s390/sclp: Determine HSA size dynamically for zfcpdump

Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

5 files changed, 20 insertions, 15 deletions

diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index 7dc7f9c63b65..593069201bb9 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -57,5 +57,7 @@ bool sclp_has_vt220(void);
 int sclp_pci_configure(u32 fid);
 int sclp_pci_deconfigure(u32 fid);
 int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode);
+void sclp_hsa_size_detect(void);
+unsigned long sclp_get_hsa_size(void);
 
 #endif /* _ASM_S390_SCLP_H */
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index df802ee14af6..94cfbe442f12 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -107,9 +107,6 @@ void create_mem_hole(struct mem_chunk mem_chunk[], unsigned long addr,
 #define MACHINE_HAS_RRBM	(S390_lowcore.machine_flags & MACHINE_FLAG_RRBM)
 #endif /* CONFIG_64BIT */
 
-#define ZFCPDUMP_HSA_SIZE	(32UL<<20)
-#define ZFCPDUMP_HSA_SIZE_MAX	(64UL<<20)
-
 /*
  * Console mode. Override with conmode=
  */
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index f45b2ab0cb81..d7658c4b2ed5 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -95,7 +95,7 @@ static void *elfcorehdr_newmem;
 /*
  * Copy one page from zfcpdump "oldmem"
  *
- * For pages below ZFCPDUMP_HSA_SIZE memory from the HSA is copied. Otherwise
+ * For pages below HSA size memory from the HSA is copied. Otherwise
  * real memory copy is used.
  */
 static ssize_t copy_oldmem_page_zfcpdump(char *buf, size_t csize,
@@ -103,7 +103,7 @@ static ssize_t copy_oldmem_page_zfcpdump(char *buf, size_t csize,
 {
 	int rc;
 
-	if (src < ZFCPDUMP_HSA_SIZE) {
+	if (src < sclp_get_hsa_size()) {
 		rc = memcpy_hsa(buf, src, csize, userbuf);
 	} else {
 		if (userbuf)
@@ -188,18 +188,19 @@ static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma,
 /*
  * Remap "oldmem" for zfcpdump
  *
- * We only map available memory above ZFCPDUMP_HSA_SIZE. Memory below
- * ZFCPDUMP_HSA_SIZE is read on demand using the copy_oldmem_page() function.
+ * We only map available memory above HSA size. Memory below HSA size
+ * is read on demand using the copy_oldmem_page() function.
  */
 static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma,
 					   unsigned long from,
 					   unsigned long pfn,
 					   unsigned long size, pgprot_t prot)
 {
+	unsigned long hsa_end = sclp_get_hsa_size();
 	unsigned long size_hsa;
 
-	if (pfn < ZFCPDUMP_HSA_SIZE >> PAGE_SHIFT) {
-		size_hsa = min(size, ZFCPDUMP_HSA_SIZE - (pfn << PAGE_SHIFT));
+	if (pfn < hsa_end >> PAGE_SHIFT) {
+		size_hsa = min(size, hsa_end - (pfn << PAGE_SHIFT));
 		if (size == size_hsa)
 			return 0;
 		size -= size_hsa;
@@ -238,9 +239,9 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
 				return rc;
 		}
 	} else {
-		if ((unsigned long) src < ZFCPDUMP_HSA_SIZE) {
-			copied = min(count,
-				     ZFCPDUMP_HSA_SIZE - (unsigned long) src);
+		unsigned long hsa_end = sclp_get_hsa_size();
+		if ((unsigned long) src < hsa_end) {
+			copied = min(count, hsa_end - (unsigned long) src);
 			rc = memcpy_hsa(dest, (unsigned long) src, copied, 0);
 			if (rc)
 				return rc;
@@ -580,6 +581,9 @@ int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
 	/* If elfcorehdr= has been passed via cmdline, we use that one */
 	if (elfcorehdr_addr != ELFCORE_ADDR_MAX)
 		return 0;
+	/* If we cannot get HSA size for zfcpdump return error */
+	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !sclp_get_hsa_size())
+		return -ENODEV;
 	mem_chunk_cnt = get_mem_chunk_cnt();
 
 	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 96543ac400a7..c0462f45cf1b 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -484,6 +484,7 @@ void __init startup_init(void)
 	detect_machine_facilities();
 	setup_topology();
 	sclp_facilities_detect();
+	sclp_hsa_size_detect();
 #ifdef CONFIG_DYNAMIC_FTRACE
 	S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
 #endif
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index ffe1c53264a7..4444875266ee 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -471,8 +471,9 @@ static void __init setup_memory_end(void)
 
 
 #ifdef CONFIG_ZFCPDUMP
-	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
-		memory_end = ZFCPDUMP_HSA_SIZE;
+	if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
+	    !OLDMEM_BASE && sclp_get_hsa_size()) {
+		memory_end = sclp_get_hsa_size();
 		memory_end_set = 1;
 	}
 #endif
@@ -586,7 +587,7 @@ static unsigned long __init find_crash_base(unsigned long crash_size,
 		crash_base = (chunk->addr + chunk->size) - crash_size;
 		if (crash_base < crash_size)
 			continue;
-		if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
+		if (crash_base < sclp_get_hsa_size())
 			continue;
 		if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 			continue;