diff options
Diffstat (limited to 'drivers/s390/char/zcore.c')
| -rw-r--r-- | drivers/s390/char/zcore.c | 651 |
1 files changed, 651 insertions, 0 deletions
diff --git a/drivers/s390/char/zcore.c b/drivers/s390/char/zcore.c new file mode 100644 index 000000000000..89d439316a53 --- /dev/null +++ b/drivers/s390/char/zcore.c @@ -0,0 +1,651 @@ +/* + * zcore module to export memory content and register sets for creating system + * dumps on SCSI disks (zfcpdump). The "zcore/mem" debugfs file shows the same + * dump format as s390 standalone dumps. + * + * For more information please refer to Documentation/s390/zfcpdump.txt + * + * Copyright IBM Corp. 2003,2007 + * Author(s): Michael Holzheu + */ + +#include <linux/init.h> +#include <linux/miscdevice.h> +#include <linux/utsname.h> +#include <linux/debugfs.h> +#include <asm/ipl.h> +#include <asm/sclp.h> +#include <asm/setup.h> +#include <asm/sigp.h> +#include <asm/uaccess.h> +#include <asm/debug.h> +#include <asm/processor.h> +#include <asm/irqflags.h> + +#define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x) +#define MSG(x...) printk( KERN_ALERT x ) +#define ERROR_MSG(x...) printk ( KERN_ALERT "DUMP: " x ) + +#define TO_USER 0 +#define TO_KERNEL 1 + +enum arch_id { + ARCH_S390 = 0, + ARCH_S390X = 1, +}; + +/* dump system info */ + +struct sys_info { + enum arch_id arch; + unsigned long sa_base; + u32 sa_size; + int cpu_map[NR_CPUS]; + unsigned long mem_size; + union save_area lc_mask; +}; + +static struct sys_info sys_info; +static struct debug_info *zcore_dbf; +static int hsa_available; +static struct dentry *zcore_dir; +static struct dentry *zcore_file; + +/* + * Copy memory from HSA to kernel or user memory (not reentrant): + * + * @dest: Kernel or user buffer where memory should be copied to + * @src: Start address within HSA where data should be copied + * @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 offs, blk_num; + static char buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); + + if (count == 0) + return 0; + + /* copy first block */ + offs = 0; + if ((src % PAGE_SIZE) != 0) { + blk_num = src / PAGE_SIZE + 2; + if (sclp_sdias_copy(buf, blk_num, 1)) { + TRACE("sclp_sdias_copy() failed\n"); + return -EIO; + } + offs = min((PAGE_SIZE - (src % PAGE_SIZE)), count); + if (mode == TO_USER) { + if (copy_to_user((__force __user void*) dest, + buf + (src % PAGE_SIZE), offs)) + return -EFAULT; + } else + memcpy(dest, buf + (src % PAGE_SIZE), offs); + } + if (offs == count) + goto out; + + /* copy middle */ + for (; (offs + PAGE_SIZE) <= count; offs += PAGE_SIZE) { + blk_num = (src + offs) / PAGE_SIZE + 2; + if (sclp_sdias_copy(buf, blk_num, 1)) { + TRACE("sclp_sdias_copy() failed\n"); + return -EIO; + } + if (mode == TO_USER) { + if (copy_to_user((__force __user void*) dest + offs, + buf, PAGE_SIZE)) + return -EFAULT; + } else + memcpy(dest + offs, buf, PAGE_SIZE); + } + if (offs == count) + goto out; + + /* copy last block */ + blk_num = (src + offs) / PAGE_SIZE + 2; + if (sclp_sdias_copy(buf, blk_num, 1)) { + TRACE("sclp_sdias_copy() failed\n"); + return -EIO; + } + if (mode == TO_USER) { + if (copy_to_user((__force __user void*) dest + offs, buf, + PAGE_SIZE)) + return -EFAULT; + } else + memcpy(dest + offs, buf, count - offs); +out: + return 0; +} + +static int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count) +{ + return memcpy_hsa((void __force *) dest, src, count, TO_USER); +} + +static int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count) +{ + return memcpy_hsa(dest, src, count, TO_KERNEL); +} + +static int memcpy_real(void *dest, unsigned long src, size_t count) +{ + unsigned long flags; + int rc = -EFAULT; + register unsigned long _dest asm("2") = (unsigned long) dest; + register unsigned long _len1 asm("3") = (unsigned long) count; + register unsigned long _src asm("4") = src; + register unsigned long _len2 asm("5") = (unsigned long) count; + + if (count == 0) + return 0; + flags = __raw_local_irq_stnsm(0xf8); /* switch to real mode */ + asm volatile ( + "0: mvcle %1,%2,0x0\n" + "1: jo 0b\n" + " lhi %0,0x0\n" + "2:\n" + EX_TABLE(1b,2b) + : "+d" (rc) + : "d" (_dest), "d" (_src), "d" (_len1), "d" (_len2) + : "cc", "memory"); + __raw_local_irq_ssm(flags); + + return rc; +} + +static int memcpy_real_user(__user void *dest, unsigned long src, size_t count) +{ + static char buf[4096]; + int offs = 0, size; + + while (offs < count) { + size = min(sizeof(buf), count - offs); + if (memcpy_real(buf, src + offs, size)) + return -EFAULT; + if (copy_to_user(dest + offs, buf, size)) + return -EFAULT; + offs += size; + } + return 0; +} + +#ifdef __s390x__ +/* + * Convert s390x (64 bit) cpu info to s390 (32 bit) cpu info + */ +static void __init s390x_to_s390_regs(union save_area *out, union save_area *in, + int cpu) +{ + int i; + + for (i = 0; i < 16; i++) { + out->s390.gp_regs[i] = in->s390x.gp_regs[i] & 0x00000000ffffffff; + out->s390.acc_regs[i] = in->s390x.acc_regs[i]; + out->s390.ctrl_regs[i] = + in->s390x.ctrl_regs[i] & 0x00000000ffffffff; + } + /* locore for 31 bit has only space for fpregs 0,2,4,6 */ + out->s390.fp_regs[0] = in->s390x.fp_regs[0]; + out->s390.fp_regs[1] = in->s390x.fp_regs[2]; + out->s390.fp_regs[2] = in->s390x.fp_regs[4]; + out->s390.fp_regs[3] = in->s390x.fp_regs[6]; + memcpy(&(out->s390.psw[0]), &(in->s390x.psw[0]), 4); + out->s390.psw[1] |= 0x8; /* set bit 12 */ + memcpy(&(out->s390.psw[4]),&(in->s390x.psw[12]), 4); + out->s390.psw[4] |= 0x80; /* set (31bit) addressing bit */ + out->s390.pref_reg = in->s390x.pref_reg; + out->s390.timer = in->s390x.timer; + out->s390.clk_cmp = in->s390x.clk_cmp; +} + +static void __init s390x_to_s390_save_areas(void) +{ + int i = 1; + static union save_area tmp; + + while (zfcpdump_save_areas[i]) { + s390x_to_s390_regs(&tmp, zfcpdump_save_areas[i], i); + memcpy(zfcpdump_save_areas[i], &tmp, sizeof(tmp)); + i++; + } +} + +#endif /* __s390x__ */ + +static int __init init_cpu_info(enum arch_id arch) +{ + union save_area *sa; + + /* get info for boot cpu from lowcore, stored in the HSA */ + + sa = kmalloc(sizeof(*sa), GFP_KERNEL); + if (!sa) { + ERROR_MSG("kmalloc failed: %s: %i\n",__FUNCTION__, __LINE__); + return -ENOMEM; + } + if (memcpy_hsa_kernel(sa, sys_info.sa_base, sys_info.sa_size) < 0) { + ERROR_MSG("could not copy from HSA\n"); + kfree(sa); + return -EIO; + } + zfcpdump_save_areas[0] = sa; + +#ifdef __s390x__ + /* convert s390x regs to s390, if we are dumping an s390 Linux */ + + if (arch == ARCH_S390) + s390x_to_s390_save_areas(); +#endif + + return 0; +} + +static DEFINE_MUTEX(zcore_mutex); + +#define DUMP_VERSION 0x3 +#define DUMP_MAGIC 0xa8190173618f23fdULL +#define DUMP_ARCH_S390X 2 +#define DUMP_ARCH_S390 1 +#define HEADER_SIZE 4096 + +/* dump header dumped according to s390 crash dump format */ + +struct zcore_header { + u64 magic; + u32 version; + u32 header_size; + u32 dump_level; + u32 page_size; + u64 mem_size; + u64 mem_start; + u64 mem_end; + u32 num_pages; + u32 pad1; + u64 tod; + cpuid_t cpu_id; + u32 arch_id; + u32 build_arch; + char pad2[4016]; +} __attribute__((packed,__aligned__(16))); + +static struct zcore_header zcore_header = { + .magic = DUMP_MAGIC, + .version = DUMP_VERSION, + .header_size = 4096, + .dump_level = 0, + .page_size = PAGE_SIZE, + .mem_start = 0, +#ifdef __s390x__ + .build_arch = DUMP_ARCH_S390X, +#else + .build_arch = DUMP_ARCH_S390, +#endif +}; + +/* + * Copy lowcore info to buffer. Use map in order to copy only register parts. + * + * @buf: User buffer + * @sa: Pointer to save area + * @sa_off: Offset in save area to copy + * @len: Number of bytes to copy + */ +static int copy_lc(void __user *buf, void *sa, int sa_off, int len) +{ + int i; + char *lc_mask = (char*)&sys_info.lc_mask; + + for (i = 0; i < len; i++) { + if (!lc_mask[i + sa_off]) + continue; + if (copy_to_user(buf + i, sa + sa_off + i, 1)) + return -EFAULT; + } + return 0; +} + +/* + * Copy lowcores info to memory, if necessary + * + * @buf: User buffer + * @addr: Start address of buffer in dump memory + * @count: Size of buffer + */ +static int zcore_add_lc(char __user *buf, unsigned long start, size_t count) +{ + unsigned long end; + int i = 0; + + if (count == 0) + return 0; + + end = start + count; + while (zfcpdump_save_areas[i]) { + unsigned long cp_start, cp_end; /* copy range */ + unsigned long sa_start, sa_end; /* save area range */ + unsigned long prefix; + unsigned long sa_off, len, buf_off; + + if (sys_info.arch == ARCH_S390) + prefix = zfcpdump_save_areas[i]->s390.pref_reg; + else + prefix = zfcpdump_save_areas[i]->s390x.pref_reg; + + sa_start = prefix + sys_info.sa_base; + sa_end = prefix + sys_info.sa_base + sys_info.sa_size; + + if ((end < sa_start) || (start > sa_end)) + goto next; + cp_start = max(start, sa_start); + cp_end = min(end, sa_end); + + buf_off = cp_start - start; + sa_off = cp_start - sa_start; + len = cp_end - cp_start; + + TRACE("copy_lc for: %lx\n", start); + if (copy_lc(buf + buf_off, zfcpdump_save_areas[i], sa_off, len)) + return -EFAULT; +next: + i++; + } + return 0; +} + +/* + * Read routine for zcore character device + * First 4K are dump header + * Next 32MB are HSA Memory + * Rest is read from absolute Memory + */ +static ssize_t zcore_read(struct file *file, char __user *buf, size_t count, + loff_t *ppos) +{ + unsigned long mem_start; /* Start address in memory */ + size_t mem_offs; /* Offset in dump memory */ + size_t hdr_count; /* Size of header part of output buffer */ + size_t size; + int rc; + + mutex_lock(&zcore_mutex); + + if (*ppos > (sys_info.mem_size + HEADER_SIZE)) { + rc = -EINVAL; + goto fail; + } + + count = min(count, (size_t) (sys_info.mem_size + HEADER_SIZE - *ppos)); + + /* Copy dump header */ + if (*ppos < HEADER_SIZE) { + size = min(count, (size_t) (HEADER_SIZE - *ppos)); + if (copy_to_user(buf, &zcore_header + *ppos, size)) { + rc = -EFAULT; + goto fail; + } + hdr_count = size; + mem_start = 0; + } else { + hdr_count = 0; + mem_start = *ppos - HEADER_SIZE; + } + + mem_offs = 0; + + /* Copy from HSA data */ + if (*ppos < (ZFCPDUMP_HSA_SIZE + HEADER_SIZE)) { + size = min((count - hdr_count), (size_t) (ZFCPDUMP_HSA_SIZE + - mem_start)); + rc = memcpy_hsa_user(buf + hdr_count, mem_start, size); + if (rc) + goto fail; + + mem_offs += size; + } + + /* Copy from real mem */ + size = count - mem_offs - hdr_count; + rc = memcpy_real_user(buf + hdr_count + mem_offs, mem_start + mem_offs, + size); + if (rc) + goto fail; + + /* + * Since s390 dump analysis tools like lcrash or crash + * expect register sets in the prefix pages of the cpus, + * we copy them into the read buffer, if necessary. + * buf + hdr_count: Start of memory part of output buffer + * mem_start: Start memory address to copy from + * count - hdr_count: Size of memory area to copy + */ + if (zcore_add_lc(buf + hdr_count, mem_start, count - hdr_count)) { + rc = -EFAULT; + goto fail; + } + *ppos += count; +fail: + mutex_unlock(&zcore_mutex); + return (rc < 0) ? rc : count; +} + +static int zcore_open(struct inode *inode, struct file *filp) +{ + if (!hsa_available) + return -ENODATA; + else + return capable(CAP_SYS_RAWIO) ? 0 : -EPERM; +} + +static int zcore_release(struct inode *inode, struct file *filep) +{ + diag308(DIAG308_REL_HSA, NULL); + hsa_available = 0; + return 0; +} + +static loff_t zcore_lseek(struct file *file, loff_t offset, int orig) +{ + loff_t rc; + + mutex_lock(&zcore_mutex); + switch (orig) { + case 0: + file->f_pos = offset; + rc = file->f_pos; + break; + case 1: + file->f_pos += offset; + rc = file->f_pos; + break; + default: + rc = -EINVAL; + } + mutex_unlock(&zcore_mutex); + return rc; +} + +static struct file_operations zcore_fops = { + .owner = THIS_MODULE, + .llseek = zcore_lseek, + .read = zcore_read, + .open = zcore_open, + .release = zcore_release, +}; + + +static void __init set_s390_lc_mask(union save_area *map) +{ + memset(&map->s390.ext_save, 0xff, sizeof(map->s390.ext_save)); + memset(&map->s390.timer, 0xff, sizeof(map->s390.timer)); + memset(&map->s390.clk_cmp, 0xff, sizeof(map->s390.clk_cmp)); + memset(&map->s390.psw, 0xff, sizeof(map->s390.psw)); + memset(&map->s390.pref_reg, 0xff, sizeof(map->s390.pref_reg)); + memset(&map->s390.acc_regs, 0xff, sizeof(map->s390.acc_regs)); + memset(&map->s390.fp_regs, 0xff, sizeof(map->s390.fp_regs)); + memset(&map->s390.gp_regs, 0xff, sizeof(map->s390.gp_regs)); + memset(&map->s390.ctrl_regs, 0xff, sizeof(map->s390.ctrl_regs)); +} + +static void __init set_s390x_lc_mask(union save_area *map) +{ + memset(&map->s390x.fp_regs, 0xff, sizeof(map->s390x.fp_regs)); + memset(&map->s390x.gp_regs, 0xff, sizeof(map->s390x.gp_regs)); + memset(&map->s390x.psw, 0xff, sizeof(map->s390x.psw)); + memset(&map->s390x.pref_reg, 0xff, sizeof(map->s390x.pref_reg)); + memset(&map->s390x.fp_ctrl_reg, 0xff, sizeof(map->s390x.fp_ctrl_reg)); + memset(&map->s390x.tod_reg, 0xff, sizeof(map->s390x.tod_reg)); + memset(&map->s390x.timer, 0xff, sizeof(map->s390x.timer)); + memset(&map->s390x.clk_cmp, 0xff, sizeof(map->s390x.clk_cmp)); + memset(&map->s390x.acc_regs, 0xff, sizeof(map->s390x.acc_regs)); + memset(&map->s390x.ctrl_regs, 0xff, sizeof(map->s390x.ctrl_regs)); +} + +/* + * Initialize dump globals for a given architecture + */ +static int __init sys_info_init(enum arch_id arch) +{ + switch (arch) { + case ARCH_S390X: + MSG("DETECTED 'S390X (64 bit) OS'\n"); + sys_info.sa_base = SAVE_AREA_BASE_S390X; + sys_info.sa_size = sizeof(struct save_area_s390x); + set_s390x_lc_mask(&sys_info.lc_mask); + break; + case ARCH_S390: + MSG("DETECTED 'S390 (32 bit) OS'\n"); + sys_info.sa_base = SAVE_AREA_BASE_S390; + sys_info.sa_size = sizeof(struct save_area_s390); + set_s390_lc_mask(&sys_info.lc_mask); + break; + default: + ERROR_MSG("unknown architecture 0x%x.\n",arch); + return -EINVAL; + } + sys_info.arch = arch; + if (init_cpu_info(arch)) { + ERROR_MSG("get cpu info failed\n"); + return -ENOMEM; + } + sys_info.mem_size = real_memory_size; + + return 0; +} + +static int __init check_sdias(void) +{ + int rc, act_hsa_size; + + rc = sclp_sdias_blk_count(); + if (rc < 0) { + ERROR_MSG("Could not determine HSA size\n"); + return rc; + } + act_hsa_size = (rc - 1) * PAGE_SIZE; + if (act_hsa_size < ZFCPDUMP_HSA_SIZE) { + ERROR_MSG("HSA size too small: %i\n", act_hsa_size); + return -EINVAL; + } + return 0; +} + +static void __init zcore_header_init(int arch, struct zcore_header *hdr) +{ + if (arch == ARCH_S390X) + hdr->arch_id = DUMP_ARCH_S390X; + else + hdr->arch_id = DUMP_ARCH_S390; + hdr->mem_size = sys_info.mem_size; + hdr->mem_end = sys_info.mem_size; + hdr->num_pages = sys_info.mem_size / PAGE_SIZE; + hdr->tod = get_clock(); + get_cpu_id(&hdr->cpu_id); +} + +extern int sdias_init(void); + +static int __init zcore_init(void) +{ + unsigned char arch; + int rc; + + if (ipl_info.type != IPL_TYPE_FCP_DUMP) + return -ENODATA; + + zcore_dbf = debug_register("zcore", 4, 1, 4 * sizeof(long)); + debug_register_view(zcore_dbf, &debug_sprintf_view); + debug_set_level(zcore_dbf, 6); + + TRACE("devno: %x\n", ipl_info.data.fcp.dev_id.devno); + TRACE("wwpn: %llx\n", (unsigned long long) ipl_info.data.fcp.wwpn); + TRACE("lun: %llx\n", (unsigned long long) ipl_info.data.fcp.lun); + + rc = sdias_init(); + if (rc) + goto fail; + + rc = check_sdias(); + if (rc) { + ERROR_MSG("Dump initialization failed\n"); + goto fail; + } + + rc = memcpy_hsa_kernel(&arch, __LC_AR_MODE_ID, 1); + if (rc) { + ERROR_MSG("sdial memcpy for arch id failed\n"); + goto fail; + } + +#ifndef __s390x__ + if (arch == ARCH_S390X) { + ERROR_MSG("32 bit dumper can't dump 64 bit system!\n"); + rc = -EINVAL; + goto fail; + } +#endif + + rc = sys_info_init(arch); + if (rc) { + ERROR_MSG("arch init failed\n"); + goto fail; + } + + zcore_header_init(arch, &zcore_header); + + zcore_dir = debugfs_create_dir("zcore" , NULL); + if (!zcore_dir) { + rc = -ENOMEM; + goto fail; + } + zcore_file = debugfs_create_file("mem", S_IRUSR, zcore_dir, NULL, + &zcore_fops); + if (!zcore_file) { + debugfs_remove(zcore_dir); + rc = -ENOMEM; + goto fail; + } + hsa_available = 1; + return 0; + +fail: + diag308(DIAG308_REL_HSA, NULL); + return rc; +} + +extern void sdias_exit(void); + +static void __exit zcore_exit(void) +{ + debug_unregister(zcore_dbf); + sdias_exit(); + diag308(DIAG308_REL_HSA, NULL); +} + +MODULE_AUTHOR("Copyright IBM Corp. 2003,2007"); +MODULE_DESCRIPTION("zcore module for zfcpdump support"); +MODULE_LICENSE("GPL"); + +subsys_initcall(zcore_init); +module_exit(zcore_exit); |