[stgt] [PATCH] Make the backing-store modules shared objects that are loaded at runtime
Dan Mick
dan.mick at inktank.com
Sat Aug 10 08:09:09 CEST 2013
I can confirm that, with all instances of 'rdb' changed to 'rbd', and
the obvious change to bs_rbd.c, this works for bs_rbd as well. If I'd
been more intelligent I'd have committed your patch locally before
hacking on it. It's late. :)
+1 on the idea and overall structure; it would be interesting in
particular to hear others' opinions about the choice of
/usr/lib/tgtd/backing-store, although it seems fine to me.
Ceph users would benefit greatly from the ability for the official
released packages (assuming the package maintainers will do it) to
contain the rbd backend without requiring compilation.
On 08/09/2013 10:47 PM, Dan Mick wrote:
> This would be super-cool, as it would allow building and distributing
> rbd support without requiring users of the package to install Ceph just
> to use stgt without Ceph.
>
> Some initial comments below:
>
> On 08/09/2013 04:02 PM, Ronnie Sahlberg wrote:
>> Turn most of TGTD into a shared library libtgt.so and install it under
>> $(PREFIX)/lib/tgtd
>>
>> Change the six backing stores bs_aio/null/rdb/rdwr/sg/ssc into shared
>> objects
>> and install them under $(PREFIX)/lib/tgtd/backing-store
>>
>> When tgtd is starting, have it traverse the directory for backing
>> stores and
>> automatically load and initialize all backing stores files that are
>> found.
>>
>> This allows for example to distribute bs_aio.so as a separate package
>> since it has additional dependencies (libaio) that tgtd itself does
>> not have
>> Similarly for bs_rdb.so.
>> This means that core TGTD can be distributed with minimal dependencies
>> and backends that add additional dependencies can be distributed
>> separately.
>>
>> Once we have this basics for a modularized TGTD later patches can
>> build ontop
>> of this and add features such as :
>> * list all modules and which luns are using them
>> * unload module if unused
>> * re-load module
>> But that can come in later patches. Lets get the basics in first.
>>
>> Signed-off-by: Ronnie Sahlberg <ronniesahlberg at gmail.com>
>> ---
>> usr/Makefile | 42 ++++++---
>> usr/bs.c | 46 +++++++++
>> usr/bs_aio.c | 2 +-
>> usr/bs_null.c | 2 +-
>> usr/bs_rdwr.c | 2 +-
>> usr/bs_sg.c | 2 +-
>> usr/bs_ssc.c | 2 +-
>
> No 2-line change to bs_rbd.c?
>
>> usr/target.c | 285
>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
>> usr/tgtd.c | 276
>> +-------------------------------------------------------
>> usr/tgtd.h | 2 +
>> 10 files changed, 360 insertions(+), 301 deletions(-)
>>
>> diff --git a/usr/Makefile b/usr/Makefile
>> index 453eb1a..5c76f43 100644
>> --- a/usr/Makefile
>> +++ b/usr/Makefile
>> @@ -1,4 +1,5 @@
>> sbindir ?= $(PREFIX)/sbin
>> +libdir ?= $(PREFIX)/lib/tgtd
>>
>> ifneq ($(shell test -e /usr/include/linux/signalfd.h && echo 1),)
>> CFLAGS += -DUSE_SIGNALFD
>> @@ -11,17 +12,14 @@ endif
>> TGTD_OBJS += $(addprefix iscsi/, conn.o param.o session.o \
>> iscsid.o target.o chap.o sha1.o md5.o transport.o iscsi_tcp.o \
>> isns.o)
>> -TGTD_OBJS += bs_rdwr.o
>>
>> ifneq ($(CEPH_RBD),)
>> -TGTD_OBJS += bs_rbd.o
>> -LIBS += -lrados -lrbd
>> +BS_OBJS += bs_rdb.so
>
> bs_rbd.so, not rdb
>
> It may seem weird to compile, but it *should* be enough to add package
> 'librbd1' (which will also pull in librados2) to allow the build with
> CEPH_RBD enabled. If Tomo agrees this patch is worthwhile, I'd sure
> like to see it go in with all bsdrvs supported.
>
>> endif
>>
>> ifneq ($(shell test -e /usr/include/sys/eventfd.h && test -e
>> /usr/include/libaio.h && echo 1),)
>> CFLAGS += -DUSE_EVENTFD
>> -TGTD_OBJS += bs_aio.o
>> -LIBS += -laio
>> +BS_OBJS += bs_aio.so
>> endif
>>
>> ifneq ($(ISCSI_RDMA),)
>> @@ -40,25 +38,32 @@ CFLAGS += -g -O2 -fno-strict-aliasing
>> endif
>> CFLAGS += -Wall -Wstrict-prototypes -fPIC
>> CFLAGS += -DTGT_VERSION=\"$(VERSION)$(EXTRAVERSION)\"
>> +CFLAGS += -DBSDIR=\"$(DESTDIR)$(libdir)/backing-store\"
>>
>> LIBS += -lpthread
>>
>> PROGRAMS += tgtd tgtadm tgtimg
>> -TGTD_OBJS += tgtd.o mgmt.o target.o scsi.o log.o driver.o util.o
>> work.o \
>> - concat_buf.o parser.o spc.o sbc.o mmc.o osd.o scc.o smc.o \
>> - ssc.o bs_ssc.o libssc.o \
>> - bs_null.o bs_sg.o bs.o libcrc32c.o
>> +TGTD_OBJS += tgtd.o
>> +LIBTGT_OBJS = bs.o \
>> + concat_buf.o driver.o libcrc32c.o libssc.o log.o mgmt.o mmc.o \
>> + osd.o parser.o sbc.o scc.o scsi.o smc.o spc.o ssc.o \
>> + target.o util.o work.o
>> +
>> +BS_OBJS += bs_null.so bs_rdwr.so bs_sg.so bs_ssc.so
>>
>> TGTD_DEP = $(TGTD_OBJS:.o=.d)
>>
>> .PHONY:all
>> -all: $(PROGRAMS)
>> +all: libtgt.so $(PROGRAMS) $(BS_OBJS)
>>
>> tgtd: $(TGTD_OBJS)
>> - $(CC) $^ -o $@ $(LIBS)
>> + $(CC) $^ -o $@ $(LIBS) libtgt.so
>>
>> -include $(TGTD_DEP)
>>
>> +libtgt.so: $(LIBTGT_OBJS)
>> + $(CC) -shared -fPIC -DPIC $^ -o $@ -ldl
>> +
>> TGTADM_OBJS = tgtadm.o concat_buf.o
>> TGTADM_DEP = $(TGTADM_OBJS:.o=.d)
>>
>> @@ -79,11 +84,24 @@ tgtimg: $(TGTIMG_OBJS)
>> $(CC) -c $(CFLAGS) $*.c -o $*.o
>> @$(CC) -MM $(CFLAGS) -MF $*.d -MT $*.o $*.c
>>
>> +%.so: %.c
>> + $(CC) -shared $(CFLAGS) $*.c -o $*.so
>> +
>> +bs_aio.so: bs_aio.c
>> + $(CC) -shared $(CFLAGS) bs_aio.c -o bs_aio.so -laio
>> +
>> +bs_rdb.so: bs_rdb.c
>> + $(CC) -shared $(CFLAGS) bs_rdb.c -o bs_rdb.so -lrados -lrbd
>> +
>> .PHONY: install
>> install: $(PROGRAMS)
>> install -d -m 755 $(DESTDIR)$(sbindir)
>> install -m 755 $(PROGRAMS) $(DESTDIR)$(sbindir)
>> + install -d -m 755 $(DESTDIR)$(libdir)/backing-store
>> + install -m 755 $(BS_OBJS) $(DESTDIR)$(libdir)/backing-store
>> + install -m 755 libtgt.so $(DESTDIR)$(libdir)
>> + ldconfig $(DESTDIR)$(libdir)
>>
>> .PHONY: clean
>> clean:
>> - rm -f *.[od] $(PROGRAMS) iscsi/*.[od] ibmvio/*.[od] fc/*.[od]
>> + rm -f *.[od] *.so $(PROGRAMS) iscsi/*.[od] ibmvio/*.[od] fc/*.[od]
>> diff --git a/usr/bs.c b/usr/bs.c
>> index 65c332e..7974e3a 100644
>> --- a/usr/bs.c
>> +++ b/usr/bs.c
>> @@ -19,6 +19,8 @@
>> * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
>> * 02110-1301 USA
>> */
>> +#include <dirent.h>
>> +#include <dlfcn.h>
>> #include <errno.h>
>> #include <string.h>
>> #include <inttypes.h>
>> @@ -307,10 +309,54 @@ destroy_cond_mutex:
>> return 1;
>> }
>>
>> +void update_lbppbe(struct scsi_lu *lu, int blksize)
>> +{
>> + lu->attrs.lbppbe = 0;
>> + while (blksize > (1U << lu->blk_shift)) {
>> + lu->attrs.lbppbe++;
>> + blksize >>= 1;
>> + }
>> +}
>> +
>> int bs_init(void)
>> {
>> + DIR *dir;
>> int ret;
>>
>> + dir = opendir(BSDIR);
>> + if (dir == NULL) {
>> + eprintf("could not open backing-store module directory %s\n",
>> + BSDIR);
>> + } else {
>> + struct dirent *dirent;
>> + void *handle;
>> + while ((dirent = readdir(dir))) {
>> + char *soname;
>> + void (*register_bs_module)(void);
>> +
>> + if (dirent->d_name[0] == '.') {
>> + continue;
>> + }
>> +
>> + asprintf(&soname, "%s/%s", BSDIR, dirent->d_name);
>> + handle = dlopen(soname, RTLD_NOW|RTLD_LOCAL);
>> + if (handle == NULL) {
>> + eprintf("failed to dlopen backing-store "
>> + "module %s error %s \n",
>> + soname, dlerror());
>> + continue;
>> + }
>> + register_bs_module = dlsym(handle, "register_bs_module");
>> + if (register_bs_module == NULL) {
>> + eprintf("could not find register_bs_module "
>> + "symbol in module %s\n",
>> + soname);
>> + continue;
>> + }
>> + register_bs_module();
>> + }
>> + closedir(dir);
>> + }
>> ret = bs_init_signalfd();
>> if (!ret) {
>> eprintf("use signalfd notification\n");
>> diff --git a/usr/bs_aio.c b/usr/bs_aio.c
>> index c0cbadd..cc59cf6 100644
>> --- a/usr/bs_aio.c
>> +++ b/usr/bs_aio.c
>> @@ -414,7 +414,7 @@ static struct backingstore_template aio_bst = {
>> .bs_cmd_submit = bs_aio_cmd_submit,
>> };
>>
>> -__attribute__((constructor)) static void bs_rdwr_constructor(void)
>> +void register_bs_module(void)
>> {
>> register_backingstore_template(&aio_bst);
>> }
>> diff --git a/usr/bs_null.c b/usr/bs_null.c
>> index d463f18..4dbe144 100644
>> --- a/usr/bs_null.c
>> +++ b/usr/bs_null.c
>> @@ -56,7 +56,7 @@ static struct backingstore_template null_bst = {
>> .bs_cmd_submit = bs_null_cmd_submit,
>> };
>>
>> -__attribute__((constructor)) static void bs_null_constructor(void)
>> +void register_bs_module(void)
>> {
>> register_backingstore_template(&null_bst);
>> }
>> diff --git a/usr/bs_rdwr.c b/usr/bs_rdwr.c
>> index 47d2d99..82807d1 100644
>> --- a/usr/bs_rdwr.c
>> +++ b/usr/bs_rdwr.c
>> @@ -423,7 +423,7 @@ static struct backingstore_template rdwr_bst = {
>> .bs_oflags_supported = O_SYNC | O_DIRECT,
>> };
>>
>> -__attribute__((constructor)) static void bs_rdwr_constructor(void)
>> +void register_bs_module(void)
>> {
>> register_backingstore_template(&rdwr_bst);
>> }
>> diff --git a/usr/bs_sg.c b/usr/bs_sg.c
>> index 5f1e687..43dc5f3 100644
>> --- a/usr/bs_sg.c
>> +++ b/usr/bs_sg.c
>> @@ -517,7 +517,7 @@ static struct device_type_template sg_template = {
>> .cmd_passthrough = bs_sg_rw,
>> };
>>
>> -__attribute__((constructor)) static void bs_sg_constructor(void)
>> +void register_bs_module(void)
>> {
>> register_backingstore_template(&sg_bst);
>> register_backingstore_template(&bsg_bst);
>> diff --git a/usr/bs_ssc.c b/usr/bs_ssc.c
>> index 117e274..98b84b5 100644
>> --- a/usr/bs_ssc.c
>> +++ b/usr/bs_ssc.c
>> @@ -702,7 +702,7 @@ static struct backingstore_template ssc_bst = {
>> .bs_cmd_submit = bs_thread_cmd_submit,
>> };
>>
>> -__attribute__((constructor)) static void bs_ssc_constructor(void)
>> +void register_bs_module(void)
>> {
>> register_backingstore_template(&ssc_bst);
>> }
>> diff --git a/usr/target.c b/usr/target.c
>> index b1729b3..b7872fb 100644
>> --- a/usr/target.c
>> +++ b/usr/target.c
>> @@ -19,6 +19,7 @@
>> * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
>> * 02110-1301 USA
>> */
>> +#include <ctype.h>
>> #include <errno.h>
>> #include <fcntl.h>
>> #include <inttypes.h>
>> @@ -27,8 +28,10 @@
>> #include <string.h>
>> #include <time.h>
>> #include <unistd.h>
>> +#include <sys/epoll.h>
>> #include <sys/socket.h>
>> #include <sys/time.h>
>> +#include <sys/wait.h>
>>
>> #include "list.h"
>> #include "util.h"
>> @@ -42,8 +45,11 @@
>> #include "spc.h"
>>
>> static LIST_HEAD(device_type_list);
>> +static LIST_HEAD(tgt_events_list);
>> +static LIST_HEAD(tgt_sched_events_list);
>>
>> static struct target global_target;
>> +int ep_fd;
>>
>> int device_type_register(struct device_type_template *t)
>> {
>> @@ -2411,15 +2417,6 @@ tgtadm_err lld_show(struct concat_buf *b)
>> return TGTADM_SUCCESS;
>> }
>>
>> -void update_lbppbe(struct scsi_lu *lu, int blksize)
>> -{
>> - lu->attrs.lbppbe = 0;
>> - while (blksize > (1U << lu->blk_shift)) {
>> - lu->attrs.lbppbe++;
>> - blksize >>= 1;
>> - }
>> -}
>> -
>> int is_system_available(void)
>> {
>> return (sys_state == TGT_SYSTEM_READY);
>> @@ -2430,6 +2427,276 @@ int is_system_inactive(void)
>> return list_empty(&target_list);
>> }
>>
>> +int tgt_event_add(int fd, int events, event_handler_t handler, void
>> *data)
>> +{
>> + struct epoll_event ev;
>> + struct event_data *tev;
>> + int err;
>> +
>> + tev = zalloc(sizeof(*tev));
>> + if (!tev)
>> + return -ENOMEM;
>> +
>> + tev->data = data;
>> + tev->handler = handler;
>> + tev->fd = fd;
>> +
>> + memset(&ev, 0, sizeof(ev));
>> + ev.events = events;
>> + ev.data.ptr = tev;
>> + err = epoll_ctl(ep_fd, EPOLL_CTL_ADD, fd, &ev);
>> + if (err) {
>> + eprintf("Cannot add fd, %m\n");
>> + free(tev);
>> + } else
>> + list_add(&tev->e_list, &tgt_events_list);
>> +
>> + return err;
>> +}
>> +
>> +static struct event_data *tgt_event_lookup(int fd)
>> +{
>> + struct event_data *tev;
>> +
>> + list_for_each_entry(tev, &tgt_events_list, e_list) {
>> + if (tev->fd == fd)
>> + return tev;
>> + }
>> + return NULL;
>> +}
>> +
>> +void tgt_event_del(int fd)
>> +{
>> + struct event_data *tev;
>> + int ret;
>> +
>> + tev = tgt_event_lookup(fd);
>> + if (!tev) {
>> + eprintf("Cannot find event %d\n", fd);
>> + return;
>> + }
>> +
>> + ret = epoll_ctl(ep_fd, EPOLL_CTL_DEL, fd, NULL);
>> + if (ret < 0)
>> + eprintf("fail to remove epoll event, %s\n", strerror(errno));
>> +
>> + list_del(&tev->e_list);
>> + free(tev);
>> +}
>> +
>> +int tgt_event_modify(int fd, int events)
>> +{
>> + struct epoll_event ev;
>> + struct event_data *tev;
>> +
>> + tev = tgt_event_lookup(fd);
>> + if (!tev) {
>> + eprintf("Cannot find event %d\n", fd);
>> + return -EINVAL;
>> + }
>> +
>> + memset(&ev, 0, sizeof(ev));
>> + ev.events = events;
>> + ev.data.ptr = tev;
>> +
>> + return epoll_ctl(ep_fd, EPOLL_CTL_MOD, fd, &ev);
>> +}
>> +
>> +void tgt_init_sched_event(struct event_data *evt,
>> + sched_event_handler_t sched_handler, void *data)
>> +{
>> + evt->sched_handler = sched_handler;
>> + evt->scheduled = 0;
>> + evt->data = data;
>> + INIT_LIST_HEAD(&evt->e_list);
>> +}
>> +
>> +void tgt_add_sched_event(struct event_data *evt)
>> +{
>> + if (!evt->scheduled) {
>> + evt->scheduled = 1;
>> + list_add_tail(&evt->e_list, &tgt_sched_events_list);
>> + }
>> +}
>> +
>> +void tgt_remove_sched_event(struct event_data *evt)
>> +{
>> + if (evt->scheduled) {
>> + evt->scheduled = 0;
>> + list_del_init(&evt->e_list);
>> + }
>> +}
>> +
>> +int tgt_exec_scheduled(void)
>> +{
>> + struct list_head *last_sched;
>> + struct event_data *tev, *tevn;
>> + int work_remains = 0;
>> +
>> + if (!list_empty(&tgt_sched_events_list)) {
>> + /* execute only work scheduled till now */
>> + last_sched = tgt_sched_events_list.prev;
>> + list_for_each_entry_safe(tev, tevn, &tgt_sched_events_list,
>> + e_list) {
>> + tgt_remove_sched_event(tev);
>> + tev->sched_handler(tev);
>> + if (&tev->e_list == last_sched)
>> + break;
>> + }
>> + if (!list_empty(&tgt_sched_events_list))
>> + work_remains = 1;
>> + }
>> + return work_remains;
>> +}
>> +
>> +/* strcpy, while eating multiple white spaces */
>> +static void str_spacecpy(char **dest, const char *src)
>> +{
>> + const char *s = src;
>> + char *d = *dest;
>> +
>> + while (*s) {
>> + if (isspace(*s)) {
>> + if (!*(s+1))
>> + break;
>> + if (isspace(*(s+1))) {
>> + s++;
>> + continue;
>> + }
>> + }
>> + *d++ = *s++;
>> + }
>> + *d = '\0';
>> +}
>> +
>> +int call_program(const char *cmd, void (*callback)(void *data, int
>> result),
>> + void *data, char *output, int op_len, int flags)
>> +{
>> + pid_t pid;
>> + int fds[2], ret, i;
>> + char *pos, arg[256];
>> + char *argv[sizeof(arg) / 2];
>> +
>> + i = 0;
>> + pos = arg;
>> + str_spacecpy(&pos, cmd);
>> + if (strchr(cmd, ' ')) {
>> + while (pos != '\0')
>> + argv[i++] = strsep(&pos, " ");
>> + } else
>> + argv[i++] = arg;
>> + argv[i] = NULL;
>> +
>> + ret = pipe(fds);
>> + if (ret < 0) {
>> + eprintf("pipe create failed for %s, %m\n", cmd);
>> + return ret;
>> + }
>> +
>> + dprintf("%s, pipe: %d %d\n", cmd, fds[0], fds[1]);
>> +
>> + pid = fork();
>> + if (pid < 0) {
>> + eprintf("fork failed for: %s, %m\n", cmd);
>> + close(fds[0]);
>> + close(fds[1]);
>> + return pid;
>> + }
>> +
>> + if (!pid) {
>> + close(1);
>> + ret = dup(fds[1]);
>> + if (ret < 0) {
>> + eprintf("dup failed for: %s, %m\n", cmd);
>> + exit(-1);
>> + }
>> + close(fds[0]);
>> + execv(argv[0], argv);
>> +
>> + eprintf("execv failed for: %s, %m\n", cmd);
>> + exit(-1);
>> + } else {
>> + struct timeval tv;
>> + fd_set rfds;
>> + int ret_sel;
>> +
>> + close(fds[1]);
>> + /* 0.1 second is okay, as the initiator will retry anyway */
>> + do {
>> + FD_ZERO(&rfds);
>> + FD_SET(fds[0], &rfds);
>> + tv.tv_sec = 0;
>> + tv.tv_usec = 100000;
>> + ret_sel = select(fds[0]+1, &rfds, NULL, NULL, &tv);
>> + } while (ret_sel < 0 && errno == EINTR);
>> + if (ret_sel <= 0) { /* error or timeout */
>> + eprintf("timeout on redirect callback, terminating "
>> + "child pid %d\n", pid);
>> + kill(pid, SIGTERM);
>> + }
>> + do {
>> + ret = waitpid(pid, &i, 0);
>> + } while (ret < 0 && errno == EINTR);
>> + if (ret < 0) {
>> + eprintf("waitpid failed for: %s, %m\n", cmd);
>> + close(fds[0]);
>> + return ret;
>> + }
>> + if (ret_sel > 0) {
>> + ret = read(fds[0], output, op_len);
>> + if (ret < 0) {
>> + eprintf("failed to get output from: %s\n", cmd);
>> + close(fds[0]);
>> + return ret;
>> + }
>> + }
>> +
>> + if (callback)
>> + callback(data, WEXITSTATUS(i));
>> + close(fds[0]);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +struct tgt_param {
>> + int (*parse_func)(char *);
>> + char *name;
>> +};
>> +
>> +static struct tgt_param params[64];
>> +
>> +int setup_param(char *name, int (*parser)(char *))
>> +{
>> + int i;
>> +
>> + for (i = 0; i < ARRAY_SIZE(params); i++)
>> + if (!params[i].name)
>> + break;
>> +
>> + if (i < ARRAY_SIZE(params)) {
>> + params[i].name = name;
>> + params[i].parse_func = parser;
>> +
>> + return 0;
>> + } else
>> + return -1;
>> +}
>> +
>> +int parse_params(char *name, char *p)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < ARRAY_SIZE(params) && params[i].name; i++) {
>> + if (!strcmp(name, params[i].name))
>> + return params[i].parse_func(p);
>> + }
>> +
>> + fprintf(stderr, "'%s' is an unknown option\n", name);
>> +
>> + return -1;
>> +}
>> +
>> static void __attribute__((constructor)) target_constructor(void)
>> {
>> static int global_target_aids[DEFAULT_NR_ACCOUNT];
>> diff --git a/usr/tgtd.c b/usr/tgtd.c
>> index f985510..3ef7220 100644
>> --- a/usr/tgtd.c
>> +++ b/usr/tgtd.c
>> @@ -30,11 +30,9 @@
>> #include <stdlib.h>
>> #include <string.h>
>> #include <unistd.h>
>> -#include <ctype.h>
>> #include <sys/resource.h>
>> #include <sys/epoll.h>
>> #include <sys/types.h>
>> -#include <sys/wait.h>
>> #include <sys/stat.h>
>>
>> #include "list.h"
>> @@ -44,12 +42,10 @@
>> #include "util.h"
>>
>> unsigned long pagesize, pageshift;
>> +extern int ep_fd;
>>
>> int system_active = 1;
>> -static int ep_fd;
>> static char program_name[] = "tgtd";
>> -static LIST_HEAD(tgt_events_list);
>> -static LIST_HEAD(tgt_sched_events_list);
>>
>> static struct option const long_options[] = {
>> {"foreground", no_argument, 0, 'f'},
>> @@ -174,238 +170,6 @@ set_rlimit:
>> return 0;
>> }
>>
>> -int tgt_event_add(int fd, int events, event_handler_t handler, void
>> *data)
>> -{
>> - struct epoll_event ev;
>> - struct event_data *tev;
>> - int err;
>> -
>> - tev = zalloc(sizeof(*tev));
>> - if (!tev)
>> - return -ENOMEM;
>> -
>> - tev->data = data;
>> - tev->handler = handler;
>> - tev->fd = fd;
>> -
>> - memset(&ev, 0, sizeof(ev));
>> - ev.events = events;
>> - ev.data.ptr = tev;
>> - err = epoll_ctl(ep_fd, EPOLL_CTL_ADD, fd, &ev);
>> - if (err) {
>> - eprintf("Cannot add fd, %m\n");
>> - free(tev);
>> - } else
>> - list_add(&tev->e_list, &tgt_events_list);
>> -
>> - return err;
>> -}
>> -
>> -static struct event_data *tgt_event_lookup(int fd)
>> -{
>> - struct event_data *tev;
>> -
>> - list_for_each_entry(tev, &tgt_events_list, e_list) {
>> - if (tev->fd == fd)
>> - return tev;
>> - }
>> - return NULL;
>> -}
>> -
>> -void tgt_event_del(int fd)
>> -{
>> - struct event_data *tev;
>> - int ret;
>> -
>> - tev = tgt_event_lookup(fd);
>> - if (!tev) {
>> - eprintf("Cannot find event %d\n", fd);
>> - return;
>> - }
>> -
>> - ret = epoll_ctl(ep_fd, EPOLL_CTL_DEL, fd, NULL);
>> - if (ret < 0)
>> - eprintf("fail to remove epoll event, %s\n", strerror(errno));
>> -
>> - list_del(&tev->e_list);
>> - free(tev);
>> -}
>> -
>> -int tgt_event_modify(int fd, int events)
>> -{
>> - struct epoll_event ev;
>> - struct event_data *tev;
>> -
>> - tev = tgt_event_lookup(fd);
>> - if (!tev) {
>> - eprintf("Cannot find event %d\n", fd);
>> - return -EINVAL;
>> - }
>> -
>> - memset(&ev, 0, sizeof(ev));
>> - ev.events = events;
>> - ev.data.ptr = tev;
>> -
>> - return epoll_ctl(ep_fd, EPOLL_CTL_MOD, fd, &ev);
>> -}
>> -
>> -void tgt_init_sched_event(struct event_data *evt,
>> - sched_event_handler_t sched_handler, void *data)
>> -{
>> - evt->sched_handler = sched_handler;
>> - evt->scheduled = 0;
>> - evt->data = data;
>> - INIT_LIST_HEAD(&evt->e_list);
>> -}
>> -
>> -void tgt_add_sched_event(struct event_data *evt)
>> -{
>> - if (!evt->scheduled) {
>> - evt->scheduled = 1;
>> - list_add_tail(&evt->e_list, &tgt_sched_events_list);
>> - }
>> -}
>> -
>> -void tgt_remove_sched_event(struct event_data *evt)
>> -{
>> - if (evt->scheduled) {
>> - evt->scheduled = 0;
>> - list_del_init(&evt->e_list);
>> - }
>> -}
>> -
>> -/* strcpy, while eating multiple white spaces */
>> -void str_spacecpy(char **dest, const char *src)
>> -{
>> - const char *s = src;
>> - char *d = *dest;
>> -
>> - while (*s) {
>> - if (isspace(*s)) {
>> - if (!*(s+1))
>> - break;
>> - if (isspace(*(s+1))) {
>> - s++;
>> - continue;
>> - }
>> - }
>> - *d++ = *s++;
>> - }
>> - *d = '\0';
>> -}
>> -
>> -int call_program(const char *cmd, void (*callback)(void *data, int
>> result),
>> - void *data, char *output, int op_len, int flags)
>> -{
>> - pid_t pid;
>> - int fds[2], ret, i;
>> - char *pos, arg[256];
>> - char *argv[sizeof(arg) / 2];
>> -
>> - i = 0;
>> - pos = arg;
>> - str_spacecpy(&pos, cmd);
>> - if (strchr(cmd, ' ')) {
>> - while (pos != '\0')
>> - argv[i++] = strsep(&pos, " ");
>> - } else
>> - argv[i++] = arg;
>> - argv[i] = NULL;
>> -
>> - ret = pipe(fds);
>> - if (ret < 0) {
>> - eprintf("pipe create failed for %s, %m\n", cmd);
>> - return ret;
>> - }
>> -
>> - dprintf("%s, pipe: %d %d\n", cmd, fds[0], fds[1]);
>> -
>> - pid = fork();
>> - if (pid < 0) {
>> - eprintf("fork failed for: %s, %m\n", cmd);
>> - close(fds[0]);
>> - close(fds[1]);
>> - return pid;
>> - }
>> -
>> - if (!pid) {
>> - close(1);
>> - ret = dup(fds[1]);
>> - if (ret < 0) {
>> - eprintf("dup failed for: %s, %m\n", cmd);
>> - exit(-1);
>> - }
>> - close(fds[0]);
>> - execv(argv[0], argv);
>> -
>> - eprintf("execv failed for: %s, %m\n", cmd);
>> - exit(-1);
>> - } else {
>> - struct timeval tv;
>> - fd_set rfds;
>> - int ret_sel;
>> -
>> - close(fds[1]);
>> - /* 0.1 second is okay, as the initiator will retry anyway */
>> - do {
>> - FD_ZERO(&rfds);
>> - FD_SET(fds[0], &rfds);
>> - tv.tv_sec = 0;
>> - tv.tv_usec = 100000;
>> - ret_sel = select(fds[0]+1, &rfds, NULL, NULL, &tv);
>> - } while (ret_sel < 0 && errno == EINTR);
>> - if (ret_sel <= 0) { /* error or timeout */
>> - eprintf("timeout on redirect callback, terminating "
>> - "child pid %d\n", pid);
>> - kill(pid, SIGTERM);
>> - }
>> - do {
>> - ret = waitpid(pid, &i, 0);
>> - } while (ret < 0 && errno == EINTR);
>> - if (ret < 0) {
>> - eprintf("waitpid failed for: %s, %m\n", cmd);
>> - close(fds[0]);
>> - return ret;
>> - }
>> - if (ret_sel > 0) {
>> - ret = read(fds[0], output, op_len);
>> - if (ret < 0) {
>> - eprintf("failed to get output from: %s\n", cmd);
>> - close(fds[0]);
>> - return ret;
>> - }
>> - }
>> -
>> - if (callback)
>> - callback(data, WEXITSTATUS(i));
>> - close(fds[0]);
>> - }
>> -
>> - return 0;
>> -}
>> -
>> -static int tgt_exec_scheduled(void)
>> -{
>> - struct list_head *last_sched;
>> - struct event_data *tev, *tevn;
>> - int work_remains = 0;
>> -
>> - if (!list_empty(&tgt_sched_events_list)) {
>> - /* execute only work scheduled till now */
>> - last_sched = tgt_sched_events_list.prev;
>> - list_for_each_entry_safe(tev, tevn, &tgt_sched_events_list,
>> - e_list) {
>> - tgt_remove_sched_event(tev);
>> - tev->sched_handler(tev);
>> - if (&tev->e_list == last_sched)
>> - break;
>> - }
>> - if (!list_empty(&tgt_sched_events_list))
>> - work_remains = 1;
>> - }
>> - return work_remains;
>> -}
>> -
>> static void event_loop(void)
>> {
>> int nevent, i, sched_remains, timeout;
>> @@ -471,44 +235,6 @@ static void lld_exit(void)
>> }
>> }
>>
>> -struct tgt_param {
>> - int (*parse_func)(char *);
>> - char *name;
>> -};
>> -
>> -static struct tgt_param params[64];
>> -
>> -int setup_param(char *name, int (*parser)(char *))
>> -{
>> - int i;
>> -
>> - for (i = 0; i < ARRAY_SIZE(params); i++)
>> - if (!params[i].name)
>> - break;
>> -
>> - if (i < ARRAY_SIZE(params)) {
>> - params[i].name = name;
>> - params[i].parse_func = parser;
>> -
>> - return 0;
>> - } else
>> - return -1;
>> -}
>> -
>> -static int parse_params(char *name, char *p)
>> -{
>> - int i;
>> -
>> - for (i = 0; i < ARRAY_SIZE(params) && params[i].name; i++) {
>> - if (!strcmp(name, params[i].name))
>> - return params[i].parse_func(p);
>> - }
>> -
>> - fprintf(stderr, "'%s' is an unknown option\n", name);
>> -
>> - return -1;
>> -}
>> -
>> int main(int argc, char **argv)
>> {
>> struct sigaction sa_old;
>> diff --git a/usr/tgtd.h b/usr/tgtd.h
>> index 484e6e9..0d4c6ae 100644
>> --- a/usr/tgtd.h
>> +++ b/usr/tgtd.h
>> @@ -295,6 +295,7 @@ extern void tgt_event_del(int fd);
>>
>> extern void tgt_add_sched_event(struct event_data *evt);
>> extern void tgt_remove_sched_event(struct event_data *evt);
>> +extern int tgt_exec_scheduled(void);
>>
>> extern int tgt_event_modify(int fd, int events);
>> extern int target_cmd_queue(int tid, struct scsi_cmd *cmd);
>> @@ -373,6 +374,7 @@ extern struct backingstore_template
>> *get_backingstore_template(const char *name)
>> extern int lld_init_one(int lld_index);
>>
>> extern int setup_param(char *name, int (*parser)(char *));
>> +extern int parse_params(char *name, char *p);
>>
>> extern int bs_init(void);
>>
>>
--
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