| Message ID | 20240827021847.218390-2-rowanbhart@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | plugins: add plugin API to read guest memory | expand |
On 8/26/24 19:18, Rowan Hart wrote: > Signed-off-by: Rowan Hart <rowanbhart@gmail.com> > --- > include/qemu/qemu-plugin.h | 32 +++++++++++++++++++++++++++++++- > plugins/api.c | 20 ++++++++++++++++++++ > plugins/qemu-plugins.symbols | 1 + > 3 files changed, 52 insertions(+), 1 deletion(-) > > diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h > index c71c705b69..10f9db8cdc 100644 > --- a/include/qemu/qemu-plugin.h > +++ b/include/qemu/qemu-plugin.h > @@ -57,11 +57,19 @@ typedef uint64_t qemu_plugin_id_t; > * - Remove qemu_plugin_register_vcpu_{tb, insn, mem}_exec_inline. > * Those functions are replaced by *_per_vcpu variants, which guarantee > * thread-safety for operations. > + * > + * version 3: > + * - modified arguments and return value of qemu_plugin_insn_data to copy > + * the data into a user-provided buffer instead of returning a pointer > + * to the data. > + * > + * version 4: > + * - added qemu_plugin_read_memory_vaddr > */ > > extern QEMU_PLUGIN_EXPORT int qemu_plugin_version; > > -#define QEMU_PLUGIN_VERSION 3 > +#define QEMU_PLUGIN_VERSION 4 > > /** > * struct qemu_info_t - system information for plugins > @@ -852,6 +860,28 @@ typedef struct { > QEMU_PLUGIN_API > GArray *qemu_plugin_get_registers(void); > > +/** > + * qemu_plugin_read_memory_vaddr() - read from memory using a virtual address > + * > + * @addr: A virtual address to read from > + * @data: A byte array to store data into > + * @len: The number of bytes to read, starting from @addr > + Missing '*' on this line, generating an error when building doc. > + * @len bytes of data is read starting at @addr and stored into @data. If @data > + * is not large enough to hold @len bytes, it will be expanded to the necessary > + * size, reallocating if necessary. @len must be greater than 0. > + * > + * This function does not ensure writes are flushed prior to reading, so > + * callers should take care when calling this function in plugin callbacks to > + * avoid attempting to read data which may not yet be written and should use > + * the memory callback API instead. > + * > + * Returns true on success and false on failure. > + */ > +QEMU_PLUGIN_API > +bool qemu_plugin_read_memory_vaddr(uint64_t addr, > + GByteArray *data, size_t len); > + > /** > * qemu_plugin_read_register() - read register for current vCPU > * > diff --git a/plugins/api.c b/plugins/api.c > index 2ff13d09de..cb7d818918 100644 > --- a/plugins/api.c > +++ b/plugins/api.c > @@ -527,6 +527,26 @@ GArray *qemu_plugin_get_registers(void) > return create_register_handles(regs); > } > > +bool qemu_plugin_read_memory_vaddr(vaddr addr, GByteArray *data, size_t len) > +{ > + g_assert(current_cpu); > + > + if (len == 0) { > + return false; > + } > + > + g_byte_array_set_size(data, len); > + > + int result = cpu_memory_rw_debug(current_cpu, addr, data->data, > + data->len, 0); > + > + if (result < 0) { > + return false; > + } > + > + return true; > +} > + > int qemu_plugin_read_register(struct qemu_plugin_register *reg, GByteArray *buf) > { > g_assert(current_cpu); > diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols > index ca773d8d9f..3ad479a924 100644 > --- a/plugins/qemu-plugins.symbols > +++ b/plugins/qemu-plugins.symbols > @@ -20,6 +20,7 @@ > qemu_plugin_num_vcpus; > qemu_plugin_outs; > qemu_plugin_path_to_binary; > + qemu_plugin_read_memory_vaddr; > qemu_plugin_read_register; > qemu_plugin_register_atexit_cb; > qemu_plugin_register_flush_cb; Otherwise, Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org> @Rowan, for v3, you can add this "Reviewed-by: ..." line in your commit message, so it shows it was reviewed.
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h index c71c705b69..10f9db8cdc 100644 --- a/include/qemu/qemu-plugin.h +++ b/include/qemu/qemu-plugin.h @@ -57,11 +57,19 @@ typedef uint64_t qemu_plugin_id_t; * - Remove qemu_plugin_register_vcpu_{tb, insn, mem}_exec_inline. * Those functions are replaced by *_per_vcpu variants, which guarantee * thread-safety for operations. + * + * version 3: + * - modified arguments and return value of qemu_plugin_insn_data to copy + * the data into a user-provided buffer instead of returning a pointer + * to the data. + * + * version 4: + * - added qemu_plugin_read_memory_vaddr */ extern QEMU_PLUGIN_EXPORT int qemu_plugin_version; -#define QEMU_PLUGIN_VERSION 3 +#define QEMU_PLUGIN_VERSION 4 /** * struct qemu_info_t - system information for plugins @@ -852,6 +860,28 @@ typedef struct { QEMU_PLUGIN_API GArray *qemu_plugin_get_registers(void); +/** + * qemu_plugin_read_memory_vaddr() - read from memory using a virtual address + * + * @addr: A virtual address to read from + * @data: A byte array to store data into + * @len: The number of bytes to read, starting from @addr + + * @len bytes of data is read starting at @addr and stored into @data. If @data + * is not large enough to hold @len bytes, it will be expanded to the necessary + * size, reallocating if necessary. @len must be greater than 0. + * + * This function does not ensure writes are flushed prior to reading, so + * callers should take care when calling this function in plugin callbacks to + * avoid attempting to read data which may not yet be written and should use + * the memory callback API instead. + * + * Returns true on success and false on failure. + */ +QEMU_PLUGIN_API +bool qemu_plugin_read_memory_vaddr(uint64_t addr, + GByteArray *data, size_t len); + /** * qemu_plugin_read_register() - read register for current vCPU * diff --git a/plugins/api.c b/plugins/api.c index 2ff13d09de..cb7d818918 100644 --- a/plugins/api.c +++ b/plugins/api.c @@ -527,6 +527,26 @@ GArray *qemu_plugin_get_registers(void) return create_register_handles(regs); } +bool qemu_plugin_read_memory_vaddr(vaddr addr, GByteArray *data, size_t len) +{ + g_assert(current_cpu); + + if (len == 0) { + return false; + } + + g_byte_array_set_size(data, len); + + int result = cpu_memory_rw_debug(current_cpu, addr, data->data, + data->len, 0); + + if (result < 0) { + return false; + } + + return true; +} + int qemu_plugin_read_register(struct qemu_plugin_register *reg, GByteArray *buf) { g_assert(current_cpu); diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols index ca773d8d9f..3ad479a924 100644 --- a/plugins/qemu-plugins.symbols +++ b/plugins/qemu-plugins.symbols @@ -20,6 +20,7 @@ qemu_plugin_num_vcpus; qemu_plugin_outs; qemu_plugin_path_to_binary; + qemu_plugin_read_memory_vaddr; qemu_plugin_read_register; qemu_plugin_register_atexit_cb; qemu_plugin_register_flush_cb;
Signed-off-by: Rowan Hart <rowanbhart@gmail.com> --- include/qemu/qemu-plugin.h | 32 +++++++++++++++++++++++++++++++- plugins/api.c | 20 ++++++++++++++++++++ plugins/qemu-plugins.symbols | 1 + 3 files changed, 52 insertions(+), 1 deletion(-)