[stgt] [PATCH] Make the backing-store modules shared objects that are loaded at runtime
ronnie sahlberg
ronniesahlberg at gmail.com
Sat Aug 17 19:20:30 CEST 2013
Tomo, ping ?
On Tue, Aug 13, 2013 at 8:10 AM, ronnie sahlberg
<ronniesahlberg at gmail.com> wrote:
> Tomo ?
>
> On Sat, Aug 10, 2013 at 2:37 AM, ronnie sahlberg
> <ronniesahlberg at gmail.com> wrote:
>> On Fri, Aug 9, 2013 at 11:09 PM, Dan Mick <dan.mick at inktank.com> wrote:
>>> 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. :)
>>
>> Thanks. I have updated the patch.
>>>
>>> +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.
>>
>> I have no strong feelings about where to store the modules so if
>> anyone has a better suggestion for the directory, please let me know
>> and I'll change it.
>>
>>
>>>
>>> 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.
>>
>> Yes. It would also be really neat if at a later stage one could
>> unload/reload a bs module at runtime. This I think would greatly
>> improve the experience for people that are developing and testing
>> backends.
>>
>>>
>>>
>>> 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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