From 6f79d33228fa7cf900826738a39f287cae96cd91 Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Wed, 11 Sep 2013 14:24:54 -0700 Subject: [PATCH] s390/vmcore: use vmcore for zfcpdump Modify the s390 copy_oldmem_page() and remap_oldmem_pfn_range() function for zfcpdump to read from the HSA memory if memory below HSA_SIZE bytes is requested. Otherwise real memory is used. Signed-off-by: Michael Holzheu Cc: HATAYAMA Daisuke Cc: Jan Willeke Cc: Vivek Goyal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/Kconfig | 3 +- arch/s390/include/asm/sclp.h | 1 + arch/s390/kernel/crash_dump.c | 122 +++++++++++++++++++++++++++++----- drivers/s390/char/zcore.c | 6 +- 4 files changed, 110 insertions(+), 22 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index fb2723e8ba65..3ec272859e1e 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -526,6 +526,7 @@ config CRASH_DUMP bool "kernel crash dumps" depends on 64BIT && SMP select KEXEC + select ZFCPDUMP help Generate crash dump after being started by kexec. Crash dump kernels are loaded in the main kernel with kexec-tools @@ -536,7 +537,7 @@ config CRASH_DUMP config ZFCPDUMP def_bool n prompt "zfcpdump support" - select SMP + depends on SMP help Select this option if you want to build an zfcpdump enabled kernel. Refer to for more details on this. diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h index 06a136136047..7dc7f9c63b65 100644 --- a/arch/s390/include/asm/sclp.h +++ b/arch/s390/include/asm/sclp.h @@ -56,5 +56,6 @@ bool sclp_has_linemode(void); 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); #endif /* _ASM_S390_SCLP_H */ diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 3e776158b330..c84f33d51f7b 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -16,6 +16,7 @@ #include #include #include +#include #define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y))) #define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y))) @@ -69,22 +70,41 @@ static ssize_t copy_page_real(void *buf, void *src, size_t csize) static void *elfcorehdr_newmem; /* - * Copy one page from "oldmem" + * 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 && @@ -95,17 +115,35 @@ 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; } /* - * Remap "oldmem" + * 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] */ -int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from, - unsigned long pfn, unsigned long size, pgprot_t prot) +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; @@ -124,6 +162,43 @@ int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from, 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); +} + /* * Copy memory from old kernel */ @@ -132,11 +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); } @@ -466,7 +551,8 @@ int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) u32 alloc_size; u64 hdr_off; - if (!OLDMEM_BASE) + /* 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) diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c index 9e5e14686e75..794820a123d0 100644 --- a/drivers/s390/char/zcore.c +++ b/drivers/s390/char/zcore.c @@ -30,8 +30,8 @@ #define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x) -#define TO_USER 0 -#define TO_KERNEL 1 +#define TO_USER 1 +#define TO_KERNEL 0 #define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */ enum arch_id { @@ -73,7 +73,7 @@ static struct ipl_parameter_block *ipl_block; * @count: Size of buffer, which should be copied * @mode: Either TO_KERNEL or TO_USER */ -static int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode) +int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode) { int offs, blk_num; static char buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); -- 2.30.2