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
13 #define KMSG_COMPONENT "zdump"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/debugfs.h>
19 #include <linux/memblock.h>
21 #include <asm/asm-offsets.h>
24 #include <asm/setup.h>
25 #include <linux/uaccess.h>
26 #include <asm/debug.h>
27 #include <asm/processor.h>
28 #include <asm/irqflags.h>
29 #include <asm/checksum.h>
30 #include <asm/os_info.h>
31 #include <asm/switch_to.h>
34 #define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x)
36 #define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */
46 } __attribute__((packed));
48 static struct debug_info *zcore_dbf;
49 static int hsa_available;
50 static struct dentry *zcore_dir;
51 static struct dentry *zcore_memmap_file;
52 static struct dentry *zcore_reipl_file;
53 static struct dentry *zcore_hsa_file;
54 static struct ipl_parameter_block *ipl_block;
56 static DEFINE_MUTEX(hsa_buf_mutex);
57 static char hsa_buf[PAGE_SIZE] __aligned(PAGE_SIZE);
60 * Copy memory from HSA to user memory (not reentrant):
62 * @dest: User buffer where memory should be copied to
63 * @src: Start address within HSA where data should be copied
64 * @count: Size of buffer, which should be copied
66 int memcpy_hsa_user(void __user *dest, unsigned long src, size_t count)
68 unsigned long offset, bytes;
73 mutex_lock(&hsa_buf_mutex);
75 if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) {
76 TRACE("sclp_sdias_copy() failed\n");
77 mutex_unlock(&hsa_buf_mutex);
80 offset = src % PAGE_SIZE;
81 bytes = min(PAGE_SIZE - offset, count);
82 if (copy_to_user(dest, hsa_buf + offset, bytes)) {
83 mutex_unlock(&hsa_buf_mutex);
90 mutex_unlock(&hsa_buf_mutex);
95 * Copy memory from HSA to kernel memory (not reentrant):
97 * @dest: Kernel or user buffer where memory should be copied to
98 * @src: Start address within HSA where data should be copied
99 * @count: Size of buffer, which should be copied
101 int memcpy_hsa_kernel(void *dest, unsigned long src, size_t count)
103 unsigned long offset, bytes;
108 mutex_lock(&hsa_buf_mutex);
110 if (sclp_sdias_copy(hsa_buf, src / PAGE_SIZE + 2, 1)) {
111 TRACE("sclp_sdias_copy() failed\n");
112 mutex_unlock(&hsa_buf_mutex);
115 offset = src % PAGE_SIZE;
116 bytes = min(PAGE_SIZE - offset, count);
117 memcpy(dest, hsa_buf + offset, bytes);
122 mutex_unlock(&hsa_buf_mutex);
126 static int __init init_cpu_info(void)
128 struct save_area *sa;
130 /* get info for boot cpu from lowcore, stored in the HSA */
131 sa = save_area_boot_cpu();
134 if (memcpy_hsa_kernel(hsa_buf, __LC_FPREGS_SAVE_AREA, 512) < 0) {
135 TRACE("could not copy from HSA\n");
138 save_area_add_regs(sa, hsa_buf); /* vx registers are saved in smp.c */
145 static void release_hsa(void)
147 diag308(DIAG308_REL_HSA, NULL);
151 static ssize_t zcore_memmap_read(struct file *filp, char __user *buf,
152 size_t count, loff_t *ppos)
154 return simple_read_from_buffer(buf, count, ppos, filp->private_data,
155 memblock.memory.cnt * CHUNK_INFO_SIZE);
158 static int zcore_memmap_open(struct inode *inode, struct file *filp)
160 struct memblock_region *reg;
164 buf = kzalloc(memblock.memory.cnt * CHUNK_INFO_SIZE, GFP_KERNEL);
168 for_each_memblock(memory, reg) {
169 sprintf(buf + (i++ * CHUNK_INFO_SIZE), "%016llx %016llx ",
170 (unsigned long long) reg->base,
171 (unsigned long long) reg->size);
173 filp->private_data = buf;
174 return nonseekable_open(inode, filp);
177 static int zcore_memmap_release(struct inode *inode, struct file *filp)
179 kfree(filp->private_data);
183 static const struct file_operations zcore_memmap_fops = {
184 .owner = THIS_MODULE,
185 .read = zcore_memmap_read,
186 .open = zcore_memmap_open,
187 .release = zcore_memmap_release,
191 static ssize_t zcore_reipl_write(struct file *filp, const char __user *buf,
192 size_t count, loff_t *ppos)
195 diag308(DIAG308_SET, ipl_block);
196 diag308(DIAG308_LOAD_CLEAR, NULL);
201 static int zcore_reipl_open(struct inode *inode, struct file *filp)
203 return nonseekable_open(inode, filp);
206 static int zcore_reipl_release(struct inode *inode, struct file *filp)
211 static const struct file_operations zcore_reipl_fops = {
212 .owner = THIS_MODULE,
213 .write = zcore_reipl_write,
214 .open = zcore_reipl_open,
215 .release = zcore_reipl_release,
219 static ssize_t zcore_hsa_read(struct file *filp, char __user *buf,
220 size_t count, loff_t *ppos)
225 snprintf(str, sizeof(str), "%lx\n", sclp.hsa_size);
227 snprintf(str, sizeof(str), "0\n");
228 return simple_read_from_buffer(buf, count, ppos, str, strlen(str));
231 static ssize_t zcore_hsa_write(struct file *filp, const char __user *buf,
232 size_t count, loff_t *ppos)
238 if (copy_from_user(&value, buf, 1))
246 static const struct file_operations zcore_hsa_fops = {
247 .owner = THIS_MODULE,
248 .write = zcore_hsa_write,
249 .read = zcore_hsa_read,
250 .open = nonseekable_open,
254 static int __init check_sdias(void)
256 if (!sclp.hsa_size) {
257 TRACE("Could not determine HSA size\n");
264 * Provide IPL parameter information block from either HSA or memory
267 static int __init zcore_reipl_init(void)
269 struct ipib_info ipib_info;
272 rc = memcpy_hsa_kernel(&ipib_info, __LC_DUMP_REIPL, sizeof(ipib_info));
275 if (ipib_info.ipib == 0)
277 ipl_block = (void *) __get_free_page(GFP_KERNEL);
280 if (ipib_info.ipib < sclp.hsa_size)
281 rc = memcpy_hsa_kernel(ipl_block, ipib_info.ipib, PAGE_SIZE);
283 rc = memcpy_real(ipl_block, (void *) ipib_info.ipib, PAGE_SIZE);
284 if (rc || (__force u32)csum_partial(ipl_block, ipl_block->hdr.len, 0) !=
285 ipib_info.checksum) {
286 TRACE("Checksum does not match\n");
287 free_page((unsigned long) ipl_block);
293 static int __init zcore_init(void)
298 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
303 zcore_dbf = debug_register("zcore", 4, 1, 4 * sizeof(long));
304 debug_register_view(zcore_dbf, &debug_sprintf_view);
305 debug_set_level(zcore_dbf, 6);
307 TRACE("devno: %x\n", ipl_info.data.fcp.dev_id.devno);
308 TRACE("wwpn: %llx\n", (unsigned long long) ipl_info.data.fcp.wwpn);
309 TRACE("lun: %llx\n", (unsigned long long) ipl_info.data.fcp.lun);
311 rc = sclp_sdias_init();
320 rc = memcpy_hsa_kernel(&arch, __LC_AR_MODE_ID, 1);
324 if (arch == ARCH_S390) {
325 pr_alert("The 64-bit dump tool cannot be used for a "
331 pr_alert("The dump process started for a 64-bit operating system\n");
332 rc = init_cpu_info();
336 rc = zcore_reipl_init();
340 zcore_dir = debugfs_create_dir("zcore" , NULL);
345 zcore_memmap_file = debugfs_create_file("memmap", S_IRUSR, zcore_dir,
346 NULL, &zcore_memmap_fops);
347 if (!zcore_memmap_file) {
351 zcore_reipl_file = debugfs_create_file("reipl", S_IRUSR, zcore_dir,
352 NULL, &zcore_reipl_fops);
353 if (!zcore_reipl_file) {
355 goto fail_memmap_file;
357 zcore_hsa_file = debugfs_create_file("hsa", S_IRUSR|S_IWUSR, zcore_dir,
358 NULL, &zcore_hsa_fops);
359 if (!zcore_hsa_file) {
361 goto fail_reipl_file;
366 debugfs_remove(zcore_reipl_file);
368 debugfs_remove(zcore_memmap_file);
370 debugfs_remove(zcore_dir);
372 diag308(DIAG308_REL_HSA, NULL);
375 subsys_initcall(zcore_init);