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Diffstat (limited to 'slirp/vmstate.h')
| -rw-r--r-- | slirp/vmstate.h | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/slirp/vmstate.h b/slirp/vmstate.h new file mode 100644 index 0000000000..cfa7b8c825 --- /dev/null +++ b/slirp/vmstate.h @@ -0,0 +1,396 @@ +/* + * QEMU migration/snapshot declarations + * + * Copyright (c) 2009-2011 Red Hat, Inc. + * + * Original author: Juan Quintela <quintela@redhat.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#ifndef VMSTATE_H_ +#define VMSTATE_H_ + +#include <unistd.h> +#include <stdint.h> +#include <stdbool.h> +#include "slirp.h" +#include "stream.h" + +#define stringify(s) tostring(s) +#define tostring(s) #s + +typedef struct VMStateInfo VMStateInfo; +typedef struct VMStateDescription VMStateDescription; +typedef struct VMStateField VMStateField; + +int slirp_vmstate_save_state(SlirpOStream *f, const VMStateDescription *vmsd, + void *opaque); +int slirp_vmstate_load_state(SlirpIStream *f, const VMStateDescription *vmsd, + void *opaque, int version_id); + +/* VMStateInfo allows customized migration of objects that don't fit in + * any category in VMStateFlags. Additional information is always passed + * into get and put in terms of field and vmdesc parameters. However + * these two parameters should only be used in cases when customized + * handling is needed, such as QTAILQ. For primitive data types such as + * integer, field and vmdesc parameters should be ignored inside get/put. + */ +struct VMStateInfo { + const char *name; + int (*get)(SlirpIStream *f, void *pv, size_t size, const VMStateField *field); + int (*put)(SlirpOStream *f, void *pv, size_t size, const VMStateField *field); +}; + +enum VMStateFlags { + /* Ignored */ + VMS_SINGLE = 0x001, + + /* The struct member at opaque + VMStateField.offset is a pointer + * to the actual field (e.g. struct a { uint8_t *b; + * }). Dereference the pointer before using it as basis for + * further pointer arithmetic (see e.g. VMS_ARRAY). Does not + * affect the meaning of VMStateField.num_offset or + * VMStateField.size_offset; see VMS_VARRAY* and VMS_VBUFFER for + * those. */ + VMS_POINTER = 0x002, + + /* The field is an array of fixed size. VMStateField.num contains + * the number of entries in the array. The size of each entry is + * given by VMStateField.size and / or opaque + + * VMStateField.size_offset; see VMS_VBUFFER and + * VMS_MULTIPLY. Each array entry will be processed individually + * (VMStateField.info.get()/put() if VMS_STRUCT is not set, + * recursion into VMStateField.vmsd if VMS_STRUCT is set). May not + * be combined with VMS_VARRAY*. */ + VMS_ARRAY = 0x004, + + /* The field is itself a struct, containing one or more + * fields. Recurse into VMStateField.vmsd. Most useful in + * combination with VMS_ARRAY / VMS_VARRAY*, recursing into each + * array entry. */ + VMS_STRUCT = 0x008, + + /* The field is an array of variable size. The int32_t at opaque + + * VMStateField.num_offset contains the number of entries in the + * array. See the VMS_ARRAY description regarding array handling + * in general. May not be combined with VMS_ARRAY or any other + * VMS_VARRAY*. */ + VMS_VARRAY_INT32 = 0x010, + + /* Ignored */ + VMS_BUFFER = 0x020, + + /* The field is a (fixed-size or variable-size) array of pointers + * (e.g. struct a { uint8_t *b[]; }). Dereference each array entry + * before using it. Note: Does not imply any one of VMS_ARRAY / + * VMS_VARRAY*; these need to be set explicitly. */ + VMS_ARRAY_OF_POINTER = 0x040, + + /* The field is an array of variable size. The uint16_t at opaque + * + VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS) + * contains the number of entries in the array. See the VMS_ARRAY + * description regarding array handling in general. May not be + * combined with VMS_ARRAY or any other VMS_VARRAY*. */ + VMS_VARRAY_UINT16 = 0x080, + + /* The size of the individual entries (a single array entry if + * VMS_ARRAY or any of VMS_VARRAY* are set, or the field itself if + * neither is set) is variable (i.e. not known at compile-time), + * but the same for all entries. Use the int32_t at opaque + + * VMStateField.size_offset (subject to VMS_MULTIPLY) to determine + * the size of each (and every) entry. */ + VMS_VBUFFER = 0x100, + + /* Multiply the entry size given by the int32_t at opaque + + * VMStateField.size_offset (see VMS_VBUFFER description) with + * VMStateField.size to determine the number of bytes to be + * allocated. Only valid in combination with VMS_VBUFFER. */ + VMS_MULTIPLY = 0x200, + + /* The field is an array of variable size. The uint8_t at opaque + + * VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS) + * contains the number of entries in the array. See the VMS_ARRAY + * description regarding array handling in general. May not be + * combined with VMS_ARRAY or any other VMS_VARRAY*. */ + VMS_VARRAY_UINT8 = 0x400, + + /* The field is an array of variable size. The uint32_t at opaque + * + VMStateField.num_offset (subject to VMS_MULTIPLY_ELEMENTS) + * contains the number of entries in the array. See the VMS_ARRAY + * description regarding array handling in general. May not be + * combined with VMS_ARRAY or any other VMS_VARRAY*. */ + VMS_VARRAY_UINT32 = 0x800, + + /* Fail loading the serialised VM state if this field is missing + * from the input. */ + VMS_MUST_EXIST = 0x1000, + + /* When loading serialised VM state, allocate memory for the + * (entire) field. Only valid in combination with + * VMS_POINTER. Note: Not all combinations with other flags are + * currently supported, e.g. VMS_ALLOC|VMS_ARRAY_OF_POINTER won't + * cause the individual entries to be allocated. */ + VMS_ALLOC = 0x2000, + + /* Multiply the number of entries given by the integer at opaque + + * VMStateField.num_offset (see VMS_VARRAY*) with VMStateField.num + * to determine the number of entries in the array. Only valid in + * combination with one of VMS_VARRAY*. */ + VMS_MULTIPLY_ELEMENTS = 0x4000, + + /* A structure field that is like VMS_STRUCT, but uses + * VMStateField.struct_version_id to tell which version of the + * structure we are referencing to use. */ + VMS_VSTRUCT = 0x8000, +}; + +struct VMStateField { + const char *name; + size_t offset; + size_t size; + size_t start; + int num; + size_t num_offset; + size_t size_offset; + const VMStateInfo *info; + enum VMStateFlags flags; + const VMStateDescription *vmsd; + int version_id; + int struct_version_id; + bool (*field_exists)(void *opaque, int version_id); +}; + +struct VMStateDescription { + const char *name; + int version_id; + int (*pre_load)(void *opaque); + int (*post_load)(void *opaque, int version_id); + int (*pre_save)(void *opaque); + VMStateField *fields; +}; + + +extern const VMStateInfo slirp_vmstate_info_int16; +extern const VMStateInfo slirp_vmstate_info_int32; +extern const VMStateInfo slirp_vmstate_info_uint8; +extern const VMStateInfo slirp_vmstate_info_uint16; +extern const VMStateInfo slirp_vmstate_info_uint32; + +/** Put this in the stream when migrating a null pointer.*/ +#define VMS_NULLPTR_MARKER (0x30U) /* '0' */ +extern const VMStateInfo slirp_vmstate_info_nullptr; + +extern const VMStateInfo slirp_vmstate_info_buffer; +extern const VMStateInfo slirp_vmstate_info_tmp; + +#define type_check_array(t1,t2,n) ((t1(*)[n])0 - (t2*)0) +#define type_check_pointer(t1,t2) ((t1**)0 - (t2*)0) +#define typeof_field(type, field) typeof(((type *)0)->field) +#define type_check(t1,t2) ((t1*)0 - (t2*)0) + +#define vmstate_offset_value(_state, _field, _type) \ + (offsetof(_state, _field) + \ + type_check(_type, typeof_field(_state, _field))) + +#define vmstate_offset_pointer(_state, _field, _type) \ + (offsetof(_state, _field) + \ + type_check_pointer(_type, typeof_field(_state, _field))) + +#define vmstate_offset_array(_state, _field, _type, _num) \ + (offsetof(_state, _field) + \ + type_check_array(_type, typeof_field(_state, _field), _num)) + +#define vmstate_offset_buffer(_state, _field) \ + vmstate_offset_array(_state, _field, uint8_t, \ + sizeof(typeof_field(_state, _field))) + +/* In the macros below, if there is a _version, that means the macro's + * field will be processed only if the version being received is >= + * the _version specified. In general, if you add a new field, you + * would increment the structure's version and put that version + * number into the new field so it would only be processed with the + * new version. + * + * In particular, for VMSTATE_STRUCT() and friends the _version does + * *NOT* pick the version of the sub-structure. It works just as + * specified above. The version of the top-level structure received + * is passed down to all sub-structures. This means that the + * sub-structures must have version that are compatible with all the + * structures that use them. + * + * If you want to specify the version of the sub-structure, use + * VMSTATE_VSTRUCT(), which allows the specific sub-structure version + * to be directly specified. + */ + +#define VMSTATE_SINGLE_TEST(_field, _state, _test, _version, _info, _type) { \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .field_exists = (_test), \ + .size = sizeof(_type), \ + .info = &(_info), \ + .flags = VMS_SINGLE, \ + .offset = vmstate_offset_value(_state, _field, _type), \ +} + +#define VMSTATE_ARRAY(_field, _state, _num, _version, _info, _type) {\ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .num = (_num), \ + .info = &(_info), \ + .size = sizeof(_type), \ + .flags = VMS_ARRAY, \ + .offset = vmstate_offset_array(_state, _field, _type, _num), \ +} + +#define VMSTATE_STRUCT_TEST(_field, _state, _test, _version, _vmsd, _type) { \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .field_exists = (_test), \ + .vmsd = &(_vmsd), \ + .size = sizeof(_type), \ + .flags = VMS_STRUCT, \ + .offset = vmstate_offset_value(_state, _field, _type), \ +} + +#define VMSTATE_STRUCT_POINTER_V(_field, _state, _version, _vmsd, _type) { \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .vmsd = &(_vmsd), \ + .size = sizeof(_type *), \ + .flags = VMS_STRUCT|VMS_POINTER, \ + .offset = vmstate_offset_pointer(_state, _field, _type), \ +} + +#define VMSTATE_STRUCT_ARRAY_TEST(_field, _state, _num, _test, _version, _vmsd, _type) { \ + .name = (stringify(_field)), \ + .num = (_num), \ + .field_exists = (_test), \ + .version_id = (_version), \ + .vmsd = &(_vmsd), \ + .size = sizeof(_type), \ + .flags = VMS_STRUCT|VMS_ARRAY, \ + .offset = vmstate_offset_array(_state, _field, _type, _num),\ +} + +#define VMSTATE_STATIC_BUFFER(_field, _state, _version, _test, _start, _size) { \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .field_exists = (_test), \ + .size = (_size - _start), \ + .info = &slirp_vmstate_info_buffer, \ + .flags = VMS_BUFFER, \ + .offset = vmstate_offset_buffer(_state, _field) + _start, \ +} + +#define VMSTATE_VBUFFER_UINT32(_field, _state, _version, _test, _field_size) { \ + .name = (stringify(_field)), \ + .version_id = (_version), \ + .field_exists = (_test), \ + .size_offset = vmstate_offset_value(_state, _field_size, uint32_t),\ + .info = &slirp_vmstate_info_buffer, \ + .flags = VMS_VBUFFER|VMS_POINTER, \ + .offset = offsetof(_state, _field), \ +} + +#define QEMU_BUILD_BUG_ON_STRUCT(x) \ + struct { \ + int:(x) ? -1 : 1; \ + } + +#define QEMU_BUILD_BUG_ON_ZERO(x) (sizeof(QEMU_BUILD_BUG_ON_STRUCT(x)) - \ + sizeof(QEMU_BUILD_BUG_ON_STRUCT(x))) + +/* Allocate a temporary of type 'tmp_type', set tmp->parent to _state + * and execute the vmsd on the temporary. Note that we're working with + * the whole of _state here, not a field within it. + * We compile time check that: + * That _tmp_type contains a 'parent' member that's a pointer to the + * '_state' type + * That the pointer is right at the start of _tmp_type. + */ +#define VMSTATE_WITH_TMP(_state, _tmp_type, _vmsd) { \ + .name = "tmp", \ + .size = sizeof(_tmp_type) + \ + QEMU_BUILD_BUG_ON_ZERO(offsetof(_tmp_type, parent) != 0) + \ + type_check_pointer(_state, \ + typeof_field(_tmp_type, parent)), \ + .vmsd = &(_vmsd), \ + .info = &slirp_vmstate_info_tmp, \ +} + +#define VMSTATE_SINGLE(_field, _state, _version, _info, _type) \ + VMSTATE_SINGLE_TEST(_field, _state, NULL, _version, _info, _type) + +#define VMSTATE_STRUCT(_field, _state, _version, _vmsd, _type) \ + VMSTATE_STRUCT_TEST(_field, _state, NULL, _version, _vmsd, _type) + +#define VMSTATE_STRUCT_POINTER(_field, _state, _vmsd, _type) \ + VMSTATE_STRUCT_POINTER_V(_field, _state, 0, _vmsd, _type) + +#define VMSTATE_STRUCT_ARRAY(_field, _state, _num, _version, _vmsd, _type) \ + VMSTATE_STRUCT_ARRAY_TEST(_field, _state, _num, NULL, _version, \ + _vmsd, _type) + +#define VMSTATE_INT16_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_int16, int16_t) +#define VMSTATE_INT32_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_int32, int32_t) + +#define VMSTATE_UINT8_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint8, uint8_t) +#define VMSTATE_UINT16_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint16, uint16_t) +#define VMSTATE_UINT32_V(_f, _s, _v) \ + VMSTATE_SINGLE(_f, _s, _v, slirp_vmstate_info_uint32, uint32_t) + +#define VMSTATE_INT16(_f, _s) \ + VMSTATE_INT16_V(_f, _s, 0) +#define VMSTATE_INT32(_f, _s) \ + VMSTATE_INT32_V(_f, _s, 0) + +#define VMSTATE_UINT8(_f, _s) \ + VMSTATE_UINT8_V(_f, _s, 0) +#define VMSTATE_UINT16(_f, _s) \ + VMSTATE_UINT16_V(_f, _s, 0) +#define VMSTATE_UINT32(_f, _s) \ + VMSTATE_UINT32_V(_f, _s, 0) + +#define VMSTATE_UINT16_TEST(_f, _s, _t) \ + VMSTATE_SINGLE_TEST(_f, _s, _t, 0, slirp_vmstate_info_uint16, uint16_t) + +#define VMSTATE_UINT32_TEST(_f, _s, _t) \ + VMSTATE_SINGLE_TEST(_f, _s, _t, 0, slirp_vmstate_info_uint32, uint32_t) + +#define VMSTATE_INT16_ARRAY_V(_f, _s, _n, _v) \ + VMSTATE_ARRAY(_f, _s, _n, _v, slirp_vmstate_info_int16, int16_t) + +#define VMSTATE_INT16_ARRAY(_f, _s, _n) \ + VMSTATE_INT16_ARRAY_V(_f, _s, _n, 0) + +#define VMSTATE_BUFFER_V(_f, _s, _v) \ + VMSTATE_STATIC_BUFFER(_f, _s, _v, NULL, 0, sizeof(typeof_field(_s, _f))) + +#define VMSTATE_BUFFER(_f, _s) \ + VMSTATE_BUFFER_V(_f, _s, 0) + +#define VMSTATE_END_OF_LIST() \ + {} + +#endif |