| Message ID | 1727725244-105198-9-git-send-email-steven.sistare@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Live update: cpr-transfer | expand |
On Mon, Sep 30, 2024 at 12:40:39PM -0700, Steve Sistare wrote: > Define VMSTATE_FD for declaring a file descriptor field in a > VMStateDescription. > > Signed-off-by: Steve Sistare <steven.sistare@oracle.com> > --- > include/migration/vmstate.h | 9 +++++++++ > migration/vmstate-types.c | 32 ++++++++++++++++++++++++++++++++ > 2 files changed, 41 insertions(+) > > diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h > index f313f2f..a1dfab4 100644 > --- a/include/migration/vmstate.h > +++ b/include/migration/vmstate.h > @@ -230,6 +230,7 @@ extern const VMStateInfo vmstate_info_uint8; > extern const VMStateInfo vmstate_info_uint16; > extern const VMStateInfo vmstate_info_uint32; > extern const VMStateInfo vmstate_info_uint64; > +extern const VMStateInfo vmstate_info_fd; > > /** Put this in the stream when migrating a null pointer.*/ > #define VMS_NULLPTR_MARKER (0x30U) /* '0' */ > @@ -902,6 +903,9 @@ extern const VMStateInfo vmstate_info_qlist; > #define VMSTATE_UINT64_V(_f, _s, _v) \ > VMSTATE_SINGLE(_f, _s, _v, vmstate_info_uint64, uint64_t) > > +#define VMSTATE_FD_V(_f, _s, _v) \ > + VMSTATE_SINGLE(_f, _s, _v, vmstate_info_fd, int32_t) > + > #ifdef CONFIG_LINUX > > #define VMSTATE_U8_V(_f, _s, _v) \ > @@ -936,6 +940,9 @@ extern const VMStateInfo vmstate_info_qlist; > #define VMSTATE_UINT64(_f, _s) \ > VMSTATE_UINT64_V(_f, _s, 0) > > +#define VMSTATE_FD(_f, _s) \ > + VMSTATE_FD_V(_f, _s, 0) > + > #ifdef CONFIG_LINUX > > #define VMSTATE_U8(_f, _s) \ > @@ -1009,6 +1016,8 @@ extern const VMStateInfo vmstate_info_qlist; > #define VMSTATE_UINT64_TEST(_f, _s, _t) \ > VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_uint64, uint64_t) > > +#define VMSTATE_FD_TEST(_f, _s, _t) \ > + VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_fd, int32_t) > > #define VMSTATE_TIMER_PTR_TEST(_f, _s, _test) \ > VMSTATE_POINTER_TEST(_f, _s, _test, vmstate_info_timer, QEMUTimer *) > diff --git a/migration/vmstate-types.c b/migration/vmstate-types.c > index e83bfcc..6e45a4a 100644 > --- a/migration/vmstate-types.c > +++ b/migration/vmstate-types.c > @@ -314,6 +314,38 @@ const VMStateInfo vmstate_info_uint64 = { > .put = put_uint64, > }; > > +/* File descriptor communicated via SCM_RIGHTS */ > + > +static int get_fd(QEMUFile *f, void *pv, size_t size, > + const VMStateField *field) > +{ > + int32_t *v = pv; > + qemu_get_sbe32s(f, v); Why we need to send/recv the fd integer alone? Can't that change anyway across migration? What happens if we drop this (and the put side)? > + if (*v < 0) { > + return 0; > + } > + *v = qemu_file_get_fd(f); > + return 0; > +} > + > +static int put_fd(QEMUFile *f, void *pv, size_t size, > + const VMStateField *field, JSONWriter *vmdesc) > +{ > + int32_t *v = pv; > + > + qemu_put_sbe32s(f, v); > + if (*v < 0) { > + return 0; > + } > + return qemu_file_put_fd(f, *v); > +} > + > +const VMStateInfo vmstate_info_fd = { > + .name = "fd", > + .get = get_fd, > + .put = put_fd, > +}; > + > static int get_nullptr(QEMUFile *f, void *pv, size_t size, > const VMStateField *field) > > -- > 1.8.3.1 >
On 10/7/2024 12:36 PM, Peter Xu wrote: > On Mon, Sep 30, 2024 at 12:40:39PM -0700, Steve Sistare wrote: >> Define VMSTATE_FD for declaring a file descriptor field in a >> VMStateDescription. >> >> Signed-off-by: Steve Sistare <steven.sistare@oracle.com> >> --- >> include/migration/vmstate.h | 9 +++++++++ >> migration/vmstate-types.c | 32 ++++++++++++++++++++++++++++++++ >> 2 files changed, 41 insertions(+) >> >> diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h >> index f313f2f..a1dfab4 100644 >> --- a/include/migration/vmstate.h >> +++ b/include/migration/vmstate.h >> @@ -230,6 +230,7 @@ extern const VMStateInfo vmstate_info_uint8; >> extern const VMStateInfo vmstate_info_uint16; >> extern const VMStateInfo vmstate_info_uint32; >> extern const VMStateInfo vmstate_info_uint64; >> +extern const VMStateInfo vmstate_info_fd; >> >> /** Put this in the stream when migrating a null pointer.*/ >> #define VMS_NULLPTR_MARKER (0x30U) /* '0' */ >> @@ -902,6 +903,9 @@ extern const VMStateInfo vmstate_info_qlist; >> #define VMSTATE_UINT64_V(_f, _s, _v) \ >> VMSTATE_SINGLE(_f, _s, _v, vmstate_info_uint64, uint64_t) >> >> +#define VMSTATE_FD_V(_f, _s, _v) \ >> + VMSTATE_SINGLE(_f, _s, _v, vmstate_info_fd, int32_t) >> + >> #ifdef CONFIG_LINUX >> >> #define VMSTATE_U8_V(_f, _s, _v) \ >> @@ -936,6 +940,9 @@ extern const VMStateInfo vmstate_info_qlist; >> #define VMSTATE_UINT64(_f, _s) \ >> VMSTATE_UINT64_V(_f, _s, 0) >> >> +#define VMSTATE_FD(_f, _s) \ >> + VMSTATE_FD_V(_f, _s, 0) >> + >> #ifdef CONFIG_LINUX >> >> #define VMSTATE_U8(_f, _s) \ >> @@ -1009,6 +1016,8 @@ extern const VMStateInfo vmstate_info_qlist; >> #define VMSTATE_UINT64_TEST(_f, _s, _t) \ >> VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_uint64, uint64_t) >> >> +#define VMSTATE_FD_TEST(_f, _s, _t) \ >> + VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_fd, int32_t) >> >> #define VMSTATE_TIMER_PTR_TEST(_f, _s, _test) \ >> VMSTATE_POINTER_TEST(_f, _s, _test, vmstate_info_timer, QEMUTimer *) >> diff --git a/migration/vmstate-types.c b/migration/vmstate-types.c >> index e83bfcc..6e45a4a 100644 >> --- a/migration/vmstate-types.c >> +++ b/migration/vmstate-types.c >> @@ -314,6 +314,38 @@ const VMStateInfo vmstate_info_uint64 = { >> .put = put_uint64, >> }; >> >> +/* File descriptor communicated via SCM_RIGHTS */ >> + >> +static int get_fd(QEMUFile *f, void *pv, size_t size, >> + const VMStateField *field) >> +{ >> + int32_t *v = pv; >> + qemu_get_sbe32s(f, v); > > Why we need to send/recv the fd integer alone? Can't that change anyway > across migration? What happens if we drop this (and the put side)? This is a remnant from cpr-exec mode, where the fd value did not change across exec, and SCM_RIGHTS was not used. I will delete it, and I will delete the mode test that appears in the "cpr-transfer mode" patch: qemu_get_sbe32s(f, v); if (*v < 0 || migrate_mode() != MIG_MODE_CPR_TRANSFER) { return 0; } - Steve >> + if (*v < 0) { >> + return 0; >> + } >> + *v = qemu_file_get_fd(f); >> + return 0; >> +} >> + >> +static int put_fd(QEMUFile *f, void *pv, size_t size, >> + const VMStateField *field, JSONWriter *vmdesc) >> +{ >> + int32_t *v = pv; >> + >> + qemu_put_sbe32s(f, v); >> + if (*v < 0) { >> + return 0; >> + } >> + return qemu_file_put_fd(f, *v); >> +} >> + >> +const VMStateInfo vmstate_info_fd = { >> + .name = "fd", >> + .get = get_fd, >> + .put = put_fd, >> +}; >> + >> static int get_nullptr(QEMUFile *f, void *pv, size_t size, >> const VMStateField *field) >> >> -- >> 1.8.3.1 >> >
diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index f313f2f..a1dfab4 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -230,6 +230,7 @@ extern const VMStateInfo vmstate_info_uint8; extern const VMStateInfo vmstate_info_uint16; extern const VMStateInfo vmstate_info_uint32; extern const VMStateInfo vmstate_info_uint64; +extern const VMStateInfo vmstate_info_fd; /** Put this in the stream when migrating a null pointer.*/ #define VMS_NULLPTR_MARKER (0x30U) /* '0' */ @@ -902,6 +903,9 @@ extern const VMStateInfo vmstate_info_qlist; #define VMSTATE_UINT64_V(_f, _s, _v) \ VMSTATE_SINGLE(_f, _s, _v, vmstate_info_uint64, uint64_t) +#define VMSTATE_FD_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, vmstate_info_fd, int32_t) + #ifdef CONFIG_LINUX #define VMSTATE_U8_V(_f, _s, _v) \ @@ -936,6 +940,9 @@ extern const VMStateInfo vmstate_info_qlist; #define VMSTATE_UINT64(_f, _s) \ VMSTATE_UINT64_V(_f, _s, 0) +#define VMSTATE_FD(_f, _s) \ + VMSTATE_FD_V(_f, _s, 0) + #ifdef CONFIG_LINUX #define VMSTATE_U8(_f, _s) \ @@ -1009,6 +1016,8 @@ extern const VMStateInfo vmstate_info_qlist; #define VMSTATE_UINT64_TEST(_f, _s, _t) \ VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_uint64, uint64_t) +#define VMSTATE_FD_TEST(_f, _s, _t) \ + VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_fd, int32_t) #define VMSTATE_TIMER_PTR_TEST(_f, _s, _test) \ VMSTATE_POINTER_TEST(_f, _s, _test, vmstate_info_timer, QEMUTimer *) diff --git a/migration/vmstate-types.c b/migration/vmstate-types.c index e83bfcc..6e45a4a 100644 --- a/migration/vmstate-types.c +++ b/migration/vmstate-types.c @@ -314,6 +314,38 @@ const VMStateInfo vmstate_info_uint64 = { .put = put_uint64, }; +/* File descriptor communicated via SCM_RIGHTS */ + +static int get_fd(QEMUFile *f, void *pv, size_t size, + const VMStateField *field) +{ + int32_t *v = pv; + qemu_get_sbe32s(f, v); + if (*v < 0) { + return 0; + } + *v = qemu_file_get_fd(f); + return 0; +} + +static int put_fd(QEMUFile *f, void *pv, size_t size, + const VMStateField *field, JSONWriter *vmdesc) +{ + int32_t *v = pv; + + qemu_put_sbe32s(f, v); + if (*v < 0) { + return 0; + } + return qemu_file_put_fd(f, *v); +} + +const VMStateInfo vmstate_info_fd = { + .name = "fd", + .get = get_fd, + .put = put_fd, +}; + static int get_nullptr(QEMUFile *f, void *pv, size_t size, const VMStateField *field)
Define VMSTATE_FD for declaring a file descriptor field in a VMStateDescription. Signed-off-by: Steve Sistare <steven.sistare@oracle.com> --- include/migration/vmstate.h | 9 +++++++++ migration/vmstate-types.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+)