2 * zcore module to export memory content and register sets for creating system
3 * dumps on SCSI disks (zfcpdump). The "zcore/mem" debugfs file shows the same
4 * dump format as s390 standalone dumps.
6 * For more information please refer to Documentation/s390/zfcpdump.txt
8 * Copyright IBM Corp. 2003, 2008
9 * Author(s): Michael Holzheu
12 #define KMSG_COMPONENT "zdump"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/miscdevice.h>
18 #include <linux/debugfs.h>
19 #include <linux/module.h>
20 #include <asm/asm-offsets.h>
23 #include <asm/setup.h>
24 #include <asm/uaccess.h>
25 #include <asm/debug.h>
26 #include <asm/processor.h>
27 #include <asm/irqflags.h>
28 #include <asm/checksum.h>
31 #define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x)
35 #define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */
42 /* dump system info */
46 unsigned long sa_base;
49 unsigned long mem_size;
50 struct save_area lc_mask;
56 } __attribute__((packed));
58 static struct sys_info sys_info;
59 static struct debug_info *zcore_dbf;
60 static int hsa_available;
61 static struct dentry *zcore_dir;
62 static struct dentry *zcore_file;
63 static struct dentry *zcore_memmap_file;
64 static struct dentry *zcore_reipl_file;
65 static struct dentry *zcore_hsa_file;
66 static struct ipl_parameter_block *ipl_block;
69 * Copy memory from HSA to kernel or user memory (not reentrant):
71 * @dest: Kernel or user buffer where memory should be copied to
72 * @src: Start address within HSA where data should be copied
73 * @count: Size of buffer, which should be copied
74 * @mode: Either TO_KERNEL or TO_USER
76 static int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode)
79 static char buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
86 /* copy first block */
88 if ((src % PAGE_SIZE) != 0) {
89 blk_num = src / PAGE_SIZE + 2;
90 if (sclp_sdias_copy(buf, blk_num, 1)) {
91 TRACE("sclp_sdias_copy() failed\n");
94 offs = min((PAGE_SIZE - (src % PAGE_SIZE)), count);
95 if (mode == TO_USER) {
96 if (copy_to_user((__force __user void*) dest,
97 buf + (src % PAGE_SIZE), offs))
100 memcpy(dest, buf + (src % PAGE_SIZE), offs);
106 for (; (offs + PAGE_SIZE) <= count; offs += PAGE_SIZE) {
107 blk_num = (src + offs) / PAGE_SIZE + 2;
108 if (sclp_sdias_copy(buf, blk_num, 1)) {
109 TRACE("sclp_sdias_copy() failed\n");
112 if (mode == TO_USER) {
113 if (copy_to_user((__force __user void*) dest + offs,
117 memcpy(dest + offs, buf, PAGE_SIZE);
122 /* copy last block */
123 blk_num = (src + offs) / PAGE_SIZE + 2;
124 if (sclp_sdias_copy(buf, blk_num, 1)) {
125 TRACE("sclp_sdias_copy() failed\n");
128 if (mode == TO_USER) {
129 if (copy_to_user((__force __user void*) dest + offs, buf,
133 memcpy(dest + offs, buf, count - offs);
138 static int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count)
140 return memcpy_hsa((void __force *) dest, src, count, TO_USER);
143 static int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count)
145 return memcpy_hsa(dest, src, count, TO_KERNEL);
148 static int __init init_cpu_info(enum arch_id arch)
150 struct save_area *sa;
152 /* get info for boot cpu from lowcore, stored in the HSA */
154 sa = kmalloc(sizeof(*sa), GFP_KERNEL);
157 if (memcpy_hsa_kernel(sa, sys_info.sa_base, sys_info.sa_size) < 0) {
158 TRACE("could not copy from HSA\n");
162 zfcpdump_save_areas[0] = sa;
166 static DEFINE_MUTEX(zcore_mutex);
168 #define DUMP_VERSION 0x5
169 #define DUMP_MAGIC 0xa8190173618f23fdULL
170 #define DUMP_ARCH_S390X 2
171 #define DUMP_ARCH_S390 1
172 #define HEADER_SIZE 4096
174 /* dump header dumped according to s390 crash dump format */
176 struct zcore_header {
196 u8 end_pad1[0x200-0x061];
198 u64 mvdump_zipl_time;
199 u8 end_pad2[0x800-0x210];
201 } __attribute__((packed,__aligned__(16)));
203 static struct zcore_header zcore_header = {
205 .version = DUMP_VERSION,
208 .page_size = PAGE_SIZE,
211 .build_arch = DUMP_ARCH_S390X,
213 .build_arch = DUMP_ARCH_S390,
218 * Copy lowcore info to buffer. Use map in order to copy only register parts.
221 * @sa: Pointer to save area
222 * @sa_off: Offset in save area to copy
223 * @len: Number of bytes to copy
225 static int copy_lc(void __user *buf, void *sa, int sa_off, int len)
228 char *lc_mask = (char*)&sys_info.lc_mask;
230 for (i = 0; i < len; i++) {
231 if (!lc_mask[i + sa_off])
233 if (copy_to_user(buf + i, sa + sa_off + i, 1))
240 * Copy lowcores info to memory, if necessary
243 * @addr: Start address of buffer in dump memory
244 * @count: Size of buffer
246 static int zcore_add_lc(char __user *buf, unsigned long start, size_t count)
255 while (zfcpdump_save_areas[i]) {
256 unsigned long cp_start, cp_end; /* copy range */
257 unsigned long sa_start, sa_end; /* save area range */
258 unsigned long prefix;
259 unsigned long sa_off, len, buf_off;
261 prefix = zfcpdump_save_areas[i]->pref_reg;
262 sa_start = prefix + sys_info.sa_base;
263 sa_end = prefix + sys_info.sa_base + sys_info.sa_size;
265 if ((end < sa_start) || (start > sa_end))
267 cp_start = max(start, sa_start);
268 cp_end = min(end, sa_end);
270 buf_off = cp_start - start;
271 sa_off = cp_start - sa_start;
272 len = cp_end - cp_start;
274 TRACE("copy_lc for: %lx\n", start);
275 if (copy_lc(buf + buf_off, zfcpdump_save_areas[i], sa_off, len))
286 static void release_hsa(void)
288 diag308(DIAG308_REL_HSA, NULL);
293 * Read routine for zcore character device
294 * First 4K are dump header
295 * Next 32MB are HSA Memory
296 * Rest is read from absolute Memory
298 static ssize_t zcore_read(struct file *file, char __user *buf, size_t count,
301 unsigned long mem_start; /* Start address in memory */
302 size_t mem_offs; /* Offset in dump memory */
303 size_t hdr_count; /* Size of header part of output buffer */
307 mutex_lock(&zcore_mutex);
309 if (*ppos > (sys_info.mem_size + HEADER_SIZE)) {
314 count = min(count, (size_t) (sys_info.mem_size + HEADER_SIZE - *ppos));
316 /* Copy dump header */
317 if (*ppos < HEADER_SIZE) {
318 size = min(count, (size_t) (HEADER_SIZE - *ppos));
319 if (copy_to_user(buf, &zcore_header + *ppos, size)) {
327 mem_start = *ppos - HEADER_SIZE;
332 /* Copy from HSA data */
333 if (*ppos < (ZFCPDUMP_HSA_SIZE + HEADER_SIZE)) {
334 size = min((count - hdr_count), (size_t) (ZFCPDUMP_HSA_SIZE
336 rc = memcpy_hsa_user(buf + hdr_count, mem_start, size);
343 /* Copy from real mem */
344 size = count - mem_offs - hdr_count;
345 rc = copy_to_user_real(buf + hdr_count + mem_offs,
346 (void *) mem_start + mem_offs, size);
351 * Since s390 dump analysis tools like lcrash or crash
352 * expect register sets in the prefix pages of the cpus,
353 * we copy them into the read buffer, if necessary.
354 * buf + hdr_count: Start of memory part of output buffer
355 * mem_start: Start memory address to copy from
356 * count - hdr_count: Size of memory area to copy
358 if (zcore_add_lc(buf + hdr_count, mem_start, count - hdr_count)) {
364 mutex_unlock(&zcore_mutex);
365 return (rc < 0) ? rc : count;
368 static int zcore_open(struct inode *inode, struct file *filp)
373 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
376 static int zcore_release(struct inode *inode, struct file *filep)
383 static loff_t zcore_lseek(struct file *file, loff_t offset, int orig)
387 mutex_lock(&zcore_mutex);
390 file->f_pos = offset;
394 file->f_pos += offset;
400 mutex_unlock(&zcore_mutex);
404 static const struct file_operations zcore_fops = {
405 .owner = THIS_MODULE,
406 .llseek = zcore_lseek,
409 .release = zcore_release,
412 static ssize_t zcore_memmap_read(struct file *filp, char __user *buf,
413 size_t count, loff_t *ppos)
415 return simple_read_from_buffer(buf, count, ppos, filp->private_data,
416 MEMORY_CHUNKS * CHUNK_INFO_SIZE);
419 static int zcore_memmap_open(struct inode *inode, struct file *filp)
423 struct mem_chunk *chunk_array;
425 chunk_array = kzalloc(MEMORY_CHUNKS * sizeof(struct mem_chunk),
429 detect_memory_layout(chunk_array, 0);
430 buf = kzalloc(MEMORY_CHUNKS * CHUNK_INFO_SIZE, GFP_KERNEL);
435 for (i = 0; i < MEMORY_CHUNKS; i++) {
436 sprintf(buf + (i * CHUNK_INFO_SIZE), "%016llx %016llx ",
437 (unsigned long long) chunk_array[i].addr,
438 (unsigned long long) chunk_array[i].size);
439 if (chunk_array[i].size == 0)
443 filp->private_data = buf;
444 return nonseekable_open(inode, filp);
447 static int zcore_memmap_release(struct inode *inode, struct file *filp)
449 kfree(filp->private_data);
453 static const struct file_operations zcore_memmap_fops = {
454 .owner = THIS_MODULE,
455 .read = zcore_memmap_read,
456 .open = zcore_memmap_open,
457 .release = zcore_memmap_release,
461 static ssize_t zcore_reipl_write(struct file *filp, const char __user *buf,
462 size_t count, loff_t *ppos)
465 diag308(DIAG308_SET, ipl_block);
466 diag308(DIAG308_IPL, NULL);
471 static int zcore_reipl_open(struct inode *inode, struct file *filp)
473 return nonseekable_open(inode, filp);
476 static int zcore_reipl_release(struct inode *inode, struct file *filp)
481 static const struct file_operations zcore_reipl_fops = {
482 .owner = THIS_MODULE,
483 .write = zcore_reipl_write,
484 .open = zcore_reipl_open,
485 .release = zcore_reipl_release,
489 static ssize_t zcore_hsa_read(struct file *filp, char __user *buf,
490 size_t count, loff_t *ppos)
495 snprintf(str, sizeof(str), "%lx\n", ZFCPDUMP_HSA_SIZE);
497 snprintf(str, sizeof(str), "0\n");
498 return simple_read_from_buffer(buf, count, ppos, str, strlen(str));
501 static ssize_t zcore_hsa_write(struct file *filp, const char __user *buf,
502 size_t count, loff_t *ppos)
508 if (copy_from_user(&value, buf, 1))
516 static const struct file_operations zcore_hsa_fops = {
517 .owner = THIS_MODULE,
518 .write = zcore_hsa_write,
519 .read = zcore_hsa_read,
520 .open = nonseekable_open,
526 static void __init set_lc_mask(struct save_area *map)
528 memset(&map->ext_save, 0xff, sizeof(map->ext_save));
529 memset(&map->timer, 0xff, sizeof(map->timer));
530 memset(&map->clk_cmp, 0xff, sizeof(map->clk_cmp));
531 memset(&map->psw, 0xff, sizeof(map->psw));
532 memset(&map->pref_reg, 0xff, sizeof(map->pref_reg));
533 memset(&map->acc_regs, 0xff, sizeof(map->acc_regs));
534 memset(&map->fp_regs, 0xff, sizeof(map->fp_regs));
535 memset(&map->gp_regs, 0xff, sizeof(map->gp_regs));
536 memset(&map->ctrl_regs, 0xff, sizeof(map->ctrl_regs));
539 #else /* CONFIG_32BIT */
541 static void __init set_lc_mask(struct save_area *map)
543 memset(&map->fp_regs, 0xff, sizeof(map->fp_regs));
544 memset(&map->gp_regs, 0xff, sizeof(map->gp_regs));
545 memset(&map->psw, 0xff, sizeof(map->psw));
546 memset(&map->pref_reg, 0xff, sizeof(map->pref_reg));
547 memset(&map->fp_ctrl_reg, 0xff, sizeof(map->fp_ctrl_reg));
548 memset(&map->tod_reg, 0xff, sizeof(map->tod_reg));
549 memset(&map->timer, 0xff, sizeof(map->timer));
550 memset(&map->clk_cmp, 0xff, sizeof(map->clk_cmp));
551 memset(&map->acc_regs, 0xff, sizeof(map->acc_regs));
552 memset(&map->ctrl_regs, 0xff, sizeof(map->ctrl_regs));
555 #endif /* CONFIG_32BIT */
558 * Initialize dump globals for a given architecture
560 static int __init sys_info_init(enum arch_id arch, unsigned long mem_end)
566 pr_alert("DETECTED 'S390X (64 bit) OS'\n");
569 pr_alert("DETECTED 'S390 (32 bit) OS'\n");
572 pr_alert("0x%x is an unknown architecture.\n",arch);
575 sys_info.sa_base = SAVE_AREA_BASE;
576 sys_info.sa_size = sizeof(struct save_area);
577 sys_info.arch = arch;
578 set_lc_mask(&sys_info.lc_mask);
579 rc = init_cpu_info(arch);
582 sys_info.mem_size = mem_end;
587 static int __init check_sdias(void)
589 int rc, act_hsa_size;
591 rc = sclp_sdias_blk_count();
593 TRACE("Could not determine HSA size\n");
596 act_hsa_size = (rc - 1) * PAGE_SIZE;
597 if (act_hsa_size < ZFCPDUMP_HSA_SIZE) {
598 TRACE("HSA size too small: %i\n", act_hsa_size);
604 static int __init get_mem_info(unsigned long *mem, unsigned long *end)
607 struct mem_chunk *chunk_array;
609 chunk_array = kzalloc(MEMORY_CHUNKS * sizeof(struct mem_chunk),
613 detect_memory_layout(chunk_array, 0);
614 for (i = 0; i < MEMORY_CHUNKS; i++) {
615 if (chunk_array[i].size == 0)
617 *mem += chunk_array[i].size;
618 *end = max(*end, chunk_array[i].addr + chunk_array[i].size);
624 static void __init zcore_header_init(int arch, struct zcore_header *hdr,
625 unsigned long mem_size)
630 if (arch == ARCH_S390X)
631 hdr->arch_id = DUMP_ARCH_S390X;
633 hdr->arch_id = DUMP_ARCH_S390;
634 hdr->mem_size = mem_size;
635 hdr->rmem_size = mem_size;
636 hdr->mem_end = sys_info.mem_size;
637 hdr->num_pages = mem_size / PAGE_SIZE;
638 hdr->tod = get_tod_clock();
639 get_cpu_id(&hdr->cpu_id);
640 for (i = 0; zfcpdump_save_areas[i]; i++) {
641 prefix = zfcpdump_save_areas[i]->pref_reg;
645 hdr->lc_vec[hdr->cpu_cnt] = prefix;
651 * Provide IPL parameter information block from either HSA or memory
654 static int __init zcore_reipl_init(void)
656 struct ipib_info ipib_info;
659 rc = memcpy_hsa_kernel(&ipib_info, __LC_DUMP_REIPL, sizeof(ipib_info));
662 if (ipib_info.ipib == 0)
664 ipl_block = (void *) __get_free_page(GFP_KERNEL);
667 if (ipib_info.ipib < ZFCPDUMP_HSA_SIZE)
668 rc = memcpy_hsa_kernel(ipl_block, ipib_info.ipib, PAGE_SIZE);
670 rc = memcpy_real(ipl_block, (void *) ipib_info.ipib, PAGE_SIZE);
671 if (rc || csum_partial(ipl_block, ipl_block->hdr.len, 0) !=
672 ipib_info.checksum) {
673 TRACE("Checksum does not match\n");
674 free_page((unsigned long) ipl_block);
680 static int __init zcore_init(void)
682 unsigned long mem_size, mem_end;
686 mem_size = mem_end = 0;
687 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
692 zcore_dbf = debug_register("zcore", 4, 1, 4 * sizeof(long));
693 debug_register_view(zcore_dbf, &debug_sprintf_view);
694 debug_set_level(zcore_dbf, 6);
696 TRACE("devno: %x\n", ipl_info.data.fcp.dev_id.devno);
697 TRACE("wwpn: %llx\n", (unsigned long long) ipl_info.data.fcp.wwpn);
698 TRACE("lun: %llx\n", (unsigned long long) ipl_info.data.fcp.lun);
700 rc = sclp_sdias_init();
709 rc = memcpy_hsa_kernel(&arch, __LC_AR_MODE_ID, 1);
714 if (arch == ARCH_S390) {
715 pr_alert("The 64-bit dump tool cannot be used for a "
720 #else /* CONFIG_64BIT */
721 if (arch == ARCH_S390X) {
722 pr_alert("The 32-bit dump tool cannot be used for a "
727 #endif /* CONFIG_64BIT */
729 rc = get_mem_info(&mem_size, &mem_end);
733 rc = sys_info_init(arch, mem_end);
736 zcore_header_init(arch, &zcore_header, mem_size);
738 rc = zcore_reipl_init();
742 zcore_dir = debugfs_create_dir("zcore" , NULL);
747 zcore_file = debugfs_create_file("mem", S_IRUSR, zcore_dir, NULL,
753 zcore_memmap_file = debugfs_create_file("memmap", S_IRUSR, zcore_dir,
754 NULL, &zcore_memmap_fops);
755 if (!zcore_memmap_file) {
759 zcore_reipl_file = debugfs_create_file("reipl", S_IRUSR, zcore_dir,
760 NULL, &zcore_reipl_fops);
761 if (!zcore_reipl_file) {
763 goto fail_memmap_file;
765 zcore_hsa_file = debugfs_create_file("hsa", S_IRUSR|S_IWUSR, zcore_dir,
766 NULL, &zcore_hsa_fops);
767 if (!zcore_hsa_file) {
769 goto fail_reipl_file;
774 debugfs_remove(zcore_reipl_file);
776 debugfs_remove(zcore_memmap_file);
778 debugfs_remove(zcore_file);
780 debugfs_remove(zcore_dir);
782 diag308(DIAG308_REL_HSA, NULL);
786 static void __exit zcore_exit(void)
788 debug_unregister(zcore_dbf);
790 free_page((unsigned long) ipl_block);
791 debugfs_remove(zcore_hsa_file);
792 debugfs_remove(zcore_reipl_file);
793 debugfs_remove(zcore_memmap_file);
794 debugfs_remove(zcore_file);
795 debugfs_remove(zcore_dir);
796 diag308(DIAG308_REL_HSA, NULL);
799 MODULE_AUTHOR("Copyright IBM Corp. 2003,2008");
800 MODULE_DESCRIPTION("zcore module for zfcpdump support");
801 MODULE_LICENSE("GPL");
803 subsys_initcall(zcore_init);
804 module_exit(zcore_exit);