diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index 7e61b1e1da..3bbe3ed984 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -260,6 +260,7 @@ extern const VMStateInfo vmstate_info_timer; extern const VMStateInfo vmstate_info_buffer; extern const VMStateInfo vmstate_info_unused_buffer; extern const VMStateInfo vmstate_info_bitmap; +extern const VMStateInfo vmstate_info_qtailq; #define type_check_2darray(t1,t2,n,m) ((t1(*)[n][m])0 - (t2*)0) #define type_check_array(t1,t2,n) ((t1(*)[n])0 - (t2*)0) @@ -671,6 +672,25 @@ extern const VMStateInfo vmstate_info_bitmap; .offset = offsetof(_state, _field), \ } +/* For migrating a QTAILQ. + * Target QTAILQ needs be properly initialized. + * _type: type of QTAILQ element + * _next: name of QTAILQ entry field in QTAILQ element + * _vmsd: VMSD for QTAILQ element + * size: size of QTAILQ element + * start: offset of QTAILQ entry in QTAILQ element + */ +#define VMSTATE_QTAILQ_V(_field, _state, _version, _vmsd, _type, _next) \ +{ \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .vmsd = &(_vmsd), \ + .size = sizeof(_type), \ + .info = &vmstate_info_qtailq, \ + .offset = offsetof(_state, _field), \ + .start = offsetof(_type, _next), \ +} + /* _f : field name _f_n : num of elements field_name _n : num of elements diff --git a/include/qemu/queue.h b/include/qemu/queue.h index 342073fb4d..35292c3155 100644 --- a/include/qemu/queue.h +++ b/include/qemu/queue.h @@ -438,4 +438,64 @@ struct { \ #define QTAILQ_PREV(elm, headname, field) \ (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) +#define field_at_offset(base, offset, type) \ + ((type) (((char *) (base)) + (offset))) + +typedef struct DUMMY_Q_ENTRY DUMMY_Q_ENTRY; +typedef struct DUMMY_Q DUMMY_Q; + +struct DUMMY_Q_ENTRY { + QTAILQ_ENTRY(DUMMY_Q_ENTRY) next; +}; + +struct DUMMY_Q { + QTAILQ_HEAD(DUMMY_Q_HEAD, DUMMY_Q_ENTRY) head; +}; + +#define dummy_q ((DUMMY_Q *) 0) +#define dummy_qe ((DUMMY_Q_ENTRY *) 0) + +/* + * Offsets of layout of a tail queue head. + */ +#define QTAILQ_FIRST_OFFSET (offsetof(typeof(dummy_q->head), tqh_first)) +#define QTAILQ_LAST_OFFSET (offsetof(typeof(dummy_q->head), tqh_last)) +/* + * Raw access of elements of a tail queue + */ +#define QTAILQ_RAW_FIRST(head) \ + (*field_at_offset(head, QTAILQ_FIRST_OFFSET, void **)) +#define QTAILQ_RAW_TQH_LAST(head) \ + (*field_at_offset(head, QTAILQ_LAST_OFFSET, void ***)) + +/* + * Offsets of layout of a tail queue element. + */ +#define QTAILQ_NEXT_OFFSET (offsetof(typeof(dummy_qe->next), tqe_next)) +#define QTAILQ_PREV_OFFSET (offsetof(typeof(dummy_qe->next), tqe_prev)) + +/* + * Raw access of elements of a tail entry + */ +#define QTAILQ_RAW_NEXT(elm, entry) \ + (*field_at_offset(elm, entry + QTAILQ_NEXT_OFFSET, void **)) +#define QTAILQ_RAW_TQE_PREV(elm, entry) \ + (*field_at_offset(elm, entry + QTAILQ_PREV_OFFSET, void ***)) +/* + * Tail queue tranversal using pointer arithmetic. + */ +#define QTAILQ_RAW_FOREACH(elm, head, entry) \ + for ((elm) = QTAILQ_RAW_FIRST(head); \ + (elm); \ + (elm) = QTAILQ_RAW_NEXT(elm, entry)) +/* + * Tail queue insertion using pointer arithmetic. + */ +#define QTAILQ_RAW_INSERT_TAIL(head, elm, entry) do { \ + QTAILQ_RAW_NEXT(elm, entry) = NULL; \ + QTAILQ_RAW_TQE_PREV(elm, entry) = QTAILQ_RAW_TQH_LAST(head); \ + *QTAILQ_RAW_TQH_LAST(head) = (elm); \ + QTAILQ_RAW_TQH_LAST(head) = &QTAILQ_RAW_NEXT(elm, entry); \ +} while (/*CONSTCOND*/0) + #endif /* QEMU_SYS_QUEUE_H */ diff --git a/migration/trace-events b/migration/trace-events index 94134f700b..c46f9e98df 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -52,6 +52,10 @@ vmstate_n_elems(const char *name, int n_elems) "%s: %d" vmstate_subsection_load(const char *parent) "%s" vmstate_subsection_load_bad(const char *parent, const char *sub, const char *sub2) "%s: %s/%s" vmstate_subsection_load_good(const char *parent) "%s" +get_qtailq(const char *name, int version_id) "%s v%d" +get_qtailq_end(const char *name, const char *reason, int val) "%s %s/%d" +put_qtailq(const char *name, int version_id) "%s v%d" +put_qtailq_end(const char *name, const char *reason) "%s %s" # migration/qemu-file.c qemu_file_fclose(void) "" diff --git a/migration/vmstate.c b/migration/vmstate.c index 7b4bd6e835..2f9d4ba160 100644 --- a/migration/vmstate.c +++ b/migration/vmstate.c @@ -5,6 +5,7 @@ #include "migration/vmstate.h" #include "qemu/bitops.h" #include "qemu/error-report.h" +#include "qemu/queue.h" #include "trace.h" #include "migration/qjson.h" @@ -965,3 +966,71 @@ const VMStateInfo vmstate_info_bitmap = { .get = get_bitmap, .put = put_bitmap, }; + +/* get for QTAILQ + * meta data about the QTAILQ is encoded in a VMStateField structure + */ +static int get_qtailq(QEMUFile *f, void *pv, size_t unused_size, + VMStateField *field) +{ + int ret = 0; + const VMStateDescription *vmsd = field->vmsd; + /* size of a QTAILQ element */ + size_t size = field->size; + /* offset of the QTAILQ entry in a QTAILQ element */ + size_t entry_offset = field->start; + int version_id = field->version_id; + void *elm; + + trace_get_qtailq(vmsd->name, version_id); + if (version_id > vmsd->version_id) { + error_report("%s %s", vmsd->name, "too new"); + trace_get_qtailq_end(vmsd->name, "too new", -EINVAL); + + return -EINVAL; + } + if (version_id < vmsd->minimum_version_id) { + error_report("%s %s", vmsd->name, "too old"); + trace_get_qtailq_end(vmsd->name, "too old", -EINVAL); + return -EINVAL; + } + + while (qemu_get_byte(f)) { + elm = g_malloc(size); + ret = vmstate_load_state(f, vmsd, elm, version_id); + if (ret) { + return ret; + } + QTAILQ_RAW_INSERT_TAIL(pv, elm, entry_offset); + } + + trace_get_qtailq_end(vmsd->name, "end", ret); + return ret; +} + +/* put for QTAILQ */ +static int put_qtailq(QEMUFile *f, void *pv, size_t unused_size, + VMStateField *field, QJSON *vmdesc) +{ + const VMStateDescription *vmsd = field->vmsd; + /* offset of the QTAILQ entry in a QTAILQ element*/ + size_t entry_offset = field->start; + void *elm; + + trace_put_qtailq(vmsd->name, vmsd->version_id); + + QTAILQ_RAW_FOREACH(elm, pv, entry_offset) { + qemu_put_byte(f, true); + vmstate_save_state(f, vmsd, elm, vmdesc); + } + qemu_put_byte(f, false); + + trace_put_qtailq_end(vmsd->name, "end"); + + return 0; +} +const VMStateInfo vmstate_info_qtailq = { + .name = "qtailq", + .get = get_qtailq, + .put = put_qtailq, +};