diff options
Diffstat (limited to 'drivers/block/nvme.c')
| -rw-r--r-- | drivers/block/nvme.c | 1043 |
1 files changed, 1043 insertions, 0 deletions
diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c new file mode 100644 index 0000000..ef66ecc --- /dev/null +++ b/drivers/block/nvme.c @@ -0,0 +1,1043 @@ +/* + * NVM Express device driver + * Copyright (c) 2011, 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <linux/nvme.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/genhd.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kdev_t.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/pci.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/version.h> + +#define NVME_Q_DEPTH 1024 +#define SQ_SIZE(depth) (depth * sizeof(struct nvme_command)) +#define CQ_SIZE(depth) (depth * sizeof(struct nvme_completion)) +#define NVME_MINORS 64 + +static int nvme_major; +module_param(nvme_major, int, 0); + +/* + * Represents an NVM Express device. Each nvme_dev is a PCI function. + */ +struct nvme_dev { + struct list_head node; + struct nvme_queue **queues; + u32 __iomem *dbs; + struct pci_dev *pci_dev; + int instance; + int queue_count; + u32 ctrl_config; + struct msix_entry *entry; + struct nvme_bar __iomem *bar; + struct list_head namespaces; +}; + +/* + * An NVM Express namespace is equivalent to a SCSI LUN + */ +struct nvme_ns { + struct list_head list; + + struct nvme_dev *dev; + struct request_queue *queue; + struct gendisk *disk; + + int ns_id; + int lba_shift; +}; + +/* + * An NVM Express queue. Each device has at least two (one for admin + * commands and one for I/O commands). + */ +struct nvme_queue { + struct device *q_dmadev; + spinlock_t q_lock; + struct nvme_command *sq_cmds; + volatile struct nvme_completion *cqes; + dma_addr_t sq_dma_addr; + dma_addr_t cq_dma_addr; + wait_queue_head_t sq_full; + struct bio_list sq_cong; + u32 __iomem *q_db; + u16 q_depth; + u16 cq_vector; + u16 sq_head; + u16 sq_tail; + u16 cq_head; + u16 cq_cycle; + unsigned long cmdid_data[]; +}; + +/* + * Check we didin't inadvertently grow the command struct + */ +static inline void _nvme_check_size(void) +{ + BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64); + BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64); + BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64); + BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64); + BUILD_BUG_ON(sizeof(struct nvme_features) != 64); + BUILD_BUG_ON(sizeof(struct nvme_command) != 64); + BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096); + BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096); + BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64); +} + +/** + * alloc_cmdid - Allocate a Command ID + * @param nvmeq The queue that will be used for this command + * @param ctx A pointer that will be passed to the handler + * @param handler The ID of the handler to call + * + * Allocate a Command ID for a queue. The data passed in will + * be passed to the completion handler. This is implemented by using + * the bottom two bits of the ctx pointer to store the handler ID. + * Passing in a pointer that's not 4-byte aligned will cause a BUG. + * We can change this if it becomes a problem. + */ +static int alloc_cmdid(struct nvme_queue *nvmeq, void *ctx, int handler) +{ + int depth = nvmeq->q_depth; + unsigned long data = (unsigned long)ctx | handler; + int cmdid; + + BUG_ON((unsigned long)ctx & 3); + + do { + cmdid = find_first_zero_bit(nvmeq->cmdid_data, depth); + if (cmdid >= depth) + return -EBUSY; + } while (test_and_set_bit(cmdid, nvmeq->cmdid_data)); + + nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(depth)] = data; + return cmdid; +} + +static int alloc_cmdid_killable(struct nvme_queue *nvmeq, void *ctx, + int handler) +{ + int cmdid; + wait_event_killable(nvmeq->sq_full, + (cmdid = alloc_cmdid(nvmeq, ctx, handler)) >= 0); + return (cmdid < 0) ? -EINTR : cmdid; +} + +/* If you need more than four handlers, you'll need to change how + * alloc_cmdid and nvme_process_cq work + */ +enum { + sync_completion_id = 0, + bio_completion_id, +}; + +static unsigned long free_cmdid(struct nvme_queue *nvmeq, int cmdid) +{ + unsigned long data; + + data = nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(nvmeq->q_depth)]; + clear_bit(cmdid, nvmeq->cmdid_data); + wake_up(&nvmeq->sq_full); + return data; +} + +static struct nvme_queue *get_nvmeq(struct nvme_ns *ns) +{ + return ns->dev->queues[1]; +} + +static void put_nvmeq(struct nvme_queue *nvmeq) +{ +} + +/** + * nvme_submit_cmd: Copy a command into a queue and ring the doorbell + * @nvmeq: The queue to use + * @cmd: The command to send + * + * Safe to use from interrupt context + */ +static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd) +{ + unsigned long flags; + u16 tail; + /* XXX: Need to check tail isn't going to overrun head */ + spin_lock_irqsave(&nvmeq->q_lock, flags); + tail = nvmeq->sq_tail; + memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd)); + writel(tail, nvmeq->q_db); + if (++tail == nvmeq->q_depth) + tail = 0; + nvmeq->sq_tail = tail; + spin_unlock_irqrestore(&nvmeq->q_lock, flags); + + return 0; +} + +struct nvme_req_info { + struct bio *bio; + int nents; + struct scatterlist sg[0]; +}; + +/* XXX: use a mempool */ +static struct nvme_req_info *alloc_info(unsigned nseg, gfp_t gfp) +{ + return kmalloc(sizeof(struct nvme_req_info) + + sizeof(struct scatterlist) * nseg, gfp); +} + +static void free_info(struct nvme_req_info *info) +{ + kfree(info); +} + +static void bio_completion(struct nvme_queue *nvmeq, void *ctx, + struct nvme_completion *cqe) +{ + struct nvme_req_info *info = ctx; + struct bio *bio = info->bio; + u16 status = le16_to_cpup(&cqe->status) >> 1; + + dma_unmap_sg(nvmeq->q_dmadev, info->sg, info->nents, + bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + free_info(info); + bio_endio(bio, status ? -EIO : 0); +} + +static int nvme_map_bio(struct device *dev, struct nvme_req_info *info, + struct bio *bio, enum dma_data_direction dma_dir, int psegs) +{ + struct bio_vec *bvec; + struct scatterlist *sg = info->sg; + int i, nsegs; + + sg_init_table(sg, psegs); + bio_for_each_segment(bvec, bio, i) { + sg_set_page(sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset); + /* XXX: handle non-mergable here */ + nsegs++; + } + info->nents = nsegs; + + return dma_map_sg(dev, info->sg, info->nents, dma_dir); +} + +static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns, + struct bio *bio) +{ + struct nvme_rw_command *cmnd; + struct nvme_req_info *info; + enum dma_data_direction dma_dir; + int cmdid; + u16 control; + u32 dsmgmt; + unsigned long flags; + int psegs = bio_phys_segments(ns->queue, bio); + + info = alloc_info(psegs, GFP_NOIO); + if (!info) + goto congestion; + info->bio = bio; + + cmdid = alloc_cmdid(nvmeq, info, bio_completion_id); + if (unlikely(cmdid < 0)) + goto free_info; + + control = 0; + if (bio->bi_rw & REQ_FUA) + control |= NVME_RW_FUA; + if (bio->bi_rw & (REQ_FAILFAST_DEV | REQ_RAHEAD)) + control |= NVME_RW_LR; + + dsmgmt = 0; + if (bio->bi_rw & REQ_RAHEAD) + dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH; + + spin_lock_irqsave(&nvmeq->q_lock, flags); + cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail].rw; + + if (bio_data_dir(bio)) { + cmnd->opcode = nvme_cmd_write; + dma_dir = DMA_TO_DEVICE; + } else { + cmnd->opcode = nvme_cmd_read; + dma_dir = DMA_FROM_DEVICE; + } + + nvme_map_bio(nvmeq->q_dmadev, info, bio, dma_dir, psegs); + + cmnd->flags = 1; + cmnd->command_id = cmdid; + cmnd->nsid = cpu_to_le32(ns->ns_id); + cmnd->prp1 = cpu_to_le64(sg_phys(info->sg)); + /* XXX: Support more than one PRP */ + cmnd->slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9)); + cmnd->length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1); + cmnd->control = cpu_to_le16(control); + cmnd->dsmgmt = cpu_to_le32(dsmgmt); + + writel(nvmeq->sq_tail, nvmeq->q_db); + if (++nvmeq->sq_tail == nvmeq->q_depth) + nvmeq->sq_tail = 0; + + spin_unlock_irqrestore(&nvmeq->q_lock, flags); + + return 0; + + free_info: + free_info(info); + congestion: + return -EBUSY; +} + +/* + * NB: return value of non-zero would mean that we were a stacking driver. + * make_request must always succeed. + */ +static int nvme_make_request(struct request_queue *q, struct bio *bio) +{ + struct nvme_ns *ns = q->queuedata; + struct nvme_queue *nvmeq = get_nvmeq(ns); + + if (nvme_submit_bio_queue(nvmeq, ns, bio)) { + blk_set_queue_congested(q, rw_is_sync(bio->bi_rw)); + bio_list_add(&nvmeq->sq_cong, bio); + } + put_nvmeq(nvmeq); + + return 0; +} + +struct sync_cmd_info { + struct task_struct *task; + u32 result; + int status; +}; + +static void sync_completion(struct nvme_queue *nvmeq, void *ctx, + struct nvme_completion *cqe) +{ + struct sync_cmd_info *cmdinfo = ctx; + cmdinfo->result = le32_to_cpup(&cqe->result); + cmdinfo->status = le16_to_cpup(&cqe->status) >> 1; + wake_up_process(cmdinfo->task); +} + +typedef void (*completion_fn)(struct nvme_queue *, void *, + struct nvme_completion *); + +static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq) +{ + u16 head, cycle; + + static const completion_fn completions[4] = { + [sync_completion_id] = sync_completion, + [bio_completion_id] = bio_completion, + }; + + head = nvmeq->cq_head; + cycle = nvmeq->cq_cycle; + + for (;;) { + unsigned long data; + void *ptr; + unsigned char handler; + struct nvme_completion cqe = nvmeq->cqes[head]; + if ((le16_to_cpu(cqe.status) & 1) != cycle) + break; + nvmeq->sq_head = le16_to_cpu(cqe.sq_head); + if (++head == nvmeq->q_depth) { + head = 0; + cycle = !cycle; + } + + data = free_cmdid(nvmeq, cqe.command_id); + handler = data & 3; + ptr = (void *)(data & ~3UL); + completions[handler](nvmeq, ptr, &cqe); + } + + /* If the controller ignores the cq head doorbell and continuously + * writes to the queue, it is theoretically possible to wrap around + * the queue twice and mistakenly return IRQ_NONE. Linux only + * requires that 0.1% of your interrupts are handled, so this isn't + * a big problem. + */ + if (head == nvmeq->cq_head && cycle == nvmeq->cq_cycle) + return IRQ_NONE; + + writel(head, nvmeq->q_db + 1); + nvmeq->cq_head = head; + nvmeq->cq_cycle = cycle; + + return IRQ_HANDLED; +} + +static irqreturn_t nvme_irq(int irq, void *data) +{ + return nvme_process_cq(data); +} + +/* + * 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 + */ +static int nvme_submit_sync_cmd(struct nvme_queue *q, struct nvme_command *cmd, + u32 *result) +{ + int cmdid; + struct sync_cmd_info cmdinfo; + + cmdinfo.task = current; + cmdinfo.status = -EINTR; + + cmdid = alloc_cmdid_killable(q, &cmdinfo, sync_completion_id); + if (cmdid < 0) + return cmdid; + cmd->common.command_id = cmdid; + + set_current_state(TASK_UNINTERRUPTIBLE); + nvme_submit_cmd(q, cmd); + schedule(); + + if (result) + *result = cmdinfo.result; + + return cmdinfo.status; +} + +static int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd, + u32 *result) +{ + return nvme_submit_sync_cmd(dev->queues[0], cmd, result); +} + +static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id) +{ + int status; + struct nvme_command c; + + memset(&c, 0, sizeof(c)); + c.delete_queue.opcode = opcode; + c.delete_queue.qid = cpu_to_le16(id); + + status = nvme_submit_admin_cmd(dev, &c, NULL); + if (status) + return -EIO; + return 0; +} + +static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid, + struct nvme_queue *nvmeq) +{ + int status; + struct nvme_command c; + int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED; + + memset(&c, 0, sizeof(c)); + c.create_cq.opcode = nvme_admin_create_cq; + c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr); + c.create_cq.cqid = cpu_to_le16(qid); + c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1); + c.create_cq.cq_flags = cpu_to_le16(flags); + c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector); + + status = nvme_submit_admin_cmd(dev, &c, NULL); + if (status) + return -EIO; + return 0; +} + +static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid, + struct nvme_queue *nvmeq) +{ + int status; + struct nvme_command c; + int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM; + + memset(&c, 0, sizeof(c)); + c.create_sq.opcode = nvme_admin_create_sq; + c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr); + c.create_sq.sqid = cpu_to_le16(qid); + c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1); + c.create_sq.sq_flags = cpu_to_le16(flags); + c.create_sq.cqid = cpu_to_le16(qid); + + status = nvme_submit_admin_cmd(dev, &c, NULL); + if (status) + return -EIO; + return 0; +} + +static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid) +{ + return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid); +} + +static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid) +{ + return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid); +} + +static void nvme_free_queue(struct nvme_dev *dev, int qid) +{ + struct nvme_queue *nvmeq = dev->queues[qid]; + + free_irq(dev->entry[nvmeq->cq_vector].vector, nvmeq); + + /* Don't tell the adapter to delete the admin queue */ + if (qid) { + adapter_delete_sq(dev, qid); + adapter_delete_cq(dev, qid); + } + + dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth), + (void *)nvmeq->cqes, nvmeq->cq_dma_addr); + dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth), + nvmeq->sq_cmds, nvmeq->sq_dma_addr); + kfree(nvmeq); +} + +static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid, + int depth, int vector) +{ + struct device *dmadev = &dev->pci_dev->dev; + unsigned extra = (depth + BITS_TO_LONGS(depth)) * sizeof(long); + struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq) + extra, GFP_KERNEL); + if (!nvmeq) + return NULL; + + nvmeq->cqes = dma_alloc_coherent(dmadev, CQ_SIZE(depth), + &nvmeq->cq_dma_addr, GFP_KERNEL); + if (!nvmeq->cqes) + goto free_nvmeq; + memset((void *)nvmeq->cqes, 0, CQ_SIZE(depth)); + + nvmeq->sq_cmds = dma_alloc_coherent(dmadev, SQ_SIZE(depth), + &nvmeq->sq_dma_addr, GFP_KERNEL); + if (!nvmeq->sq_cmds) + goto free_cqdma; + + nvmeq->q_dmadev = dmadev; + spin_lock_init(&nvmeq->q_lock); + nvmeq->cq_head = 0; + nvmeq->cq_cycle = 1; + init_waitqueue_head(&nvmeq->sq_full); + bio_list_init(&nvmeq->sq_cong); + nvmeq->q_db = &dev->dbs[qid * 2]; + nvmeq->q_depth = depth; + nvmeq->cq_vector = vector; + + return nvmeq; + + free_cqdma: + dma_free_coherent(dmadev, CQ_SIZE(nvmeq->q_depth), (void *)nvmeq->cqes, + nvmeq->cq_dma_addr); + free_nvmeq: + kfree(nvmeq); + return NULL; +} + +static __devinit struct nvme_queue *nvme_create_queue(struct nvme_dev *dev, + int qid, int cq_size, int vector) +{ + int result; + struct nvme_queue *nvmeq = nvme_alloc_queue(dev, qid, cq_size, vector); + + result = adapter_alloc_cq(dev, qid, nvmeq); + if (result < 0) + goto free_nvmeq; + + result = adapter_alloc_sq(dev, qid, nvmeq); + if (result < 0) + goto release_cq; + + result = request_irq(dev->entry[vector].vector, nvme_irq, + IRQF_DISABLED | IRQF_SHARED, "nvme", nvmeq); + if (result < 0) + goto release_sq; + + return nvmeq; + + release_sq: + adapter_delete_sq(dev, qid); + release_cq: + adapter_delete_cq(dev, qid); + free_nvmeq: + dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth), + (void *)nvmeq->cqes, nvmeq->cq_dma_addr); + dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth), + nvmeq->sq_cmds, nvmeq->sq_dma_addr); + kfree(nvmeq); + return NULL; +} + +static int __devinit nvme_configure_admin_queue(struct nvme_dev *dev) +{ + int result; + u32 aqa; + struct nvme_queue *nvmeq; + + dev->dbs = ((void __iomem *)dev->bar) + 4096; + + nvmeq = nvme_alloc_queue(dev, 0, 64, 0); + + aqa = nvmeq->q_depth - 1; + aqa |= aqa << 16; + + dev->ctrl_config = NVME_CC_ENABLE | NVME_CC_CSS_NVM; + dev->ctrl_config |= (PAGE_SHIFT - 12) << NVME_CC_MPS_SHIFT; + dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE; + + writel(aqa, &dev->bar->aqa); + writeq(nvmeq->sq_dma_addr, &dev->bar->asq); + writeq(nvmeq->cq_dma_addr, &dev->bar->acq); + writel(dev->ctrl_config, &dev->bar->cc); + + while (!(readl(&dev->bar->csts) & NVME_CSTS_RDY)) { + msleep(100); + if (fatal_signal_pending(current)) + return -EINTR; + } + + result = request_irq(dev->entry[0].vector, nvme_irq, + IRQF_DISABLED | IRQF_SHARED, "nvme admin", nvmeq); + dev->queues[0] = nvmeq; + return result; +} + +static int nvme_identify(struct nvme_ns *ns, void __user *addr, int cns) +{ + struct nvme_dev *dev = ns->dev; + int status; + struct nvme_command c; + void *page; + dma_addr_t dma_addr; + + page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr, + GFP_KERNEL); + + memset(&c, 0, sizeof(c)); + c.identify.opcode = nvme_admin_identify; + c.identify.nsid = cns ? 0 : cpu_to_le32(ns->ns_id); + c.identify.prp1 = cpu_to_le64(dma_addr); + c.identify.cns = cpu_to_le32(cns); + + status = nvme_submit_admin_cmd(dev, &c, NULL); + + if (status) + status = -EIO; + else if (copy_to_user(addr, page, 4096)) + status = -EFAULT; + + dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr); + + return status; +} + +static int nvme_get_range_type(struct nvme_ns *ns, void __user *addr) +{ + struct nvme_dev *dev = ns->dev; + int status; + struct nvme_command c; + void *page; + dma_addr_t dma_addr; + + page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr, + GFP_KERNEL); + + memset(&c, 0, sizeof(c)); + c.features.opcode = nvme_admin_get_features; + c.features.nsid = cpu_to_le32(ns->ns_id); + c.features.prp1 = cpu_to_le64(dma_addr); + c.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE); + + status = nvme_submit_admin_cmd(dev, &c, NULL); + + /* XXX: Assuming first range for now */ + if (status) + status = -EIO; + else if (copy_to_user(addr, page, 64)) + status = -EFAULT; + + dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr); + + 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_IDENTIFY_NS: + return nvme_identify(ns, (void __user *)arg, 0); + case NVME_IOCTL_IDENTIFY_CTRL: + return nvme_identify(ns, (void __user *)arg, 1); + case NVME_IOCTL_GET_RANGE_TYPE: + return nvme_get_range_type(ns, (void __user *)arg); + default: + return -ENOTTY; + } +} + +static const struct block_device_operations nvme_fops = { + .owner = THIS_MODULE, + .ioctl = nvme_ioctl, +}; + +static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int index, + struct nvme_id_ns *id, struct nvme_lba_range_type *rt) +{ + struct nvme_ns *ns; + struct gendisk *disk; + int lbaf; + + if (rt->attributes & NVME_LBART_ATTRIB_HIDE) + return NULL; + + ns = kzalloc(sizeof(*ns), GFP_KERNEL); + if (!ns) + return NULL; + ns->queue = blk_alloc_queue(GFP_KERNEL); + if (!ns->queue) + goto out_free_ns; + ns->queue->queue_flags = QUEUE_FLAG_DEFAULT | QUEUE_FLAG_NOMERGES | + QUEUE_FLAG_NONROT | QUEUE_FLAG_DISCARD; + blk_queue_make_request(ns->queue, nvme_make_request); + ns->dev = dev; + ns->queue->queuedata = ns; + + disk = alloc_disk(NVME_MINORS); + if (!disk) + goto out_free_queue; + ns->ns_id = index; + ns->disk = disk; + lbaf = id->flbas & 0xf; + ns->lba_shift = id->lbaf[lbaf].ds; + + disk->major = nvme_major; + disk->minors = NVME_MINORS; + disk->first_minor = NVME_MINORS * index; + disk->fops = &nvme_fops; + disk->private_data = ns; + disk->queue = ns->queue; + sprintf(disk->disk_name, "nvme%dn%d", dev->instance, index); + set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9)); + + return ns; + + out_free_queue: + blk_cleanup_queue(ns->queue); + out_free_ns: + kfree(ns); + return NULL; +} + +static void nvme_ns_free(struct nvme_ns *ns) +{ + put_disk(ns->disk); + blk_cleanup_queue(ns->queue); + kfree(ns); +} + +static int set_queue_count(struct nvme_dev *dev, int sq_count, int cq_count) +{ + int status; + u32 result; + struct nvme_command c; + u32 q_count = (sq_count - 1) | ((cq_count - 1) << 16); + + memset(&c, 0, sizeof(c)); + c.features.opcode = nvme_admin_get_features; + c.features.fid = cpu_to_le32(NVME_FEAT_NUM_QUEUES); + c.features.dword11 = cpu_to_le32(q_count); + + status = nvme_submit_admin_cmd(dev, &c, &result); + if (status) + return -EIO; + return min(result & 0xffff, result >> 16) + 1; +} + +/* XXX: Create per-CPU queues */ +static int __devinit nvme_setup_io_queues(struct nvme_dev *dev) +{ + int this_cpu; + + set_queue_count(dev, 1, 1); + + this_cpu = get_cpu(); + dev->queues[1] = nvme_create_queue(dev, 1, NVME_Q_DEPTH, this_cpu); + put_cpu(); + if (!dev->queues[1]) + return -ENOMEM; + dev->queue_count++; + + return 0; +} + +static void nvme_free_queues(struct nvme_dev *dev) +{ + int i; + + for (i = dev->queue_count - 1; i >= 0; i--) + nvme_free_queue(dev, i); +} + +static int __devinit nvme_dev_add(struct nvme_dev *dev) +{ + int res, nn, i; + struct nvme_ns *ns, *next; + void *id; + dma_addr_t dma_addr; + struct nvme_command cid, crt; + + res = nvme_setup_io_queues(dev); + if (res) + return res; + + /* XXX: Switch to a SG list once prp2 works */ + id = dma_alloc_coherent(&dev->pci_dev->dev, 8192, &dma_addr, + GFP_KERNEL); + + memset(&cid, 0, sizeof(cid)); + cid.identify.opcode = nvme_admin_identify; + cid.identify.nsid = 0; + cid.identify.prp1 = cpu_to_le64(dma_addr); + cid.identify.cns = cpu_to_le32(1); + + res = nvme_submit_admin_cmd(dev, &cid, NULL); + if (res) { + res = -EIO; + goto out_free; + } + + nn = le32_to_cpup(&((struct nvme_id_ctrl *)id)->nn); + + cid.identify.cns = 0; + memset(&crt, 0, sizeof(crt)); + crt.features.opcode = nvme_admin_get_features; + crt.features.prp1 = cpu_to_le64(dma_addr + 4096); + crt.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE); + + for (i = 0; i < nn; i++) { + cid.identify.nsid = cpu_to_le32(i); + res = nvme_submit_admin_cmd(dev, &cid, NULL); + if (res) + continue; + + if (((struct nvme_id_ns *)id)->ncap == 0) + continue; + + crt.features.nsid = cpu_to_le32(i); + res = nvme_submit_admin_cmd(dev, &crt, NULL); + if (res) + continue; + + ns = nvme_alloc_ns(dev, i, id, id + 4096); + if (ns) + list_add_tail(&ns->list, &dev->namespaces); + } + list_for_each_entry(ns, &dev->namespaces, list) + add_disk(ns->disk); + + dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr); + return 0; + + out_free: + list_for_each_entry_safe(ns, next, &dev->namespaces, list) { + list_del(&ns->list); + nvme_ns_free(ns); + } + + dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr); + return res; +} + +static int nvme_dev_remove(struct nvme_dev *dev) +{ + struct nvme_ns *ns, *next; + + /* TODO: wait all I/O finished or cancel them */ + + list_for_each_entry_safe(ns, next, &dev->namespaces, list) { + list_del(&ns->list); + del_gendisk(ns->disk); + nvme_ns_free(ns); + } + + nvme_free_queues(dev); + + return 0; +} + +/* XXX: Use an ida or something to let remove / add work correctly */ +static void nvme_set_instance(struct nvme_dev *dev) +{ + static int instance; + dev->instance = instance++; +} + +static void nvme_release_instance(struct nvme_dev *dev) +{ +} + +static int __devinit nvme_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + int result = -ENOMEM; + struct nvme_dev *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + dev->entry = kcalloc(num_possible_cpus(), sizeof(*dev->entry), + GFP_KERNEL); + if (!dev->entry) + goto free; + dev->queues = kcalloc(2, sizeof(void *), GFP_KERNEL); + if (!dev->queues) + goto free; + + INIT_LIST_HEAD(&dev->namespaces); + dev->pci_dev = pdev; + pci_set_drvdata(pdev, dev); + dma_set_mask(&dev->pci_dev->dev, DMA_BIT_MASK(64)); + nvme_set_instance(dev); + + dev->bar = ioremap(pci_resource_start(pdev, 0), 8192); + if (!dev->bar) { + result = -ENOMEM; + goto disable; + } + + result = nvme_configure_admin_queue(dev); + if (result) + goto unmap; + dev->queue_count++; + + result = nvme_dev_add(dev); + if (result) + goto delete; + return 0; + + delete: + nvme_free_queues(dev); + unmap: + iounmap(dev->bar); + disable: + pci_disable_msix(pdev); + nvme_release_instance(dev); + free: + kfree(dev->queues); + kfree(dev->entry); + kfree(dev); + return result; +} + +static void __devexit nvme_remove(struct pci_dev *pdev) +{ + struct nvme_dev *dev = pci_get_drvdata(pdev); + nvme_dev_remove(dev); + pci_disable_msix(pdev); + iounmap(dev->bar); + nvme_release_instance(dev); + kfree(dev->queues); + kfree(dev->entry); + kfree(dev); +} + +/* These functions are yet to be implemented */ +#define nvme_error_detected NULL +#define nvme_dump_registers NULL +#define nvme_link_reset NULL +#define nvme_slot_reset NULL +#define nvme_error_resume NULL +#define nvme_suspend NULL +#define nvme_resume NULL + +static struct pci_error_handlers nvme_err_handler = { + .error_detected = nvme_error_detected, + .mmio_enabled = nvme_dump_registers, + .link_reset = nvme_link_reset, + .slot_reset = nvme_slot_reset, + .resume = nvme_error_resume, +}; + +/* Move to pci_ids.h later */ +#define PCI_CLASS_STORAGE_EXPRESS 0x010802 + +static DEFINE_PCI_DEVICE_TABLE(nvme_id_table) = { + { PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) }, + { 0, } +}; +MODULE_DEVICE_TABLE(pci, nvme_id_table); + +static struct pci_driver nvme_driver = { + .name = "nvme", + .id_table = nvme_id_table, + .probe = nvme_probe, + .remove = __devexit_p(nvme_remove), + .suspend = nvme_suspend, + .resume = nvme_resume, + .err_handler = &nvme_err_handler, +}; + +static int __init nvme_init(void) +{ + int result; + + nvme_major = register_blkdev(nvme_major, "nvme"); + if (nvme_major <= 0) + return -EBUSY; + + result = pci_register_driver(&nvme_driver); + if (!result) + return 0; + + unregister_blkdev(nvme_major, "nvme"); + return result; +} + +static void __exit nvme_exit(void) +{ + pci_unregister_driver(&nvme_driver); + unregister_blkdev(nvme_major, "nvme"); +} + +MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("0.1"); +module_init(nvme_init); +module_exit(nvme_exit); |
