Commit ed8df49d authored by Ben Walker's avatar Ben Walker Committed by Jim Harris
Browse files

bdev: Make spdk_bdev_io_set_buf public 



Also make it correctly account for alignment and automatically
use the internal iov element if necessary.

Change-Id: I0b33ef9444f0693c2d6b0cdaf221c4a5b0ad2cc3
Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-on: https://review.gerrithub.io/416870


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
parent 9bb02b9f

include/spdk/bdev_module.h

+14 −0
Original line number Diff line number Diff line
@@ -584,6 +584,20 @@ const struct spdk_bdev_aliases_list *spdk_bdev_get_aliases(const struct spdk_bde 
 */

void spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, uint64_t len);



/**

 * Set the given buffer as the data buffer described by this bdev_io.

 *

 * The portion of the buffer used may be adjusted for memory alignement

 * purposes.

 *

 * \param bdev_io I/O to set the buffer on.

 * \param buf The buffer to set as the active data buffer.

 * \param len The length of the buffer.

 *

 * \return The usable size of the buffer, after adjustments of alignment.

 */

size_t spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf, size_t len);



/**

 * Complete a bdev_io

 *

lib/bdev/bdev.c

+42 −13
Original line number Diff line number Diff line
@@ -377,14 +377,12 @@ spdk_bdev_get_by_name(const char *bdev_name) 
	return NULL;

}



static void

spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf)

size_t

spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf, size_t len)

{

	struct iovec **iovs;

	int *iovcnt;



	assert(bdev_io->internal.get_buf_cb != NULL);

	assert(buf != NULL);

	void *aligned_buf;



	iovs = &bdev_io->u.bdev.iovs;

	iovcnt = &bdev_io->u.bdev.iovcnt;
@@ -394,13 +392,18 @@ spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf) 
		*iovcnt = 1;

	}



	(*iovs)[0].iov_base = (void *)((unsigned long)((char *)buf + 512) & ~511UL);

	(*iovs)[0].iov_len = bdev_io->internal.buf_len;

	if (buf != NULL) {

		aligned_buf = (void *)(((uintptr_t)buf + 512) & ~511UL);

		len = len - ((uintptr_t)aligned_buf - (uintptr_t)buf);

	} else {

		aligned_buf = NULL;

		assert(len == 0);

	}



	(*iovs)[0].iov_base = aligned_buf;

	(*iovs)[0].iov_len = len;



	bdev_io->internal.buf = buf;

	bdev_io->u.bdev.iovs[0].iov_base = (void *)((unsigned long)((char *)buf + 512) & ~511UL);

	bdev_io->u.bdev.iovs[0].iov_len = bdev_io->internal.buf_len;

	bdev_io->internal.get_buf_cb(bdev_io->internal.ch->channel, bdev_io);

	return len;

}



static void
@@ -411,6 +414,7 @@ spdk_bdev_io_put_buf(struct spdk_bdev_io *bdev_io) 
	void *buf;

	bdev_io_stailq_t *stailq;

	struct spdk_bdev_mgmt_channel *ch;

	size_t len;



	assert(bdev_io->u.bdev.iovcnt == 1);
@@ -420,9 +424,11 @@ spdk_bdev_io_put_buf(struct spdk_bdev_io *bdev_io) 
	if (bdev_io->internal.buf_len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {

		pool = g_bdev_mgr.buf_small_pool;

		stailq = &ch->need_buf_small;

		len = SPDK_BDEV_SMALL_BUF_MAX_SIZE + 512;

	} else {

		pool = g_bdev_mgr.buf_large_pool;

		stailq = &ch->need_buf_large;

		len = SPDK_BDEV_LARGE_BUF_MAX_SIZE + 512;

	}



	if (STAILQ_EMPTY(stailq)) {
@@ -430,7 +436,15 @@ spdk_bdev_io_put_buf(struct spdk_bdev_io *bdev_io) 
	} else {

		tmp = STAILQ_FIRST(stailq);

		STAILQ_REMOVE_HEAD(stailq, internal.buf_link);

		spdk_bdev_io_set_buf(tmp, buf);

		len = spdk_bdev_io_set_buf(tmp, buf, len);

		if (len < tmp->internal.buf_len) {

			SPDK_ERRLOG("Unable to use buffer due to alignment\n");

			spdk_mempool_put(pool, buf);

			spdk_bdev_io_set_buf(tmp, NULL, 0);

			return;

		}

		tmp->internal.buf = buf;

		tmp->internal.get_buf_cb(tmp->internal.ch->channel, tmp);

	}

}
@@ -441,6 +455,7 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u 
	bdev_io_stailq_t *stailq;

	void *buf = NULL;

	struct spdk_bdev_mgmt_channel *mgmt_ch;

	size_t buf_len;



	assert(cb != NULL);

	assert(bdev_io->u.bdev.iovs != NULL);
@@ -459,9 +474,11 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u 
	if (len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {

		pool = g_bdev_mgr.buf_small_pool;

		stailq = &mgmt_ch->need_buf_small;

		buf_len = SPDK_BDEV_SMALL_BUF_MAX_SIZE + 512;

	} else {

		pool = g_bdev_mgr.buf_large_pool;

		stailq = &mgmt_ch->need_buf_large;

		buf_len = SPDK_BDEV_LARGE_BUF_MAX_SIZE + 512;

	}



	buf = spdk_mempool_get(pool);
@@ -469,7 +486,19 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u 
	if (!buf) {

		STAILQ_INSERT_TAIL(stailq, bdev_io, internal.buf_link);

	} else {

		spdk_bdev_io_set_buf(bdev_io, buf);

		size_t aligned_len;



		aligned_len = spdk_bdev_io_set_buf(bdev_io, buf, buf_len);

		if (aligned_len < len) {

			SPDK_ERRLOG("Unable to use buffer after alignment calculations.\n");

			spdk_mempool_put(pool, buf);

			spdk_bdev_io_set_buf(bdev_io, NULL, 0);

			STAILQ_INSERT_TAIL(stailq, bdev_io, internal.buf_link);

			return;

		}



		bdev_io->internal.buf = buf;

		bdev_io->internal.get_buf_cb(bdev_io->internal.ch->channel, bdev_io);

	}

}