Implement the register command of "ibm,configure-kernel-dump" RTAS call.
The register just verifies the structure of the fadump memory structure
passed by kernel, and set fadump_registered in spapr state to true.
We also store the passed fadump memory structure, which will later be
used for preserving memory for fadump boot in case of a crash.
The fadump memory structure isn't modified (other than .dump_status_flag
after the fadump is triggered, that is in a later patch).
So if the structure needs to updated, the kernel should first
de-register and re-register the structure again.
Relevant section for the register command in PAPR is:
Section 7.3.30: "ibm,configure-kernel-dump RTAS call" (PAPR v2.13)
Note: The fadump registration is done, but triggering fadump on an
os-term rtas call is done in later patches. Hence QEMU will just shutdown
on a kernel crash due to no special handling for fadump in ibm,os-term
Signed-off-by: Aditya Gupta <adit...@linux.ibm.com>
---
hw/ppc/spapr_fadump.c | 111 ++++++++++++++++++++++++++++++++--
hw/ppc/spapr_rtas.c | 2 +-
include/hw/ppc/spapr_fadump.h | 2 +-
3 files changed, 108 insertions(+), 7 deletions(-)
diff --git a/hw/ppc/spapr_fadump.c b/hw/ppc/spapr_fadump.c
index 20b7b804c485..9c7fb9e12b16 100644
--- a/hw/ppc/spapr_fadump.c
+++ b/hw/ppc/spapr_fadump.c
@@ -5,18 +5,119 @@
*/
#include "qemu/osdep.h"
+#include "qemu/log.h"
#include "hw/ppc/spapr.h"
/*
* Handle the "FADUMP_CMD_REGISTER" command in 'ibm,configure-kernel-dump'
*
+ * Note: Any changes made by the kernel to the fadump memory struct won't
+ * reflect in QEMU after the 'ibm,configure-kernel-dump' RTAS call has
returned,
+ * as we store the passed fadump memory structure passed during fadump
+ * registration.
+ * Kernel has to invalidate & re-register fadump, if it intends to make any
+ * changes to the fadump memory structure
+ *
* Returns:
- * * RTAS_OUT_HW_ERROR: Not implemented/Misc issue such as memory access
- * failures
+ * * RTAS_OUT_SUCCESS: On successful registration
+ * * RTAS_OUT_PARAM_ERROR: If parameters are not correct, eg. too many
+ * sections, invalid memory addresses that we are
+ * unable to read, etc
+ * * RTAS_OUT_DUMP_ALREADY_REGISTERED: Dump already registered
+ * * RTAS_OUT_HW_ERROR: Misc issue such as memory access failures
*/
-uint32_t do_fadump_register(void)
+uint32_t do_fadump_register(SpaprMachineState *spapr, target_ulong args)
{
- /* WIP: FADUMP_CMD_REGISTER implemented in future patch */
+ FadumpSectionHeader header;
+ FadumpSection regions[FADUMP_MAX_SECTIONS] = {0};
+ target_ulong fdm_addr = rtas_ld(args, 1);
+ target_ulong fdm_size = rtas_ld(args, 2);
+ AddressSpace *default_as = &address_space_memory;
+ MemTxResult io_result;
+ MemTxAttrs attrs;
+ uint64_t next_section_addr;
+ uint16_t dump_num_sections;
+
+ /* Mark the memory transaction as privileged memory access */
+ attrs.user = 0;
+ attrs.memory = 1;
+
+ if (spapr->fadump_registered) {
+ /* FADump already registered */
+ return RTAS_OUT_DUMP_ALREADY_REGISTERED;
+ }
+
+ if (spapr->fadump_dump_active == 1) {
+ return RTAS_OUT_DUMP_ACTIVE;
+ }
+
+ if (fdm_size < sizeof(FadumpSectionHeader)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "FADump: Header size is invalid: %lu\n", fdm_size);
+ return RTAS_OUT_PARAM_ERROR;
+ }
+
+ /* Ensure fdm_addr points to a valid RMR-memory/RMA-memory buffer */
+ if ((fdm_addr <= 0) || ((fdm_addr + fdm_size) > spapr->rma_size)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "FADump: Invalid fdm address: %ld\n", fdm_addr);
+ return RTAS_OUT_PARAM_ERROR;
+ }
+
+ /* Try to read the passed fadump header */
+ io_result = address_space_read(default_as, fdm_addr, attrs,
+ &header, sizeof(header));
+ if (io_result != MEMTX_OK) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "FADump: Unable to read fdm address: %ld\n", fdm_addr);
+
+ return RTAS_OUT_HW_ERROR;
+ }
+
+ /* Verify that we understand the fadump header version */
+ if (header.dump_format_version != cpu_to_be32(FADUMP_VERSION)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "FADump: Unknown fadump header version: 0x%x\n",
+ header.dump_format_version);
+ return RTAS_OUT_PARAM_ERROR;
+ }
+
+ /* Reset dump status flags */
+ header.dump_status_flag = 0;
+
+ dump_num_sections = be16_to_cpu(header.dump_num_sections);
+
+ if (dump_num_sections > FADUMP_MAX_SECTIONS) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "FADump: Too many sections: %d sections\n", dump_num_sections);
+ return RTAS_OUT_PARAM_ERROR;
+ }
+
+ next_section_addr =
+ fdm_addr +
+ be32_to_cpu(header.offset_first_dump_section);
+
+ for (int i = 0; i < dump_num_sections; ++i) {
+ /* Read the fadump section from memory */
+ io_result = address_space_read(default_as, next_section_addr, attrs,
+ ®ions[i], sizeof(regions[i]));
+ if (io_result != MEMTX_OK) {
+ qemu_log_mask(LOG_UNIMP,
+ "FADump: Unable to read fadump %dth section\n", i);
+ return RTAS_OUT_PARAM_ERROR;
+ }
+
+ next_section_addr += sizeof(regions[i]);
+ }
+
+ spapr->fadump_registered = true;
+ spapr->fadump_dump_active = false;
+
+ /* Store the registered fadump memory struct */
+ spapr->registered_fdm.header = header;
+ for (int i = 0; i < dump_num_sections; ++i) {
+ spapr->registered_fdm.rgn[i] = regions[i];
+ }
- return RTAS_OUT_HW_ERROR;
+ return RTAS_OUT_SUCCESS;
}
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index b8bfa9c33fb5..0454938a01e9 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -366,7 +366,7 @@ static void rtas_configure_kernel_dump(PowerPCCPU *cpu,
switch (cmd) {
case FADUMP_CMD_REGISTER:
- ret_val = do_fadump_register();
+ ret_val = do_fadump_register(spapr, args);
if (ret_val != RTAS_OUT_SUCCESS) {
rtas_st(rets, 0, ret_val);
return;
diff --git a/include/hw/ppc/spapr_fadump.h b/include/hw/ppc/spapr_fadump.h
index 45109fd9e137..6abbcb44f353 100644
--- a/include/hw/ppc/spapr_fadump.h
+++ b/include/hw/ppc/spapr_fadump.h
@@ -65,5 +65,5 @@ struct FadumpMemStruct {
FadumpSection rgn[FADUMP_MAX_SECTIONS];
};
-uint32_t do_fadump_register(void);
+uint32_t do_fadump_register(struct SpaprMachineState *, target_ulong);
#endif /* PPC_SPAPR_FADUMP_H */
--
2.48.1
