NVMe: Meta data handling through submit io ioctl

This adds support for the extended metadata formats through the submit
IO ioctl, and simplifies the rest when using a separate metadata format.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 49 insertions, 74 deletions

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 973c895bd7af..e919de48ff25 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1745,25 +1745,31 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
         struct nvme_dev *dev = ns->dev;
         struct nvme_user_io io;
         struct nvme_command c;
-        unsigned length, meta_len;
-        int status, i;
-        struct nvme_iod *iod, *meta_iod = NULL;
-        dma_addr_t meta_dma_addr;
-        void *meta, *uninitialized_var(meta_mem);
+        unsigned length, meta_len, prp_len;
+        int status, write;
+        struct nvme_iod *iod;
+        dma_addr_t meta_dma = 0;
+        void *meta = NULL;
 
         if (copy_from_user(&io, uio, sizeof(io)))
                 return -EFAULT;
         length = (io.nblocks + 1) << ns->lba_shift;
         meta_len = (io.nblocks + 1) * ns->ms;
 
-        if (meta_len && ((io.metadata & 3) || !io.metadata))
+        if (meta_len && ((io.metadata & 3) || !io.metadata) && !ns->ext)
                 return -EINVAL;
+        else if (meta_len && ns->ext) {
+                length += meta_len;
+                meta_len = 0;
+        }
+
+        write = io.opcode & 1;
 
         switch (io.opcode) {
         case nvme_cmd_write:
         case nvme_cmd_read:
         case nvme_cmd_compare:
-                iod = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length);
+                iod = nvme_map_user_pages(dev, write, io.addr, length);
                 break;
         default:
                 return -EINVAL;
@@ -1772,6 +1778,27 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
         if (IS_ERR(iod))
                 return PTR_ERR(iod);
 
+        prp_len = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
+        if (length != prp_len) {
+                status = -ENOMEM;
+                goto unmap;
+        }
+        if (meta_len) {
+                meta = dma_alloc_coherent(&dev->pci_dev->dev, meta_len,
+                                                &meta_dma, GFP_KERNEL);
+                if (!meta) {
+                        status = -ENOMEM;
+                        goto unmap;
+                }
+                if (write) {
+                        if (copy_from_user(meta, (void __user *)io.metadata,
+                                                                meta_len)) {
+                                status = -EFAULT;
+                                goto unmap;
+                        }
+                }
+        }
+
         memset(&c, 0, sizeof(c));
         c.rw.opcode = io.opcode;
         c.rw.flags = io.flags;
@@ -1783,75 +1810,21 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
         c.rw.reftag = cpu_to_le32(io.reftag);
         c.rw.apptag = cpu_to_le16(io.apptag);
         c.rw.appmask = cpu_to_le16(io.appmask);
-
-        if (meta_len) {
-                meta_iod = nvme_map_user_pages(dev, io.opcode & 1, io.metadata,
-                                                                meta_len);
-                if (IS_ERR(meta_iod)) {
-                        status = PTR_ERR(meta_iod);
-                        meta_iod = NULL;
-                        goto unmap;
-                }
-
-                meta_mem = dma_alloc_coherent(&dev->pci_dev->dev, meta_len,
-                                                &meta_dma_addr, GFP_KERNEL);
-                if (!meta_mem) {
-                        status = -ENOMEM;
-                        goto unmap;
-                }
-
-                if (io.opcode & 1) {
-                        int meta_offset = 0;
-
-                        for (i = 0; i < meta_iod->nents; i++) {
-                                meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
-                                                meta_iod->sg[i].offset;
-                                memcpy(meta_mem + meta_offset, meta,
-                                                meta_iod->sg[i].length);
-                                kunmap_atomic(meta);
-                                meta_offset += meta_iod->sg[i].length;
-                        }
-                }
-
-                c.rw.metadata = cpu_to_le64(meta_dma_addr);
-        }
-
-        length = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
         c.rw.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
         c.rw.prp2 = cpu_to_le64(iod->first_dma);
-
-        if (length != (io.nblocks + 1) << ns->lba_shift)
-                status = -ENOMEM;
-        else
-                status = nvme_submit_io_cmd(dev, ns, &c, NULL);
-
-        if (meta_len) {
-                if (status == NVME_SC_SUCCESS && !(io.opcode & 1)) {
-                        int meta_offset = 0;
-
-                        for (i = 0; i < meta_iod->nents; i++) {
-                                meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
-                                                meta_iod->sg[i].offset;
-                                memcpy(meta, meta_mem + meta_offset,
-                                                meta_iod->sg[i].length);
-                                kunmap_atomic(meta);
-                                meta_offset += meta_iod->sg[i].length;
-                        }
-                }
-
-                dma_free_coherent(&dev->pci_dev->dev, meta_len, meta_mem,
-                                                                meta_dma_addr);
-        }
-
+        c.rw.metadata = cpu_to_le64(meta_dma);
+        status = nvme_submit_io_cmd(dev, ns, &c, NULL);
  unmap:
-        nvme_unmap_user_pages(dev, io.opcode & 1, iod);
+        nvme_unmap_user_pages(dev, write, iod);
         nvme_free_iod(dev, iod);
-
-        if (meta_iod) {
-                nvme_unmap_user_pages(dev, io.opcode & 1, meta_iod);
-                nvme_free_iod(dev, meta_iod);
+        if (meta) {
+                if (status == NVME_SC_SUCCESS && !write) {
+                        if (copy_to_user((void __user *)io.metadata, meta,
+                                                                meta_len))
+                                status = -EFAULT;
+                }
+                dma_free_coherent(&dev->pci_dev->dev, meta_len, meta, meta_dma);
         }
-
         return status;
 }
 
@@ -2014,7 +1987,8 @@ static int nvme_revalidate_disk(struct gendisk *disk)
         struct nvme_dev *dev = ns->dev;
         struct nvme_id_ns *id;
         dma_addr_t dma_addr;
-        int lbaf, pi_type, old_ms;
+        u8 lbaf, pi_type;
+        u16 old_ms;
         unsigned short bs;
 
         id = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
@@ -2035,6 +2009,7 @@ static int nvme_revalidate_disk(struct gendisk *disk)
         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
@@ -2051,14 +2026,14 @@ static int nvme_revalidate_disk(struct gendisk *disk)
         if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
                                 ns->ms != old_ms ||
                                 bs != queue_logical_block_size(disk->queue) ||
-                                (ns->ms && id->flbas & NVME_NS_FLBAS_META_EXT)))
+                                (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) && (disk->flags & GENHD_FL_UP) &&
-                                !(id->flbas & NVME_NS_FLBAS_META_EXT))
+                                                                !ns->ext)
                 nvme_init_integrity(ns);
 
         if (id->ncap == 0 || (ns->ms && !blk_get_integrity(disk)))