NVMe: Mismatched host/device page size support
Adds support for devices with max page size smaller than the host's.
In the case we encounter such a host/device combination, the driver will
split a page into as many PRP entries as necessary for the device's page
size capabilities. If the device's reported minimum page size is greater
than the host's, the driver will not attempt to enable the device and
return an error instead.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 974efd0..ed09074 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -38,6 +38,7 @@
#define NVME_CAP_TIMEOUT(cap) (((cap) >> 24) & 0xff)
#define NVME_CAP_STRIDE(cap) (((cap) >> 32) & 0xf)
#define NVME_CAP_MPSMIN(cap) (((cap) >> 48) & 0xf)
+#define NVME_CAP_MPSMAX(cap) (((cap) >> 52) & 0xf)
enum {
NVME_CC_ENABLE = 1 << 0,
@@ -97,6 +98,7 @@
char firmware_rev[8];
u32 max_hw_sectors;
u32 stripe_size;
+ u32 page_size;
u16 oncs;
u16 abort_limit;
u8 event_limit;