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/*
* Copyright (c) 2004, 2005 Christophe Varoqui
*/
#include <string.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <sys/stat.h>
#include "checkers.h"
#include "libsg.h"
#include "../libmultipath/sg_include.h"
int
sg_read (int sg_fd, unsigned char * buff, int buff_len,
unsigned char * sense, int sense_len, unsigned int timeout)
{
/* defaults */
int blocks;
long long start_block = 0;
int bs = 512;
int cdbsz = 10;
int * diop = NULL;
unsigned char rdCmd[cdbsz];
unsigned char *sbb = sense;
struct sg_io_hdr io_hdr;
int res;
int rd_opcode[] = {0x8, 0x28, 0xa8, 0x88};
int sz_ind;
struct stat filestatus;
int retry_count = 3;
if (fstat(sg_fd, &filestatus) != 0)
return PATH_DOWN;
bs = (filestatus.st_blksize > 4096)? 4096: filestatus.st_blksize;
blocks = buff_len / bs;
memset(rdCmd, 0, cdbsz);
sz_ind = 1;
rdCmd[0] = rd_opcode[sz_ind];
rdCmd[2] = (unsigned char)((start_block >> 24) & 0xff);
rdCmd[3] = (unsigned char)((start_block >> 16) & 0xff);
rdCmd[4] = (unsigned char)((start_block >> 8) & 0xff);
rdCmd[5] = (unsigned char)(start_block & 0xff);
rdCmd[7] = (unsigned char)((blocks >> 8) & 0xff);
rdCmd[8] = (unsigned char)(blocks & 0xff);
memset(&io_hdr, 0, sizeof(struct sg_io_hdr));
io_hdr.interface_id = 'S';
io_hdr.cmd_len = cdbsz;
io_hdr.cmdp = rdCmd;
io_hdr.dxfer_direction = SG_DXFER_FROM_DEV;
io_hdr.dxfer_len = bs * blocks;
io_hdr.dxferp = buff;
io_hdr.mx_sb_len = sense_len;
io_hdr.sbp = sense;
io_hdr.timeout = timeout * 1000;
io_hdr.pack_id = (int)start_block;
if (diop && *diop)
io_hdr.flags |= SG_FLAG_DIRECT_IO;
retry:
memset(sense, 0, sense_len);
while (((res = ioctl(sg_fd, SG_IO, &io_hdr)) < 0) && (EINTR == errno));
if (res < 0) {
if (ENOMEM == errno) {
return PATH_UP;
}
return PATH_DOWN;
}
if ((0 == io_hdr.status) &&
(0 == io_hdr.host_status) &&
(0 == io_hdr.driver_status)) {
return PATH_UP;
} else {
int key = 0;
if (io_hdr.sb_len_wr > 3) {
if (sbb[0] == 0x72 || sbb[0] == 0x73)
key = sbb[1] & 0x0f;
else if (io_hdr.sb_len_wr > 13 &&
((sbb[0] & 0x7f) == 0x70 ||
(sbb[0] & 0x7f) == 0x71))
key = sbb[2] & 0x0f;
}
/*
* Retry if UNIT_ATTENTION check condition.
*/
if (key == 0x6) {
if (--retry_count)
goto retry;
}
return PATH_DOWN;
}
}
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