9464d250b6
Increase the block-layer backend maximum number of requests to match the AHCI command queue depth.
427 lines
8.6 KiB
C
427 lines
8.6 KiB
C
/*-
|
|
* Copyright (c) 2013 Peter Grehan <grehan@freebsd.org>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/queue.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/disk.h>
|
|
|
|
#include <assert.h>
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <pthread.h>
|
|
#include <pthread_np.h>
|
|
#include <unistd.h>
|
|
|
|
#include "bhyverun.h"
|
|
#include "block_if.h"
|
|
|
|
#define BLOCKIF_SIG 0xb109b109
|
|
|
|
#define BLOCKIF_MAXREQ 32
|
|
|
|
enum blockop {
|
|
BOP_READ,
|
|
BOP_WRITE,
|
|
BOP_FLUSH,
|
|
BOP_CANCEL
|
|
};
|
|
|
|
enum blockstat {
|
|
BST_FREE,
|
|
BST_INUSE
|
|
};
|
|
|
|
struct blockif_elem {
|
|
TAILQ_ENTRY(blockif_elem) be_link;
|
|
struct blockif_req *be_req;
|
|
enum blockop be_op;
|
|
enum blockstat be_status;
|
|
};
|
|
|
|
struct blockif_ctxt {
|
|
int bc_magic;
|
|
int bc_fd;
|
|
int bc_rdonly;
|
|
off_t bc_size;
|
|
int bc_sectsz;
|
|
pthread_t bc_btid;
|
|
pthread_mutex_t bc_mtx;
|
|
pthread_cond_t bc_cond;
|
|
int bc_closing;
|
|
|
|
/* Request elements and free/inuse queues */
|
|
TAILQ_HEAD(, blockif_elem) bc_freeq;
|
|
TAILQ_HEAD(, blockif_elem) bc_inuseq;
|
|
u_int bc_req_count;
|
|
struct blockif_elem bc_reqs[BLOCKIF_MAXREQ];
|
|
};
|
|
|
|
static int
|
|
blockif_enqueue(struct blockif_ctxt *bc, struct blockif_req *breq,
|
|
enum blockop op)
|
|
{
|
|
struct blockif_elem *be;
|
|
|
|
assert(bc->bc_req_count < BLOCKIF_MAXREQ);
|
|
|
|
be = TAILQ_FIRST(&bc->bc_freeq);
|
|
assert(be != NULL);
|
|
assert(be->be_status == BST_FREE);
|
|
|
|
TAILQ_REMOVE(&bc->bc_freeq, be, be_link);
|
|
be->be_status = BST_INUSE;
|
|
be->be_req = breq;
|
|
be->be_op = op;
|
|
TAILQ_INSERT_TAIL(&bc->bc_inuseq, be, be_link);
|
|
|
|
bc->bc_req_count++;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
blockif_dequeue(struct blockif_ctxt *bc, struct blockif_elem *el)
|
|
{
|
|
struct blockif_elem *be;
|
|
|
|
if (bc->bc_req_count == 0)
|
|
return (ENOENT);
|
|
|
|
be = TAILQ_FIRST(&bc->bc_inuseq);
|
|
assert(be != NULL);
|
|
assert(be->be_status == BST_INUSE);
|
|
*el = *be;
|
|
|
|
TAILQ_REMOVE(&bc->bc_inuseq, be, be_link);
|
|
be->be_status = BST_FREE;
|
|
be->be_req = NULL;
|
|
TAILQ_INSERT_TAIL(&bc->bc_freeq, be, be_link);
|
|
|
|
bc->bc_req_count--;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
blockif_proc(struct blockif_ctxt *bc, struct blockif_elem *be)
|
|
{
|
|
struct blockif_req *br;
|
|
int err;
|
|
|
|
br = be->be_req;
|
|
err = 0;
|
|
|
|
switch (be->be_op) {
|
|
case BOP_READ:
|
|
if (preadv(bc->bc_fd, br->br_iov, br->br_iovcnt,
|
|
br->br_offset) < 0)
|
|
err = errno;
|
|
break;
|
|
case BOP_WRITE:
|
|
if (bc->bc_rdonly)
|
|
err = EROFS;
|
|
else if (pwritev(bc->bc_fd, br->br_iov, br->br_iovcnt,
|
|
br->br_offset) < 0)
|
|
err = errno;
|
|
break;
|
|
case BOP_FLUSH:
|
|
break;
|
|
case BOP_CANCEL:
|
|
err = EINTR;
|
|
break;
|
|
default:
|
|
err = EINVAL;
|
|
break;
|
|
}
|
|
|
|
(*br->br_callback)(br, err);
|
|
}
|
|
|
|
static void *
|
|
blockif_thr(void *arg)
|
|
{
|
|
struct blockif_ctxt *bc;
|
|
struct blockif_elem req;
|
|
|
|
bc = arg;
|
|
|
|
for (;;) {
|
|
pthread_mutex_lock(&bc->bc_mtx);
|
|
while (!blockif_dequeue(bc, &req)) {
|
|
pthread_mutex_unlock(&bc->bc_mtx);
|
|
blockif_proc(bc, &req);
|
|
pthread_mutex_lock(&bc->bc_mtx);
|
|
}
|
|
pthread_cond_wait(&bc->bc_cond, &bc->bc_mtx);
|
|
pthread_mutex_unlock(&bc->bc_mtx);
|
|
|
|
/*
|
|
* Check ctxt status here to see if exit requested
|
|
*/
|
|
if (bc->bc_closing)
|
|
pthread_exit(NULL);
|
|
}
|
|
|
|
/* Not reached */
|
|
return (NULL);
|
|
}
|
|
|
|
struct blockif_ctxt *
|
|
blockif_open(const char *optstr, const char *ident)
|
|
{
|
|
char tname[MAXCOMLEN + 1];
|
|
char *nopt, *xopts;
|
|
struct blockif_ctxt *bc;
|
|
struct stat sbuf;
|
|
off_t size;
|
|
int extra, fd, i, sectsz;
|
|
int nocache, sync, ro;
|
|
|
|
nocache = 0;
|
|
sync = 0;
|
|
ro = 0;
|
|
|
|
/*
|
|
* The first element in the optstring is always a pathname.
|
|
* Optional elements follow
|
|
*/
|
|
nopt = strdup(optstr);
|
|
for (xopts = strtok(nopt, ",");
|
|
xopts != NULL;
|
|
xopts = strtok(NULL, ",")) {
|
|
if (!strcmp(xopts, "nocache"))
|
|
nocache = 1;
|
|
else if (!strcmp(xopts, "sync"))
|
|
sync = 1;
|
|
else if (!strcmp(xopts, "ro"))
|
|
ro = 1;
|
|
}
|
|
|
|
extra = 0;
|
|
if (nocache)
|
|
extra |= O_DIRECT;
|
|
if (sync)
|
|
extra |= O_SYNC;
|
|
|
|
fd = open(nopt, (ro ? O_RDONLY : O_RDWR) | extra);
|
|
if (fd < 0 && !ro) {
|
|
/* Attempt a r/w fail with a r/o open */
|
|
fd = open(nopt, O_RDONLY | extra);
|
|
ro = 1;
|
|
}
|
|
|
|
if (fd < 0) {
|
|
perror("Could not open backing file");
|
|
return (NULL);
|
|
}
|
|
|
|
if (fstat(fd, &sbuf) < 0) {
|
|
perror("Could not stat backing file");
|
|
close(fd);
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Deal with raw devices
|
|
*/
|
|
size = sbuf.st_size;
|
|
sectsz = DEV_BSIZE;
|
|
if (S_ISCHR(sbuf.st_mode)) {
|
|
if (ioctl(fd, DIOCGMEDIASIZE, &size) < 0 ||
|
|
ioctl(fd, DIOCGSECTORSIZE, §sz)) {
|
|
perror("Could not fetch dev blk/sector size");
|
|
close(fd);
|
|
return (NULL);
|
|
}
|
|
assert(size != 0);
|
|
assert(sectsz != 0);
|
|
}
|
|
|
|
bc = malloc(sizeof(struct blockif_ctxt));
|
|
if (bc == NULL) {
|
|
close(fd);
|
|
return (NULL);
|
|
}
|
|
|
|
memset(bc, 0, sizeof(*bc));
|
|
bc->bc_magic = BLOCKIF_SIG;
|
|
bc->bc_fd = fd;
|
|
bc->bc_size = size;
|
|
bc->bc_sectsz = sectsz;
|
|
pthread_mutex_init(&bc->bc_mtx, NULL);
|
|
pthread_cond_init(&bc->bc_cond, NULL);
|
|
TAILQ_INIT(&bc->bc_freeq);
|
|
TAILQ_INIT(&bc->bc_inuseq);
|
|
bc->bc_req_count = 0;
|
|
for (i = 0; i < BLOCKIF_MAXREQ; i++) {
|
|
bc->bc_reqs[i].be_status = BST_FREE;
|
|
TAILQ_INSERT_HEAD(&bc->bc_freeq, &bc->bc_reqs[i], be_link);
|
|
}
|
|
|
|
pthread_create(&bc->bc_btid, NULL, blockif_thr, bc);
|
|
|
|
snprintf(tname, sizeof(tname), "blk-%s", ident);
|
|
pthread_set_name_np(bc->bc_btid, tname);
|
|
|
|
return (bc);
|
|
}
|
|
|
|
static int
|
|
blockif_request(struct blockif_ctxt *bc, struct blockif_req *breq,
|
|
enum blockop op)
|
|
{
|
|
int err;
|
|
|
|
err = 0;
|
|
|
|
pthread_mutex_lock(&bc->bc_mtx);
|
|
if (bc->bc_req_count < BLOCKIF_MAXREQ) {
|
|
/*
|
|
* Enqueue and inform the block i/o thread
|
|
* that there is work available
|
|
*/
|
|
blockif_enqueue(bc, breq, op);
|
|
pthread_cond_signal(&bc->bc_cond);
|
|
} else {
|
|
/*
|
|
* Callers are not allowed to enqueue more than
|
|
* the specified blockif queue limit. Return an
|
|
* error to indicate that the queue length has been
|
|
* exceeded.
|
|
*/
|
|
err = E2BIG;
|
|
}
|
|
pthread_mutex_unlock(&bc->bc_mtx);
|
|
|
|
return (err);
|
|
}
|
|
|
|
int
|
|
blockif_read(struct blockif_ctxt *bc, struct blockif_req *breq)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (blockif_request(bc, breq, BOP_READ));
|
|
}
|
|
|
|
int
|
|
blockif_write(struct blockif_ctxt *bc, struct blockif_req *breq)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (blockif_request(bc, breq, BOP_WRITE));
|
|
}
|
|
|
|
int
|
|
blockif_flush(struct blockif_ctxt *bc, struct blockif_req *breq)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (blockif_request(bc, breq, BOP_FLUSH));
|
|
}
|
|
|
|
int
|
|
blockif_cancel(struct blockif_ctxt *bc, struct blockif_req *breq)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (blockif_request(bc, breq, BOP_CANCEL));
|
|
}
|
|
|
|
int
|
|
blockif_close(struct blockif_ctxt *bc)
|
|
{
|
|
void *jval;
|
|
int err;
|
|
|
|
err = 0;
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
|
|
/*
|
|
* Stop the block i/o thread
|
|
*/
|
|
bc->bc_closing = 1;
|
|
pthread_cond_signal(&bc->bc_cond);
|
|
pthread_join(bc->bc_btid, &jval);
|
|
|
|
/* XXX Cancel queued i/o's ??? */
|
|
|
|
/*
|
|
* Release resources
|
|
*/
|
|
bc->bc_magic = 0;
|
|
close(bc->bc_fd);
|
|
free(bc);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Accessors
|
|
*/
|
|
off_t
|
|
blockif_size(struct blockif_ctxt *bc)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (bc->bc_size);
|
|
}
|
|
|
|
int
|
|
blockif_sectsz(struct blockif_ctxt *bc)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (bc->bc_sectsz);
|
|
}
|
|
|
|
int
|
|
blockif_queuesz(struct blockif_ctxt *bc)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (BLOCKIF_MAXREQ);
|
|
}
|
|
|
|
int
|
|
blockif_is_ro(struct blockif_ctxt *bc)
|
|
{
|
|
|
|
assert(bc->bc_magic == BLOCKIF_SIG);
|
|
return (bc->bc_rdonly);
|
|
}
|