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-rw-r--r--arch/s390/kernel/crash_dump.c292
1 files changed, 229 insertions, 63 deletions
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index d8f35565717..d7658c4b2ed 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -16,11 +16,38 @@
#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)))
#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))
+struct dump_save_areas dump_save_areas;
+
+/*
+ * Allocate and add a save area for a CPU
+ */
+struct save_area *dump_save_area_create(int cpu)
+{
+ struct save_area **save_areas, *save_area;
+
+ save_area = kmalloc(sizeof(*save_area), GFP_KERNEL);
+ if (!save_area)
+ return NULL;
+ if (cpu + 1 > dump_save_areas.count) {
+ dump_save_areas.count = cpu + 1;
+ save_areas = krealloc(dump_save_areas.areas,
+ dump_save_areas.count * sizeof(void *),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!save_areas) {
+ kfree(save_area);
+ return NULL;
+ }
+ dump_save_areas.areas = save_areas;
+ }
+ dump_save_areas.areas[cpu] = save_area;
+ return save_area;
+}
/*
* Return physical address for virtual address
@@ -39,47 +66,68 @@ static inline void *load_real_addr(void *addr)
}
/*
- * Copy up to one page to vmalloc or real memory
+ * Copy real to virtual or real memory
*/
-static ssize_t copy_page_real(void *buf, void *src, size_t csize)
+static int copy_from_realmem(void *dest, void *src, size_t count)
{
- size_t size;
+ unsigned long size;
- if (is_vmalloc_addr(buf)) {
- BUG_ON(csize >= PAGE_SIZE);
- /* If buf is not page aligned, copy first part */
- size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize);
- if (size) {
- if (memcpy_real(load_real_addr(buf), src, size))
- return -EFAULT;
- buf += size;
- src += size;
- }
- /* Copy second part */
- size = csize - size;
- return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0;
+ if (!count)
+ return 0;
+ if (!is_vmalloc_or_module_addr(dest))
+ return memcpy_real(dest, src, count);
+ do {
+ size = min(count, PAGE_SIZE - (__pa(dest) & ~PAGE_MASK));
+ if (memcpy_real(load_real_addr(dest), src, size))
+ return -EFAULT;
+ count -= size;
+ dest += size;
+ src += size;
+ } while (count);
+ return 0;
+}
+
+/*
+ * Pointer to ELF header in new kernel
+ */
+static void *elfcorehdr_newmem;
+
+/*
+ * Copy one page from zfcpdump "oldmem"
+ *
+ * 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,
+ unsigned long src, int userbuf)
+{
+ int rc;
+
+ if (src < sclp_get_hsa_size()) {
+ rc = memcpy_hsa(buf, src, csize, userbuf);
} else {
- return memcpy_real(buf, src, csize);
+ 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 "oldmem"
+ * 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 &&
@@ -89,8 +137,90 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
rc = copy_to_user_real((void __force __user *) buf,
(void *) src, csize);
else
- rc = copy_page_real(buf, (void *) src, csize);
- return (rc == 0) ? csize : rc;
+ rc = copy_from_realmem(buf, (void *) src, csize);
+ 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 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 < hsa_end >> PAGE_SHIFT) {
+ size_hsa = min(size, hsa_end - (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);
}
/*
@@ -101,13 +231,23 @@ 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 = copy_from_realmem(dest, src + OLDMEM_BASE, copied);
+ if (rc)
+ return rc;
+ }
+ } else {
+ 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;
+ }
}
- return memcpy_real(dest + copied, src + copied, count - copied);
+ return copy_from_realmem(dest + copied, src + copied, count - copied);
}
/*
@@ -337,8 +477,8 @@ static int get_cpu_cnt(void)
{
int i, cpus = 0;
- for (i = 0; zfcpdump_save_areas[i]; i++) {
- if (zfcpdump_save_areas[i]->pref_reg == 0)
+ for (i = 0; i < dump_save_areas.count; i++) {
+ if (dump_save_areas.areas[i]->pref_reg == 0)
continue;
cpus++;
}
@@ -368,14 +508,6 @@ 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)
@@ -417,8 +549,8 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
ptr = nt_prpsinfo(ptr);
- for (i = 0; zfcpdump_save_areas[i]; i++) {
- sa = zfcpdump_save_areas[i];
+ for (i = 0; i < dump_save_areas.count; i++) {
+ sa = dump_save_areas.areas[i];
if (sa->pref_reg == 0)
continue;
ptr = fill_cpu_elf_notes(ptr, sa);
@@ -426,7 +558,7 @@ 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 +567,7 @@ 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 +575,15 @@ 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;
+ /* 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 +
@@ -460,27 +601,52 @@ 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;
+}