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path: root/drivers/s390/char/zcore.c
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Diffstat (limited to 'drivers/s390/char/zcore.c')
-rw-r--r--drivers/s390/char/zcore.c651
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);