[PATCH v3 1/5] Add a new optional ",cma" suffix to the crashkernel= command line option

[Jiri Bohac <jbohac@suse.cz>]

Add a new cma_size parameter to parse_crashkernel().
When not NULL, call __parse_crashkernel to parse the CMA
reservation size from "crashkernel=size,cma" and store it
in cma_size.

Set cma_size to NULL in all calls to parse_crashkernel().

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
---
 arch/arm/kernel/setup.c              |  2 +-
 arch/arm64/mm/init.c                 |  2 +-
 arch/loongarch/kernel/setup.c        |  2 +-
 arch/mips/kernel/setup.c             |  2 +-
 arch/powerpc/kernel/fadump.c         |  2 +-
 arch/powerpc/kexec/core.c            |  2 +-
 arch/powerpc/mm/nohash/kaslr_booke.c |  2 +-
 arch/riscv/mm/init.c                 |  2 +-
 arch/s390/kernel/setup.c             |  2 +-
 arch/sh/kernel/machine_kexec.c       |  2 +-
 arch/x86/kernel/setup.c              |  2 +-
 include/linux/crash_reserve.h        |  3 ++-
 kernel/crash_reserve.c               | 16 ++++++++++++++--
 13 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index a41c93988d2c..0bfd66c7ada0 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1004,7 +1004,7 @@ static void __init reserve_crashkernel(void)
 	total_mem = get_total_mem();
 	ret = parse_crashkernel(boot_command_line, total_mem,
 				&crash_size, &crash_base,
-				NULL, NULL);
+				NULL, NULL, NULL);
 	/* invalid value specified or crashkernel=0 */
 	if (ret || !crash_size)
 		return;
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 9c0b8d9558fc..06bf216a4b0d 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -107,7 +107,7 @@ static void __init arch_reserve_crashkernel(void)
 
 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
 				&crash_size, &crash_base,
-				&low_size, &high);
+				&low_size, NULL, &high);
 	if (ret)
 		return;
 
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index edcfdfcad7d2..ffdfb5407043 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -266,7 +266,7 @@ static void __init arch_reserve_crashkernel(void)
 		return;
 
 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
-				&crash_size, &crash_base, &low_size, &high);
+				&crash_size, &crash_base, &low_size, NULL, &high);
 	if (ret)
 		return;
 
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index fbfe0771317e..11b9b6b63e19 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -458,7 +458,7 @@ static void __init mips_parse_crashkernel(void)
 	total_mem = memblock_phys_mem_size();
 	ret = parse_crashkernel(boot_command_line, total_mem,
 				&crash_size, &crash_base,
-				NULL, NULL);
+				NULL, NULL, NULL);
 	if (ret != 0 || crash_size <= 0)
 		return;
 
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 4b371c738213..f90aaa2263aa 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -334,7 +334,7 @@ static __init u64 fadump_calculate_reserve_size(void)
 	 * memory at a predefined offset.
 	 */
 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
-				&size, &base, NULL, NULL);
+				&size, &base, NULL, NULL, NULL);
 	if (ret == 0 && size > 0) {
 		unsigned long max_size;
 
diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
index 58a930a47422..35f92427d282 100644
--- a/arch/powerpc/kexec/core.c
+++ b/arch/powerpc/kexec/core.c
@@ -66,7 +66,7 @@ void __init reserve_crashkernel(void)
 	total_mem_sz = memory_limit ? memory_limit : memblock_phys_mem_size();
 	/* use common parsing */
 	ret = parse_crashkernel(boot_command_line, total_mem_sz,
-			&crash_size, &crash_base, NULL, NULL);
+			&crash_size, &crash_base, NULL, NULL, NULL);
 	if (ret == 0 && crash_size > 0) {
 		crashk_res.start = crash_base;
 		crashk_res.end = crash_base + crash_size - 1;
diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 5c8d1bb98b3e..5e4897daaaea 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c
@@ -178,7 +178,7 @@ static void __init get_crash_kernel(void *fdt, unsigned long size)
 	int ret;
 
 	ret = parse_crashkernel(boot_command_line, size, &crash_size,
-				&crash_base, NULL, NULL);
+				&crash_base, NULL, NULL, NULL);
 	if (ret != 0 || crash_size == 0)
 		return;
 	if (crash_base == 0)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 15b2eda4c364..9634a800629b 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -1405,7 +1405,7 @@ static void __init arch_reserve_crashkernel(void)
 
 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
 				&crash_size, &crash_base,
-				&low_size, &high);
+				&low_size, NULL, &high);
 	if (ret)
 		return;
 
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index d78bcfe707b5..4d9b5b5d0cb2 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -607,7 +607,7 @@ static void __init reserve_crashkernel(void)
 	int rc;
 
 	rc = parse_crashkernel(boot_command_line, ident_map_size,
-			       &crash_size, &crash_base, NULL, NULL);
+			       &crash_size, &crash_base, NULL, NULL, NULL);
 
 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index 8321b31d2e19..37073ca1e0ad 100644
--- a/arch/sh/kernel/machine_kexec.c
+++ b/arch/sh/kernel/machine_kexec.c
@@ -146,7 +146,7 @@ void __init reserve_crashkernel(void)
 		return;
 
 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
-			&crash_size, &crash_base, NULL, NULL);
+			&crash_size, &crash_base, NULL, NULL, NULL);
 	if (ret == 0 && crash_size > 0) {
 		crashk_res.start = crash_base;
 		crashk_res.end = crash_base + crash_size - 1;
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index cebee310e200..853afde761a7 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -481,7 +481,7 @@ static void __init arch_reserve_crashkernel(void)
 
 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
 				&crash_size, &crash_base,
-				&low_size, &high);
+				&low_size, NULL, &high);
 	if (ret)
 		return;
 
diff --git a/include/linux/crash_reserve.h b/include/linux/crash_reserve.h
index 5a9df944fb80..a681f265a361 100644
--- a/include/linux/crash_reserve.h
+++ b/include/linux/crash_reserve.h
@@ -16,7 +16,8 @@ extern struct resource crashk_low_res;
 
 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 		unsigned long long *crash_size, unsigned long long *crash_base,
-		unsigned long long *low_size, bool *high);
+		unsigned long long *low_size, unsigned long long *cma_size,
+		bool *high);
 
 #ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
 #ifndef DEFAULT_CRASH_KERNEL_LOW_SIZE
diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c
index a620fb4b2116..4969d60c00d6 100644
--- a/kernel/crash_reserve.c
+++ b/kernel/crash_reserve.c
@@ -172,17 +172,19 @@ static int __init parse_crashkernel_simple(char *cmdline,
 
 #define SUFFIX_HIGH 0
 #define SUFFIX_LOW  1
-#define SUFFIX_NULL 2
+#define SUFFIX_CMA  2
+#define SUFFIX_NULL 3
 static __initdata char *suffix_tbl[] = {
 	[SUFFIX_HIGH] = ",high",
 	[SUFFIX_LOW]  = ",low",
+	[SUFFIX_CMA]  = ",cma",
 	[SUFFIX_NULL] = NULL,
 };
 
 /*
  * That function parses "suffix"  crashkernel command lines like
  *
- *	crashkernel=size,[high|low]
+ *	crashkernel=size,[high|low|cma]
  *
  * It returns 0 on success and -EINVAL on failure.
  */
@@ -298,9 +300,11 @@ int __init parse_crashkernel(char *cmdline,
 			     unsigned long long *crash_size,
 			     unsigned long long *crash_base,
 			     unsigned long long *low_size,
+			     unsigned long long *cma_size,
 			     bool *high)
 {
 	int ret;
+	unsigned long long __always_unused cma_base;
 
 	/* crashkernel=X[@offset] */
 	ret = __parse_crashkernel(cmdline, system_ram, crash_size,
@@ -331,6 +335,14 @@ int __init parse_crashkernel(char *cmdline,
 
 		*high = true;
 	}
+
+	/*
+	 * optional CMA reservation
+	 * cma_base is ignored
+	 */
+	if (cma_size)
+		__parse_crashkernel(cmdline, 0, cma_size,
+			&cma_base, suffix_tbl[SUFFIX_CMA]);
 #endif
 	if (!*crash_size)
 		ret = -EINVAL;

-- 
Jiri Bohac <jbohac@suse.cz>
SUSE Labs, Prague, Czechia