[Qemu-devel] [PULL 0/12] qemu-ga: error handling improvements and fsfreeze hooks

[Qemu-devel] [PULL 0/12] qemu-ga: error handling improvements and fsfreeze hooks

[Michael Roth]

The following changes since commit 4b274b1603e1d15ef51aedc8b6b7ebbae0b555ce:

  Merge remote-tracking branch 'afaerber/qom-cpu' into staging (2013-01-08 15:15:57 -0600)

are available in the git repository at:


  git://github.com/mdroth/qemu.git qga-pull-1-8-2013

for you to fetch changes up to 96610da210697a1f33669d8bec0cb7b944d3a516:

  qemu-ga: sample fsfreeze hooks (2013-01-08 16:38:12 -0600)

----------------------------------------------------------------
Luiz Capitulino (10):
      qemu-ga: guest_file_handle_find(): take an Error argument
      qemu-ga: qmp_guest_file_close(): fix fclose() error check
      qemu-ga: qmp_guest_file_*: improve error reporting
      qemu-ga: qmp_guest_shutdown(): improve error reporting
      qemu-ga: build_fs_mount_list(): take an Error argument
      qemu-ga: qmp_guest_fsfreeze_*(): get rid of sprintf() + error_set()
      qemu-ga: qmp_guest_fstrim(): get rid of sprintf() + error_set()
      qemu-ga: qmp_guest_network_get_interfaces(): get rid of snprintf() + error_set()
      qemu-ga: bios_supports_mode(): improve error reporting
      qemu-ga: guest_suspend(): improve error reporting

Tomoki Sekiyama (2):
      qemu-ga: execute hook to quiesce the guest on fsfreeze-freeze/thaw
      qemu-ga: sample fsfreeze hooks

 .gitignore                                         |    1 +
 Makefile                                           |    2 +-
 qga/commands-posix.c                               |  313 +++++++++++++-------
 qga/guest-agent-core.h                             |    1 +
 qga/main.c                                         |   48 ++-
 scripts/qemu-guest-agent/fsfreeze-hook             |   33 +++
 .../fsfreeze-hook.d/mysql-flush.sh.sample          |   56 ++++
 7 files changed, 342 insertions(+), 112 deletions(-)
 create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook
 create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample

[Qemu-devel] [PATCH 01/12] qemu-ga: guest_file_handle_find(): take an Error argument

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>

*Fixed missing space character in error message

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index a657201..bbef66d 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -111,7 +111,7 @@ static void guest_file_handle_add(FILE *fh)
     QTAILQ_INSERT_TAIL(&guest_file_state.filehandles, gfh, next);
 }
 
-static GuestFileHandle *guest_file_handle_find(int64_t id)
+static GuestFileHandle *guest_file_handle_find(int64_t id, Error **err)
 {
     GuestFileHandle *gfh;
 
@@ -122,6 +122,7 @@ static GuestFileHandle *guest_file_handle_find(int64_t id)
         }
     }
 
+    error_setg(err, "handle '%" PRId64 "' has not been found", id);
     return NULL;
 }
 
@@ -160,12 +161,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode, E
 
 void qmp_guest_file_close(int64_t handle, Error **err)
 {
-    GuestFileHandle *gfh = guest_file_handle_find(handle);
+    GuestFileHandle *gfh = guest_file_handle_find(handle, err);
     int ret;
 
     slog("guest-file-close called, handle: %ld", handle);
     if (!gfh) {
-        error_set(err, QERR_FD_NOT_FOUND, "handle");
         return;
     }
 
@@ -182,14 +182,13 @@ void qmp_guest_file_close(int64_t handle, Error **err)
 struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count,
                                           int64_t count, Error **err)
 {
-    GuestFileHandle *gfh = guest_file_handle_find(handle);
+    GuestFileHandle *gfh = guest_file_handle_find(handle, err);
     GuestFileRead *read_data = NULL;
     guchar *buf;
     FILE *fh;
     size_t read_count;
 
     if (!gfh) {
-        error_set(err, QERR_FD_NOT_FOUND, "handle");
         return NULL;
     }
 
@@ -228,11 +227,10 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64,
     guchar *buf;
     gsize buf_len;
     int write_count;
-    GuestFileHandle *gfh = guest_file_handle_find(handle);
+    GuestFileHandle *gfh = guest_file_handle_find(handle, err);
     FILE *fh;
 
     if (!gfh) {
-        error_set(err, QERR_FD_NOT_FOUND, "handle");
         return NULL;
     }
 
@@ -265,13 +263,12 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64,
 struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset,
                                           int64_t whence, Error **err)
 {
-    GuestFileHandle *gfh = guest_file_handle_find(handle);
+    GuestFileHandle *gfh = guest_file_handle_find(handle, err);
     GuestFileSeek *seek_data = NULL;
     FILE *fh;
     int ret;
 
     if (!gfh) {
-        error_set(err, QERR_FD_NOT_FOUND, "handle");
         return NULL;
     }
 
@@ -291,12 +288,11 @@ struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset,
 
 void qmp_guest_file_flush(int64_t handle, Error **err)
 {
-    GuestFileHandle *gfh = guest_file_handle_find(handle);
+    GuestFileHandle *gfh = guest_file_handle_find(handle, err);
     FILE *fh;
     int ret;
 
     if (!gfh) {
-        error_set(err, QERR_FD_NOT_FOUND, "handle");
         return;
     }
 
-- 
1.7.9.5

[Qemu-devel] [PATCH 02/12] qemu-ga: qmp_guest_file_close(): fix fclose() error check

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

fclose() returns EOF on error.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index bbef66d..ebb58be 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -170,7 +170,7 @@ void qmp_guest_file_close(int64_t handle, Error **err)
     }
 
     ret = fclose(gfh->fh);
-    if (ret == -1) {
+    if (ret == EOF) {
         error_set(err, QERR_QGA_COMMAND_FAILED, "fclose() failed");
         return;
     }
-- 
1.7.9.5

[Qemu-devel] [PATCH 03/12] qemu-ga: qmp_guest_file_*: improve error reporting

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Use error_setg_errno() when possible with an improved error description.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index ebb58be..d5f2dcd 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -138,7 +138,8 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode, E
     slog("guest-file-open called, filepath: %s, mode: %s", path, mode);
     fh = fopen(path, mode);
     if (!fh) {
-        error_set(err, QERR_OPEN_FILE_FAILED, path);
+        error_setg_errno(err, errno, "failed to open file '%s' (mode: '%s')",
+                         path, mode);
         return -1;
     }
 
@@ -149,7 +150,8 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode, E
     ret = fcntl(fd, F_GETFL);
     ret = fcntl(fd, F_SETFL, ret | O_NONBLOCK);
     if (ret == -1) {
-        error_set(err, QERR_QGA_COMMAND_FAILED, "fcntl() failed");
+        error_setg_errno(err, errno, "failed to make file '%s' non-blocking",
+                         path);
         fclose(fh);
         return -1;
     }
@@ -171,7 +173,7 @@ void qmp_guest_file_close(int64_t handle, Error **err)
 
     ret = fclose(gfh->fh);
     if (ret == EOF) {
-        error_set(err, QERR_QGA_COMMAND_FAILED, "fclose() failed");
+        error_setg_errno(err, errno, "failed to close handle");
         return;
     }
 
@@ -195,7 +197,8 @@ struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count,
     if (!has_count) {
         count = QGA_READ_COUNT_DEFAULT;
     } else if (count < 0) {
-        error_set(err, QERR_INVALID_PARAMETER, "count");
+        error_setg(err, "value '%" PRId64 "' is invalid for argument count",
+                   count);
         return NULL;
     }
 
@@ -203,8 +206,8 @@ struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count,
     buf = g_malloc0(count+1);
     read_count = fread(buf, 1, count, fh);
     if (ferror(fh)) {
+        error_setg_errno(err, errno, "failed to read file");
         slog("guest-file-read failed, handle: %ld", handle);
-        error_set(err, QERR_QGA_COMMAND_FAILED, "fread() failed");
     } else {
         buf[read_count] = 0;
         read_data = g_malloc0(sizeof(GuestFileRead));
@@ -240,15 +243,16 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64,
     if (!has_count) {
         count = buf_len;
     } else if (count < 0 || count > buf_len) {
+        error_setg(err, "value '%" PRId64 "' is invalid for argument count",
+                   count);
         g_free(buf);
-        error_set(err, QERR_INVALID_PARAMETER, "count");
         return NULL;
     }
 
     write_count = fwrite(buf, 1, count, fh);
     if (ferror(fh)) {
+        error_setg_errno(err, errno, "failed to write to file");
         slog("guest-file-write failed, handle: %ld", handle);
-        error_set(err, QERR_QGA_COMMAND_FAILED, "fwrite() error");
     } else {
         write_data = g_malloc0(sizeof(GuestFileWrite));
         write_data->count = write_count;
@@ -275,7 +279,7 @@ struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset,
     fh = gfh->fh;
     ret = fseek(fh, offset, whence);
     if (ret == -1) {
-        error_set(err, QERR_QGA_COMMAND_FAILED, strerror(errno));
+        error_setg_errno(err, errno, "failed to seek file");
     } else {
         seek_data = g_malloc0(sizeof(GuestFileRead));
         seek_data->position = ftell(fh);
@@ -299,7 +303,7 @@ void qmp_guest_file_flush(int64_t handle, Error **err)
     fh = gfh->fh;
     ret = fflush(fh);
     if (ret == EOF) {
-        error_set(err, QERR_QGA_COMMAND_FAILED, strerror(errno));
+        error_setg_errno(err, errno, "failed to flush file");
     }
 }
 
-- 
1.7.9.5

[Qemu-devel] [PATCH 04/12] qemu-ga: qmp_guest_shutdown(): improve error reporting

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Most errors are QERR_UNDEFINED_ERROR. Also, adds ga_wait_child() as
a future commit will use it too.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   48 ++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 38 insertions(+), 10 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index d5f2dcd..247e8dc 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -46,10 +46,29 @@ extern char **environ;
 #endif
 #endif
 
+static void ga_wait_child(pid_t pid, int *status, Error **err)
+{
+    pid_t rpid;
+
+    *status = 0;
+
+    do {
+        rpid = waitpid(pid, status, 0);
+    } while (rpid == -1 && errno == EINTR);
+
+    if (rpid == -1) {
+        error_setg_errno(err, errno, "failed to wait for child (pid: %d)", pid);
+        return;
+    }
+
+    g_assert(rpid == pid);
+}
+
 void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err)
 {
     const char *shutdown_flag;
-    pid_t rpid, pid;
+    Error *local_err = NULL;
+    pid_t pid;
     int status;
 
     slog("guest-shutdown called, mode: %s", mode);
@@ -60,8 +79,8 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err)
     } else if (strcmp(mode, "reboot") == 0) {
         shutdown_flag = "-r";
     } else {
-        error_set(err, QERR_INVALID_PARAMETER_VALUE, "mode",
-                  "halt|powerdown|reboot");
+        error_setg(err,
+                   "mode is invalid (valid values are: halt|powerdown|reboot");
         return;
     }
 
@@ -77,18 +96,27 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err)
                "hypervisor initiated shutdown", (char*)NULL, environ);
         _exit(EXIT_FAILURE);
     } else if (pid < 0) {
-        goto exit_err;
+        error_setg_errno(err, errno, "failed to create child process");
+        return;
     }
 
-    do {
-        rpid = waitpid(pid, &status, 0);
-    } while (rpid == -1 && errno == EINTR);
-    if (rpid == pid && WIFEXITED(status) && !WEXITSTATUS(status)) {
+    ga_wait_child(pid, &status, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
         return;
     }
 
-exit_err:
-    error_set(err, QERR_UNDEFINED_ERROR);
+    if (!WIFEXITED(status)) {
+        error_setg(err, "child process has terminated abnormally");
+        return;
+    }
+
+    if (WEXITSTATUS(status)) {
+        error_setg(err, "child process has failed to shutdown");
+        return;
+    }
+
+    /* succeded */
 }
 
 typedef struct GuestFileHandle {
-- 
1.7.9.5

[Qemu-devel] [PATCH 05/12] qemu-ga: build_fs_mount_list(): take an Error argument

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 247e8dc..f7b85b2 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -371,7 +371,7 @@ static void free_fs_mount_list(FsMountList *mounts)
 /*
  * Walk the mount table and build a list of local file systems
  */
-static int build_fs_mount_list(FsMountList *mounts)
+static void build_fs_mount_list(FsMountList *mounts, Error **err)
 {
     struct mntent *ment;
     FsMount *mount;
@@ -380,8 +380,8 @@ static int build_fs_mount_list(FsMountList *mounts)
 
     fp = setmntent(mtab, "r");
     if (!fp) {
-        g_warning("fsfreeze: unable to read mtab");
-        return -1;
+        error_setg(err, "failed to open mtab file: '%s'", mtab);
+        return;
     }
 
     while ((ment = getmntent(fp))) {
@@ -405,8 +405,6 @@ static int build_fs_mount_list(FsMountList *mounts)
     }
 
     endmntent(fp);
-
-    return 0;
 }
 #endif
 
@@ -433,15 +431,17 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
     int ret = 0, i = 0;
     FsMountList mounts;
     struct FsMount *mount;
+    Error *local_err = NULL;
     int fd;
     char err_msg[512];
 
     slog("guest-fsfreeze called");
 
     QTAILQ_INIT(&mounts);
-    ret = build_fs_mount_list(&mounts);
-    if (ret < 0) {
-        return ret;
+    build_fs_mount_list(&mounts, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
+        return -1;
     }
 
     /* cannot risk guest agent blocking itself on a write in this state */
@@ -498,12 +498,12 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err)
     FsMountList mounts;
     FsMount *mount;
     int fd, i = 0, logged;
+    Error *local_err = NULL;
 
     QTAILQ_INIT(&mounts);
-    ret = build_fs_mount_list(&mounts);
-    if (ret) {
-        error_set(err, QERR_QGA_COMMAND_FAILED,
-                  "failed to enumerate filesystems");
+    build_fs_mount_list(&mounts, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
         return 0;
     }
 
@@ -568,6 +568,7 @@ void qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **err)
     FsMountList mounts;
     struct FsMount *mount;
     int fd;
+    Error *local_err = NULL;
     char err_msg[512];
     struct fstrim_range r = {
         .start = 0,
@@ -578,8 +579,9 @@ void qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **err)
     slog("guest-fstrim called");
 
     QTAILQ_INIT(&mounts);
-    ret = build_fs_mount_list(&mounts);
-    if (ret < 0) {
+    build_fs_mount_list(&mounts, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
         return;
     }
 
-- 
1.7.9.5

[Qemu-devel] [PATCH 06/12] qemu-ga: qmp_guest_fsfreeze_*(): get rid of sprintf() + error_set()

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Convert them to error_setg_errno().

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index f7b85b2..9ad2891 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -433,7 +433,6 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
     struct FsMount *mount;
     Error *local_err = NULL;
     int fd;
-    char err_msg[512];
 
     slog("guest-fsfreeze called");
 
@@ -450,9 +449,7 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
     QTAILQ_FOREACH(mount, &mounts, next) {
         fd = qemu_open(mount->dirname, O_RDONLY);
         if (fd == -1) {
-            sprintf(err_msg, "failed to open %s, %s", mount->dirname,
-                    strerror(errno));
-            error_set(err, QERR_QGA_COMMAND_FAILED, err_msg);
+            error_setg_errno(err, errno, "failed to open %s", mount->dirname);
             goto error;
         }
 
@@ -468,9 +465,8 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
         ret = ioctl(fd, FIFREEZE);
         if (ret == -1) {
             if (errno != EOPNOTSUPP) {
-                sprintf(err_msg, "failed to freeze %s, %s",
-                        mount->dirname, strerror(errno));
-                error_set(err, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(err, errno, "failed to freeze %s",
+                                 mount->dirname);
                 close(fd);
                 goto error;
             }
-- 
1.7.9.5

[Qemu-devel] [PATCH 07/12] qemu-ga: qmp_guest_fstrim(): get rid of sprintf() + error_set()

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Convert them to error_setg_errno().

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 9ad2891..fa786e5 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -565,7 +565,6 @@ void qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **err)
     struct FsMount *mount;
     int fd;
     Error *local_err = NULL;
-    char err_msg[512];
     struct fstrim_range r = {
         .start = 0,
         .len = -1,
@@ -584,9 +583,7 @@ void qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **err)
     QTAILQ_FOREACH(mount, &mounts, next) {
         fd = qemu_open(mount->dirname, O_RDONLY);
         if (fd == -1) {
-            sprintf(err_msg, "failed to open %s, %s", mount->dirname,
-                    strerror(errno));
-            error_set(err, QERR_QGA_COMMAND_FAILED, err_msg);
+            error_setg_errno(err, errno, "failed to open %s", mount->dirname);
             goto error;
         }
 
@@ -599,9 +596,8 @@ void qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **err)
         ret = ioctl(fd, FITRIM, &r);
         if (ret == -1) {
             if (errno != ENOTTY && errno != EOPNOTSUPP) {
-                sprintf(err_msg, "failed to trim %s, %s",
-                        mount->dirname, strerror(errno));
-                error_set(err, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(err, errno, "failed to trim %s",
+                                 mount->dirname);
                 close(fd);
                 goto error;
             }
-- 
1.7.9.5

[Qemu-devel] [PATCH 08/12] qemu-ga: qmp_guest_network_get_interfaces(): get rid of snprintf() + error_set()

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Convert them to error_setg_errno().

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   29 ++++++++---------------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index fa786e5..9b6ef17 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -802,12 +802,9 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
 {
     GuestNetworkInterfaceList *head = NULL, *cur_item = NULL;
     struct ifaddrs *ifap, *ifa;
-    char err_msg[512];
 
     if (getifaddrs(&ifap) < 0) {
-        snprintf(err_msg, sizeof(err_msg),
-                 "getifaddrs failed: %s", strerror(errno));
-        error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+        error_setg_errno(errp, errno, "getifaddrs failed");
         goto error;
     }
 
@@ -843,20 +840,16 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
             /* we haven't obtained HW address yet */
             sock = socket(PF_INET, SOCK_STREAM, 0);
             if (sock == -1) {
-                snprintf(err_msg, sizeof(err_msg),
-                         "failed to create socket: %s", strerror(errno));
-                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(errp, errno, "failed to create socket");
                 goto error;
             }
 
             memset(&ifr, 0, sizeof(ifr));
             pstrcpy(ifr.ifr_name, IF_NAMESIZE, info->value->name);
             if (ioctl(sock, SIOCGIFHWADDR, &ifr) == -1) {
-                snprintf(err_msg, sizeof(err_msg),
-                         "failed to get MAC address of %s: %s",
-                         ifa->ifa_name,
-                         strerror(errno));
-                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(errp, errno,
+                                 "failed to get MAC address of %s",
+                                 ifa->ifa_name);
                 goto error;
             }
 
@@ -867,9 +860,7 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
                          (int) mac_addr[0], (int) mac_addr[1],
                          (int) mac_addr[2], (int) mac_addr[3],
                          (int) mac_addr[4], (int) mac_addr[5]) == -1) {
-                snprintf(err_msg, sizeof(err_msg),
-                         "failed to format MAC: %s", strerror(errno));
-                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(errp, errno, "failed to format MAC");
                 goto error;
             }
 
@@ -884,9 +875,7 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
             address_item->value = g_malloc0(sizeof(*address_item->value));
             p = &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
             if (!inet_ntop(AF_INET, p, addr4, sizeof(addr4))) {
-                snprintf(err_msg, sizeof(err_msg),
-                         "inet_ntop failed : %s", strerror(errno));
-                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(errp, errno, "inet_ntop failed");
                 goto error;
             }
 
@@ -906,9 +895,7 @@ GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
             address_item->value = g_malloc0(sizeof(*address_item->value));
             p = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
             if (!inet_ntop(AF_INET6, p, addr6, sizeof(addr6))) {
-                snprintf(err_msg, sizeof(err_msg),
-                         "inet_ntop failed : %s", strerror(errno));
-                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
+                error_setg_errno(errp, errno, "inet_ntop failed");
                 goto error;
             }
 
-- 
1.7.9.5

[Qemu-devel] [PATCH 09/12] qemu-ga: bios_supports_mode(): improve error reporting

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Most errors are QERR_UNDEFINED_ERROR today.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   46 +++++++++++++++++++++++++++-------------------
 1 file changed, 27 insertions(+), 19 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 9b6ef17..f3ee492 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -618,8 +618,9 @@ error:
 static void bios_supports_mode(const char *pmutils_bin, const char *pmutils_arg,
                                const char *sysfile_str, Error **err)
 {
+    Error *local_err = NULL;
     char *pmutils_path;
-    pid_t pid, rpid;
+    pid_t pid;
     int status;
 
     pmutils_path = g_find_program_in_path(pmutils_bin);
@@ -664,31 +665,38 @@ static void bios_supports_mode(const char *pmutils_bin, const char *pmutils_arg,
         }
 
         _exit(SUSPEND_NOT_SUPPORTED);
+    } else if (pid < 0) {
+        error_setg_errno(err, errno, "failed to create child process");
+        goto out;
     }
 
-    g_free(pmutils_path);
+    ga_wait_child(pid, &status, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
+        goto out;
+    }
 
-    if (pid < 0) {
-        goto undef_err;
+    if (!WIFEXITED(status)) {
+        error_setg(err, "child process has terminated abnormally");
+        goto out;
     }
 
-    do {
-        rpid = waitpid(pid, &status, 0);
-    } while (rpid == -1 && errno == EINTR);
-    if (rpid == pid && WIFEXITED(status)) {
-        switch (WEXITSTATUS(status)) {
-        case SUSPEND_SUPPORTED:
-            return;
-        case SUSPEND_NOT_SUPPORTED:
-            error_set(err, QERR_UNSUPPORTED);
-            return;
-        default:
-            goto undef_err;
-        }
+    switch (WEXITSTATUS(status)) {
+    case SUSPEND_SUPPORTED:
+        goto out;
+    case SUSPEND_NOT_SUPPORTED:
+        error_setg(err,
+                   "the requested suspend mode is not supported by the guest");
+        goto out;
+    default:
+        error_setg(err,
+                   "the helper program '%s' returned an unexpected exit status"
+                   " code (%d)", pmutils_path, WEXITSTATUS(status));
+        goto out;
     }
 
-undef_err:
-    error_set(err, QERR_UNDEFINED_ERROR);
+out:
+    g_free(pmutils_path);
 }
 
 static void guest_suspend(const char *pmutils_bin, const char *sysfile_str,
-- 
1.7.9.5

[Qemu-devel] [PATCH 10/12] qemu-ga: guest_suspend(): improve error reporting

[Michael Roth]

From: Luiz Capitulino <lcapitulino@redhat.com>

Most errors are QERR_UNDEFINED_ERROR today.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c |   29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index f3ee492..614a421 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -702,8 +702,9 @@ out:
 static void guest_suspend(const char *pmutils_bin, const char *sysfile_str,
                           Error **err)
 {
+    Error *local_err = NULL;
     char *pmutils_path;
-    pid_t rpid, pid;
+    pid_t pid;
     int status;
 
     pmutils_path = g_find_program_in_path(pmutils_bin);
@@ -741,23 +742,29 @@ static void guest_suspend(const char *pmutils_bin, const char *sysfile_str,
         }
 
         _exit(EXIT_SUCCESS);
+    } else if (pid < 0) {
+        error_setg_errno(err, errno, "failed to create child process");
+        goto out;
     }
 
-    g_free(pmutils_path);
+    ga_wait_child(pid, &status, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
+        goto out;
+    }
 
-    if (pid < 0) {
-        goto exit_err;
+    if (!WIFEXITED(status)) {
+        error_setg(err, "child process has terminated abnormally");
+        goto out;
     }
 
-    do {
-        rpid = waitpid(pid, &status, 0);
-    } while (rpid == -1 && errno == EINTR);
-    if (rpid == pid && WIFEXITED(status) && !WEXITSTATUS(status)) {
-        return;
+    if (WEXITSTATUS(status)) {
+        error_setg(err, "child process has failed to suspend");
+        goto out;
     }
 
-exit_err:
-    error_set(err, QERR_UNDEFINED_ERROR);
+out:
+    g_free(pmutils_path);
 }
 
 void qmp_guest_suspend_disk(Error **err)
-- 
1.7.9.5

[Qemu-devel] [PATCH 11/12] qemu-ga: execute hook to quiesce the guest on fsfreeze-freeze/thaw

[Michael Roth]

From: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>

To use the online disk snapshot for online-backup, application-level
consistency of the snapshot image is required. However, currently the
guest agent can provide only filesystem-level consistency, and the
snapshot may contain dirty data, for example, incomplete transactions.
This patch provides the opportunity to quiesce applications before
snapshot is taken.

If --fsfreeze-hook option is specified, the hook is executed with
"freeze" argument before the filesystem is frozen by fsfreeze-freeze
command. As for fsfreeze-thaw command, the hook is executed with "thaw"
argument after the filesystem is thawed.

This patch depends on patchset to improve error reporting by Luiz Capitulino:
  http://lists.gnu.org/archive/html/qemu-devel/2012-11/msg03016.html

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>

*clarified usage in help output

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands-posix.c   |   69 ++++++++++++++++++++++++++++++++++++++++++++++++
 qga/guest-agent-core.h |    1 +
 qga/main.c             |   48 ++++++++++++++++++++++++++++++++-
 3 files changed, 117 insertions(+), 1 deletion(-)

diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 614a421..77f6ee7 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -410,6 +410,66 @@ static void build_fs_mount_list(FsMountList *mounts, Error **err)
 
 #if defined(CONFIG_FSFREEZE)
 
+typedef enum {
+    FSFREEZE_HOOK_THAW = 0,
+    FSFREEZE_HOOK_FREEZE,
+} FsfreezeHookArg;
+
+const char *fsfreeze_hook_arg_string[] = {
+    "thaw",
+    "freeze",
+};
+
+static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **err)
+{
+    int status;
+    pid_t pid;
+    const char *hook;
+    const char *arg_str = fsfreeze_hook_arg_string[arg];
+    Error *local_err = NULL;
+
+    hook = ga_fsfreeze_hook(ga_state);
+    if (!hook) {
+        return;
+    }
+    if (access(hook, X_OK) != 0) {
+        error_setg_errno(err, errno, "can't access fsfreeze hook '%s'", hook);
+        return;
+    }
+
+    slog("executing fsfreeze hook with arg '%s'", arg_str);
+    pid = fork();
+    if (pid == 0) {
+        setsid();
+        reopen_fd_to_null(0);
+        reopen_fd_to_null(1);
+        reopen_fd_to_null(2);
+
+        execle(hook, hook, arg_str, NULL, environ);
+        _exit(EXIT_FAILURE);
+    } else if (pid < 0) {
+        error_setg_errno(err, errno, "failed to create child process");
+        return;
+    }
+
+    ga_wait_child(pid, &status, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
+        return;
+    }
+
+    if (!WIFEXITED(status)) {
+        error_setg(err, "fsfreeze hook has terminated abnormally");
+        return;
+    }
+
+    status = WEXITSTATUS(status);
+    if (status) {
+        error_setg(err, "fsfreeze hook has failed with status %d", status);
+        return;
+    }
+}
+
 /*
  * Return status of freeze/thaw
  */
@@ -436,6 +496,12 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
 
     slog("guest-fsfreeze called");
 
+    execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(err, local_err);
+        return -1;
+    }
+
     QTAILQ_INIT(&mounts);
     build_fs_mount_list(&mounts, &local_err);
     if (error_is_set(&local_err)) {
@@ -537,6 +603,9 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err)
 
     ga_unset_frozen(ga_state);
     free_fs_mount_list(&mounts);
+
+    execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, err);
+
     return i;
 }
 
diff --git a/qga/guest-agent-core.h b/qga/guest-agent-core.h
index 8934163..3354598 100644
--- a/qga/guest-agent-core.h
+++ b/qga/guest-agent-core.h
@@ -34,6 +34,7 @@ void ga_set_response_delimited(GAState *s);
 bool ga_is_frozen(GAState *s);
 void ga_set_frozen(GAState *s);
 void ga_unset_frozen(GAState *s);
+const char *ga_fsfreeze_hook(GAState *s);
 
 #ifndef _WIN32
 void reopen_fd_to_null(int fd);
diff --git a/qga/main.c b/qga/main.c
index ba5fa1c..a9b968c 100644
--- a/qga/main.c
+++ b/qga/main.c
@@ -34,6 +34,12 @@
 #include "qga/service-win32.h"
 #include <windows.h>
 #endif
+#ifdef __linux__
+#include <linux/fs.h>
+#ifdef FIFREEZE
+#define CONFIG_FSFREEZE
+#endif
+#endif
 
 #ifndef _WIN32
 #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
@@ -42,6 +48,9 @@
 #endif
 #define QGA_STATEDIR_DEFAULT CONFIG_QEMU_LOCALSTATEDIR "/run"
 #define QGA_PIDFILE_DEFAULT QGA_STATEDIR_DEFAULT "/qemu-ga.pid"
+#ifdef CONFIG_FSFREEZE
+#define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
+#endif
 #define QGA_SENTINEL_BYTE 0xFF
 
 struct GAState {
@@ -64,6 +73,9 @@ struct GAState {
         const char *log_filepath;
         const char *pid_filepath;
     } deferred_options;
+#ifdef CONFIG_FSFREEZE
+    const char *fsfreeze_hook;
+#endif
 };
 
 struct GAState *ga_state;
@@ -153,6 +165,16 @@ static void usage(const char *cmd)
 "                    %s)\n"
 "  -l, --logfile     set logfile path, logs to stderr by default\n"
 "  -f, --pidfile     specify pidfile (default is %s)\n"
+#ifdef CONFIG_FSFREEZE
+"  -F, --fsfreeze-hook\n"
+"                    enable fsfreeze hook. Accepts an optional argument that\n"
+"                    specifies script to run on freeze/thaw. Script will be\n"
+"                    called with 'freeze'/'thaw' arguments accordingly.\n"
+"                    (default is %s)\n"
+"                    If using -F with an argument, do not follow -F with a\n"
+"                    space.\n"
+"                    (for example: -F/var/run/fsfreezehook.sh)\n"
+#endif
 "  -t, --statedir    specify dir to store state information (absolute paths\n"
 "                    only, default is %s)\n"
 "  -v, --verbose     log extra debugging information\n"
@@ -167,6 +189,9 @@ static void usage(const char *cmd)
 "\n"
 "Report bugs to <mdroth@linux.vnet.ibm.com>\n"
     , cmd, QEMU_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT,
+#ifdef CONFIG_FSFREEZE
+    QGA_FSFREEZE_HOOK_DEFAULT,
+#endif
     QGA_STATEDIR_DEFAULT);
 }
 
@@ -401,6 +426,13 @@ void ga_unset_frozen(GAState *s)
     }
 }
 
+#ifdef CONFIG_FSFREEZE
+const char *ga_fsfreeze_hook(GAState *s)
+{
+    return s->fsfreeze_hook;
+}
+#endif
+
 static void become_daemon(const char *pidfile)
 {
 #ifndef _WIN32
@@ -678,10 +710,13 @@ VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
 
 int main(int argc, char **argv)
 {
-    const char *sopt = "hVvdm:p:l:f:b:s:t:";
+    const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
     const char *method = NULL, *path = NULL;
     const char *log_filepath = NULL;
     const char *pid_filepath = QGA_PIDFILE_DEFAULT;
+#ifdef CONFIG_FSFREEZE
+    const char *fsfreeze_hook = NULL;
+#endif
     const char *state_dir = QGA_STATEDIR_DEFAULT;
 #ifdef _WIN32
     const char *service = NULL;
@@ -691,6 +726,9 @@ int main(int argc, char **argv)
         { "version", 0, NULL, 'V' },
         { "logfile", 1, NULL, 'l' },
         { "pidfile", 1, NULL, 'f' },
+#ifdef CONFIG_FSFREEZE
+        { "fsfreeze-hook", 2, NULL, 'F' },
+#endif
         { "verbose", 0, NULL, 'v' },
         { "method", 1, NULL, 'm' },
         { "path", 1, NULL, 'p' },
@@ -723,6 +761,11 @@ int main(int argc, char **argv)
         case 'f':
             pid_filepath = optarg;
             break;
+#ifdef CONFIG_FSFREEZE
+        case 'F':
+            fsfreeze_hook = optarg ? optarg : QGA_FSFREEZE_HOOK_DEFAULT;
+            break;
+#endif
         case 't':
              state_dir = optarg;
              break;
@@ -786,6 +829,9 @@ int main(int argc, char **argv)
     s = g_malloc0(sizeof(GAState));
     s->log_level = log_level;
     s->log_file = stderr;
+#ifdef CONFIG_FSFREEZE
+    s->fsfreeze_hook = fsfreeze_hook;
+#endif
     g_log_set_default_handler(ga_log, s);
     g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
     ga_enable_logging(s);
-- 
1.7.9.5

[Qemu-devel] [PATCH 12/12] qemu-ga: sample fsfreeze hooks

[Michael Roth]

From: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>

Adds sample hook scripts for --fsfreeze-hook option of qemu-ga.
  - fsfreeze-hook : execute scripts in fsfreeze-hook.d/
  - fsfreeze-hook.d/mysql-flush.sh.sample : quiesce MySQL before snapshot

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 .gitignore                                         |    1 +
 Makefile                                           |    2 +-
 scripts/qemu-guest-agent/fsfreeze-hook             |   33 ++++++++++++
 .../fsfreeze-hook.d/mysql-flush.sh.sample          |   56 ++++++++++++++++++++
 4 files changed, 91 insertions(+), 1 deletion(-)
 create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook
 create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample

diff --git a/.gitignore b/.gitignore
index 0e38169..5fea65d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -70,6 +70,7 @@ fsdev/virtfs-proxy-helper.pod
 *.tp
 *.vr
 *.d
+!scripts/qemu-guest-agent/fsfreeze-hook.d
 *.o
 *.lo
 *.la
diff --git a/Makefile b/Makefile
index a7ac04b..ee06448 100644
--- a/Makefile
+++ b/Makefile
@@ -232,7 +232,7 @@ clean:
 # avoid old build problems by removing potentially incorrect old files
 	rm -f config.mak op-i386.h opc-i386.h gen-op-i386.h op-arm.h opc-arm.h gen-op-arm.h
 	rm -f qemu-options.def
-	find . -name '*.[od]' -exec rm -f {} +
+	find . -name '*.[od]' -type f -exec rm -f {} +
 	rm -f *.a *.lo $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* *.pod *~ */*~
 	rm -Rf .libs
 	rm -f qemu-img-cmds.h
diff --git a/scripts/qemu-guest-agent/fsfreeze-hook b/scripts/qemu-guest-agent/fsfreeze-hook
new file mode 100755
index 0000000..c27b29f
--- /dev/null
+++ b/scripts/qemu-guest-agent/fsfreeze-hook
@@ -0,0 +1,33 @@
+#!/bin/sh
+
+# This script is executed when a guest agent receives fsfreeze-freeze and
+# fsfreeze-thaw command, if it is specified in --fsfreeze-hook (-F)
+# option of qemu-ga or placed in default path (/etc/qemu/fsfreeze-hook).
+# When the agent receives fsfreeze-freeze request, this script is issued with
+# "freeze" argument before the filesystem is frozen. And for fsfreeze-thaw
+# request, it is issued with "thaw" argument after filesystem is thawed.
+
+LOGFILE=/var/log/qga-fsfreeze-hook.log
+FSFREEZE_D=$(dirname -- "$0")/fsfreeze-hook.d
+
+# Check whether file $1 is a backup or rpm-generated file and should be ignored
+is_ignored_file() {
+    case "$1" in
+        *~ | *.bak | *.orig | *.rpmnew | *.rpmorig | *.rpmsave | *.sample)
+            return 0 ;;
+    esac
+    return 1
+}
+
+# Iterate executables in directory "fsfreeze-hook.d" with the specified args
+[ ! -d "$FSFREEZE_D" ] && exit 0
+for file in "$FSFREEZE_D"/* ; do
+    is_ignored_file "$file" && continue
+    [ -x "$file" ] || continue
+    printf "$(date): execute $file $@\n" >>$LOGFILE
+    "$file" "$@" >>$LOGFILE 2>&1
+    STATUS=$?
+    printf "$(date): $file finished with status=$STATUS\n" >>$LOGFILE
+done
+
+exit 0
diff --git a/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample
new file mode 100755
index 0000000..2b4fa3a
--- /dev/null
+++ b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample
@@ -0,0 +1,56 @@
+#!/bin/sh
+
+# Flush MySQL tables to the disk before the filesystem is frozen.
+# At the same time, this keeps a read lock in order to avoid write accesses
+# from the other clients until the filesystem is thawed.
+
+MYSQL="/usr/bin/mysql"
+MYSQL_OPTS="-uroot" #"-prootpassword"
+FIFO=/var/run/mysql-flush.fifo
+
+# Check mysql is installed and the server running
+[ -x "$MYSQL" ] && "$MYSQL" $MYSQL_OPTS < /dev/null || exit 0
+
+flush_and_wait() {
+    printf "FLUSH TABLES WITH READ LOCK \\G\n"
+    trap 'printf "$(date): $0 is killed\n">&2' HUP INT QUIT ALRM TERM
+    read < $FIFO
+    printf "UNLOCK TABLES \\G\n"
+    rm -f $FIFO
+}
+
+case "$1" in
+    freeze)
+        mkfifo $FIFO || exit 1
+        flush_and_wait | "$MYSQL" $MYSQL_OPTS &
+        # wait until every block is flushed
+        while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\
+                 "$MYSQL" $MYSQL_OPTS | tail -1 | cut -f 2)" -gt 0 ]; do
+            sleep 1
+        done
+        # for InnoDB, wait until every log is flushed
+        INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX)
+        [ $? -ne 0 ] && exit 2
+        trap "rm -f $INNODB_STATUS; exit 1" HUP INT QUIT ALRM TERM
+        while :; do
+            printf "SHOW ENGINE INNODB STATUS \\G" |\
+                "$MYSQL" $MYSQL_OPTS > $INNODB_STATUS
+            LOG_CURRENT=$(grep 'Log sequence number' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f4)
+            LOG_FLUSHED=$(grep 'Log flushed up to' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f5)
+            [ "$LOG_CURRENT" = "$LOG_FLUSHED" ] && break
+            sleep 1
+        done
+        rm -f $INNODB_STATUS
+        ;;
+
+    thaw)
+        [ ! -p $FIFO ] && exit 1
+        echo > $FIFO
+        ;;
+
+    *)
+        exit 1
+        ;;
+esac
-- 
1.7.9.5

Re: [Qemu-devel] [PULL 0/12] qemu-ga: error handling improvements and fsfreeze hooks

[Anthony Liguori]

Pulled, thanks.

Regards,

Anthony Liguori

Re: [Qemu-devel] [PATCH 11/12] qemu-ga: execute hook to quiesce the guest on fsfreeze-freeze/thaw

[Blue Swirl]

On Tue, Jan 8, 2013 at 11:00 PM, Michael Roth <mdroth@linux.vnet.ibm.com> wrote:
> From: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
>
> To use the online disk snapshot for online-backup, application-level
> consistency of the snapshot image is required. However, currently the
> guest agent can provide only filesystem-level consistency, and the
> snapshot may contain dirty data, for example, incomplete transactions.
> This patch provides the opportunity to quiesce applications before
> snapshot is taken.
>
> If --fsfreeze-hook option is specified, the hook is executed with
> "freeze" argument before the filesystem is frozen by fsfreeze-freeze
> command. As for fsfreeze-thaw command, the hook is executed with "thaw"
> argument after the filesystem is thawed.
>
> This patch depends on patchset to improve error reporting by Luiz Capitulino:
>   http://lists.gnu.org/archive/html/qemu-devel/2012-11/msg03016.html
>
> Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
>
> *clarified usage in help output
>
> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> ---
>  qga/commands-posix.c   |   69 ++++++++++++++++++++++++++++++++++++++++++++++++
>  qga/guest-agent-core.h |    1 +
>  qga/main.c             |   48 ++++++++++++++++++++++++++++++++-
>  3 files changed, 117 insertions(+), 1 deletion(-)
>
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 614a421..77f6ee7 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -410,6 +410,66 @@ static void build_fs_mount_list(FsMountList *mounts, Error **err)
>
>  #if defined(CONFIG_FSFREEZE)
>
> +typedef enum {
> +    FSFREEZE_HOOK_THAW = 0,
> +    FSFREEZE_HOOK_FREEZE,
> +} FsfreezeHookArg;
> +
> +const char *fsfreeze_hook_arg_string[] = {

static

> +    "thaw",
> +    "freeze",
> +};
> +
> +static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **err)
> +{
> +    int status;
> +    pid_t pid;
> +    const char *hook;
> +    const char *arg_str = fsfreeze_hook_arg_string[arg];
> +    Error *local_err = NULL;
> +
> +    hook = ga_fsfreeze_hook(ga_state);
> +    if (!hook) {
> +        return;
> +    }
> +    if (access(hook, X_OK) != 0) {
> +        error_setg_errno(err, errno, "can't access fsfreeze hook '%s'", hook);
> +        return;
> +    }
> +
> +    slog("executing fsfreeze hook with arg '%s'", arg_str);
> +    pid = fork();
> +    if (pid == 0) {
> +        setsid();
> +        reopen_fd_to_null(0);
> +        reopen_fd_to_null(1);
> +        reopen_fd_to_null(2);
> +
> +        execle(hook, hook, arg_str, NULL, environ);
> +        _exit(EXIT_FAILURE);
> +    } else if (pid < 0) {
> +        error_setg_errno(err, errno, "failed to create child process");
> +        return;
> +    }
> +
> +    ga_wait_child(pid, &status, &local_err);
> +    if (error_is_set(&local_err)) {
> +        error_propagate(err, local_err);
> +        return;
> +    }
> +
> +    if (!WIFEXITED(status)) {
> +        error_setg(err, "fsfreeze hook has terminated abnormally");
> +        return;
> +    }
> +
> +    status = WEXITSTATUS(status);
> +    if (status) {
> +        error_setg(err, "fsfreeze hook has failed with status %d", status);
> +        return;
> +    }
> +}
> +
>  /*
>   * Return status of freeze/thaw
>   */
> @@ -436,6 +496,12 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
>
>      slog("guest-fsfreeze called");
>
> +    execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err);
> +    if (error_is_set(&local_err)) {
> +        error_propagate(err, local_err);
> +        return -1;
> +    }
> +
>      QTAILQ_INIT(&mounts);
>      build_fs_mount_list(&mounts, &local_err);
>      if (error_is_set(&local_err)) {
> @@ -537,6 +603,9 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err)
>
>      ga_unset_frozen(ga_state);
>      free_fs_mount_list(&mounts);
> +
> +    execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, err);
> +
>      return i;
>  }
>
> diff --git a/qga/guest-agent-core.h b/qga/guest-agent-core.h
> index 8934163..3354598 100644
> --- a/qga/guest-agent-core.h
> +++ b/qga/guest-agent-core.h
> @@ -34,6 +34,7 @@ void ga_set_response_delimited(GAState *s);
>  bool ga_is_frozen(GAState *s);
>  void ga_set_frozen(GAState *s);
>  void ga_unset_frozen(GAState *s);
> +const char *ga_fsfreeze_hook(GAState *s);
>
>  #ifndef _WIN32
>  void reopen_fd_to_null(int fd);
> diff --git a/qga/main.c b/qga/main.c
> index ba5fa1c..a9b968c 100644
> --- a/qga/main.c
> +++ b/qga/main.c
> @@ -34,6 +34,12 @@
>  #include "qga/service-win32.h"
>  #include <windows.h>
>  #endif
> +#ifdef __linux__
> +#include <linux/fs.h>
> +#ifdef FIFREEZE
> +#define CONFIG_FSFREEZE
> +#endif
> +#endif
>
>  #ifndef _WIN32
>  #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
> @@ -42,6 +48,9 @@
>  #endif
>  #define QGA_STATEDIR_DEFAULT CONFIG_QEMU_LOCALSTATEDIR "/run"
>  #define QGA_PIDFILE_DEFAULT QGA_STATEDIR_DEFAULT "/qemu-ga.pid"
> +#ifdef CONFIG_FSFREEZE
> +#define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
> +#endif
>  #define QGA_SENTINEL_BYTE 0xFF
>
>  struct GAState {
> @@ -64,6 +73,9 @@ struct GAState {
>          const char *log_filepath;
>          const char *pid_filepath;
>      } deferred_options;
> +#ifdef CONFIG_FSFREEZE
> +    const char *fsfreeze_hook;
> +#endif
>  };
>
>  struct GAState *ga_state;
> @@ -153,6 +165,16 @@ static void usage(const char *cmd)
>  "                    %s)\n"
>  "  -l, --logfile     set logfile path, logs to stderr by default\n"
>  "  -f, --pidfile     specify pidfile (default is %s)\n"
> +#ifdef CONFIG_FSFREEZE
> +"  -F, --fsfreeze-hook\n"
> +"                    enable fsfreeze hook. Accepts an optional argument that\n"
> +"                    specifies script to run on freeze/thaw. Script will be\n"
> +"                    called with 'freeze'/'thaw' arguments accordingly.\n"
> +"                    (default is %s)\n"
> +"                    If using -F with an argument, do not follow -F with a\n"
> +"                    space.\n"
> +"                    (for example: -F/var/run/fsfreezehook.sh)\n"
> +#endif
>  "  -t, --statedir    specify dir to store state information (absolute paths\n"
>  "                    only, default is %s)\n"
>  "  -v, --verbose     log extra debugging information\n"
> @@ -167,6 +189,9 @@ static void usage(const char *cmd)
>  "\n"
>  "Report bugs to <mdroth@linux.vnet.ibm.com>\n"
>      , cmd, QEMU_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT,
> +#ifdef CONFIG_FSFREEZE
> +    QGA_FSFREEZE_HOOK_DEFAULT,
> +#endif
>      QGA_STATEDIR_DEFAULT);
>  }
>
> @@ -401,6 +426,13 @@ void ga_unset_frozen(GAState *s)
>      }
>  }
>
> +#ifdef CONFIG_FSFREEZE
> +const char *ga_fsfreeze_hook(GAState *s)
> +{
> +    return s->fsfreeze_hook;
> +}
> +#endif
> +
>  static void become_daemon(const char *pidfile)
>  {
>  #ifndef _WIN32
> @@ -678,10 +710,13 @@ VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
>
>  int main(int argc, char **argv)
>  {
> -    const char *sopt = "hVvdm:p:l:f:b:s:t:";
> +    const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
>      const char *method = NULL, *path = NULL;
>      const char *log_filepath = NULL;
>      const char *pid_filepath = QGA_PIDFILE_DEFAULT;
> +#ifdef CONFIG_FSFREEZE
> +    const char *fsfreeze_hook = NULL;
> +#endif
>      const char *state_dir = QGA_STATEDIR_DEFAULT;
>  #ifdef _WIN32
>      const char *service = NULL;
> @@ -691,6 +726,9 @@ int main(int argc, char **argv)
>          { "version", 0, NULL, 'V' },
>          { "logfile", 1, NULL, 'l' },
>          { "pidfile", 1, NULL, 'f' },
> +#ifdef CONFIG_FSFREEZE
> +        { "fsfreeze-hook", 2, NULL, 'F' },
> +#endif
>          { "verbose", 0, NULL, 'v' },
>          { "method", 1, NULL, 'm' },
>          { "path", 1, NULL, 'p' },
> @@ -723,6 +761,11 @@ int main(int argc, char **argv)
>          case 'f':
>              pid_filepath = optarg;
>              break;
> +#ifdef CONFIG_FSFREEZE
> +        case 'F':
> +            fsfreeze_hook = optarg ? optarg : QGA_FSFREEZE_HOOK_DEFAULT;
> +            break;
> +#endif
>          case 't':
>               state_dir = optarg;
>               break;
> @@ -786,6 +829,9 @@ int main(int argc, char **argv)
>      s = g_malloc0(sizeof(GAState));
>      s->log_level = log_level;
>      s->log_file = stderr;
> +#ifdef CONFIG_FSFREEZE
> +    s->fsfreeze_hook = fsfreeze_hook;
> +#endif
>      g_log_set_default_handler(ga_log, s);
>      g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
>      ga_enable_logging(s);
> --
> 1.7.9.5
>
>

Re: [Qemu-devel] [PATCH 11/12] qemu-ga: execute hook to quiesce the guest on fsfreeze-freeze/thaw

[Luiz Capitulino]

On Wed, 9 Jan 2013 21:02:37 +0000
Blue Swirl <blauwirbel@gmail.com> wrote:

> On Tue, Jan 8, 2013 at 11:00 PM, Michael Roth <mdroth@linux.vnet.ibm.com> wrote:
> > From: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
> >
> > To use the online disk snapshot for online-backup, application-level
> > consistency of the snapshot image is required. However, currently the
> > guest agent can provide only filesystem-level consistency, and the
> > snapshot may contain dirty data, for example, incomplete transactions.
> > This patch provides the opportunity to quiesce applications before
> > snapshot is taken.
> >
> > If --fsfreeze-hook option is specified, the hook is executed with
> > "freeze" argument before the filesystem is frozen by fsfreeze-freeze
> > command. As for fsfreeze-thaw command, the hook is executed with "thaw"
> > argument after the filesystem is thawed.
> >
> > This patch depends on patchset to improve error reporting by Luiz Capitulino:
> >   http://lists.gnu.org/archive/html/qemu-devel/2012-11/msg03016.html
> >
> > Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
> > Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
> >
> > *clarified usage in help output
> >
> > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> > ---
> >  qga/commands-posix.c   |   69 ++++++++++++++++++++++++++++++++++++++++++++++++
> >  qga/guest-agent-core.h |    1 +
> >  qga/main.c             |   48 ++++++++++++++++++++++++++++++++-
> >  3 files changed, 117 insertions(+), 1 deletion(-)
> >
> > diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> > index 614a421..77f6ee7 100644
> > --- a/qga/commands-posix.c
> > +++ b/qga/commands-posix.c
> > @@ -410,6 +410,66 @@ static void build_fs_mount_list(FsMountList *mounts, Error **err)
> >
> >  #if defined(CONFIG_FSFREEZE)
> >
> > +typedef enum {
> > +    FSFREEZE_HOOK_THAW = 0,
> > +    FSFREEZE_HOOK_FREEZE,
> > +} FsfreezeHookArg;
> > +
> > +const char *fsfreeze_hook_arg_string[] = {
> 
> static

This has already been merged. It's quite of a minor change anyway.

> 
> > +    "thaw",
> > +    "freeze",
> > +};
> > +
> > +static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **err)
> > +{
> > +    int status;
> > +    pid_t pid;
> > +    const char *hook;
> > +    const char *arg_str = fsfreeze_hook_arg_string[arg];
> > +    Error *local_err = NULL;
> > +
> > +    hook = ga_fsfreeze_hook(ga_state);
> > +    if (!hook) {
> > +        return;
> > +    }
> > +    if (access(hook, X_OK) != 0) {
> > +        error_setg_errno(err, errno, "can't access fsfreeze hook '%s'", hook);
> > +        return;
> > +    }
> > +
> > +    slog("executing fsfreeze hook with arg '%s'", arg_str);
> > +    pid = fork();
> > +    if (pid == 0) {
> > +        setsid();
> > +        reopen_fd_to_null(0);
> > +        reopen_fd_to_null(1);
> > +        reopen_fd_to_null(2);
> > +
> > +        execle(hook, hook, arg_str, NULL, environ);
> > +        _exit(EXIT_FAILURE);
> > +    } else if (pid < 0) {
> > +        error_setg_errno(err, errno, "failed to create child process");
> > +        return;
> > +    }
> > +
> > +    ga_wait_child(pid, &status, &local_err);
> > +    if (error_is_set(&local_err)) {
> > +        error_propagate(err, local_err);
> > +        return;
> > +    }
> > +
> > +    if (!WIFEXITED(status)) {
> > +        error_setg(err, "fsfreeze hook has terminated abnormally");
> > +        return;
> > +    }
> > +
> > +    status = WEXITSTATUS(status);
> > +    if (status) {
> > +        error_setg(err, "fsfreeze hook has failed with status %d", status);
> > +        return;
> > +    }
> > +}
> > +
> >  /*
> >   * Return status of freeze/thaw
> >   */
> > @@ -436,6 +496,12 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err)
> >
> >      slog("guest-fsfreeze called");
> >
> > +    execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err);
> > +    if (error_is_set(&local_err)) {
> > +        error_propagate(err, local_err);
> > +        return -1;
> > +    }
> > +
> >      QTAILQ_INIT(&mounts);
> >      build_fs_mount_list(&mounts, &local_err);
> >      if (error_is_set(&local_err)) {
> > @@ -537,6 +603,9 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err)
> >
> >      ga_unset_frozen(ga_state);
> >      free_fs_mount_list(&mounts);
> > +
> > +    execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, err);
> > +
> >      return i;
> >  }
> >
> > diff --git a/qga/guest-agent-core.h b/qga/guest-agent-core.h
> > index 8934163..3354598 100644
> > --- a/qga/guest-agent-core.h
> > +++ b/qga/guest-agent-core.h
> > @@ -34,6 +34,7 @@ void ga_set_response_delimited(GAState *s);
> >  bool ga_is_frozen(GAState *s);
> >  void ga_set_frozen(GAState *s);
> >  void ga_unset_frozen(GAState *s);
> > +const char *ga_fsfreeze_hook(GAState *s);
> >
> >  #ifndef _WIN32
> >  void reopen_fd_to_null(int fd);
> > diff --git a/qga/main.c b/qga/main.c
> > index ba5fa1c..a9b968c 100644
> > --- a/qga/main.c
> > +++ b/qga/main.c
> > @@ -34,6 +34,12 @@
> >  #include "qga/service-win32.h"
> >  #include <windows.h>
> >  #endif
> > +#ifdef __linux__
> > +#include <linux/fs.h>
> > +#ifdef FIFREEZE
> > +#define CONFIG_FSFREEZE
> > +#endif
> > +#endif
> >
> >  #ifndef _WIN32
> >  #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
> > @@ -42,6 +48,9 @@
> >  #endif
> >  #define QGA_STATEDIR_DEFAULT CONFIG_QEMU_LOCALSTATEDIR "/run"
> >  #define QGA_PIDFILE_DEFAULT QGA_STATEDIR_DEFAULT "/qemu-ga.pid"
> > +#ifdef CONFIG_FSFREEZE
> > +#define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
> > +#endif
> >  #define QGA_SENTINEL_BYTE 0xFF
> >
> >  struct GAState {
> > @@ -64,6 +73,9 @@ struct GAState {
> >          const char *log_filepath;
> >          const char *pid_filepath;
> >      } deferred_options;
> > +#ifdef CONFIG_FSFREEZE
> > +    const char *fsfreeze_hook;
> > +#endif
> >  };
> >
> >  struct GAState *ga_state;
> > @@ -153,6 +165,16 @@ static void usage(const char *cmd)
> >  "                    %s)\n"
> >  "  -l, --logfile     set logfile path, logs to stderr by default\n"
> >  "  -f, --pidfile     specify pidfile (default is %s)\n"
> > +#ifdef CONFIG_FSFREEZE
> > +"  -F, --fsfreeze-hook\n"
> > +"                    enable fsfreeze hook. Accepts an optional argument that\n"
> > +"                    specifies script to run on freeze/thaw. Script will be\n"
> > +"                    called with 'freeze'/'thaw' arguments accordingly.\n"
> > +"                    (default is %s)\n"
> > +"                    If using -F with an argument, do not follow -F with a\n"
> > +"                    space.\n"
> > +"                    (for example: -F/var/run/fsfreezehook.sh)\n"
> > +#endif
> >  "  -t, --statedir    specify dir to store state information (absolute paths\n"
> >  "                    only, default is %s)\n"
> >  "  -v, --verbose     log extra debugging information\n"
> > @@ -167,6 +189,9 @@ static void usage(const char *cmd)
> >  "\n"
> >  "Report bugs to <mdroth@linux.vnet.ibm.com>\n"
> >      , cmd, QEMU_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT,
> > +#ifdef CONFIG_FSFREEZE
> > +    QGA_FSFREEZE_HOOK_DEFAULT,
> > +#endif
> >      QGA_STATEDIR_DEFAULT);
> >  }
> >
> > @@ -401,6 +426,13 @@ void ga_unset_frozen(GAState *s)
> >      }
> >  }
> >
> > +#ifdef CONFIG_FSFREEZE
> > +const char *ga_fsfreeze_hook(GAState *s)
> > +{
> > +    return s->fsfreeze_hook;
> > +}
> > +#endif
> > +
> >  static void become_daemon(const char *pidfile)
> >  {
> >  #ifndef _WIN32
> > @@ -678,10 +710,13 @@ VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
> >
> >  int main(int argc, char **argv)
> >  {
> > -    const char *sopt = "hVvdm:p:l:f:b:s:t:";
> > +    const char *sopt = "hVvdm:p:l:f:F::b:s:t:";
> >      const char *method = NULL, *path = NULL;
> >      const char *log_filepath = NULL;
> >      const char *pid_filepath = QGA_PIDFILE_DEFAULT;
> > +#ifdef CONFIG_FSFREEZE
> > +    const char *fsfreeze_hook = NULL;
> > +#endif
> >      const char *state_dir = QGA_STATEDIR_DEFAULT;
> >  #ifdef _WIN32
> >      const char *service = NULL;
> > @@ -691,6 +726,9 @@ int main(int argc, char **argv)
> >          { "version", 0, NULL, 'V' },
> >          { "logfile", 1, NULL, 'l' },
> >          { "pidfile", 1, NULL, 'f' },
> > +#ifdef CONFIG_FSFREEZE
> > +        { "fsfreeze-hook", 2, NULL, 'F' },
> > +#endif
> >          { "verbose", 0, NULL, 'v' },
> >          { "method", 1, NULL, 'm' },
> >          { "path", 1, NULL, 'p' },
> > @@ -723,6 +761,11 @@ int main(int argc, char **argv)
> >          case 'f':
> >              pid_filepath = optarg;
> >              break;
> > +#ifdef CONFIG_FSFREEZE
> > +        case 'F':
> > +            fsfreeze_hook = optarg ? optarg : QGA_FSFREEZE_HOOK_DEFAULT;
> > +            break;
> > +#endif
> >          case 't':
> >               state_dir = optarg;
> >               break;
> > @@ -786,6 +829,9 @@ int main(int argc, char **argv)
> >      s = g_malloc0(sizeof(GAState));
> >      s->log_level = log_level;
> >      s->log_file = stderr;
> > +#ifdef CONFIG_FSFREEZE
> > +    s->fsfreeze_hook = fsfreeze_hook;
> > +#endif
> >      g_log_set_default_handler(ga_log, s);
> >      g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
> >      ga_enable_logging(s);
> > --
> > 1.7.9.5
> >
> >
>