(req); + + req->timeout = timeout ? timeout : ADMIN_TIMEOUT; + + if (buffer && bufflen) { + ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL); + if (ret) + goto out; + } + + blk_execute_rq(req->q, NULL, req, 0); + if (result) + *result = (u32)(uintptr_t)req->special; + ret = req->errors; + out: + blk_mq_free_request(req); + return ret; +} + +int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd, + void *buffer, unsigned bufflen) +{ + return __nvme_submit_sync_cmd(q, cmd, buffer, bufflen, NULL, 0); +} + +int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd, + void __user *ubuffer, unsigned bufflen, + void __user *meta_buffer, unsigned meta_len, u32 meta_seed, + u32 *result, unsigned timeout) +{ + bool write = cmd->common.opcode & 1; + struct nvme_ns *ns = q->queuedata; + struct gendisk *disk = ns ? ns->disk : NULL; + struct request *req; + struct bio *bio = NULL; + void *meta = NULL; + int ret; + + req = nvme_alloc_request(q, cmd, 0); + if (IS_ERR(req)) + return PTR_ERR(req); + + req->timeout = timeout ? timeout : ADMIN_TIMEOUT; + + if (ubuffer && bufflen) { + ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen, + GFP_KERNEL); + if (ret) + goto out; + bio = req->bio; + + if (!disk) + goto submit; + bio->bi_bdev = bdget_disk(disk, 0); + if (!bio->bi_bdev) { + ret = -ENODEV; + goto out_unmap; + } + + if (meta_buffer && meta_len) { + struct bio_integrity_payload *bip; + + meta = kmalloc(meta_len, GFP_KERNEL); + if (!meta) { + ret = -ENOMEM; + goto out_unmap; + } + + if (write) { + if (copy_from_user(meta, meta_buffer, + meta_len)) { + ret = -EFAULT; + goto out_free_meta; + } + } + + bip = bio_integrity_alloc(bio, GFP_KERNEL, 1); + if (IS_ERR(bip)) { + ret = PTR_ERR(bip); + goto out_free_meta; + } + + bip->bip_iter.bi_size = meta_len; + bip->bip_iter.bi_sector = meta_seed; + + ret = bio_integrity_add_page(bio, virt_to_page(meta), + meta_len, offset_in_page(meta)); + if (ret != meta_len) { + ret = -ENOMEM; + goto out_free_meta; + } + } + } + submit: + blk_execute_rq(req->q, disk, req, 0); + ret = req->errors; + if (result) + *result = (u32)(uintptr_t)req->special; + if (meta && !ret && !write) { + if (copy_to_user(meta_buffer, meta, meta_len)) + ret = -EFAULT; + } + out_free_meta: + kfree(meta); + out_unmap: + if (bio) { + if (disk && bio->bi_bdev) + bdput(bio->bi_bdev); + blk_rq_unmap_user(bio); + } + out: + blk_mq_free_request(req); + return ret; +} + +int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd, + void __user *ubuffer, unsigned bufflen, u32 *result, + unsigned timeout) +{ + return __nvme_submit_user_cmd(q, cmd, ubuffer, bufflen, NULL, 0, 0, + result, timeout); +} + +int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id) +{ + struct nvme_command c = { }; + int error; + + /* gcc-4.4.4 (at least) has issues with initializers and anon unions */ + c.identify.opcode = nvme_admin_identify; + c.identify.cns = cpu_to_le32(1); + + *id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL); + if (!*id) + return -ENOMEM; + + error = nvme_submit_sync_cmd(dev->admin_q, &c, *id, + sizeof(struct nvme_id_ctrl)); + if (error) + kfree(*id); + return error; +} + +static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list) +{ + struct nvme_command c = { }; + + c.identify.opcode = nvme_admin_identify; + c.identify.cns = cpu_to_le32(2); + c.identify.nsid = cpu_to_le32(nsid); + return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000); +} + +int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid, + struct nvme_id_ns **id) +{ + struct nvme_command c = { }; + int error; + + /* gcc-4.4.4 (at least) has issues with initializers and anon unions */ + c.identify.opcode = nvme_admin_identify, + c.identify.nsid = cpu_to_le32(nsid), + + *id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL); + if (!*id) + return -ENOMEM; + + error = nvme_submit_sync_cmd(dev->admin_q, &c, *id, + sizeof(struct nvme_id_ns)); + if (error) + kfree(*id); + return error; +} + +int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid, + dma_addr_t dma_addr, u32 *result) +{ + struct nvme_command c; + + memset(&c, 0, sizeof(c)); + c.features.opcode = nvme_admin_get_features; + c.features.nsid = cpu_to_le32(nsid); + c.features.prp1 = cpu_to_le64(dma_addr); + c.features.fid = cpu_to_le32(fid); + + return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0); +} + +int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11, + dma_addr_t dma_addr, u32 *result) +{ + struct nvme_command c; + + memset(&c, 0, sizeof(c)); + c.features.opcode = nvme_admin_set_features; + c.features.prp1 = cpu_to_le64(dma_addr); + c.features.fid = cpu_to_le32(fid); + c.features.dword11 = cpu_to_le32(dword11); + + return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0); +} + +int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log) +{ + struct nvme_command c = { }; + int error; + + c.common.opcode = nvme_admin_get_log_page, + c.common.nsid = cpu_to_le32(0xFFFFFFFF), + c.common.cdw10[0] = cpu_to_le32( + (((sizeof(struct nvme_smart_log) / 4) - 1) << 16) | + NVME_LOG_SMART), + + *log = kmalloc(sizeof(struct nvme_smart_log), GFP_KERNEL); + if (!*log) + return -ENOMEM; + + error = nvme_submit_sync_cmd(dev->admin_q, &c, *log, + sizeof(struct nvme_smart_log)); + if (error) + kfree(*log); + return error; +} + +int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count) +{ + u32 q_count = (*count - 1) | ((*count - 1) << 16); + u32 result; + int status, nr_io_queues; + + status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0, + &result); + if (status) + return status; + + nr_io_queues = min(result & 0xffff, result >> 16) + 1; + *count = min(*count, nr_io_queues); + return 0; +} + +static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio) +{ + struct nvme_user_io io; + struct nvme_command c; + unsigned length, meta_len; + void __user *metadata; + + if (copy_from_user(&io, uio, sizeof(io))) + return -EFAULT; + if (io.flags) + return -EINVAL; + + switch (io.opcode) { + case nvme_cmd_write: + case nvme_cmd_read: + case nvme_cmd_compare: + break; + default: + return -EINVAL; + } + + length = (io.nblocks + 1) << ns->lba_shift; + meta_len = (io.nblocks + 1) * ns->ms; + metadata = (void __user *)(uintptr_t)io.metadata; + + if (ns->ext) { + length += meta_len; + meta_len = 0; + } else if (meta_len) { + if ((io.metadata & 3) || !io.metadata) + return -EINVAL; + } + + memset(&c, 0, sizeof(c)); + c.rw.opcode = io.opcode; + c.rw.flags = io.flags; + c.rw.nsid = cpu_to_le32(ns->ns_id); + c.rw.slba = cpu_to_le64(io.slba); + c.rw.length = cpu_to_le16(io.nblocks); + c.rw.control = cpu_to_le16(io.control); + c.rw.dsmgmt = cpu_to_le32(io.dsmgmt); + c.rw.reftag = cpu_to_le32(io.reftag); + c.rw.apptag = cpu_to_le16(io.apptag); + c.rw.appmask = cpu_to_le16(io.appmask); + + return __nvme_submit_user_cmd(ns->queue, &c, + (void __user *)(uintptr_t)io.addr, length, + metadata, meta_len, io.slba, NULL, 0); +} + +static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns, + struct nvme_passthru_cmd __user *ucmd) +{ + struct nvme_passthru_cmd cmd; + struct nvme_command c; + unsigned timeout = 0; + int status; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + if (copy_from_user(&cmd, ucmd, sizeof(cmd))) + return -EFAULT; + if (cmd.flags) + return -EINVAL; + + memset(&c, 0, sizeof(c)); + c.common.opcode = cmd.opcode; + c.common.flags = cmd.flags; + c.common.nsid = cpu_to_le32(cmd.nsid); + c.common.cdw2[0] = cpu_to_le32(cmd.cdw2); + c.common.cdw2[1] = cpu_to_le32(cmd.cdw3); + c.common.cdw10[0] = cpu_to_le32(cmd.cdw10); + c.common.cdw10[1] = cpu_to_le32(cmd.cdw11); + c.common.cdw10[2] = cpu_to_le32(cmd.cdw12); + c.common.cdw10[3] = cpu_to_le32(cmd.cdw13); + c.common.cdw10[4] = cpu_to_le32(cmd.cdw14); + c.common.cdw10[5] = cpu_to_le32(cmd.cdw15); + + if (cmd.timeout_ms) + timeout = msecs_to_jiffies(cmd.timeout_ms); + + status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c, + (void __user *)(uintptr_t)cmd.addr, cmd.data_len, + &cmd.result, timeout); + if (status >= 0) { + if (put_user(cmd.result, &ucmd->result)) + return -EFAULT; + } + + return status; +} + +static int nvme_ioctl(struct block_device *bdev, fmode_t mode, + unsigned int cmd, unsigned long arg) +{ + struct nvme_ns *ns = bdev->bd_disk->private_data; + + switch (cmd) { + case NVME_IOCTL_ID: + force_successful_syscall_return(); + return ns->ns_id; + case NVME_IOCTL_ADMIN_CMD: + return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg); + case NVME_IOCTL_IO_CMD: + return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg); + case NVME_IOCTL_SUBMIT_IO: + return nvme_submit_io(ns, (void __user *)arg); +#ifdef CONFIG_BLK_DEV_NVME_SCSI + case SG_GET_VERSION_NUM: + return nvme_sg_get_version_num((void __user *)arg); + case SG_IO: + return nvme_sg_io(ns, (void __user *)arg); +#endif + default: + return -ENOTTY; + } +} + +#ifdef CONFIG_COMPAT +static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode, + unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case SG_IO: + return -ENOIOCTLCMD; + } + return nvme_ioctl(bdev, mode, cmd, arg); +} +#else +#define nvme_compat_ioctl NULL +#endif + +static int nvme_open(struct block_device *bdev, fmode_t mode) +{ + return nvme_get_ns_from_disk(bdev->bd_disk) ? 0 : -ENXIO; +} + +static void nvme_release(struct gendisk *disk, fmode_t mode) +{ + nvme_put_ns(disk->private_data); +} + +static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo) +{ + /* some standard values */ + geo->heads = 1 << 6; + geo->sectors = 1 << 5; + geo->cylinders = get_capacity(bdev->bd_disk) >> 11; + return 0; +} + +#ifdef CONFIG_BLK_DEV_INTEGRITY +static void nvme_init_integrity(struct nvme_ns *ns) +{ + struct blk_integrity integrity; + + switch (ns->pi_type) { + case NVME_NS_DPS_PI_TYPE3: + integrity.profile = &t10_pi_type3_crc; + break; + case NVME_NS_DPS_PI_TYPE1: + case NVME_NS_DPS_PI_TYPE2: + integrity.profile = &t10_pi_type1_crc; + break; + default: + integrity.profile = NULL; + break; + } + integrity.tuple_size = ns->ms; + blk_integrity_register(ns->disk, &integrity); + blk_queue_max_integrity_segments(ns->queue, 1); +} +#else +static void nvme_init_integrity(struct nvme_ns *ns) +{ +} +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + +static void nvme_config_discard(struct nvme_ns *ns) +{ + u32 logical_block_size = queue_logical_block_size(ns->queue); + ns->queue->limits.discard_zeroes_data = 0; + ns->queue->limits.discard_alignment = logical_block_size; + ns->queue->limits.discard_granularity = logical_block_size; + blk_queue_max_discard_sectors(ns->queue, 0xffffffff); + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue); +} + +static int nvme_revalidate_disk(struct gendisk *disk) +{ + struct nvme_ns *ns = disk->private_data; + struct nvme_id_ns *id; + u8 lbaf, pi_type; + u16 old_ms; + unsigned short bs; + + if (test_bit(NVME_NS_DEAD, &ns->flags)) { + set_capacity(disk, 0); + return -ENODEV; + } + if (nvme_identify_ns(ns->ctrl, ns->ns_id, &id)) { + dev_warn(ns->ctrl->dev, "%s: Identify failure nvme%dn%d\n", + __func__, ns->ctrl->instance, ns->ns_id); + return -ENODEV; + } + if (id->ncap == 0) { + kfree(id); + return -ENODEV; + } + + if (nvme_nvm_ns_supported(ns, id) && ns->type != NVME_NS_LIGHTNVM) { + if (nvme_nvm_register(ns->queue, disk->disk_name)) { + dev_warn(ns->ctrl->dev, + "%s: LightNVM init failure\n", __func__); + kfree(id); + return -ENODEV; + } + ns->type = NVME_NS_LIGHTNVM; + } + + if (ns->ctrl->vs >= NVME_VS(1, 1)) + memcpy(ns->eui, id->eui64, sizeof(ns->eui)); + if (ns->ctrl->vs >= NVME_VS(1, 2)) + memcpy(ns->uuid, id->nguid, sizeof(ns->uuid)); + + old_ms = ns->ms; + lbaf = id->flbas & NVME_NS_FLBAS_LBA_MASK; + ns->lba_shift = id->lbaf[lbaf].ds; + ns->ms = le16_to_cpu(id->lbaf[lbaf].ms); + ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT); + + /* + * If identify namespace failed, use default 512 byte block size so + * block layer can use before failing read/write for 0 capacity. + */ + if (ns->lba_shift == 0) + ns->lba_shift = 9; + bs = 1 << ns->lba_shift; + /* XXX: PI implementation requires metadata equal t10 pi tuple size */ + pi_type = ns->ms == sizeof(struct t10_pi_tuple) ? + id->dps & NVME_NS_DPS_PI_MASK : 0; + + blk_mq_freeze_queue(disk->queue); + if (blk_get_integrity(disk) && (ns->pi_type != pi_type || + ns->ms != old_ms || + bs != queue_logical_block_size(disk->queue) || + (ns->ms && ns->ext))) + blk_integrity_unregister(disk); + + ns->pi_type = pi_type; + blk_queue_logical_block_size(ns->queue, bs); + + if (ns->ms && !blk_get_integrity(disk) && !ns->ext) + nvme_init_integrity(ns); + if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk)) + set_capacity(disk, 0); + else + set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9)); + + if (ns->ctrl->oncs & NVME_CTRL_ONCS_DSM) + nvme_config_discard(ns); + blk_mq_unfreeze_queue(disk->queue); + + kfree(id); + return 0; +} + +static char nvme_pr_type(enum pr_type type) +{ + switch (type) { + case PR_WRITE_EXCLUSIVE: + return 1; + case PR_EXCLUSIVE_ACCESS: + return 2; + case PR_WRITE_EXCLUSIVE_REG_ONLY: + return 3; + case PR_EXCLUSIVE_ACCESS_REG_ONLY: + return 4; + case PR_WRITE_EXCLUSIVE_ALL_REGS: + return 5; + case PR_EXCLUSIVE_ACCESS_ALL_REGS: + return 6; + default: + return 0; + } +}; + +static int nvme_pr_command(struct block_device *bdev, u32 cdw10, + u64 key, u64 sa_key, u8 op) +{ + struct nvme_ns *ns = bdev->bd_disk->private_data; + struct nvme_command c; + u8 data[16] = { 0, }; + + put_unaligned_le64(key, &data[0]); + put_unaligned_le64(sa_key, &data[8]); + + memset(&c, 0, sizeof(c)); + c.common.opcode = op; + c.common.nsid = cpu_to_le32(ns->ns_id); + c.common.cdw10[0] = cpu_to_le32(cdw10); + + return nvme_submit_sync_cmd(ns->queue, &c, data, 16); +} + +static int nvme_pr_register(struct block_device *bdev, u64 old, + u64 new, unsigned flags) +{ + u32 cdw10; + + if (flags & ~PR_FL_IGNORE_KEY) + return -EOPNOTSUPP; + + cdw10 = old ? 2 : 0; + cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0; + cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */ + return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register); +} + +static int nvme_pr_reserve(struct block_device *bdev, u64 key, + enum pr_type type, unsigned flags) +{ + u32 cdw10; + + if (flags & ~PR_FL_IGNORE_KEY) + return -EOPNOTSUPP; + + cdw10 = nvme_pr_type(type) << 8; + cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0); + return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire); +} + +static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new, + enum pr_type type, bool abort) +{ + u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1; + return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire); +} + +static int nvme_pr_clear(struct block_device *bdev, u64 key) +{ + u32 cdw10 = 1 | (key ? 1 << 3 : 0); + return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register); +} + +static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type) +{ + u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0; + return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release); +} + +static const struct pr_ops nvme_pr_ops = { + .pr_register = nvme_pr_register, + .pr_reserve = nvme_pr_reserve, + .pr_release = nvme_pr_release, + .pr_preempt = nvme_pr_preempt, + .pr_clear = nvme_pr_clear, +}; + +static const struct block_device_operations nvme_fops = { + .owner = THIS_MODULE, + .ioctl = nvme_ioctl, + .compat_ioctl = nvme_compat_ioctl, + .open = nvme_open, + .release = nvme_release, + .getgeo = nvme_getgeo, + .revalidate_disk= nvme_revalidate_disk, + .pr_ops = &nvme_pr_ops, +}; + +static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled) +{ + unsigned long timeout = + ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies; + u32 csts, bit = enabled ? NVME_CSTS_RDY : 0; + int ret; + + while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) { + if ((csts & NVME_CSTS_RDY) == bit) + break; + + msleep(100); + if (fatal_signal_pending(current)) + return -EINTR; + if (time_after(jiffies, timeout)) { + dev_err(ctrl->dev, + "Device not ready; aborting %s\n", enabled ? + "initialisation" : "reset"); + return -ENODEV; + } + } + + return ret; +} + +/* + * If the device has been passed off to us in an enabled state, just clear + * the enabled bit. The spec says we should set the 'shutdown notification + * bits', but doing so may cause the device to complete commands to the + * admin queue ... and we don't know what memory that might be pointing at! + */ +int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap) +{ + int ret; + + ctrl->ctrl_config &= ~NVME_CC_SHN_MASK; + ctrl->ctrl_config &= ~NVME_CC_ENABLE; + + ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config); + if (ret) + return ret; + return nvme_wait_ready(ctrl, cap, false); +} + +int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap) +{ + /* + * Default to a 4K page size, with the intention to update this + * path in the future to accomodate architectures with differing + * kernel and IO page sizes. + */ + unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12; + int ret; + + if (page_shift < dev_page_min) { + dev_err(ctrl->dev, + "Minimum device page size %u too large for host (%u)\n", + 1 << dev_page_min, 1 << page_shift); + return -ENODEV; + } + + ctrl->page_size = 1 << page_shift; + + ctrl->ctrl_config = NVME_CC_CSS_NVM; + ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT; + ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE; + ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES; + ctrl->ctrl_config |= NVME_CC_ENABLE; + + ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config); + if (ret) + return ret; + return nvme_wait_ready(ctrl, cap, true); +} + +int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl) +{ + unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies; + u32 csts; + int ret; + + ctrl->ctrl_config &= ~NVME_CC_SHN_MASK; + ctrl->ctrl_config |= NVME_CC_SHN_NORMAL; + + ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config); + if (ret) + return ret; + + while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) { + if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT) + break; + + msleep(100); + if (fatal_signal_pending(current)) + return -EINTR; + if (time_after(jiffies, timeout)) { + dev_err(ctrl->dev, + "Device shutdown incomplete; abort shutdown\n"); + return -ENODEV; + } + } + + return ret; +} + +static void nvme_set_queue_limits(struct nvme_ctrl *ctrl, + struct request_queue *q) +{ + if (ctrl->max_hw_sectors) { + u32 max_segments = + (ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1; + + blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors); + blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX)); + } + if (ctrl->stripe_size) + blk_queue_chunk_sectors(q, ctrl->stripe_size >> 9); + if (ctrl->vwc & NVME_CTRL_VWC_PRESENT) + blk_queue_flush(q, REQ_FLUSH | REQ_FUA); + blk_queue_virt_boundary(q, ctrl->page_size - 1); +} + +/* + * Initialize the cached copies of the Identify data and various controller + * register in our nvme_ctrl structure. This should be called as soon as + * the admin queue is fully up and running. + */ +int nvme_init_identify(struct nvme_ctrl *ctrl) +{ + struct nvme_id_ctrl *id; + u64 cap; + int ret, page_shift; + + ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs); + if (ret) { + dev_err(ctrl->dev, "Reading VS failed (%d)\n", ret); + return ret; + } + + ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap); + if (ret) { + dev_err(ctrl->dev, "Reading CAP failed (%d)\n", ret); + return ret; + } + page_shift = NVME_CAP_MPSMIN(cap) + 12; + + if (ctrl->vs >= NVME_VS(1, 1)) + ctrl->subsystem = NVME_CAP_NSSRC(cap); + + ret = nvme_identify_ctrl(ctrl, &id); + if (ret) { + dev_err(ctrl->dev, "Identify Controller failed (%d)\n", ret); + return -EIO; + } + + ctrl->oncs = le16_to_cpup(&id->oncs); + atomic_set(&ctrl->abort_limit, id->acl + 1); + ctrl->vwc = id->vwc; + memcpy(ctrl->serial, id->sn, sizeof(id->sn)); + memcpy(ctrl->model, id->mn, sizeof(id->mn)); + memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr)); + if (id->mdts) + ctrl->max_hw_sectors = 1 << (id->mdts + page_shift - 9); + else + ctrl->max_hw_sectors = UINT_MAX; + + if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) && id->vs[3]) { + unsigned int max_hw_sectors; + + ctrl->stripe_size = 1 << (id->vs[3] + page_shift); + max_hw_sectors = ctrl->stripe_size >> (page_shift - 9); + if (ctrl->max_hw_sectors) { + ctrl->max_hw_sectors = min(max_hw_sectors, + ctrl->max_hw_sectors); + } else { + ctrl->max_hw_sectors = max_hw_sectors; + } + } + + nvme_set_queue_limits(ctrl, ctrl->admin_q); + + kfree(id); + return 0; +} + +static int nvme_dev_open(struct inode *inode, struct file *file) +{ + struct nvme_ctrl *ctrl; + int instance = iminor(inode); + int ret = -ENODEV; + + spin_lock(&dev_list_lock); + list_for_each_entry(ctrl, &nvme_ctrl_list, node) { + if (ctrl->instance != instance) + continue; + + if (!ctrl->admin_q) { + ret = -EWOULDBLOCK; + break; + } + if (!kref_get_unless_zero(&ctrl->kref)) + break; + file->private_data = ctrl; + ret = 0; + break; + } + spin_unlock(&dev_list_lock); + + return ret; +} + +static int nvme_dev_release(struct inode *inode, struct file *file) +{ + nvme_put_ctrl(file->private_data); + return 0; +} + +static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp) +{ + struct nvme_ns *ns; + int ret; + + mutex_lock(&ctrl->namespaces_mutex); + if (list_empty(&ctrl->namespaces)) { + ret = -ENOTTY; + goto out_unlock; + } + + ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list); + if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) { + dev_warn(ctrl->dev, + "NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n"); + ret = -EINVAL; + goto out_unlock; + } + + dev_warn(ctrl->dev, + "using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n"); + kref_get(&ns->kref); + mutex_unlock(&ctrl->namespaces_mutex); + + ret = nvme_user_cmd(ctrl, ns, argp); + nvme_put_ns(ns); + return ret; + +out_unlock: + mutex_unlock(&ctrl->namespaces_mutex); + return ret; +} + +static long nvme_dev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct nvme_ctrl *ctrl = file->private_data; + void __user *argp = (void __user *)arg; + + switch (cmd) { + case NVME_IOCTL_ADMIN_CMD: + return nvme_user_cmd(ctrl, NULL, argp); + case NVME_IOCTL_IO_CMD: + return nvme_dev_user_cmd(ctrl, argp); + case NVME_IOCTL_RESET: + dev_warn(ctrl->dev, "resetting controller\n"); + return ctrl->ops->reset_ctrl(ctrl); + case NVME_IOCTL_SUBSYS_RESET: + return nvme_reset_subsystem(ctrl); + default: + return -ENOTTY; + } +} + +static const struct file_operations nvme_dev_fops = { + .owner = THIS_MODULE, + .open = nvme_dev_open, + .release = nvme_dev_release, + .unlocked_ioctl = nvme_dev_ioctl, + .compat_ioctl = nvme_dev_ioctl, +}; + +static ssize_t nvme_sysfs_reset(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct nvme_ctrl *ctrl = dev_get_drvdata(dev); + int ret; + + ret = ctrl->ops->reset_ctrl(ctrl); + if (ret < 0) + return ret; + return count; +} +static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset); + +static ssize_t uuid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct nvme_ns *ns = dev_to_disk(dev)->private_data; + return sprintf(buf, "%pU\n", ns->uuid); +} +static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL); + +static ssize_t eui_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct nvme_ns *ns = dev_to_disk(dev)->private_data; + return sprintf(buf, "%8phd\n", ns->eui); +} +static DEVICE_ATTR(eui, S_IRUGO, eui_show, NULL); + +static ssize_t nsid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct nvme_ns *ns = dev_to_disk(dev)->private_data; + return sprintf(buf, "%d\n", ns->ns_id); +} +static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL); + +static struct attribute *nvme_ns_attrs[] = { + &dev_attr_uuid.attr, + &dev_attr_eui.attr, + &dev_attr_nsid.attr, + NULL, +}; + +static umode_t nvme_attrs_are_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct nvme_ns *ns = dev_to_disk(dev)->private_data; + + if (a == &dev_attr_uuid.attr) { + if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid))) + return 0; + } + if (a == &dev_attr_eui.attr) { + if (!memchr_inv(ns->eui, 0, sizeof(ns->eui))) + return 0; + } + return a->mode; +} + +static const struct attribute_group nvme_ns_attr_group = { + .attrs = nvme_ns_attrs, + .is_visible = nvme_attrs_are_visible, +}; + +#define nvme_show_function(field) \ +static ssize_t field##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct nvme_ctrl *ctrl = dev_get_drvdata(dev); \ + return sprintf(buf, "%.*s\n", (int)sizeof(ctrl->field), ctrl->field); \ +} \ +static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL); + +nvme_show_function(model); +nvme_show_function(serial); +nvme_show_function(firmware_rev); + +static struct attribute *nvme_dev_attrs[] = { + &dev_attr_reset_controller.attr, + &dev_attr_model.attr, + &dev_attr_serial.attr, + &dev_attr_firmware_rev.attr, + NULL +}; + +static struct attribute_group nvme_dev_attrs_group = { + .attrs = nvme_dev_attrs, +}; + +static const struct attribute_group *nvme_dev_attr_groups[] = { + &nvme_dev_attrs_group, + NULL, +}; + +static int ns_cmp(void *priv, struct list_head *a, struct list_head *b) +{ + struct nvme_ns *nsa = container_of(a, struct nvme_ns, list); + struct nvme_ns *nsb = container_of(b, struct nvme_ns, list); + + return nsa->ns_id - nsb->ns_id; +} + +static struct nvme_ns *nvme_find_ns(struct nvme_ctrl *ctrl, unsigned nsid) +{ + struct nvme_ns *ns; + + lockdep_assert_held(&ctrl->namespaces_mutex); + + list_for_each_entry(ns, &ctrl->namespaces, list) { + if (ns->ns_id == nsid) + return ns; + if (ns->ns_id > nsid) + break; + } + return NULL; +} + +static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid) +{ + struct nvme_ns *ns; + struct gendisk *disk; + int node = dev_to_node(ctrl->dev); + + lockdep_assert_held(&ctrl->namespaces_mutex); + + ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node); + if (!ns) + return; + + ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL); + if (ns->instance < 0) + goto out_free_ns; + + ns->queue = blk_mq_init_queue(ctrl->tagset); + if (IS_ERR(ns->queue)) + goto out_release_instance; + queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue); + ns->queue->queuedata = ns; + ns->ctrl = ctrl; + + disk = alloc_disk_node(0, node); + if (!disk) + goto out_free_queue; + + kref_init(&ns->kref); + ns->ns_id = nsid; + ns->disk = disk; + ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */ + + + blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift); + nvme_set_queue_limits(ctrl, ns->queue); + + disk->major = nvme_major; + disk->first_minor = 0; + disk->fops = &nvme_fops; + disk->private_data = ns; + disk->queue = ns->queue; + disk->driverfs_dev = ctrl->device; + disk->flags = GENHD_FL_EXT_DEVT; + sprintf(disk->disk_name, "nvme%dn%d", ctrl->instance, ns->instance); + + if (nvme_revalidate_disk(ns->disk)) + goto out_free_disk; + + list_add_tail(&ns->list, &ctrl->namespaces); + kref_get(&ctrl->kref); + if (ns->type == NVME_NS_LIGHTNVM) + return; + + add_disk(ns->disk); + if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj, + &nvme_ns_attr_group)) + pr_warn("%s: failed to create sysfs group for identification\n", + ns->disk->disk_name); + return; + out_free_disk: + kfree(disk); + out_free_queue: + blk_cleanup_queue(ns->queue); + out_release_instance: + ida_simple_remove(&ctrl->ns_ida, ns->instance); + out_free_ns: + kfree(ns); +} + +static void nvme_ns_remove(struct nvme_ns *ns) +{ + if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags)) + return; + + if (ns->disk->flags & GENHD_FL_UP) { + if (blk_get_integrity(ns->disk)) + blk_integrity_unregister(ns->disk); + sysfs_remove_group(&disk_to_dev(ns->disk)->kobj, + &nvme_ns_attr_group); + del_gendisk(ns->disk); + blk_mq_abort_requeue_list(ns->queue); + blk_cleanup_queue(ns->queue); + } + mutex_lock(&ns->ctrl->namespaces_mutex); + list_del_init(&ns->list); + mutex_unlock(&ns->ctrl->namespaces_mutex); + nvme_put_ns(ns); +} + +static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid) +{ + struct nvme_ns *ns; + + ns = nvme_find_ns(ctrl, nsid); + if (ns) { + if (revalidate_disk(ns->disk)) + nvme_ns_remove(ns); + } else + nvme_alloc_ns(ctrl, nsid); +} + +static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn) +{ + struct nvme_ns *ns; + __le32 *ns_list; + unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024); + int ret = 0; + + ns_list = kzalloc(0x1000, GFP_KERNEL); + if (!ns_list) + return -ENOMEM; + + for (i = 0; i < num_lists; i++) { + ret = nvme_identify_ns_list(ctrl, prev, ns_list); + if (ret) + goto out; + + for (j = 0; j < min(nn, 1024U); j++) { + nsid = le32_to_cpu(ns_list[j]); + if (!nsid) + goto out; + + nvme_validate_ns(ctrl, nsid); + + while (++prev < nsid) { + ns = nvme_find_ns(ctrl, prev); + if (ns) + nvme_ns_remove(ns); + } + } + nn -= j; + } + out: + kfree(ns_list); + return ret; +} + +static void __nvme_scan_namespaces(struct nvme_ctrl *ctrl, unsigned nn) +{ + struct nvme_ns *ns, *next; + unsigned i; + + lockdep_assert_held(&ctrl->namespaces_mutex); + + for (i = 1; i <= nn; i++) + nvme_validate_ns(ctrl, i); + + list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) { + if (ns->ns_id > nn) + nvme_ns_remove(ns); + } +} + +void nvme_scan_namespaces(struct nvme_ctrl *ctrl) +{ + struct nvme_id_ctrl *id; + unsigned nn; + + if (nvme_identify_ctrl(ctrl, &id)) + return; + + mutex_lock(&ctrl->namespaces_mutex); + nn = le32_to_cpu(id->nn); + if (ctrl->vs >= NVME_VS(1, 1) && + !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) { + if (!nvme_scan_ns_list(ctrl, nn)) + goto done; + } + __nvme_scan_namespaces(ctrl, le32_to_cpup(&id->nn)); + done: + list_sort(NULL, &ctrl->namespaces, ns_cmp); + mutex_unlock(&ctrl->namespaces_mutex); + kfree(id); +} + +void nvme_remove_namespaces(struct nvme_ctrl *ctrl) +{ + struct nvme_ns *ns, *next; + + list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) + nvme_ns_remove(ns); +} + +static DEFINE_IDA(nvme_instance_ida); + +static int nvme_set_instance(struct nvme_ctrl *ctrl) +{ + int instance, error; + + do { + if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL)) + return -ENODEV; + + spin_lock(&dev_list_lock); + error = ida_get_new(&nvme_instance_ida, &instance); + spin_unlock(&dev_list_lock); + } while (error == -EAGAIN); + + if (error) + return -ENODEV; + + ctrl->instance = instance; + return 0; +} + +static void nvme_release_instance(struct nvme_ctrl *ctrl) +{ + spin_lock(&dev_list_lock); + ida_remove(&nvme_instance_ida, ctrl->instance); + spin_unlock(&dev_list_lock); +} + +void nvme_uninit_ctrl(struct nvme_ctrl *ctrl) + { + device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance)); + + spin_lock(&dev_list_lock); + list_del(&ctrl->node); + spin_unlock(&dev_list_lock); +} + +static void nvme_free_ctrl(struct kref *kref) +{ + struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref); + + put_device(ctrl->device); + nvme_release_instance(ctrl); + ida_destroy(&ctrl->ns_ida); + + ctrl->ops->free_ctrl(ctrl); +} + +void nvme_put_ctrl(struct nvme_ctrl *ctrl) +{ + kref_put(&ctrl->kref, nvme_free_ctrl); +} + +/* + * Initialize a NVMe controller structures. This needs to be called during + * earliest initialization so that we have the initialized structured around + * during probing. + */ +int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev, + const struct nvme_ctrl_ops *ops, unsigned long quirks) +{ + int ret; + + INIT_LIST_HEAD(&ctrl->namespaces); + mutex_init(&ctrl->namespaces_mutex); + kref_init(&ctrl->kref); + ctrl->dev = dev; + ctrl->ops = ops; + ctrl->quirks = quirks; + + ret = nvme_set_instance(ctrl); + if (ret) + goto out; + + ctrl->device = device_create_with_groups(nvme_class, ctrl->dev, + MKDEV(nvme_char_major, ctrl->instance), + dev, nvme_dev_attr_groups, + "nvme%d", ctrl->instance); + if (IS_ERR(ctrl->device)) { + ret = PTR_ERR(ctrl->device); + goto out_release_instance; + } + get_device(ctrl->device); + dev_set_drvdata(ctrl->device, ctrl); + ida_init(&ctrl->ns_ida); + + spin_lock(&dev_list_lock); + list_add_tail(&ctrl->node, &nvme_ctrl_list); + spin_unlock(&dev_list_lock); + + return 0; +out_release_instance: + nvme_release_instance(ctrl); +out: + return ret; +} + +/** + * nvme_kill_queues(): Ends all namespace queues + * @ctrl: the dead controller that needs to end + * + * Call this function when the driver determines it is unable to get the + * controller in a state capable of servicing IO. + */ +void nvme_kill_queues(struct nvme_ctrl *ctrl) +{ + struct nvme_ns *ns; + + mutex_lock(&ctrl->namespaces_mutex); + list_for_each_entry(ns, &ctrl->namespaces, list) { + if (!kref_get_unless_zero(&ns->kref)) + continue; + + /* + * Revalidating a dead namespace sets capacity to 0. This will + * end buffered writers dirtying pages that can't be synced. + */ + if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags)) + revalidate_disk(ns->disk); + + blk_set_queue_dying(ns->queue); + blk_mq_abort_requeue_list(ns->queue); + blk_mq_start_stopped_hw_queues(ns->queue, true); + + nvme_put_ns(ns); + } + mutex_unlock(&ctrl->namespaces_mutex); +} + +void nvme_stop_queues(struct nvme_ctrl *ctrl) +{ + struct nvme_ns *ns; + + mutex_lock(&ctrl->namespaces_mutex); + list_for_each_entry(ns, &ctrl->namespaces, list) { + spin_lock_irq(ns->queue->queue_lock); + queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue); + spin_unlock_irq(ns->queue->queue_lock); + + blk_mq_cancel_requeue_work(ns->queue); + blk_mq_stop_hw_queues(ns->queue); + } + mutex_unlock(&ctrl->namespaces_mutex); +} + +void nvme_start_queues(struct nvme_ctrl *ctrl) +{ + struct nvme_ns *ns; + + mutex_lock(&ctrl->namespaces_mutex); + list_for_each_entry(ns, &ctrl->namespaces, list) { + queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue); + blk_mq_start_stopped_hw_queues(ns->queue, true); + blk_mq_kick_requeue_list(ns->queue); + } + mutex_unlock(&ctrl->namespaces_mutex); +} + +int __init nvme_core_init(void) +{ + int result; + + result = register_blkdev(nvme_major, "nvme"); + if (result < 0) + return result; + else if (result > 0) + nvme_major = result; + + result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme", + &nvme_dev_fops); + if (result < 0) + goto unregister_blkdev; + else if (result > 0) + nvme_char_major = result; + + nvme_class = class_create(THIS_MODULE, "nvme"); + if (IS_ERR(nvme_class)) { + result = PTR_ERR(nvme_class); + goto unregister_chrdev; + } + + return 0; + + unregister_chrdev: + __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme"); + unregister_blkdev: + unregister_blkdev(nvme_major, "nvme"); + return result; +} + +void nvme_core_exit(void) +{ + unregister_blkdev(nvme_major, "nvme"); + class_destroy(nvme_class); + __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme"); +} |