1 files changed, 179 insertions, 40 deletions

diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index d8f355657171..c84f33d51f7b 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -16,6 +16,7 @@
 #include <asm/os_info.h>
 #include <asm/elf.h>
 #include <asm/ipl.h>
+#include <asm/sclp.h>
 
 #define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
 #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
@@ -64,22 +65,46 @@ static ssize_t copy_page_real(void *buf, void *src, size_t csize)
 }
 
 /*
- * Copy one page from "oldmem"
+ * Pointer to ELF header in new kernel
+ */
+static void *elfcorehdr_newmem;
+
+/*
+ * Copy one page from zfcpdump "oldmem"
+ *
+ * For pages below ZFCPDUMP_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,
+					 unsigned long src, int userbuf)
+{
+	int rc;
+
+	if (src < ZFCPDUMP_HSA_SIZE) {
+		rc = memcpy_hsa(buf, src, csize, userbuf);
+	} else {
+		if (userbuf)
+			rc = copy_to_user_real((void __force __user *) buf,
+					       (void *) src, csize);
+		else
+			rc = memcpy_real(buf, (void *) src, csize);
+	}
+	return rc ? rc : csize;
+}
+
+/*
+ * Copy one page from kdump "oldmem"
  *
  * For the kdump reserved memory this functions performs a swap operation:
  *  - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
  *  - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
  */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-			 size_t csize, unsigned long offset, int userbuf)
+static ssize_t copy_oldmem_page_kdump(char *buf, size_t csize,
+				      unsigned long src, int userbuf)
+
 {
-	unsigned long src;
 	int rc;
 
-	if (!csize)
-		return 0;
-
-	src = (pfn << PAGE_SHIFT) + offset;
 	if (src < OLDMEM_SIZE)
 		src += OLDMEM_BASE;
 	else if (src > OLDMEM_BASE &&
@@ -90,7 +115,88 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
 				       (void *) src, csize);
 	else
 		rc = copy_page_real(buf, (void *) src, csize);
-	return (rc == 0) ? csize : rc;
+	return (rc == 0) ? rc : csize;
+}
+
+/*
+ * Copy one page from "oldmem"
+ */
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+			 unsigned long offset, int userbuf)
+{
+	unsigned long src;
+
+	if (!csize)
+		return 0;
+	src = (pfn << PAGE_SHIFT) + offset;
+	if (OLDMEM_BASE)
+		return copy_oldmem_page_kdump(buf, csize, src, userbuf);
+	else
+		return copy_oldmem_page_zfcpdump(buf, csize, src, userbuf);
+}
+
+/*
+ * Remap "oldmem" for kdump
+ *
+ * For the kdump reserved memory this functions performs a swap operation:
+ * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
+ */
+static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma,
+					unsigned long from, unsigned long pfn,
+					unsigned long size, pgprot_t prot)
+{
+	unsigned long size_old;
+	int rc;
+
+	if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) {
+		size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT));
+		rc = remap_pfn_range(vma, from,
+				     pfn + (OLDMEM_BASE >> PAGE_SHIFT),
+				     size_old, prot);
+		if (rc || size == size_old)
+			return rc;
+		size -= size_old;
+		from += size_old;
+		pfn += size_old >> PAGE_SHIFT;
+	}
+	return remap_pfn_range(vma, from, pfn, size, prot);
+}
+
+/*
+ * 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.
+ */
+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 size_hsa;
+
+	if (pfn < ZFCPDUMP_HSA_SIZE >> PAGE_SHIFT) {
+		size_hsa = min(size, ZFCPDUMP_HSA_SIZE - (pfn << PAGE_SHIFT));
+		if (size == size_hsa)
+			return 0;
+		size -= size_hsa;
+		from += size_hsa;
+		pfn += size_hsa >> PAGE_SHIFT;
+	}
+	return remap_pfn_range(vma, from, pfn, size, prot);
+}
+
+/*
+ * Remap "oldmem" for kdump or zfcpdump
+ */
+int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
+			   unsigned long pfn, unsigned long size, pgprot_t prot)
+{
+	if (OLDMEM_BASE)
+		return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot);
+	else
+		return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size,
+						       prot);
 }
 
 /*
@@ -101,11 +207,21 @@ int copy_from_oldmem(void *dest, void *src, size_t count)
 	unsigned long copied = 0;
 	int rc;
 
-	if ((unsigned long) src < OLDMEM_SIZE) {
-		copied = min(count, OLDMEM_SIZE - (unsigned long) src);
-		rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
-		if (rc)
-			return rc;
+	if (OLDMEM_BASE) {
+		if ((unsigned long) src < OLDMEM_SIZE) {
+			copied = min(count, OLDMEM_SIZE - (unsigned long) src);
+			rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
+			if (rc)
+				return rc;
+		}
+	} else {
+		if ((unsigned long) src < ZFCPDUMP_HSA_SIZE) {
+			copied = min(count,
+				     ZFCPDUMP_HSA_SIZE - (unsigned long) src);
+			rc = memcpy_hsa(dest, (unsigned long) src, copied, 0);
+			if (rc)
+				return rc;
+		}
 	}
 	return memcpy_real(dest + copied, src + copied, count - copied);
 }
@@ -368,14 +484,6 @@ static int get_mem_chunk_cnt(void)
 }
 
 /*
- * Relocate pointer in order to allow vmcore code access the data
- */
-static inline unsigned long relocate(unsigned long addr)
-{
-	return OLDMEM_BASE + addr;
-}
-
-/*
  * Initialize ELF loads (new kernel)
  */
 static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
@@ -426,7 +534,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
 	ptr = nt_vmcoreinfo(ptr);
 	memset(phdr, 0, sizeof(*phdr));
 	phdr->p_type = PT_NOTE;
-	phdr->p_offset = relocate(notes_offset);
+	phdr->p_offset = notes_offset;
 	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
 	phdr->p_memsz = phdr->p_filesz;
 	return ptr;
@@ -435,7 +543,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
 /*
  * Create ELF core header (new kernel)
  */
-static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
+int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
 {
 	Elf64_Phdr *phdr_notes, *phdr_loads;
 	int mem_chunk_cnt;
@@ -443,6 +551,12 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
 	u32 alloc_size;
 	u64 hdr_off;
 
+	/* If we are not in kdump or zfcpdump mode return */
+	if (!OLDMEM_BASE && ipl_info.type != IPL_TYPE_FCP_DUMP)
+		return 0;
+	/* If elfcorehdr= has been passed via cmdline, we use that one */
+	if (elfcorehdr_addr != ELFCORE_ADDR_MAX)
+		return 0;
 	mem_chunk_cnt = get_mem_chunk_cnt();
 
 	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
@@ -460,27 +574,52 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
 	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
 	/* Init loads */
 	hdr_off = PTR_DIFF(ptr, hdr);
-	loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off);
-	*elfcorebuf_sz = hdr_off;
-	*elfcorebuf = (void *) relocate((unsigned long) hdr);
-	BUG_ON(*elfcorebuf_sz > alloc_size);
+	loads_init(phdr_loads, hdr_off);
+	*addr = (unsigned long long) hdr;
+	elfcorehdr_newmem = hdr;
+	*size = (unsigned long long) hdr_off;
+	BUG_ON(elfcorehdr_size > alloc_size);
+	return 0;
 }
 
 /*
- * Create kdump ELF core header in new kernel, if it has not been passed via
- * the "elfcorehdr" kernel parameter
+ * Free ELF core header (new kernel)
  */
-static int setup_kdump_elfcorehdr(void)
+void elfcorehdr_free(unsigned long long addr)
 {
-	size_t elfcorebuf_sz;
-	char *elfcorebuf;
+	if (!elfcorehdr_newmem)
+		return;
+	kfree((void *)(unsigned long)addr);
+}
 
-	if (!OLDMEM_BASE || is_kdump_kernel())
-		return -EINVAL;
-	s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
-	elfcorehdr_addr = (unsigned long long) elfcorebuf;
-	elfcorehdr_size = elfcorebuf_sz;
-	return 0;
+/*
+ * Read from ELF header
+ */
+ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
+{
+	void *src = (void *)(unsigned long)*ppos;
+
+	src = elfcorehdr_newmem ? src : src - OLDMEM_BASE;
+	memcpy(buf, src, count);
+	*ppos += count;
+	return count;
 }
 
-subsys_initcall(setup_kdump_elfcorehdr);
+/*
+ * Read from ELF notes data
+ */
+ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
+{
+	void *src = (void *)(unsigned long)*ppos;
+	int rc;
+
+	if (elfcorehdr_newmem) {
+		memcpy(buf, src, count);
+	} else {
+		rc = copy_from_oldmem(buf, src, count);
+		if (rc)
+			return rc;
+	}
+	*ppos += count;
+	return count;
+}