numam-spdk/include/spdk_internal/sgl.h
Ziye Yang ee8f6dd1d5 sgl.h: Add a new internal header file.
The purpose is to reduce the duplicated code in nvmf and iscsi
layer.

Change-Id: I7e96f0d5bb1ba4b81378addca3cdd929056384e9
Signed-off-by: Ziye Yang <ziye.yang@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/8132
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Aleksey Marchuk <alexeymar@mellanox.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: <dongx.yi@intel.com>
2021-06-02 11:34:27 +00:00

128 lines
3.5 KiB
C

/*-
* BSD LICENSE
*
* Copyright (c) Intel Corporation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __SGL_INTERNAL_H__
#define __SGL_INTERNAL_H__
#include "spdk/stdinc.h"
#ifdef __cplusplus
extern "C" {
#endif
struct spdk_iov_sgl {
struct iovec *iov;
int iovcnt;
uint32_t iov_offset;
uint32_t total_size;
};
/**
* Initialize struct spdk_iov_sgl with iov, iovcnt and iov_offset.
*
* \param s the spdk_iov_sgl to be filled.
* \param iov the io vector to fill the s
* \param iovcnt the size the iov
* \param iov_offset the current filled iov_offset for s.
*/
static inline void
spdk_iov_sgl_init(struct spdk_iov_sgl *s, struct iovec *iov, int iovcnt,
uint32_t iov_offset)
{
s->iov = iov;
s->iovcnt = iovcnt;
s->iov_offset = iov_offset;
s->total_size = 0;
}
/**
* Consume the iovs in spdk_iov_sgl with passed bytes
*
* \param s the spdk_iov_sgl which contains the iov
* \param step the bytes_size consumed.
*/
static inline void
spdk_iov_sgl_advance(struct spdk_iov_sgl *s, uint32_t step)
{
s->iov_offset += step;
while (s->iovcnt > 0) {
assert(s->iov != NULL);
if (s->iov_offset < s->iov->iov_len) {
break;
}
s->iov_offset -= s->iov->iov_len;
s->iov++;
s->iovcnt--;
}
}
/**
* Append the data to the struct spdk_iov_sgl pointed by s
*
* \param s the address of the struct spdk_iov_sgl
* \param data the data buffer to be appended
* \param data_len the length of the data.
*
* \return true if all the data is appended.
*/
static inline bool
spdk_iov_sgl_append(struct spdk_iov_sgl *s, uint8_t *data, uint32_t data_len)
{
if (s->iov_offset >= data_len) {
s->iov_offset -= data_len;
} else {
assert(s->iovcnt > 0);
s->iov->iov_base = data + s->iov_offset;
s->iov->iov_len = data_len - s->iov_offset;
s->total_size += data_len - s->iov_offset;
s->iov_offset = 0;
s->iov++;
s->iovcnt--;
if (s->iovcnt == 0) {
return false;
}
}
return true;
}
#ifdef __cplusplus
}
#endif
#endif /* __SGL_INTERNAL_H__ */