/* * 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, 2008 * Author(s): Michael Holzheu */ #define KMSG_COMPONENT "zdump" #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include <linux/init.h> #include <linux/slab.h> #include <linux/miscdevice.h> #include <linux/debugfs.h> #include <linux/module.h> #include <linux/memblock.h> #include <asm/asm-offsets.h> #include <asm/ipl.h> #include <asm/sclp.h> #include <asm/setup.h> #include <asm/uaccess.h> #include <asm/debug.h> #include <asm/processor.h> #include <asm/irqflags.h> #include <asm/checksum.h> #include <asm/switch_to.h> #include "sclp.h" #define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x) #define TO_USER 1 #define TO_KERNEL 0 #define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */ 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; struct save_area lc_mask; }; struct ipib_info { unsigned long ipib; u32 checksum; } __attribute__((packed)); 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; static struct dentry *zcore_memmap_file; static struct dentry *zcore_reipl_file; static struct dentry *zcore_hsa_file; static struct ipl_parameter_block *ipl_block; /* * 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 */ 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 (!hsa_available) return -ENODATA; 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, count - offs)) 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 __init init_cpu_info(enum arch_id arch) { struct save_area_ext *sa_ext; /* get info for boot cpu from lowcore, stored in the HSA */ sa_ext = dump_save_areas.areas[0]; if (!sa_ext) return -ENOMEM; if (memcpy_hsa_kernel(&sa_ext->sa, sys_info.sa_base, sys_info.sa_size) < 0) { TRACE("could not copy from HSA\n"); kfree(sa_ext); return -EIO; } if (MACHINE_HAS_VX) save_vx_regs_safe(sa_ext->vx_regs); return 0; } static DEFINE_MUTEX(zcore_mutex); #define DUMP_VERSION 0x5 #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; struct cpuid cpu_id; u32 arch_id; u32 volnr; u32 build_arch; u64 rmem_size; u8 mvdump; u16 cpu_cnt; u16 real_cpu_cnt; u8 end_pad1[0x200-0x061]; u64 mvdump_sign; u64 mvdump_zipl_time; u8 end_pad2[0x800-0x210]; u32 lc_vec[512]; } __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, .build_arch = DUMP_ARCH_S390X, }; /* * 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; if (count == 0) return 0; end = start + count; for (i = 0; i < dump_save_areas.count; 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; struct save_area *save_area = &dump_save_areas.areas[i]->sa; prefix = save_area->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)) continue; 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, save_area, sa_off, len)) return -EFAULT; } return 0; } /* * Release the HSA */ static void release_hsa(void) { diag308(DIAG308_REL_HSA, NULL); hsa_available = 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 < sclp.hsa_size + HEADER_SIZE) { size = min((count - hdr_count), (size_t) (sclp.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 = copy_to_user_real(buf + hdr_count + mem_offs, (void *) 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) { if (hsa_available) release_hsa(); 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 const struct file_operations zcore_fops = { .owner = THIS_MODULE, .llseek = zcore_lseek, .read = zcore_read, .open = zcore_open, .release = zcore_release, }; static ssize_t zcore_memmap_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { return simple_read_from_buffer(buf, count, ppos, filp->private_data, memblock.memory.cnt * CHUNK_INFO_SIZE); } static int zcore_memmap_open(struct inode *inode, struct file *filp) { struct memblock_region *reg; char *buf; int i = 0; buf = kzalloc(memblock.memory.cnt * CHUNK_INFO_SIZE, GFP_KERNEL); if (!buf) { return -ENOMEM; } for_each_memblock(memory, reg) { sprintf(buf + (i++ * CHUNK_INFO_SIZE), "%016llx %016llx ", (unsigned long long) reg->base, (unsigned long long) reg->size); } filp->private_data = buf; return nonseekable_open(inode, filp); } static int zcore_memmap_release(struct inode *inode, struct file *filp) { kfree(filp->private_data); return 0; } static const struct file_operations zcore_memmap_fops = { .owner = THIS_MODULE, .read = zcore_memmap_read, .open = zcore_memmap_open, .release = zcore_memmap_release, .llseek = no_llseek, }; static ssize_t zcore_reipl_write(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { if (ipl_block) { diag308(DIAG308_SET, ipl_block); diag308(DIAG308_IPL, NULL); } return count; } static int zcore_reipl_open(struct inode *inode, struct file *filp) { return nonseekable_open(inode, filp); } static int zcore_reipl_release(struct inode *inode, struct file *filp) { return 0; } static const struct file_operations zcore_reipl_fops = { .owner = THIS_MODULE, .write = zcore_reipl_write, .open = zcore_reipl_open, .release = zcore_reipl_release, .llseek = no_llseek, }; static ssize_t zcore_hsa_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { static char str[18]; if (hsa_available) snprintf(str, sizeof(str), "%lx\n", sclp.hsa_size); else snprintf(str, sizeof(str), "0\n"); return simple_read_from_buffer(buf, count, ppos, str, strlen(str)); } static ssize_t zcore_hsa_write(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) { char value; if (*ppos != 0) return -EPIPE; if (copy_from_user(&value, buf, 1)) return -EFAULT; if (value != '0') return -EINVAL; release_hsa(); return count; } static const struct file_operations zcore_hsa_fops = { .owner = THIS_MODULE, .write = zcore_hsa_write, .read = zcore_hsa_read, .open = nonseekable_open, .llseek = no_llseek, }; static void __init set_lc_mask(struct save_area *map) { memset(&map->fp_regs, 0xff, sizeof(map->fp_regs)); memset(&map->gp_regs, 0xff, sizeof(map->gp_regs)); memset(&map->psw, 0xff, sizeof(map->psw)); memset(&map->pref_reg, 0xff, sizeof(map->pref_reg)); memset(&map->fp_ctrl_reg, 0xff, sizeof(map->fp_ctrl_reg)); memset(&map->tod_reg, 0xff, sizeof(map->tod_reg)); memset(&map->timer, 0xff, sizeof(map->timer)); memset(&map->clk_cmp, 0xff, sizeof(map->clk_cmp)); memset(&map->acc_regs, 0xff, sizeof(map->acc_regs)); memset(&map->ctrl_regs, 0xff, sizeof(map->ctrl_regs)); } /* * Initialize dump globals for a given architecture */ static int __init sys_info_init(enum arch_id arch, unsigned long mem_end) { int rc; switch (arch) { case ARCH_S390X: pr_alert("DETECTED 'S390X (64 bit) OS'\n"); break; case ARCH_S390: pr_alert("DETECTED 'S390 (32 bit) OS'\n"); break; default: pr_alert("0x%x is an unknown architecture.\n",arch); return -EINVAL; } sys_info.sa_base = SAVE_AREA_BASE; sys_info.sa_size = sizeof(struct save_area); sys_info.arch = arch; set_lc_mask(&sys_info.lc_mask); rc = init_cpu_info(arch); if (rc) return rc; sys_info.mem_size = mem_end; return 0; } static int __init check_sdias(void) { if (!sclp.hsa_size) { TRACE("Could not determine HSA size\n"); return -ENODEV; } return 0; } static int __init get_mem_info(unsigned long *mem, unsigned long *end) { struct memblock_region *reg; for_each_memblock(memory, reg) { *mem += reg->size; *end = max_t(unsigned long, *end, reg->base + reg->size); } return 0; } static void __init zcore_header_init(int arch, struct zcore_header *hdr, unsigned long mem_size) { u32 prefix; int i; if (arch == ARCH_S390X) hdr->arch_id = DUMP_ARCH_S390X; else hdr->arch_id = DUMP_ARCH_S390; hdr->mem_size = mem_size; hdr->rmem_size = mem_size; hdr->mem_end = sys_info.mem_size; hdr->num_pages = mem_size / PAGE_SIZE; hdr->tod = get_tod_clock(); get_cpu_id(&hdr->cpu_id); for (i = 0; i < dump_save_areas.count; i++) { prefix = dump_save_areas.areas[i]->sa.pref_reg; hdr->real_cpu_cnt++; if (!prefix) continue; hdr->lc_vec[hdr->cpu_cnt] = prefix; hdr->cpu_cnt++; } } /* * Provide IPL parameter information block from either HSA or memory * for future reipl */ static int __init zcore_reipl_init(void) { struct ipib_info ipib_info; int rc; rc = memcpy_hsa_kernel(&ipib_info, __LC_DUMP_REIPL, sizeof(ipib_info)); if (rc) return rc; if (ipib_info.ipib == 0) return 0; ipl_block = (void *) __get_free_page(GFP_KERNEL); if (!ipl_block) return -ENOMEM; if (ipib_info.ipib < sclp.hsa_size) rc = memcpy_hsa_kernel(ipl_block, ipib_info.ipib, PAGE_SIZE); else rc = memcpy_real(ipl_block, (void *) ipib_info.ipib, PAGE_SIZE); if (rc || csum_partial(ipl_block, ipl_block->hdr.len, 0) != ipib_info.checksum) { TRACE("Checksum does not match\n"); free_page((unsigned long) ipl_block); ipl_block = NULL; } return 0; } static int __init zcore_init(void) { unsigned long mem_size, mem_end; unsigned char arch; int rc; mem_size = mem_end = 0; if (ipl_info.type != IPL_TYPE_FCP_DUMP) return -ENODATA; if (OLDMEM_BASE) 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 = sclp_sdias_init(); if (rc) goto fail; rc = check_sdias(); if (rc) goto fail; hsa_available = 1; rc = memcpy_hsa_kernel(&arch, __LC_AR_MODE_ID, 1); if (rc) goto fail; if (arch == ARCH_S390) { pr_alert("The 64-bit dump tool cannot be used for a " "32-bit system\n"); rc = -EINVAL; goto fail; } rc = get_mem_info(&mem_size, &mem_end); if (rc) goto fail; rc = sys_info_init(arch, mem_end); if (rc) goto fail; zcore_header_init(arch, &zcore_header, mem_size); rc = zcore_reipl_init(); if (rc) goto fail; 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) { rc = -ENOMEM; goto fail_dir; } zcore_memmap_file = debugfs_create_file("memmap", S_IRUSR, zcore_dir, NULL, &zcore_memmap_fops); if (!zcore_memmap_file) { rc = -ENOMEM; goto fail_file; } zcore_reipl_file = debugfs_create_file("reipl", S_IRUSR, zcore_dir, NULL, &zcore_reipl_fops); if (!zcore_reipl_file) { rc = -ENOMEM; goto fail_memmap_file; } zcore_hsa_file = debugfs_create_file("hsa", S_IRUSR|S_IWUSR, zcore_dir, NULL, &zcore_hsa_fops); if (!zcore_hsa_file) { rc = -ENOMEM; goto fail_reipl_file; } return 0; fail_reipl_file: debugfs_remove(zcore_reipl_file); fail_memmap_file: debugfs_remove(zcore_memmap_file); fail_file: debugfs_remove(zcore_file); fail_dir: debugfs_remove(zcore_dir); fail: diag308(DIAG308_REL_HSA, NULL); return rc; } static void __exit zcore_exit(void) { debug_unregister(zcore_dbf); sclp_sdias_exit(); free_page((unsigned long) ipl_block); debugfs_remove(zcore_hsa_file); debugfs_remove(zcore_reipl_file); debugfs_remove(zcore_memmap_file); debugfs_remove(zcore_file); debugfs_remove(zcore_dir); diag308(DIAG308_REL_HSA, NULL); } MODULE_AUTHOR("Copyright IBM Corp. 2003,2008"); MODULE_DESCRIPTION("zcore module for zfcpdump support"); MODULE_LICENSE("GPL"); subsys_initcall(zcore_init); module_exit(zcore_exit);