From 64313464e1984166ed62446cb7a1e86a2e5fa053 Mon Sep 17 00:00:00 2001 From: Michael Roth Date: Mon, 5 Mar 2012 17:44:05 -0500 Subject: [PATCH 38/98] guest agent: add guest agent RPCs/commands This adds the initial set of QMP/QAPI commands provided by the guest agent: guest-sync guest-ping guest-info guest-shutdown guest-file-open guest-file-read guest-file-write guest-file-seek guest-file-flush guest-file-close guest-fsfreeze-freeze guest-fsfreeze-thaw guest-fsfreeze-status The input/output specification for these commands are documented in the schema. Example usage: host: qemu -device virtio-serial \ -chardev socket,path=/tmp/vs0.sock,server,nowait,id=qga0 \ -device virtserialport,chardev=qga0,name=org.qemu.quest_agent.0 ... echo "{'execute':'guest-info'}" | socat stdio unix-connect:/tmp/qga0.sock guest: qemu-ga -m virtio-serial -p /dev/virtio-ports/org.qemu.guest_agent.0 \ -p /var/run/qemu-guest-agent.pid -d Signed-off-by: Michael Roth Signed-off-by: Luiz Capitulino (cherry picked from commit e3d4d25206a13ca48936e4357a53591997ce6d57) BZ 632771 Deviations from upstream: - Resolved Makefile conflicts - Minor addition of a '{' required in qerror.c to match up correctly Signed-off-by: Jeff Cody Signed-off-by: Michal Novotny --- Makefile | 16 +- qapi-schema-guest.json | 217 ++++++++++++++++++ qemu-ga.c | 4 + qerror.c | 8 + qerror.h | 6 + qga/guest-agent-commands.c | 518 ++++++++++++++++++++++++++++++++++++++++++++ qga/guest-agent-core.h | 2 + 7 files changed, 768 insertions(+), 3 deletions(-) create mode 100644 qapi-schema-guest.json create mode 100644 qga/guest-agent-commands.c diff --git a/Makefile b/Makefile index f9e2237..6631c12 100644 --- a/Makefile +++ b/Makefile @@ -189,7 +189,7 @@ check-qjson: check-qjson.o qfloat.o qint.o qdict.o qstring.o qlist.o qbool.o qjs $(qapi-obj-y): $(GENERATED_HEADERS) qapi-dir := qapi-generated -test-visitor.o test-qmp-commands.o: QEMU_CFLAGS += -I $(qapi-dir) +test-visitor.o test-qmp-commands.o qemu-ga$(EXESUF): QEMU_CFLAGS += -I $(qapi-dir) $(qapi-dir)/test-qapi-types.c: $(qapi-dir)/test-qapi-types.h $(qapi-dir)/test-qapi-types.h: $(SRC_PATH)/qapi-schema-test.json $(SRC_PATH)/scripts/qapi-types.py @@ -201,17 +201,27 @@ $(qapi-dir)/test-qmp-commands.h: $(qapi-dir)/test-qmp-marshal.c $(qapi-dir)/test-qmp-marshal.c: $(SRC_PATH)/qapi-schema-test.json $(SRC_PATH)/scripts/qapi-commands.py $(call quiet-command,python $(SRC_PATH)/scripts/qapi-commands.py -o "$(qapi-dir)" -p "test-" < $<, " GEN $@") +$(qapi-dir)/qga-qapi-types.c: $(qapi-dir)/qga-qapi-types.h +$(qapi-dir)/qga-qapi-types.h: $(SRC_PATH)/qapi-schema-guest.json $(SRC_PATH)/scripts/qapi-types.py + $(call quiet-command,python $(SRC_PATH)/scripts/qapi-types.py -o "$(qapi-dir)" -p "qga-" < $<, " GEN $@") +$(qapi-dir)/qga-qapi-visit.c: $(qapi-dir)/qga-qapi-visit.h +$(qapi-dir)/qga-qapi-visit.h: $(SRC_PATH)/qapi-schema-guest.json $(SRC_PATH)/scripts/qapi-visit.py + $(call quiet-command,python $(SRC_PATH)/scripts/qapi-visit.py -o "$(qapi-dir)" -p "qga-" < $<, " GEN $@") +$(qapi-dir)/qga-qmp-marshal.c: $(SRC_PATH)/qapi-schema-guest.json $(SRC_PATH)/scripts/qapi-commands.py + $(call quiet-command,python $(SRC_PATH)/scripts/qapi-commands.py -o "$(qapi-dir)" -p "qga-" < $<, " GEN $@") + test-visitor.o: $(addprefix $(qapi-dir)/, test-qapi-types.c test-qapi-types.h test-qapi-visit.c test-qapi-visit.h) $(qapi-obj-y) test-visitor: test-visitor.o qfloat.o qint.o qdict.o qstring.o qlist.o qbool.o $(qapi-obj-y) error.o osdep.o qemu-malloc.o $(oslib-obj-y) qjson.o json-streamer.o json-lexer.o json-parser.o qerror.o qemu-error.o qemu-tool.o $(qapi-dir)/test-qapi-visit.o $(qapi-dir)/test-qapi-types.o test-qmp-commands.o: $(addprefix $(qapi-dir)/, test-qapi-types.c test-qapi-types.h test-qapi-visit.c test-qapi-visit.h test-qmp-marshal.c test-qmp-commands.h) $(qapi-obj-y) test-qmp-commands: test-qmp-commands.o qfloat.o qint.o qdict.o qstring.o qlist.o qbool.o $(qapi-obj-y) error.o osdep.o qemu-malloc.o $(oslib-obj-y) qjson.o json-streamer.o json-lexer.o json-parser.o qerror.o qemu-error.o qemu-tool.o $(qapi-dir)/test-qapi-visit.o $(qapi-dir)/test-qapi-types.o $(qapi-dir)/test-qmp-marshal.o module.o -QGALIB=qga/guest-agent-command-state.o +QGALIB=qga/guest-agent-command-state.o qga/guest-agent-commands.o qemu-ga.o: $(GENERATED_HEADERS) -qemu-ga$(EXESUF): qemu-ga.o $(QGALIB) qemu-tool.o qemu-error.o error.o $(oslib-obj-y) $(trace-obj-y) $(block-obj-y) $(qobject-obj-y) $(version-obj-y) $(qapi-obj-y) qemu-sockets.o module.o qapi/qmp-dispatch.o qapi/qmp-registry.o +qemu-ga.o: $(addprefix $(qapi-dir)/, qga-qapi-types.c qga-qapi-types.h qga-qapi-visit.c qga-qmp-marshal.c) $(qapi-obj-y) +qemu-ga$(EXESUF): qemu-ga.o $(QGALIB) qemu-tool.o qemu-error.o error.o $(oslib-obj-y) $(trace-obj-y) $(block-obj-y) $(qobject-obj-y) $(version-obj-y) $(qapi-obj-y) qemu-sockets.o module.o qapi/qmp-dispatch.o qapi/qmp-registry.o $(qapi-dir)/qga-qapi-visit.o $(qapi-dir)/qga-qapi-types.o $(qapi-dir)/qga-qmp-marshal.o QEMULIBS=libhw32 libhw64 libuser diff --git a/qapi-schema-guest.json b/qapi-schema-guest.json new file mode 100644 index 0000000..fde5971 --- /dev/null +++ b/qapi-schema-guest.json @@ -0,0 +1,217 @@ +# *-*- Mode: Python -*-* + +## +# @guest-sync: +# +# Echo back a unique integer value +# +# This is used by clients talking to the guest agent over the +# wire to ensure the stream is in sync and doesn't contain stale +# data from previous client. All guest agent responses should be +# ignored until the provided unique integer value is returned, +# and it is up to the client to handle stale whole or +# partially-delivered JSON text in such a way that this response +# can be obtained. +# +# Such clients should also preceed this command +# with a 0xFF byte to make such the guest agent flushes any +# partially read JSON data from a previous session. +# +# @id: randomly generated 64-bit integer +# +# Returns: The unique integer id passed in by the client +# +# Since: 0.15.0 +## +{ 'command': 'guest-sync' + 'data': { 'id': 'int' }, + 'returns': 'int' } + +## +# @guest-ping: +# +# Ping the guest agent, a non-error return implies success +# +# Since: 0.15.0 +## +{ 'command': 'guest-ping' } + +## +# @guest-info: +# +# Get some information about the guest agent. +# +# Since: 0.15.0 +## +{ 'type': 'GuestAgentInfo', 'data': {'version': 'str'} } +{ 'command': 'guest-info', + 'returns': 'GuestAgentInfo' } + +## +# @guest-shutdown: +# +# Initiate guest-activated shutdown. Note: this is an asynchronous +# shutdown request, with no guaruntee of successful shutdown. Errors +# will be logged to guest's syslog. +# +# @mode: #optional "halt", "powerdown" (default), or "reboot" +# +# Returns: Nothing on success +# +# Since: 0.15.0 +## +{ 'command': 'guest-shutdown', 'data': { '*mode': 'str' } } + +## +# @guest-file-open: +# +# Open a file in the guest and retrieve a file handle for it +# +# @filepath: Full path to the file in the guest to open. +# +# @mode: #optional open mode, as per fopen(), "r" is the default. +# +# Returns: Guest file handle on success. +# +# Since: 0.15.0 +## +{ 'command': 'guest-file-open', + 'data': { 'path': 'str', '*mode': 'str' }, + 'returns': 'int' } + +## +# @guest-file-close: +# +# Close an open file in the guest +# +# @handle: filehandle returned by guest-file-open +# +# Returns: Nothing on success. +# +# Since: 0.15.0 +## +{ 'command': 'guest-file-close', + 'data': { 'handle': 'int' } } + +## +# @guest-file-read: +# +# Read from an open file in the guest. Data will be base64-encoded +# +# @handle: filehandle returned by guest-file-open +# +# @count: #optional maximum number of bytes to read (default is 4KB) +# +# Returns: GuestFileRead on success. Note: count is number of bytes read +# *before* base64 encoding bytes read. +# +# Since: 0.15.0 +## +{ 'type': 'GuestFileRead', + 'data': { 'count': 'int', 'buf-b64': 'str', 'eof': 'bool' } } + +{ 'command': 'guest-file-read', + 'data': { 'handle': 'int', '*count': 'int' }, + 'returns': 'GuestFileRead' } + +## +# @guest-file-write: +# +# Write to an open file in the guest. +# +# @handle: filehandle returned by guest-file-open +# +# @buf-b64: base64-encoded string representing data to be written +# +# @count: #optional bytes to write (actual bytes, after base64-decode), +# default is all content in buf-b64 buffer after base64 decoding +# +# Returns: GuestFileWrite on success. Note: count is the number of bytes +# base64-decoded bytes written +# +# Since: 0.15.0 +## +{ 'type': 'GuestFileWrite', + 'data': { 'count': 'int', 'eof': 'bool' } } +{ 'command': 'guest-file-write', + 'data': { 'handle': 'int', 'buf-b64': 'str', '*count': 'int' }, + 'returns': 'GuestFileWrite' } + +## +# @guest-file-seek: +# +# Seek to a position in the file, as with fseek(), and return the +# current file position afterward. Also encapsulates ftell()'s +# functionality, just Set offset=0, whence=SEEK_CUR. +# +# @handle: filehandle returned by guest-file-open +# +# @offset: bytes to skip over in the file stream +# +# @whence: SEEK_SET, SEEK_CUR, or SEEK_END, as with fseek() +# +# Returns: GuestFileSeek on success. +# +# Since: 0.15.0 +## +{ 'type': 'GuestFileSeek', + 'data': { 'position': 'int', 'eof': 'bool' } } + +{ 'command': 'guest-file-seek', + 'data': { 'handle': 'int', 'offset': 'int', 'whence': 'int' }, + 'returns': 'GuestFileSeek' } + +## +# @guest-file-flush: +# +# Write file changes bufferred in userspace to disk/kernel buffers +# +# @handle: filehandle returned by guest-file-open +# +# Returns: Nothing on success. +# +# Since: 0.15.0 +## +{ 'command': 'guest-file-flush', + 'data': { 'handle': 'int' } } + +## +# @guest-fsfreeze-status: +# +# Get guest fsfreeze state. error state indicates failure to thaw 1 or more +# previously frozen filesystems, or failure to open a previously cached +# filesytem (filesystem unmounted/directory changes, etc). +# +# Returns: GuestFsfreezeStatus ("thawed", "frozen", etc., as defined below) +# +# Since: 0.15.0 +## +{ 'enum': 'GuestFsfreezeStatus', + 'data': [ 'thawed', 'frozen', 'error' ] } +{ 'command': 'guest-fsfreeze-status', + 'returns': 'GuestFsfreezeStatus' } + +## +# @guest-fsfreeze-freeze: +# +# Sync and freeze all non-network guest filesystems +# +# Returns: Number of file systems frozen on success +# +# Since: 0.15.0 +## +{ 'command': 'guest-fsfreeze-freeze', + 'returns': 'int' } + +## +# @guest-fsfreeze-thaw: +# +# Unfreeze frozen guest fileystems +# +# Returns: Number of file systems thawed +# If error, -1 (unknown error) or -errno +# +# Since: 0.15.0 +## +{ 'command': 'guest-fsfreeze-thaw', + 'returns': 'int' } diff --git a/qemu-ga.c b/qemu-ga.c index 1f3585c..6e2f61f 100644 --- a/qemu-ga.c +++ b/qemu-ga.c @@ -636,6 +636,9 @@ int main(int argc, char **argv) g_log_set_default_handler(ga_log, s); g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR); s->logging_enabled = true; + s->command_state = ga_command_state_new(); + ga_command_state_init(s, s->command_state); + ga_command_state_init_all(s->command_state); ga_state = s; module_call_init(MODULE_INIT_QAPI); @@ -644,6 +647,7 @@ int main(int argc, char **argv) g_main_loop_run(ga_state->main_loop); + ga_command_state_cleanup_all(ga_state->command_state); unlink(pidfile); return 0; diff --git a/qerror.c b/qerror.c index e76f487..a95fc80 100644 --- a/qerror.c +++ b/qerror.c @@ -231,6 +231,14 @@ static const QErrorStringTable qerror_table[] = { .desc = "Could not start VNC server on %(target)", }, { + .error_fmt = QERR_QGA_LOGGING_FAILED, + .desc = "Guest agent failed to log non-optional log statement", + }, + { + .error_fmt = QERR_QGA_COMMAND_FAILED, + .desc = "Guest agent command failed, error was '%(message)'", + }, + { .error_fmt = QERR_STREAMING_ERROR, .desc = "An error occurred during streaming: %(msg)", }, diff --git a/qerror.h b/qerror.h index 46a40dd..0644895 100644 --- a/qerror.h +++ b/qerror.h @@ -195,4 +195,10 @@ QError *qobject_to_qerror(const QObject *obj); #define QERR_STREAMING_ERROR \ "{ 'class': 'StreamingError', 'data': { 'msg': %s } }" +#define QERR_QGA_LOGGING_FAILED \ + "{ 'class': 'QgaLoggingFailed', 'data': {} }" + +#define QERR_QGA_COMMAND_FAILED \ + "{ 'class': 'QgaCommandFailed', 'data': { 'message': %s } }" + #endif /* QERROR_H */ diff --git a/qga/guest-agent-commands.c b/qga/guest-agent-commands.c new file mode 100644 index 0000000..8c0d67e --- /dev/null +++ b/qga/guest-agent-commands.c @@ -0,0 +1,518 @@ +/* + * QEMU Guest Agent commands + * + * Copyright IBM Corp. 2011 + * + * Authors: + * Michael Roth + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include +#include +#include +#include +#include +#include "qga/guest-agent-core.h" +#include "qga-qmp-commands.h" +#include "qerror.h" +#include "qemu-queue.h" + +static GAState *ga_state; + +static void disable_logging(void) +{ + ga_disable_logging(ga_state); +} + +static void enable_logging(void) +{ + ga_enable_logging(ga_state); +} + +/* Note: in some situations, like with the fsfreeze, logging may be + * temporarilly disabled. if it is necessary that a command be able + * to log for accounting purposes, check ga_logging_enabled() beforehand, + * and use the QERR_QGA_LOGGING_DISABLED to generate an error + */ +static void slog(const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + g_logv("syslog", G_LOG_LEVEL_INFO, fmt, ap); + va_end(ap); +} + +int64_t qmp_guest_sync(int64_t id, Error **errp) +{ + return id; +} + +void qmp_guest_ping(Error **err) +{ + slog("guest-ping called"); +} + +struct GuestAgentInfo *qmp_guest_info(Error **err) +{ + GuestAgentInfo *info = qemu_mallocz(sizeof(GuestAgentInfo)); + + info->version = g_strdup(QGA_VERSION); + + return info; +} + +void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err) +{ + int ret; + const char *shutdown_flag; + + slog("guest-shutdown called, mode: %s", mode); + if (!has_mode || strcmp(mode, "powerdown") == 0) { + shutdown_flag = "-P"; + } else if (strcmp(mode, "halt") == 0) { + shutdown_flag = "-H"; + } else if (strcmp(mode, "reboot") == 0) { + shutdown_flag = "-r"; + } else { + error_set(err, QERR_INVALID_PARAMETER_VALUE, "mode", + "halt|powerdown|reboot"); + return; + } + + ret = fork(); + if (ret == 0) { + /* child, start the shutdown */ + setsid(); + fclose(stdin); + fclose(stdout); + fclose(stderr); + + ret = execl("/sbin/shutdown", "shutdown", shutdown_flag, "+0", + "hypervisor initiated shutdown", (char*)NULL); + if (ret) { + slog("guest-shutdown failed: %s", strerror(errno)); + } + exit(!!ret); + } else if (ret < 0) { + error_set(err, QERR_UNDEFINED_ERROR); + } +} + +typedef struct GuestFileHandle { + uint64_t id; + FILE *fh; + QTAILQ_ENTRY(GuestFileHandle) next; +} GuestFileHandle; + +static struct { + QTAILQ_HEAD(, GuestFileHandle) filehandles; +} guest_file_state; + +static void guest_file_handle_add(FILE *fh) +{ + GuestFileHandle *gfh; + + gfh = qemu_mallocz(sizeof(GuestFileHandle)); + gfh->id = fileno(fh); + gfh->fh = fh; + QTAILQ_INSERT_TAIL(&guest_file_state.filehandles, gfh, next); +} + +static GuestFileHandle *guest_file_handle_find(int64_t id) +{ + GuestFileHandle *gfh; + + QTAILQ_FOREACH(gfh, &guest_file_state.filehandles, next) + { + if (gfh->id == id) { + return gfh; + } + } + + return NULL; +} + +int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode, Error **err) +{ + FILE *fh; + int fd; + int64_t ret = -1; + + if (!has_mode) { + mode = "r"; + } + 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); + return -1; + } + + /* set fd non-blocking to avoid common use cases (like reading from a + * named pipe) from hanging the agent + */ + fd = fileno(fh); + 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"); + fclose(fh); + return -1; + } + + guest_file_handle_add(fh); + slog("guest-file-open, handle: %d", fd); + return fd; +} + +void qmp_guest_file_close(int64_t handle, Error **err) +{ + GuestFileHandle *gfh = guest_file_handle_find(handle); + int ret; + + slog("guest-file-close called, handle: %ld", handle); + if (!gfh) { + error_set(err, QERR_FD_NOT_FOUND, "handle"); + return; + } + + ret = fclose(gfh->fh); + if (ret == -1) { + error_set(err, QERR_QGA_COMMAND_FAILED, "fclose() failed"); + return; + } + + QTAILQ_REMOVE(&guest_file_state.filehandles, gfh, next); + qemu_free(gfh); +} + +struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count, + int64_t count, Error **err) +{ + GuestFileHandle *gfh = guest_file_handle_find(handle); + GuestFileRead *read_data = NULL; + guchar *buf; + FILE *fh; + size_t read_count; + + if (!gfh) { + error_set(err, QERR_FD_NOT_FOUND, "handle"); + return NULL; + } + + if (!has_count) { + count = QGA_READ_COUNT_DEFAULT; + } else if (count < 0) { + error_set(err, QERR_INVALID_PARAMETER, "count"); + return NULL; + } + + fh = gfh->fh; + buf = qemu_mallocz(count+1); + read_count = fread(buf, 1, count, fh); + if (ferror(fh)) { + slog("guest-file-read failed, handle: %ld", handle); + error_set(err, QERR_QGA_COMMAND_FAILED, "fread() failed"); + } else { + buf[read_count] = 0; + read_data = qemu_mallocz(sizeof(GuestFileRead)); + read_data->count = read_count; + read_data->eof = feof(fh); + if (read_count) { + read_data->buf_b64 = g_base64_encode(buf, read_count); + } + } + qemu_free(buf); + clearerr(fh); + + return read_data; +} + +GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64, + bool has_count, int64_t count, Error **err) +{ + GuestFileWrite *write_data = NULL; + guchar *buf; + gsize buf_len; + int write_count; + GuestFileHandle *gfh = guest_file_handle_find(handle); + FILE *fh; + + if (!gfh) { + error_set(err, QERR_FD_NOT_FOUND, "handle"); + return NULL; + } + + fh = gfh->fh; + buf = g_base64_decode(buf_b64, &buf_len); + + if (!has_count) { + count = buf_len; + } else if (count < 0 || count > buf_len) { + qemu_free(buf); + error_set(err, QERR_INVALID_PARAMETER, "count"); + return NULL; + } + + write_count = fwrite(buf, 1, count, fh); + if (ferror(fh)) { + slog("guest-file-write failed, handle: %ld", handle); + error_set(err, QERR_QGA_COMMAND_FAILED, "fwrite() error"); + } else { + write_data = qemu_mallocz(sizeof(GuestFileWrite)); + write_data->count = write_count; + write_data->eof = feof(fh); + } + qemu_free(buf); + clearerr(fh); + + return write_data; +} + +struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, + int64_t whence, Error **err) +{ + GuestFileHandle *gfh = guest_file_handle_find(handle); + GuestFileSeek *seek_data = NULL; + FILE *fh; + int ret; + + if (!gfh) { + error_set(err, QERR_FD_NOT_FOUND, "handle"); + return NULL; + } + + fh = gfh->fh; + ret = fseek(fh, offset, whence); + if (ret == -1) { + error_set(err, QERR_QGA_COMMAND_FAILED, strerror(errno)); + } else { + seek_data = qemu_mallocz(sizeof(GuestFileRead)); + seek_data->position = ftell(fh); + seek_data->eof = feof(fh); + } + clearerr(fh); + + return seek_data; +} + +void qmp_guest_file_flush(int64_t handle, Error **err) +{ + GuestFileHandle *gfh = guest_file_handle_find(handle); + FILE *fh; + int ret; + + if (!gfh) { + error_set(err, QERR_FD_NOT_FOUND, "handle"); + return; + } + + fh = gfh->fh; + ret = fflush(fh); + if (ret == EOF) { + error_set(err, QERR_QGA_COMMAND_FAILED, strerror(errno)); + } +} + +static void guest_file_init(void) +{ + QTAILQ_INIT(&guest_file_state.filehandles); +} + +typedef struct GuestFsfreezeMount { + char *dirname; + char *devtype; + QTAILQ_ENTRY(GuestFsfreezeMount) next; +} GuestFsfreezeMount; + +struct { + GuestFsfreezeStatus status; + QTAILQ_HEAD(, GuestFsfreezeMount) mount_list; +} guest_fsfreeze_state; + +/* + * Walk the mount table and build a list of local file systems + */ +static int guest_fsfreeze_build_mount_list(void) +{ + struct mntent *ment; + GuestFsfreezeMount *mount, *temp; + char const *mtab = MOUNTED; + FILE *fp; + + QTAILQ_FOREACH_SAFE(mount, &guest_fsfreeze_state.mount_list, next, temp) { + QTAILQ_REMOVE(&guest_fsfreeze_state.mount_list, mount, next); + qemu_free(mount->dirname); + qemu_free(mount->devtype); + qemu_free(mount); + } + + fp = setmntent(mtab, "r"); + if (!fp) { + g_warning("fsfreeze: unable to read mtab"); + return -1; + } + + while ((ment = getmntent(fp))) { + /* + * An entry which device name doesn't start with a '/' is + * either a dummy file system or a network file system. + * Add special handling for smbfs and cifs as is done by + * coreutils as well. + */ + if ((ment->mnt_fsname[0] != '/') || + (strcmp(ment->mnt_type, "smbfs") == 0) || + (strcmp(ment->mnt_type, "cifs") == 0)) { + continue; + } + + mount = qemu_mallocz(sizeof(GuestFsfreezeMount)); + mount->dirname = qemu_strdup(ment->mnt_dir); + mount->devtype = qemu_strdup(ment->mnt_type); + + QTAILQ_INSERT_TAIL(&guest_fsfreeze_state.mount_list, mount, next); + } + + endmntent(fp); + + return 0; +} + +/* + * Return status of freeze/thaw + */ +GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error **err) +{ + return guest_fsfreeze_state.status; +} + +/* + * Walk list of mounted file systems in the guest, and freeze the ones which + * are real local file systems. + */ +int64_t qmp_guest_fsfreeze_freeze(Error **err) +{ + int ret = 0, i = 0; + struct GuestFsfreezeMount *mount, *temp; + int fd; + char err_msg[512]; + + slog("guest-fsfreeze called"); + + if (guest_fsfreeze_state.status == GUEST_FSFREEZE_STATUS_FROZEN) { + return 0; + } + + ret = guest_fsfreeze_build_mount_list(); + if (ret < 0) { + return ret; + } + + /* cannot risk guest agent blocking itself on a write in this state */ + disable_logging(); + + QTAILQ_FOREACH_SAFE(mount, &guest_fsfreeze_state.mount_list, next, temp) { + 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); + goto error; + } + + /* we try to cull filesytems we know won't work in advance, but other + * filesytems may not implement fsfreeze for less obvious reasons. + * these will report EOPNOTSUPP, so we simply ignore them. when + * thawing, these filesystems will return an EINVAL instead, due to + * not being in a frozen state. Other filesystem-specific + * errors may result in EINVAL, however, so the user should check the + * number * of filesystems returned here against those returned by the + * thaw operation to determine whether everything completed + * successfully + */ + ret = ioctl(fd, FIFREEZE); + if (ret < 0 && errno != EOPNOTSUPP) { + sprintf(err_msg, "failed to freeze %s, %s", mount->dirname, strerror(errno)); + error_set(err, QERR_QGA_COMMAND_FAILED, err_msg); + close(fd); + goto error; + } + close(fd); + + i++; + } + + guest_fsfreeze_state.status = GUEST_FSFREEZE_STATUS_FROZEN; + return i; + +error: + if (i > 0) { + qmp_guest_fsfreeze_thaw(NULL); + } + return 0; +} + +/* + * Walk list of frozen file systems in the guest, and thaw them. + */ +int64_t qmp_guest_fsfreeze_thaw(Error **err) +{ + int ret; + GuestFsfreezeMount *mount, *temp; + int fd, i = 0; + bool has_error = false; + + QTAILQ_FOREACH_SAFE(mount, &guest_fsfreeze_state.mount_list, next, temp) { + fd = qemu_open(mount->dirname, O_RDONLY); + if (fd == -1) { + has_error = true; + continue; + } + ret = ioctl(fd, FITHAW); + if (ret < 0 && errno != EOPNOTSUPP && errno != EINVAL) { + has_error = true; + close(fd); + continue; + } + close(fd); + i++; + } + + if (has_error) { + guest_fsfreeze_state.status = GUEST_FSFREEZE_STATUS_ERROR; + } else { + guest_fsfreeze_state.status = GUEST_FSFREEZE_STATUS_THAWED; + } + enable_logging(); + return i; +} + +static void guest_fsfreeze_init(void) +{ + guest_fsfreeze_state.status = GUEST_FSFREEZE_STATUS_THAWED; + QTAILQ_INIT(&guest_fsfreeze_state.mount_list); +} + +static void guest_fsfreeze_cleanup(void) +{ + int64_t ret; + Error *err = NULL; + + if (guest_fsfreeze_state.status == GUEST_FSFREEZE_STATUS_FROZEN) { + ret = qmp_guest_fsfreeze_thaw(&err); + if (ret < 0 || err) { + slog("failed to clean up frozen filesystems"); + } + } +} + +/* register init/cleanup routines for stateful command groups */ +void ga_command_state_init(GAState *s, GACommandState *cs) +{ + ga_state = s; + ga_command_state_add(cs, guest_fsfreeze_init, guest_fsfreeze_cleanup); + ga_command_state_add(cs, guest_file_init, NULL); +} diff --git a/qga/guest-agent-core.h b/qga/guest-agent-core.h index 66d1729..e42b91d 100644 --- a/qga/guest-agent-core.h +++ b/qga/guest-agent-core.h @@ -14,10 +14,12 @@ #include "qemu-common.h" #define QGA_VERSION "1.0" +#define QGA_READ_COUNT_DEFAULT 4 << 10 typedef struct GAState GAState; typedef struct GACommandState GACommandState; +void ga_command_state_init(GAState *s, GACommandState *cs); void ga_command_state_add(GACommandState *cs, void (*init)(void), void (*cleanup)(void)); -- 1.7.7.6