Message ID | 1444215574-11895-3-git-send-email-den@openvz.org |
---|---|
State | New |
Headers | show |
Quoting Denis V. Lunev (2015-10-07 05:59:34) > From: Olga Krishtal <okrishtal@virtuozzo.com> > > Set fd non-blocking to avoid common use cases (like reading from a > named pipe) from hanging the agent. This was missed in the original > code. > > Restore compatibility with Posix implementation. > > The patch adds Win32 specific implementation of qemu_set_nonblock. > > On Windows OS there is a separate API for changing flags of file, pipes > and sockets. Portable way to change file descriptor flags requires > to detect file descriptor type and proper actions depending of that > type. The patch adds wrapper qemu_set_fd_nonblocking into Windows specific > code to handle this stuff properly. > > The only problem is that qemu_set_nonblock is void but this should not > be a big deal. > > Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com> > Signed-off-by: Denis V. Lunev <den@openvz.org> > Reviewed-by: Yuri Pudgorodskiy <yur@virtuozzo.com> > CC: Michael Roth <mdroth@linux.vnet.ibm.com> > CC: Stefan Weil <sw@weilnetz.de> > --- > qga/commands-win32.c | 6 ++++++ > util/oslib-win32.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++----- > 2 files changed, 53 insertions(+), 5 deletions(-) > > diff --git a/qga/commands-win32.c b/qga/commands-win32.c > index 3374678..3274417 100644 > --- a/qga/commands-win32.c > +++ b/qga/commands-win32.c > @@ -34,6 +34,7 @@ > #include "qapi/qmp/qerror.h" > #include "qemu/queue.h" > #include "qemu/host-utils.h" > +#include "qemu/sockets.h" > > #ifndef SHTDN_REASON_FLAG_PLANNED > #define SHTDN_REASON_FLAG_PLANNED 0x80000000 > @@ -158,6 +159,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, > return -1; > } > > + /* set fd non-blocking to avoid common use cases (like reading from a > + * named pipe) from hanging the agent > + */ > + qemu_set_nonblock(fileno(fh)); > + > fd = guest_file_handle_add(fh, errp); > if (fd < 0) { > CloseHandle(&fh); > diff --git a/util/oslib-win32.c b/util/oslib-win32.c > index 08f5a9c..f19aed5 100644 > --- a/util/oslib-win32.c > +++ b/util/oslib-win32.c > @@ -121,17 +121,59 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) > } > #endif /* CONFIG_LOCALTIME_R */ > > -void qemu_set_block(int fd) > +static void qemu_set_fd_nonblocking(int fd, bool nonblocking) > { > - unsigned long opt = 0; > - WSAEventSelect(fd, NULL, 0); > + HANDLE handle; > + DWORD file_type, pipe_state; > + > + handle = (HANDLE)_get_osfhandle(fd); > + if (handle == INVALID_HANDLE_VALUE) { > + return; > + } > + > + file_type = GetFileType(handle); > + if (file_type != FILE_TYPE_PIPE) { > + return; > + } > + > + /* If file_type == FILE_TYPE_PIPE, according to msdn > + * the specified file is socket or named pipe */ > + if (GetNamedPipeHandleState(handle, &pipe_state, NULL, > + NULL, NULL, NULL, 0)) { > + /* The fd is named pipe fd */ > + if (!nonblocking == !(pipe_state & PIPE_NOWAIT)) { > + /* In this case we do not need perform any operation, because > + * nonblocking = true and PIPE_NOWAIT is already set or > + * nonblocking = false and PIPE_NOWAIT is not set */ > + return; > + } > + > + if (nonblocking) { > + pipe_state |= PIPE_NOWAIT; > + } else { > + pipe_state &= ~PIPE_NOWAIT; > + } > + > + SetNamedPipeHandleState(handle, &pipe_state, NULL, NULL); > + return; > + } > + > + /* The fd is socket fd */ > + unsigned long opt = (unsigned long)nonblocking; > + if (!nonblocking) { > + WSAEventSelect(fd, NULL, 0); > + } > ioctlsocket(fd, FIONBIO, &opt); > } > > +void qemu_set_block(int fd) > +{ > + qemu_set_fd_nonblocking(fd, false); > +} > + > void qemu_set_nonblock(int fd) > { > - unsigned long opt = 1; > - ioctlsocket(fd, FIONBIO, &opt); > + qemu_set_fd_nonblocking(fd, true); > qemu_fd_register(fd); This still potentially calls qemu_fd_register() on a non-socket FD as noted in prior review. I think the fix is trivial, but if you can change and re-test that would be ideal. Since guest-file* already supports reading/writing to w32 pipes I can pick this up during soft-freeze if it comes to that. Since we're still taking the approach of generalizing qemu_set_nonblock() for win32 I'd really prefer to get Stefan's Ack/Reviewed-by before applying. > } > > -- > 2.1.4 >
On 10/12/2015 08:38 PM, Michael Roth wrote: > Quoting Denis V. Lunev (2015-10-07 05:59:34) >> From: Olga Krishtal <okrishtal@virtuozzo.com> >> >> Set fd non-blocking to avoid common use cases (like reading from a >> named pipe) from hanging the agent. This was missed in the original >> code. >> >> Restore compatibility with Posix implementation. >> >> The patch adds Win32 specific implementation of qemu_set_nonblock. >> >> On Windows OS there is a separate API for changing flags of file, pipes >> and sockets. Portable way to change file descriptor flags requires >> to detect file descriptor type and proper actions depending of that >> type. The patch adds wrapper qemu_set_fd_nonblocking into Windows specific >> code to handle this stuff properly. >> >> The only problem is that qemu_set_nonblock is void but this should not >> be a big deal. >> >> Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com> >> Signed-off-by: Denis V. Lunev <den@openvz.org> >> Reviewed-by: Yuri Pudgorodskiy <yur@virtuozzo.com> >> CC: Michael Roth <mdroth@linux.vnet.ibm.com> >> CC: Stefan Weil <sw@weilnetz.de> >> --- >> qga/commands-win32.c | 6 ++++++ >> util/oslib-win32.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++----- >> 2 files changed, 53 insertions(+), 5 deletions(-) >> >> diff --git a/qga/commands-win32.c b/qga/commands-win32.c >> index 3374678..3274417 100644 >> --- a/qga/commands-win32.c >> +++ b/qga/commands-win32.c >> @@ -34,6 +34,7 @@ >> #include "qapi/qmp/qerror.h" >> #include "qemu/queue.h" >> #include "qemu/host-utils.h" >> +#include "qemu/sockets.h" >> >> #ifndef SHTDN_REASON_FLAG_PLANNED >> #define SHTDN_REASON_FLAG_PLANNED 0x80000000 >> @@ -158,6 +159,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, >> return -1; >> } >> >> + /* set fd non-blocking to avoid common use cases (like reading from a >> + * named pipe) from hanging the agent >> + */ >> + qemu_set_nonblock(fileno(fh)); >> + >> fd = guest_file_handle_add(fh, errp); >> if (fd < 0) { >> CloseHandle(&fh); >> diff --git a/util/oslib-win32.c b/util/oslib-win32.c >> index 08f5a9c..f19aed5 100644 >> --- a/util/oslib-win32.c >> +++ b/util/oslib-win32.c >> @@ -121,17 +121,59 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) >> } >> #endif /* CONFIG_LOCALTIME_R */ >> >> -void qemu_set_block(int fd) >> +static void qemu_set_fd_nonblocking(int fd, bool nonblocking) >> { >> - unsigned long opt = 0; >> - WSAEventSelect(fd, NULL, 0); >> + HANDLE handle; >> + DWORD file_type, pipe_state; >> + >> + handle = (HANDLE)_get_osfhandle(fd); >> + if (handle == INVALID_HANDLE_VALUE) { >> + return; >> + } >> + >> + file_type = GetFileType(handle); >> + if (file_type != FILE_TYPE_PIPE) { >> + return; >> + } >> + >> + /* If file_type == FILE_TYPE_PIPE, according to msdn >> + * the specified file is socket or named pipe */ >> + if (GetNamedPipeHandleState(handle, &pipe_state, NULL, >> + NULL, NULL, NULL, 0)) { >> + /* The fd is named pipe fd */ >> + if (!nonblocking == !(pipe_state & PIPE_NOWAIT)) { >> + /* In this case we do not need perform any operation, because >> + * nonblocking = true and PIPE_NOWAIT is already set or >> + * nonblocking = false and PIPE_NOWAIT is not set */ >> + return; >> + } >> + >> + if (nonblocking) { >> + pipe_state |= PIPE_NOWAIT; >> + } else { >> + pipe_state &= ~PIPE_NOWAIT; >> + } >> + >> + SetNamedPipeHandleState(handle, &pipe_state, NULL, NULL); >> + return; >> + } >> + >> + /* The fd is socket fd */ >> + unsigned long opt = (unsigned long)nonblocking; >> + if (!nonblocking) { >> + WSAEventSelect(fd, NULL, 0); >> + } >> ioctlsocket(fd, FIONBIO, &opt); >> } >> >> +void qemu_set_block(int fd) >> +{ >> + qemu_set_fd_nonblocking(fd, false); >> +} >> + >> void qemu_set_nonblock(int fd) >> { >> - unsigned long opt = 1; >> - ioctlsocket(fd, FIONBIO, &opt); >> + qemu_set_fd_nonblocking(fd, true); >> qemu_fd_register(fd); > This still potentially calls qemu_fd_register() on a non-socket FD as > noted in prior review. I think the fix is trivial, but if you can > change and re-test that would be ideal. > > Since guest-file* already supports reading/writing to w32 pipes I can > pick this up during soft-freeze if it comes to that. > > Since we're still taking the approach of generalizing > qemu_set_nonblock() for win32 I'd really prefer to get Stefan's > Ack/Reviewed-by before applying. you are perfectly correct, I have missed this fact from previous discussion. Sure this needs to be addressed. Thank you for a review. Den
Hi, please see my inline comments below. Am 12.10.2015 um 19:38 schrieb Michael Roth: > Quoting Denis V. Lunev (2015-10-07 05:59:34) >> From: Olga Krishtal <okrishtal@virtuozzo.com> >> >> Set fd non-blocking to avoid common use cases (like reading from a >> named pipe) from hanging the agent. This was missed in the original >> code. >> >> Restore compatibility with Posix implementation. >> >> The patch adds Win32 specific implementation of qemu_set_nonblock. >> >> On Windows OS there is a separate API for changing flags of file, pipes >> and sockets. Portable way to change file descriptor flags requires >> to detect file descriptor type and proper actions depending of that >> type. The patch adds wrapper qemu_set_fd_nonblocking into Windows specific >> code to handle this stuff properly. >> >> The only problem is that qemu_set_nonblock is void but this should not >> be a big deal. >> >> Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com> >> Signed-off-by: Denis V. Lunev <den@openvz.org> >> Reviewed-by: Yuri Pudgorodskiy <yur@virtuozzo.com> >> CC: Michael Roth <mdroth@linux.vnet.ibm.com> >> CC: Stefan Weil <sw@weilnetz.de> >> --- >> qga/commands-win32.c | 6 ++++++ >> util/oslib-win32.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++----- >> 2 files changed, 53 insertions(+), 5 deletions(-) >> >> diff --git a/qga/commands-win32.c b/qga/commands-win32.c >> index 3374678..3274417 100644 >> --- a/qga/commands-win32.c >> +++ b/qga/commands-win32.c >> @@ -34,6 +34,7 @@ >> #include "qapi/qmp/qerror.h" >> #include "qemu/queue.h" >> #include "qemu/host-utils.h" >> +#include "qemu/sockets.h" >> >> #ifndef SHTDN_REASON_FLAG_PLANNED >> #define SHTDN_REASON_FLAG_PLANNED 0x80000000 >> @@ -158,6 +159,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, >> return -1; >> } >> >> + /* set fd non-blocking to avoid common use cases (like reading from a >> + * named pipe) from hanging the agent >> + */ >> + qemu_set_nonblock(fileno(fh)); >> + >> fd = guest_file_handle_add(fh, errp); >> if (fd < 0) { >> CloseHandle(&fh); >> diff --git a/util/oslib-win32.c b/util/oslib-win32.c >> index 08f5a9c..f19aed5 100644 >> --- a/util/oslib-win32.c >> +++ b/util/oslib-win32.c >> @@ -121,17 +121,59 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) >> } >> #endif /* CONFIG_LOCALTIME_R */ >> >> -void qemu_set_block(int fd) >> +static void qemu_set_fd_nonblocking(int fd, bool nonblocking) >> { >> - unsigned long opt = 0; >> - WSAEventSelect(fd, NULL, 0); >> + HANDLE handle; >> + DWORD file_type, pipe_state; >> + >> + handle = (HANDLE)_get_osfhandle(fd); >> + if (handle == INVALID_HANDLE_VALUE) { >> + return; >> + } >> + >> + file_type = GetFileType(handle); >> + if (file_type != FILE_TYPE_PIPE) { >> + return; >> + } >> + >> + /* If file_type == FILE_TYPE_PIPE, according to msdn >> + * the specified file is socket or named pipe */ ... or an anonymous pipe. >> + if (GetNamedPipeHandleState(handle, &pipe_state, NULL, >> + NULL, NULL, NULL, 0)) { >> + /* The fd is named pipe fd */ pipe_state could be declared here. >> + if (!nonblocking == !(pipe_state & PIPE_NOWAIT)) { >> + /* In this case we do not need perform any operation, because >> + * nonblocking = true and PIPE_NOWAIT is already set or >> + * nonblocking = false and PIPE_NOWAIT is not set */ >> + return; >> + } >> + >> + if (nonblocking) { >> + pipe_state |= PIPE_NOWAIT; >> + } else { >> + pipe_state &= ~PIPE_NOWAIT; >> + } >> + >> + SetNamedPipeHandleState(handle, &pipe_state, NULL, NULL); >> + return; >> + } >> + >> + /* The fd is socket fd */ >> + unsigned long opt = (unsigned long)nonblocking; The QEMU style still requires variable declarations at the beginning of a code block. >> + if (!nonblocking) { >> + WSAEventSelect(fd, NULL, 0); >> + } >> ioctlsocket(fd, FIONBIO, &opt); >> } >> >> +void qemu_set_block(int fd) >> +{ >> + qemu_set_fd_nonblocking(fd, false); >> +} >> + >> void qemu_set_nonblock(int fd) >> { >> - unsigned long opt = 1; >> - ioctlsocket(fd, FIONBIO, &opt); >> + qemu_set_fd_nonblocking(fd, true); >> qemu_fd_register(fd); > > This still potentially calls qemu_fd_register() on a non-socket FD as > noted in prior review. I think the fix is trivial, but if you can > change and re-test that would be ideal. Yes. > > Since guest-file* already supports reading/writing to w32 pipes I can > pick this up during soft-freeze if it comes to that. > > Since we're still taking the approach of generalizing > qemu_set_nonblock() for win32 I'd really prefer to get Stefan's > Ack/Reviewed-by before applying. > >> } I'm sorry that I cannot run any tests, but as far as I can see, the code will be fine if all the notes are taken into account. Regards Stefan
On 10/12/2015 09:39 PM, Stefan Weil wrote: > Hi, > > please see my inline comments below. > > Am 12.10.2015 um 19:38 schrieb Michael Roth: >> Quoting Denis V. Lunev (2015-10-07 05:59:34) >>> From: Olga Krishtal <okrishtal@virtuozzo.com> >>> >>> Set fd non-blocking to avoid common use cases (like reading from a >>> named pipe) from hanging the agent. This was missed in the original >>> code. >>> >>> Restore compatibility with Posix implementation. >>> >>> The patch adds Win32 specific implementation of qemu_set_nonblock. >>> >>> On Windows OS there is a separate API for changing flags of file, pipes >>> and sockets. Portable way to change file descriptor flags requires >>> to detect file descriptor type and proper actions depending of that >>> type. The patch adds wrapper qemu_set_fd_nonblocking into Windows specific >>> code to handle this stuff properly. >>> >>> The only problem is that qemu_set_nonblock is void but this should not >>> be a big deal. >>> >>> Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com> >>> Signed-off-by: Denis V. Lunev <den@openvz.org> >>> Reviewed-by: Yuri Pudgorodskiy <yur@virtuozzo.com> >>> CC: Michael Roth <mdroth@linux.vnet.ibm.com> >>> CC: Stefan Weil <sw@weilnetz.de> >>> --- >>> qga/commands-win32.c | 6 ++++++ >>> util/oslib-win32.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++----- >>> 2 files changed, 53 insertions(+), 5 deletions(-) >>> >>> diff --git a/qga/commands-win32.c b/qga/commands-win32.c >>> index 3374678..3274417 100644 >>> --- a/qga/commands-win32.c >>> +++ b/qga/commands-win32.c >>> @@ -34,6 +34,7 @@ >>> #include "qapi/qmp/qerror.h" >>> #include "qemu/queue.h" >>> #include "qemu/host-utils.h" >>> +#include "qemu/sockets.h" >>> >>> #ifndef SHTDN_REASON_FLAG_PLANNED >>> #define SHTDN_REASON_FLAG_PLANNED 0x80000000 >>> @@ -158,6 +159,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, >>> return -1; >>> } >>> >>> + /* set fd non-blocking to avoid common use cases (like reading from a >>> + * named pipe) from hanging the agent >>> + */ >>> + qemu_set_nonblock(fileno(fh)); >>> + >>> fd = guest_file_handle_add(fh, errp); >>> if (fd < 0) { >>> CloseHandle(&fh); >>> diff --git a/util/oslib-win32.c b/util/oslib-win32.c >>> index 08f5a9c..f19aed5 100644 >>> --- a/util/oslib-win32.c >>> +++ b/util/oslib-win32.c >>> @@ -121,17 +121,59 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) >>> } >>> #endif /* CONFIG_LOCALTIME_R */ >>> >>> -void qemu_set_block(int fd) >>> +static void qemu_set_fd_nonblocking(int fd, bool nonblocking) >>> { >>> - unsigned long opt = 0; >>> - WSAEventSelect(fd, NULL, 0); >>> + HANDLE handle; >>> + DWORD file_type, pipe_state; >>> + >>> + handle = (HANDLE)_get_osfhandle(fd); >>> + if (handle == INVALID_HANDLE_VALUE) { >>> + return; >>> + } >>> + >>> + file_type = GetFileType(handle); >>> + if (file_type != FILE_TYPE_PIPE) { >>> + return; >>> + } >>> + >>> + /* If file_type == FILE_TYPE_PIPE, according to msdn >>> + * the specified file is socket or named pipe */ > ... or an anonymous pipe. ok >>> + if (GetNamedPipeHandleState(handle, &pipe_state, NULL, >>> + NULL, NULL, NULL, 0)) { >>> + /* The fd is named pipe fd */ > pipe_state could be declared here. not ok. pipe_state is initialized in GetNamedPipeHandleState above, which is in the main scope of the function >>> + if (!nonblocking == !(pipe_state & PIPE_NOWAIT)) { >>> + /* In this case we do not need perform any operation, because >>> + * nonblocking = true and PIPE_NOWAIT is already set or >>> + * nonblocking = false and PIPE_NOWAIT is not set */ >>> + return; >>> + } >>> + >>> + if (nonblocking) { >>> + pipe_state |= PIPE_NOWAIT; >>> + } else { >>> + pipe_state &= ~PIPE_NOWAIT; >>> + } >>> + >>> + SetNamedPipeHandleState(handle, &pipe_state, NULL, NULL); >>> + return; >>> + } >>> + >>> + /* The fd is socket fd */ >>> + unsigned long opt = (unsigned long)nonblocking; > The QEMU style still requires variable declarations at the beginning of > a code block. ok >>> + if (!nonblocking) { >>> + WSAEventSelect(fd, NULL, 0); >>> + } >>> ioctlsocket(fd, FIONBIO, &opt); >>> } >>> >>> +void qemu_set_block(int fd) >>> +{ >>> + qemu_set_fd_nonblocking(fd, false); >>> +} >>> + >>> void qemu_set_nonblock(int fd) >>> { >>> - unsigned long opt = 1; >>> - ioctlsocket(fd, FIONBIO, &opt); >>> + qemu_set_fd_nonblocking(fd, true); >>> qemu_fd_register(fd); >> This still potentially calls qemu_fd_register() on a non-socket FD as >> noted in prior review. I think the fix is trivial, but if you can >> change and re-test that would be ideal. > Yes. sure :) already discussed >> Since guest-file* already supports reading/writing to w32 pipes I can >> pick this up during soft-freeze if it comes to that. >> >> Since we're still taking the approach of generalizing >> qemu_set_nonblock() for win32 I'd really prefer to get Stefan's >> Ack/Reviewed-by before applying. >> >>> } > I'm sorry that I cannot run any tests, but as far as I can see, > the code will be fine if all the notes are taken into account. > > Regards > Stefan >
diff --git a/qga/commands-win32.c b/qga/commands-win32.c index 3374678..3274417 100644 --- a/qga/commands-win32.c +++ b/qga/commands-win32.c @@ -34,6 +34,7 @@ #include "qapi/qmp/qerror.h" #include "qemu/queue.h" #include "qemu/host-utils.h" +#include "qemu/sockets.h" #ifndef SHTDN_REASON_FLAG_PLANNED #define SHTDN_REASON_FLAG_PLANNED 0x80000000 @@ -158,6 +159,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, return -1; } + /* set fd non-blocking to avoid common use cases (like reading from a + * named pipe) from hanging the agent + */ + qemu_set_nonblock(fileno(fh)); + fd = guest_file_handle_add(fh, errp); if (fd < 0) { CloseHandle(&fh); diff --git a/util/oslib-win32.c b/util/oslib-win32.c index 08f5a9c..f19aed5 100644 --- a/util/oslib-win32.c +++ b/util/oslib-win32.c @@ -121,17 +121,59 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) } #endif /* CONFIG_LOCALTIME_R */ -void qemu_set_block(int fd) +static void qemu_set_fd_nonblocking(int fd, bool nonblocking) { - unsigned long opt = 0; - WSAEventSelect(fd, NULL, 0); + HANDLE handle; + DWORD file_type, pipe_state; + + handle = (HANDLE)_get_osfhandle(fd); + if (handle == INVALID_HANDLE_VALUE) { + return; + } + + file_type = GetFileType(handle); + if (file_type != FILE_TYPE_PIPE) { + return; + } + + /* If file_type == FILE_TYPE_PIPE, according to msdn + * the specified file is socket or named pipe */ + if (GetNamedPipeHandleState(handle, &pipe_state, NULL, + NULL, NULL, NULL, 0)) { + /* The fd is named pipe fd */ + if (!nonblocking == !(pipe_state & PIPE_NOWAIT)) { + /* In this case we do not need perform any operation, because + * nonblocking = true and PIPE_NOWAIT is already set or + * nonblocking = false and PIPE_NOWAIT is not set */ + return; + } + + if (nonblocking) { + pipe_state |= PIPE_NOWAIT; + } else { + pipe_state &= ~PIPE_NOWAIT; + } + + SetNamedPipeHandleState(handle, &pipe_state, NULL, NULL); + return; + } + + /* The fd is socket fd */ + unsigned long opt = (unsigned long)nonblocking; + if (!nonblocking) { + WSAEventSelect(fd, NULL, 0); + } ioctlsocket(fd, FIONBIO, &opt); } +void qemu_set_block(int fd) +{ + qemu_set_fd_nonblocking(fd, false); +} + void qemu_set_nonblock(int fd) { - unsigned long opt = 1; - ioctlsocket(fd, FIONBIO, &opt); + qemu_set_fd_nonblocking(fd, true); qemu_fd_register(fd); }