return 0;
}
-struct nvme_prps {
- int npages; /* 0 means small pool in use */
+/*
+ * The nvme_iod describes the data in an I/O, including the list of PRP
+ * entries. You can't see it in this data structure because C doesn't let
+ * me express that. Use nvme_alloc_iod to ensure there's enough space
+ * allocated to store the PRP list.
+ */
+struct nvme_iod {
+ void *private; /* For the use of the submitter of the I/O */
+ int npages; /* In the PRP list. 0 means small pool in use */
+ int offset; /* Of PRP list */
+ int nents; /* Used in scatterlist */
+ int length; /* Of data, in bytes */
dma_addr_t first_dma;
- __le64 *list[0];
+ struct scatterlist sg[0];
};
-static void nvme_free_prps(struct nvme_dev *dev, struct nvme_prps *prps)
+static __le64 **iod_list(struct nvme_iod *iod)
{
- const int last_prp = PAGE_SIZE / 8 - 1;
- int i;
- dma_addr_t prp_dma;
+ return ((void *)iod) + iod->offset;
+}
- if (!prps)
- return;
+/*
+ * Will slightly overestimate the number of pages needed. This is OK
+ * as it only leads to a small amount of wasted memory for the lifetime of
+ * the I/O.
+ */
+static int nvme_npages(unsigned size)
+{
+ unsigned nprps = DIV_ROUND_UP(size + PAGE_SIZE, PAGE_SIZE);
+ return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
+}
- prp_dma = prps->first_dma;
+static struct nvme_iod *
+nvme_alloc_iod(unsigned nseg, unsigned nbytes, gfp_t gfp)
+{
+ struct nvme_iod *iod = kmalloc(sizeof(struct nvme_iod) +
+ sizeof(__le64 *) * nvme_npages(nbytes) +
+ sizeof(struct scatterlist) * nseg, gfp);
- if (prps->npages == 0)
- dma_pool_free(dev->prp_small_pool, prps->list[0], prp_dma);
- for (i = 0; i < prps->npages; i++) {
- __le64 *prp_list = prps->list[i];
- dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
- dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
- prp_dma = next_prp_dma;
+ if (iod) {
+ iod->offset = offsetof(struct nvme_iod, sg[nseg]);
+ iod->npages = -1;
+ iod->length = nbytes;
}
- kfree(prps);
-}
-struct nvme_bio {
- struct bio *bio;
- int nents;
- struct nvme_prps *prps;
- struct scatterlist sg[0];
-};
-
-/* XXX: use a mempool */
-static struct nvme_bio *alloc_nbio(unsigned nseg, gfp_t gfp)
-{
- return kzalloc(sizeof(struct nvme_bio) +
- sizeof(struct scatterlist) * nseg, gfp);
+ return iod;
}
-static void free_nbio(struct nvme_dev *dev, struct nvme_bio *nbio)
+static void nvme_free_iod(struct nvme_dev *dev, struct nvme_iod *iod)
{
- nvme_free_prps(dev, nbio->prps);
- kfree(nbio);
+ const int last_prp = PAGE_SIZE / 8 - 1;
+ int i;
+ __le64 **list = iod_list(iod);
+ dma_addr_t prp_dma = iod->first_dma;
+
+ if (iod->npages == 0)
+ dma_pool_free(dev->prp_small_pool, list[0], prp_dma);
+ for (i = 0; i < iod->npages; i++) {
+ __le64 *prp_list = list[i];
+ dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
+ dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
+ prp_dma = next_prp_dma;
+ }
+ kfree(iod);
}
static void requeue_bio(struct nvme_dev *dev, struct bio *bio)
static void bio_completion(struct nvme_dev *dev, void *ctx,
struct nvme_completion *cqe)
{
- struct nvme_bio *nbio = ctx;
- struct bio *bio = nbio->bio;
+ struct nvme_iod *iod = ctx;
+ struct bio *bio = iod->private;
u16 status = le16_to_cpup(&cqe->status) >> 1;
- dma_unmap_sg(&dev->pci_dev->dev, nbio->sg, nbio->nents,
+ dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents,
bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
- free_nbio(dev, nbio);
+ nvme_free_iod(dev, iod);
if (status) {
bio_endio(bio, -EIO);
} else if (bio->bi_vcnt > bio->bi_idx) {
}
/* length is in bytes. gfp flags indicates whether we may sleep. */
-static struct nvme_prps *nvme_setup_prps(struct nvme_dev *dev,
- struct nvme_common_command *cmd,
- struct scatterlist *sg, int *len,
- gfp_t gfp)
+static int nvme_setup_prps(struct nvme_dev *dev,
+ struct nvme_common_command *cmd, struct nvme_iod *iod,
+ int total_len, gfp_t gfp)
{
struct dma_pool *pool;
- int length = *len;
+ int length = total_len;
+ struct scatterlist *sg = iod->sg;
int dma_len = sg_dma_len(sg);
u64 dma_addr = sg_dma_address(sg);
int offset = offset_in_page(dma_addr);
__le64 *prp_list;
+ __le64 **list = iod_list(iod);
dma_addr_t prp_dma;
- int nprps, npages, i;
- struct nvme_prps *prps = NULL;
+ int nprps, i;
cmd->prp1 = cpu_to_le64(dma_addr);
length -= (PAGE_SIZE - offset);
if (length <= 0)
- return prps;
+ return total_len;
dma_len -= (PAGE_SIZE - offset);
if (dma_len) {
if (length <= PAGE_SIZE) {
cmd->prp2 = cpu_to_le64(dma_addr);
- return prps;
+ return total_len;
}
nprps = DIV_ROUND_UP(length, PAGE_SIZE);
- npages = DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
- prps = kmalloc(sizeof(*prps) + sizeof(__le64 *) * npages, gfp);
- if (!prps) {
- cmd->prp2 = cpu_to_le64(dma_addr);
- *len = (*len - length) + PAGE_SIZE;
- return prps;
- }
-
if (nprps <= (256 / 8)) {
pool = dev->prp_small_pool;
- prps->npages = 0;
+ iod->npages = 0;
} else {
pool = dev->prp_page_pool;
- prps->npages = 1;
+ iod->npages = 1;
}
prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
if (!prp_list) {
cmd->prp2 = cpu_to_le64(dma_addr);
- *len = (*len - length) + PAGE_SIZE;
- kfree(prps);
- return NULL;
+ iod->npages = -1;
+ return (total_len - length) + PAGE_SIZE;
}
- prps->list[0] = prp_list;
- prps->first_dma = prp_dma;
+ list[0] = prp_list;
+ iod->first_dma = prp_dma;
cmd->prp2 = cpu_to_le64(prp_dma);
i = 0;
for (;;) {
if (i == PAGE_SIZE / 8) {
__le64 *old_prp_list = prp_list;
prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
- if (!prp_list) {
- *len = (*len - length);
- return prps;
- }
- prps->list[prps->npages++] = prp_list;
+ if (!prp_list)
+ return total_len - length;
+ list[iod->npages++] = prp_list;
prp_list[0] = old_prp_list[i - 1];
old_prp_list[i - 1] = cpu_to_le64(prp_dma);
i = 1;
dma_len = sg_dma_len(sg);
}
- return prps;
+ return total_len;
}
/* NVMe scatterlists require no holes in the virtual address */
#define BIOVEC_NOT_VIRT_MERGEABLE(vec1, vec2) ((vec2)->bv_offset || \
(((vec1)->bv_offset + (vec1)->bv_len) % PAGE_SIZE))
-static int nvme_map_bio(struct device *dev, struct nvme_bio *nbio,
+static int nvme_map_bio(struct device *dev, struct nvme_iod *iod,
struct bio *bio, enum dma_data_direction dma_dir, int psegs)
{
struct bio_vec *bvec, *bvprv = NULL;
struct scatterlist *sg = NULL;
int i, old_idx, length = 0, nsegs = 0;
- sg_init_table(nbio->sg, psegs);
+ sg_init_table(iod->sg, psegs);
old_idx = bio->bi_idx;
bio_for_each_segment(bvec, bio, i) {
if (bvprv && BIOVEC_PHYS_MERGEABLE(bvprv, bvec)) {
} else {
if (bvprv && BIOVEC_NOT_VIRT_MERGEABLE(bvprv, bvec))
break;
- sg = sg ? sg + 1 : nbio->sg;
+ sg = sg ? sg + 1 : iod->sg;
sg_set_page(sg, bvec->bv_page, bvec->bv_len,
bvec->bv_offset);
nsegs++;
bvprv = bvec;
}
bio->bi_idx = i;
- nbio->nents = nsegs;
+ iod->nents = nsegs;
sg_mark_end(sg);
- if (dma_map_sg(dev, nbio->sg, nbio->nents, dma_dir) == 0) {
+ if (dma_map_sg(dev, iod->sg, iod->nents, dma_dir) == 0) {
bio->bi_idx = old_idx;
return -ENOMEM;
}
struct bio *bio)
{
struct nvme_command *cmnd;
- struct nvme_bio *nbio;
+ struct nvme_iod *iod;
enum dma_data_direction dma_dir;
int cmdid, length, result = -ENOMEM;
u16 control;
return result;
}
- nbio = alloc_nbio(psegs, GFP_ATOMIC);
- if (!nbio)
+ iod = nvme_alloc_iod(psegs, bio->bi_size, GFP_ATOMIC);
+ if (!iod)
goto nomem;
- nbio->bio = bio;
+ iod->private = bio;
result = -EBUSY;
- cmdid = alloc_cmdid(nvmeq, nbio, bio_completion, IO_TIMEOUT);
+ cmdid = alloc_cmdid(nvmeq, iod, bio_completion, IO_TIMEOUT);
if (unlikely(cmdid < 0))
- goto free_nbio;
+ goto free_iod;
if ((bio->bi_rw & REQ_FLUSH) && !psegs)
return nvme_submit_flush(nvmeq, ns, cmdid);
dma_dir = DMA_FROM_DEVICE;
}
- result = nvme_map_bio(nvmeq->q_dmadev, nbio, bio, dma_dir, psegs);
+ result = nvme_map_bio(nvmeq->q_dmadev, iod, bio, dma_dir, psegs);
if (result < 0)
- goto free_nbio;
+ goto free_iod;
length = result;
cmnd->rw.command_id = cmdid;
cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
- nbio->prps = nvme_setup_prps(nvmeq->dev, &cmnd->common, nbio->sg,
- &length, GFP_ATOMIC);
+ length = nvme_setup_prps(nvmeq->dev, &cmnd->common, iod, length,
+ GFP_ATOMIC);
cmnd->rw.slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
cmnd->rw.length = cpu_to_le16((length >> ns->lba_shift) - 1);
cmnd->rw.control = cpu_to_le16(control);
return 0;
- free_nbio:
- free_nbio(nvmeq->dev, nbio);
+ free_iod:
+ nvme_free_iod(nvmeq->dev, iod);
nomem:
return result;
}
return result;
}
-static int nvme_map_user_pages(struct nvme_dev *dev, int write,
- unsigned long addr, unsigned length,
- struct scatterlist **sgp)
+static struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
+ unsigned long addr, unsigned length)
{
int i, err, count, nents, offset;
struct scatterlist *sg;
struct page **pages;
+ struct nvme_iod *iod;
if (addr & 3)
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
if (!length)
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
offset = offset_in_page(addr);
count = DIV_ROUND_UP(offset + length, PAGE_SIZE);
goto put_pages;
}
- sg = kcalloc(count, sizeof(*sg), GFP_KERNEL);
+ iod = nvme_alloc_iod(count, length, GFP_KERNEL);
+ sg = iod->sg;
sg_init_table(sg, count);
for (i = 0; i < count; i++) {
sg_set_page(&sg[i], pages[i],
nents = dma_map_sg(&dev->pci_dev->dev, sg, count,
write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
if (!nents)
- goto put_pages;
+ goto free_iod;
kfree(pages);
- *sgp = sg;
- return nents;
+ return iod;
+ free_iod:
+ kfree(iod);
put_pages:
for (i = 0; i < count; i++)
put_page(pages[i]);
kfree(pages);
- return err;
+ return ERR_PTR(err);
}
static void nvme_unmap_user_pages(struct nvme_dev *dev, int write,
- unsigned long addr, int length, struct scatterlist *sg)
+ unsigned long addr, int length, struct nvme_iod *iod)
{
+ struct scatterlist *sg = iod->sg;
int i, count;
count = DIV_ROUND_UP(offset_in_page(addr) + length, PAGE_SIZE);
struct nvme_user_io io;
struct nvme_command c;
unsigned length;
- int nents, status;
- struct scatterlist *sg;
- struct nvme_prps *prps;
+ int status;
+ struct nvme_iod *iod;
if (copy_from_user(&io, uio, sizeof(io)))
return -EFAULT;
case nvme_cmd_write:
case nvme_cmd_read:
case nvme_cmd_compare:
- nents = nvme_map_user_pages(dev, io.opcode & 1, io.addr,
- length, &sg);
+ iod = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length);
break;
default:
return -EINVAL;
}
- if (nents < 0)
- return nents;
+ if (IS_ERR(iod))
+ return PTR_ERR(iod);
memset(&c, 0, sizeof(c));
c.rw.opcode = io.opcode;
c.rw.apptag = io.apptag;
c.rw.appmask = io.appmask;
/* XXX: metadata */
- prps = nvme_setup_prps(dev, &c.common, sg, &length, GFP_KERNEL);
+ length = nvme_setup_prps(dev, &c.common, iod, length, GFP_KERNEL);
nvmeq = get_nvmeq(dev);
/*
else
status = nvme_submit_sync_cmd(nvmeq, &c, NULL, IO_TIMEOUT);
- nvme_unmap_user_pages(dev, io.opcode & 1, io.addr, length, sg);
- nvme_free_prps(dev, prps);
+ nvme_unmap_user_pages(dev, io.opcode & 1, io.addr, length, iod);
+ nvme_free_iod(dev, iod);
return status;
}
struct nvme_dev *dev = ns->dev;
struct nvme_admin_cmd cmd;
struct nvme_command c;
- int status, length, nents = 0;
- struct scatterlist *sg;
- struct nvme_prps *prps = NULL;
+ int status, length;
+ struct nvme_iod *iod;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
length = cmd.data_len;
if (cmd.data_len) {
- nents = nvme_map_user_pages(dev, 1, cmd.addr, length, &sg);
- if (nents < 0)
- return nents;
- prps = nvme_setup_prps(dev, &c.common, sg, &length, GFP_KERNEL);
+ iod = nvme_map_user_pages(dev, 1, cmd.addr, length);
+ if (IS_ERR(iod))
+ return PTR_ERR(iod);
+ length = nvme_setup_prps(dev, &c.common, iod, length,
+ GFP_KERNEL);
}
if (length != cmd.data_len)
status = -ENOMEM;
else
status = nvme_submit_admin_cmd(dev, &c, NULL);
+
if (cmd.data_len) {
- nvme_unmap_user_pages(dev, 0, cmd.addr, cmd.data_len, sg);
- nvme_free_prps(dev, prps);
+ nvme_unmap_user_pages(dev, 0, cmd.addr, cmd.data_len, iod);
+ nvme_free_iod(dev, iod);
}
return status;
}
projects / cascardo / linux.git / commitdiff