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Merge pull request #397 from pizhenwei/iscsi-discard-fix

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iscsi-discard: adapt block limits
This commit is contained in:
Ronnie Sahlberg
2023-08-14 12:57:23 +10:00
committed by GitHub
parent 7577ec589c 2794079fef
commit a2f9ee5d78
1 changed files with 90 additions and 19 deletions
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109
utils/iscsi-discard.c
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@@ -26,8 +26,61 @@
#include "iscsi.h"
#include "scsi-lowlevel.h"
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
const char *initiator = "iqn.2007-10.com.github:sahlberg:libiscsi:iscsi-discard";
/* query unmap/write zero max blocks */
static uint64_t inquiry_max_blocks(struct iscsi_context *iscsi, int lun, int zeroout)
{
struct scsi_task *task;
int full_size;
struct scsi_inquiry_block_limits *inq;
uint64_t max_blocks = 0;
/* See how big this inquiry data is */
task = iscsi_inquiry_sync(iscsi, lun, 1, SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS, 64);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr, "Inquiry command failed : %s\n", iscsi_get_error(iscsi));
exit(EIO);
}
full_size = scsi_datain_getfullsize(task);
if (full_size > task->datain.size) {
scsi_free_scsi_task(task);
/* we need more data for the full list */
if ((task = iscsi_inquiry_sync(iscsi, lun, 1, SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS, full_size)) == NULL) {
fprintf(stderr, "Inquiry command failed : %s\n", iscsi_get_error(iscsi));
exit(EIO);
}
}
inq = scsi_datain_unmarshall(task);
if (inq == NULL) {
fprintf(stderr, "failed to unmarshall inquiry datain blob\n");
exit(EIO);
}
if (zeroout) {
/* A MAXIMUM WRITE SAME LENGTH field set to zero indicates
that the device server does not report a limit on the number
of logical blocks that may be requested for a single
WRITE SAME command */
max_blocks = inq->max_ws_len;
if (!max_blocks)
max_blocks = (uint64_t)-1ULL;
} else {
/* A MAXIMUM UNMAP LBA COUNT field set to 0000_0000h indicates
that the device server does not implement the UNMAP command */
max_blocks = inq->max_unmap;
}
scsi_free_scsi_task(task);
return max_blocks;
}
void print_help(void)
{
fprintf(stderr, "Usage: iscsi_readcapacity16 [OPTION...] <iscsi-url>\n");
@@ -67,7 +120,7 @@ int main(int argc, char *argv[])
int debug = 0, zeroout = 0;
int option_index, c;
unsigned int block_length;
long long offset = 0, length = 0, capacity, lba, blocks;
uint64_t offset = 0, length = 0, capacity, lba, blocks, max_blocks;
struct scsi_task *task;
struct scsi_readcapacity16 *rc16;
int ret = EINVAL;
@@ -167,7 +220,7 @@ int main(int argc, char *argv[])
capacity = block_length * (rc16->returned_lba + 1);
if (offset > capacity) {
fprintf(stderr,"Offset(%lld) exceeds capacity(%lld)\n", offset, capacity);
fprintf(stderr,"Offset(%lu) exceeds capacity(%lu)\n", offset, capacity);
goto free_task;
}
@@ -178,31 +231,49 @@ int main(int argc, char *argv[])
/* free readcapacity16 task */
scsi_free_scsi_task(task);
max_blocks = inquiry_max_blocks(iscsi, iscsi_url->lun, zeroout);
if (!max_blocks) {
fprintf(stderr, "Operation not supported\n");
exit(EOPNOTSUPP);
}
lba = offset / block_length;
blocks = length / block_length;
if (zeroout) {
void *zerobuf = calloc(block_length, 1);
for (uint64_t endlba = lba + blocks; lba < endlba; ) {
uint64_t towrite = MIN(max_blocks, endlba - lba);
assert(zerobuf);
task = iscsi_writesame16_sync(iscsi, iscsi_url->lun, lba, zerobuf,
block_length, blocks, 0, 0, 0, 0);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr,"Failed to execute writesame16 command\n");
goto out;
}
} else {
struct unmap_list list;
if (zeroout) {
static void *zerobuf;
list.lba = lba;
list.num = blocks;
task = iscsi_unmap_sync(iscsi, iscsi_url->lun, 0, 0, &list, 1);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr,"Failed to execute unmap command\n");
goto out;
if (!zerobuf) {
zerobuf = calloc(block_length, 1);
assert(zerobuf);
}
task = iscsi_writesame16_sync(iscsi, iscsi_url->lun, lba, zerobuf,
block_length, towrite, 0, 0, 0, 0);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr,"Failed to execute writesame16 command\n");
goto out;
}
} else {
struct unmap_list list;
list.lba = lba;
list.num = towrite;
task = iscsi_unmap_sync(iscsi, iscsi_url->lun, 0, 0, &list, 1);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr,"Failed to execute unmap command\n");
goto out;
}
}
lba += towrite;
scsi_free_scsi_task(task);
}
ret = 0;
goto out;
free_task:
scsi_free_scsi_task(task);