@@ -927,6 +927,36 @@ static inline blk_status_t nvme_setup_write_zeroes(struct nvme_ns *ns,
return BLK_STS_OK;
}
+/*
+ * NVMe does not support a dedicated command to issue an atomic write. A write
+ * which does adhere to the device atomic limits will silently be executed
+ * non-atomically. The request issuer should ensure that the write is within
+ * the queue atomic writes limits, but just validate this in case it is not.
+ */
+static bool nvme_valid_atomic_write(struct request *req)
+{
+ struct request_queue *q = req->q;
+ u32 boundary_bytes = queue_atomic_write_boundary_bytes(q);
+
+ if (blk_rq_bytes(req) > queue_atomic_write_unit_max_bytes(q))
+ return false;
+
+ if (boundary_bytes) {
+ u64 mask = boundary_bytes - 1, imask = ~mask;
+ u64 start = blk_rq_pos(req) << SECTOR_SHIFT;
+ u64 end = start + blk_rq_bytes(req) - 1;
+
+ /* If greater then must be crossing a boundary */
+ if (blk_rq_bytes(req) > boundary_bytes)
+ return false;
+
+ if ((start & imask) != (end & imask))
+ return false;
+ }
+
+ return true;
+}
+
static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
struct request *req, struct nvme_command *cmnd,
enum nvme_opcode op)
@@ -942,6 +972,9 @@ static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
if (req->cmd_flags & REQ_RAHEAD)
dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
+ if (req->cmd_flags & REQ_ATOMIC && !nvme_valid_atomic_write(req))
+ return BLK_STS_INVAL;
+
cmnd->rw.opcode = op;
cmnd->rw.flags = 0;
cmnd->rw.nsid = cpu_to_le32(ns->head->ns_id);
@@ -1920,6 +1953,23 @@ static void nvme_configure_metadata(struct nvme_ctrl *ctrl,
}
}
+
+static void nvme_update_atomic_write_disk_info(struct nvme_ns *ns,
+ struct nvme_id_ns *id, struct queue_limits *lim,
+ u32 bs, u32 atomic_bs)
+{
+ unsigned int boundary = 0;
+
+ if (id->nsfeat & NVME_NS_FEAT_ATOMICS && id->nawupf) {
+ if (le16_to_cpu(id->nabspf))
+ boundary = (le16_to_cpu(id->nabspf) + 1) * bs;
+ }
+ lim->atomic_write_hw_max = atomic_bs;
+ lim->atomic_write_hw_boundary = boundary;
+ lim->atomic_write_hw_unit_min = bs;
+ lim->atomic_write_hw_unit_max = rounddown_pow_of_two(atomic_bs);
+}
+
static u32 nvme_max_drv_segments(struct nvme_ctrl *ctrl)
{
return ctrl->max_hw_sectors / (NVME_CTRL_PAGE_SIZE >> SECTOR_SHIFT) + 1;
@@ -1966,6 +2016,8 @@ static bool nvme_update_disk_info(struct nvme_ns *ns, struct nvme_id_ns *id,
atomic_bs = (1 + le16_to_cpu(id->nawupf)) * bs;
else
atomic_bs = (1 + ns->ctrl->subsys->awupf) * bs;
+
+ nvme_update_atomic_write_disk_info(ns, id, lim, bs, atomic_bs);
}
if (id->nsfeat & NVME_NS_FEAT_IO_OPT) {