Commit a14669eb authored by Igor Konopko's avatar Igor Konopko Committed by Jens Axboe
Browse files

lightnvm: Inherit mdts from the parent nvme device 



Current lightnvm and pblk implementation does not care about NVMe max
data transfer size, which can be smaller than 64*K=256K. There are
existing NVMe controllers which NVMe max data transfer size is lower
that 256K (for example 128K, which happens for existing NVMe
controllers which are NVMe spec compliant). Such a controllers are not
able to handle command which contains 64 PPAs, since the the size of
DMAed buffer will be above the capabilities of such a controller.

Signed-off-by: default avatarIgor Konopko <igor.j.konopko@intel.com>
Reviewed-by: default avatarHans Holmberg <hans.holmberg@cnexlabs.com>
Reviewed-by: default avatarJavier González <javier@javigon.com>
Signed-off-by: default avatarMatias Bjørling <mb@lightnvm.io>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent d38954ed

drivers/lightnvm/core.c

+7 −2
Original line number Diff line number Diff line
@@ -325,6 +325,7 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create) 
	struct nvm_target *t;

	struct nvm_tgt_dev *tgt_dev;

	void *targetdata;

	unsigned int mdts;

	int ret;



	switch (create->conf.type) {
@@ -412,8 +413,12 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create) 
	tdisk->private_data = targetdata;

	tqueue->queuedata = targetdata;



	blk_queue_max_hw_sectors(tqueue,

	mdts = (dev->geo.csecs >> 9) * NVM_MAX_VLBA;

	if (dev->geo.mdts) {

		mdts = min_t(u32, dev->geo.mdts,

				(dev->geo.csecs >> 9) * NVM_MAX_VLBA);

	}

	blk_queue_max_hw_sectors(tqueue, mdts);



	set_capacity(tdisk, tt->capacity(targetdata));

	add_disk(tdisk);

drivers/nvme/host/lightnvm.c

+1 −0
Original line number Diff line number Diff line
@@ -977,6 +977,7 @@ int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node) 
	geo->csecs = 1 << ns->lba_shift;

	geo->sos = ns->ms;

	geo->ext = ns->ext;

	geo->mdts = ns->ctrl->max_hw_sectors;



	dev->q = q;

	memcpy(dev->name, disk_name, DISK_NAME_LEN);

include/linux/lightnvm.h

+1 −0
Original line number Diff line number Diff line
@@ -358,6 +358,7 @@ struct nvm_geo { 
	u16	csecs;		/* sector size */

	u16	sos;		/* out-of-band area size */

	bool	ext;		/* metadata in extended data buffer */

	u32	mdts;		/* Max data transfer size*/



	/* device write constrains */

	u32	ws_min;		/* minimum write size */

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