diff options
Diffstat (limited to 'kernel/drivers/s390/char/zcore.c')
| -rw-r--r-- | kernel/drivers/s390/char/zcore.c | 750 |
1 files changed, 750 insertions, 0 deletions
diff --git a/kernel/drivers/s390/char/zcore.c b/kernel/drivers/s390/char/zcore.c new file mode 100644 index 000000000..a68fcfd1d --- /dev/null +++ b/kernel/drivers/s390/char/zcore.c @@ -0,0 +1,750 @@ +/* + * 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_area_create(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_get_hsa_size() + HEADER_SIZE) { + size = min((count - hdr_count), + (size_t) (sclp_get_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_get_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_get_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_get_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); |