v4.19.13 snapshot.
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
new file mode 100644
index 0000000..d374f9b
--- /dev/null
+++ b/arch/s390/kernel/debug.c
@@ -0,0 +1,1460 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * S/390 debug facility
+ *
+ * Copyright IBM Corp. 1999, 2012
+ *
+ * Author(s): Michael Holzheu (holzheu@de.ibm.com),
+ * Holger Smolinski (Holger.Smolinski@de.ibm.com)
+ *
+ * Bugreports to: <Linux390@de.ibm.com>
+ */
+
+#define KMSG_COMPONENT "s390dbf"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/sysctl.h>
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+
+#include <asm/debug.h>
+
+#define DEBUG_PROLOG_ENTRY -1
+
+#define ALL_AREAS 0 /* copy all debug areas */
+#define NO_AREAS 1 /* copy no debug areas */
+
+/* typedefs */
+
+typedef struct file_private_info {
+ loff_t offset; /* offset of last read in file */
+ int act_area; /* number of last formated area */
+ int act_page; /* act page in given area */
+ int act_entry; /* last formated entry (offset */
+ /* relative to beginning of last */
+ /* formated page) */
+ size_t act_entry_offset; /* up to this offset we copied */
+ /* in last read the last formated */
+ /* entry to userland */
+ char temp_buf[2048]; /* buffer for output */
+ debug_info_t *debug_info_org; /* original debug information */
+ debug_info_t *debug_info_snap; /* snapshot of debug information */
+ struct debug_view *view; /* used view of debug info */
+} file_private_info_t;
+
+typedef struct {
+ char *string;
+ /*
+ * This assumes that all args are converted into longs
+ * on L/390 this is the case for all types of parameter
+ * except of floats, and long long (32 bit)
+ *
+ */
+ long args[0];
+} debug_sprintf_entry_t;
+
+/* internal function prototyes */
+
+static int debug_init(void);
+static ssize_t debug_output(struct file *file, char __user *user_buf,
+ size_t user_len, loff_t *offset);
+static ssize_t debug_input(struct file *file, const char __user *user_buf,
+ size_t user_len, loff_t *offset);
+static int debug_open(struct inode *inode, struct file *file);
+static int debug_close(struct inode *inode, struct file *file);
+static debug_info_t *debug_info_create(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, umode_t mode);
+static void debug_info_get(debug_info_t *);
+static void debug_info_put(debug_info_t *);
+static int debug_prolog_level_fn(debug_info_t *id,
+ struct debug_view *view, char *out_buf);
+static int debug_input_level_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_buf_size, loff_t *offset);
+static int debug_prolog_pages_fn(debug_info_t *id,
+ struct debug_view *view, char *out_buf);
+static int debug_input_pages_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_buf_size, loff_t *offset);
+static int debug_input_flush_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_buf_size, loff_t *offset);
+static int debug_hex_ascii_format_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf, const char *in_buf);
+static int debug_raw_format_fn(debug_info_t *id,
+ struct debug_view *view, char *out_buf,
+ const char *in_buf);
+static int debug_raw_header_fn(debug_info_t *id, struct debug_view *view,
+ int area, debug_entry_t *entry, char *out_buf);
+
+static int debug_sprintf_format_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf, debug_sprintf_entry_t *curr_event);
+
+/* globals */
+
+struct debug_view debug_raw_view = {
+ "raw",
+ NULL,
+ &debug_raw_header_fn,
+ &debug_raw_format_fn,
+ NULL,
+ NULL
+};
+EXPORT_SYMBOL(debug_raw_view);
+
+struct debug_view debug_hex_ascii_view = {
+ "hex_ascii",
+ NULL,
+ &debug_dflt_header_fn,
+ &debug_hex_ascii_format_fn,
+ NULL,
+ NULL
+};
+EXPORT_SYMBOL(debug_hex_ascii_view);
+
+static struct debug_view debug_level_view = {
+ "level",
+ &debug_prolog_level_fn,
+ NULL,
+ NULL,
+ &debug_input_level_fn,
+ NULL
+};
+
+static struct debug_view debug_pages_view = {
+ "pages",
+ &debug_prolog_pages_fn,
+ NULL,
+ NULL,
+ &debug_input_pages_fn,
+ NULL
+};
+
+static struct debug_view debug_flush_view = {
+ "flush",
+ NULL,
+ NULL,
+ NULL,
+ &debug_input_flush_fn,
+ NULL
+};
+
+struct debug_view debug_sprintf_view = {
+ "sprintf",
+ NULL,
+ &debug_dflt_header_fn,
+ (debug_format_proc_t *)&debug_sprintf_format_fn,
+ NULL,
+ NULL
+};
+EXPORT_SYMBOL(debug_sprintf_view);
+
+/* used by dump analysis tools to determine version of debug feature */
+static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION;
+
+/* static globals */
+
+static debug_info_t *debug_area_first;
+static debug_info_t *debug_area_last;
+static DEFINE_MUTEX(debug_mutex);
+
+static int initialized;
+static int debug_critical;
+
+static const struct file_operations debug_file_ops = {
+ .owner = THIS_MODULE,
+ .read = debug_output,
+ .write = debug_input,
+ .open = debug_open,
+ .release = debug_close,
+ .llseek = no_llseek,
+};
+
+static struct dentry *debug_debugfs_root_entry;
+
+/* functions */
+
+/*
+ * debug_areas_alloc
+ * - Debug areas are implemented as a threedimensonal array:
+ * areas[areanumber][pagenumber][pageoffset]
+ */
+
+static debug_entry_t ***debug_areas_alloc(int pages_per_area, int nr_areas)
+{
+ debug_entry_t ***areas;
+ int i, j;
+
+ areas = kmalloc_array(nr_areas, sizeof(debug_entry_t **), GFP_KERNEL);
+ if (!areas)
+ goto fail_malloc_areas;
+ for (i = 0; i < nr_areas; i++) {
+ areas[i] = kmalloc_array(pages_per_area,
+ sizeof(debug_entry_t *),
+ GFP_KERNEL);
+ if (!areas[i])
+ goto fail_malloc_areas2;
+ for (j = 0; j < pages_per_area; j++) {
+ areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!areas[i][j]) {
+ for (j--; j >= 0 ; j--)
+ kfree(areas[i][j]);
+ kfree(areas[i]);
+ goto fail_malloc_areas2;
+ }
+ }
+ }
+ return areas;
+
+fail_malloc_areas2:
+ for (i--; i >= 0; i--) {
+ for (j = 0; j < pages_per_area; j++)
+ kfree(areas[i][j]);
+ kfree(areas[i]);
+ }
+ kfree(areas);
+fail_malloc_areas:
+ return NULL;
+}
+
+/*
+ * debug_info_alloc
+ * - alloc new debug-info
+ */
+static debug_info_t *debug_info_alloc(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, int level,
+ int mode)
+{
+ debug_info_t *rc;
+
+ /* alloc everything */
+ rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
+ if (!rc)
+ goto fail_malloc_rc;
+ rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
+ if (!rc->active_entries)
+ goto fail_malloc_active_entries;
+ rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
+ if (!rc->active_pages)
+ goto fail_malloc_active_pages;
+ if ((mode == ALL_AREAS) && (pages_per_area != 0)) {
+ rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
+ if (!rc->areas)
+ goto fail_malloc_areas;
+ } else {
+ rc->areas = NULL;
+ }
+
+ /* initialize members */
+ spin_lock_init(&rc->lock);
+ rc->pages_per_area = pages_per_area;
+ rc->nr_areas = nr_areas;
+ rc->active_area = 0;
+ rc->level = level;
+ rc->buf_size = buf_size;
+ rc->entry_size = sizeof(debug_entry_t) + buf_size;
+ strlcpy(rc->name, name, sizeof(rc->name));
+ memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
+ memset(rc->debugfs_entries, 0, DEBUG_MAX_VIEWS * sizeof(struct dentry *));
+ refcount_set(&(rc->ref_count), 0);
+
+ return rc;
+
+fail_malloc_areas:
+ kfree(rc->active_pages);
+fail_malloc_active_pages:
+ kfree(rc->active_entries);
+fail_malloc_active_entries:
+ kfree(rc);
+fail_malloc_rc:
+ return NULL;
+}
+
+/*
+ * debug_areas_free
+ * - free all debug areas
+ */
+static void debug_areas_free(debug_info_t *db_info)
+{
+ int i, j;
+
+ if (!db_info->areas)
+ return;
+ for (i = 0; i < db_info->nr_areas; i++) {
+ for (j = 0; j < db_info->pages_per_area; j++)
+ kfree(db_info->areas[i][j]);
+ kfree(db_info->areas[i]);
+ }
+ kfree(db_info->areas);
+ db_info->areas = NULL;
+}
+
+/*
+ * debug_info_free
+ * - free memory debug-info
+ */
+static void debug_info_free(debug_info_t *db_info)
+{
+ debug_areas_free(db_info);
+ kfree(db_info->active_entries);
+ kfree(db_info->active_pages);
+ kfree(db_info);
+}
+
+/*
+ * debug_info_create
+ * - create new debug-info
+ */
+
+static debug_info_t *debug_info_create(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, umode_t mode)
+{
+ debug_info_t *rc;
+
+ rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
+ DEBUG_DEFAULT_LEVEL, ALL_AREAS);
+ if (!rc)
+ goto out;
+
+ rc->mode = mode & ~S_IFMT;
+
+ /* create root directory */
+ rc->debugfs_root_entry = debugfs_create_dir(rc->name,
+ debug_debugfs_root_entry);
+
+ /* append new element to linked list */
+ if (!debug_area_first) {
+ /* first element in list */
+ debug_area_first = rc;
+ rc->prev = NULL;
+ } else {
+ /* append element to end of list */
+ debug_area_last->next = rc;
+ rc->prev = debug_area_last;
+ }
+ debug_area_last = rc;
+ rc->next = NULL;
+
+ refcount_set(&rc->ref_count, 1);
+out:
+ return rc;
+}
+
+/*
+ * debug_info_copy
+ * - copy debug-info
+ */
+static debug_info_t *debug_info_copy(debug_info_t *in, int mode)
+{
+ unsigned long flags;
+ debug_info_t *rc;
+ int i, j;
+
+ /* get a consistent copy of the debug areas */
+ do {
+ rc = debug_info_alloc(in->name, in->pages_per_area,
+ in->nr_areas, in->buf_size, in->level, mode);
+ spin_lock_irqsave(&in->lock, flags);
+ if (!rc)
+ goto out;
+ /* has something changed in the meantime ? */
+ if ((rc->pages_per_area == in->pages_per_area) &&
+ (rc->nr_areas == in->nr_areas)) {
+ break;
+ }
+ spin_unlock_irqrestore(&in->lock, flags);
+ debug_info_free(rc);
+ } while (1);
+
+ if (mode == NO_AREAS)
+ goto out;
+
+ for (i = 0; i < in->nr_areas; i++) {
+ for (j = 0; j < in->pages_per_area; j++)
+ memcpy(rc->areas[i][j], in->areas[i][j], PAGE_SIZE);
+ }
+out:
+ spin_unlock_irqrestore(&in->lock, flags);
+ return rc;
+}
+
+/*
+ * debug_info_get
+ * - increments reference count for debug-info
+ */
+static void debug_info_get(debug_info_t *db_info)
+{
+ if (db_info)
+ refcount_inc(&db_info->ref_count);
+}
+
+/*
+ * debug_info_put:
+ * - decreases reference count for debug-info and frees it if necessary
+ */
+static void debug_info_put(debug_info_t *db_info)
+{
+ int i;
+
+ if (!db_info)
+ return;
+ if (refcount_dec_and_test(&db_info->ref_count)) {
+ for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+ if (!db_info->views[i])
+ continue;
+ debugfs_remove(db_info->debugfs_entries[i]);
+ }
+ debugfs_remove(db_info->debugfs_root_entry);
+ if (db_info == debug_area_first)
+ debug_area_first = db_info->next;
+ if (db_info == debug_area_last)
+ debug_area_last = db_info->prev;
+ if (db_info->prev)
+ db_info->prev->next = db_info->next;
+ if (db_info->next)
+ db_info->next->prev = db_info->prev;
+ debug_info_free(db_info);
+ }
+}
+
+/*
+ * debug_format_entry:
+ * - format one debug entry and return size of formated data
+ */
+static int debug_format_entry(file_private_info_t *p_info)
+{
+ debug_info_t *id_snap = p_info->debug_info_snap;
+ struct debug_view *view = p_info->view;
+ debug_entry_t *act_entry;
+ size_t len = 0;
+
+ if (p_info->act_entry == DEBUG_PROLOG_ENTRY) {
+ /* print prolog */
+ if (view->prolog_proc)
+ len += view->prolog_proc(id_snap, view, p_info->temp_buf);
+ goto out;
+ }
+ if (!id_snap->areas) /* this is true, if we have a prolog only view */
+ goto out; /* or if 'pages_per_area' is 0 */
+ act_entry = (debug_entry_t *) ((char *)id_snap->areas[p_info->act_area]
+ [p_info->act_page] + p_info->act_entry);
+
+ if (act_entry->id.stck == 0LL)
+ goto out; /* empty entry */
+ if (view->header_proc)
+ len += view->header_proc(id_snap, view, p_info->act_area,
+ act_entry, p_info->temp_buf + len);
+ if (view->format_proc)
+ len += view->format_proc(id_snap, view, p_info->temp_buf + len,
+ DEBUG_DATA(act_entry));
+out:
+ return len;
+}
+
+/*
+ * debug_next_entry:
+ * - goto next entry in p_info
+ */
+static inline int debug_next_entry(file_private_info_t *p_info)
+{
+ debug_info_t *id;
+
+ id = p_info->debug_info_snap;
+ if (p_info->act_entry == DEBUG_PROLOG_ENTRY) {
+ p_info->act_entry = 0;
+ p_info->act_page = 0;
+ goto out;
+ }
+ if (!id->areas)
+ return 1;
+ p_info->act_entry += id->entry_size;
+ /* switch to next page, if we reached the end of the page */
+ if (p_info->act_entry > (PAGE_SIZE - id->entry_size)) {
+ /* next page */
+ p_info->act_entry = 0;
+ p_info->act_page += 1;
+ if ((p_info->act_page % id->pages_per_area) == 0) {
+ /* next area */
+ p_info->act_area++;
+ p_info->act_page = 0;
+ }
+ if (p_info->act_area >= id->nr_areas)
+ return 1;
+ }
+out:
+ return 0;
+}
+
+/*
+ * debug_output:
+ * - called for user read()
+ * - copies formated debug entries to the user buffer
+ */
+static ssize_t debug_output(struct file *file, /* file descriptor */
+ char __user *user_buf, /* user buffer */
+ size_t len, /* length of buffer */
+ loff_t *offset) /* offset in the file */
+{
+ size_t count = 0;
+ size_t entry_offset;
+ file_private_info_t *p_info;
+
+ p_info = (file_private_info_t *) file->private_data;
+ if (*offset != p_info->offset)
+ return -EPIPE;
+ if (p_info->act_area >= p_info->debug_info_snap->nr_areas)
+ return 0;
+ entry_offset = p_info->act_entry_offset;
+ while (count < len) {
+ int formatted_line_residue;
+ int formatted_line_size;
+ int user_buf_residue;
+ size_t copy_size;
+
+ formatted_line_size = debug_format_entry(p_info);
+ formatted_line_residue = formatted_line_size - entry_offset;
+ user_buf_residue = len-count;
+ copy_size = min(user_buf_residue, formatted_line_residue);
+ if (copy_size) {
+ if (copy_to_user(user_buf + count, p_info->temp_buf
+ + entry_offset, copy_size))
+ return -EFAULT;
+ count += copy_size;
+ entry_offset += copy_size;
+ }
+ if (copy_size == formatted_line_residue) {
+ entry_offset = 0;
+ if (debug_next_entry(p_info))
+ goto out;
+ }
+ }
+out:
+ p_info->offset = *offset + count;
+ p_info->act_entry_offset = entry_offset;
+ *offset = p_info->offset;
+ return count;
+}
+
+/*
+ * debug_input:
+ * - called for user write()
+ * - calls input function of view
+ */
+static ssize_t debug_input(struct file *file, const char __user *user_buf,
+ size_t length, loff_t *offset)
+{
+ file_private_info_t *p_info;
+ int rc = 0;
+
+ mutex_lock(&debug_mutex);
+ p_info = ((file_private_info_t *) file->private_data);
+ if (p_info->view->input_proc) {
+ rc = p_info->view->input_proc(p_info->debug_info_org,
+ p_info->view, file, user_buf,
+ length, offset);
+ } else {
+ rc = -EPERM;
+ }
+ mutex_unlock(&debug_mutex);
+ return rc; /* number of input characters */
+}
+
+/*
+ * debug_open:
+ * - called for user open()
+ * - copies formated output to private_data area of the file
+ * handle
+ */
+static int debug_open(struct inode *inode, struct file *file)
+{
+ debug_info_t *debug_info, *debug_info_snapshot;
+ file_private_info_t *p_info;
+ int i, rc = 0;
+
+ mutex_lock(&debug_mutex);
+ debug_info = file_inode(file)->i_private;
+ /* find debug view */
+ for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+ if (!debug_info->views[i])
+ continue;
+ else if (debug_info->debugfs_entries[i] == file->f_path.dentry)
+ goto found; /* found view ! */
+ }
+ /* no entry found */
+ rc = -EINVAL;
+ goto out;
+
+found:
+
+ /* Make snapshot of current debug areas to get it consistent. */
+ /* To copy all the areas is only needed, if we have a view which */
+ /* formats the debug areas. */
+
+ if (!debug_info->views[i]->format_proc && !debug_info->views[i]->header_proc)
+ debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
+ else
+ debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
+
+ if (!debug_info_snapshot) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ p_info = kmalloc(sizeof(file_private_info_t), GFP_KERNEL);
+ if (!p_info) {
+ debug_info_free(debug_info_snapshot);
+ rc = -ENOMEM;
+ goto out;
+ }
+ p_info->offset = 0;
+ p_info->debug_info_snap = debug_info_snapshot;
+ p_info->debug_info_org = debug_info;
+ p_info->view = debug_info->views[i];
+ p_info->act_area = 0;
+ p_info->act_page = 0;
+ p_info->act_entry = DEBUG_PROLOG_ENTRY;
+ p_info->act_entry_offset = 0;
+ file->private_data = p_info;
+ debug_info_get(debug_info);
+ nonseekable_open(inode, file);
+out:
+ mutex_unlock(&debug_mutex);
+ return rc;
+}
+
+/*
+ * debug_close:
+ * - called for user close()
+ * - deletes private_data area of the file handle
+ */
+static int debug_close(struct inode *inode, struct file *file)
+{
+ file_private_info_t *p_info;
+
+ p_info = (file_private_info_t *) file->private_data;
+ if (p_info->debug_info_snap)
+ debug_info_free(p_info->debug_info_snap);
+ debug_info_put(p_info->debug_info_org);
+ kfree(file->private_data);
+ return 0; /* success */
+}
+
+/*
+ * debug_register_mode:
+ * - Creates and initializes debug area for the caller
+ * The mode parameter allows to specify access rights for the s390dbf files
+ * - Returns handle for debug area
+ */
+debug_info_t *debug_register_mode(const char *name, int pages_per_area,
+ int nr_areas, int buf_size, umode_t mode,
+ uid_t uid, gid_t gid)
+{
+ debug_info_t *rc = NULL;
+
+ /* Since debugfs currently does not support uid/gid other than root, */
+ /* we do not allow gid/uid != 0 until we get support for that. */
+ if ((uid != 0) || (gid != 0))
+ pr_warn("Root becomes the owner of all s390dbf files in sysfs\n");
+ BUG_ON(!initialized);
+ mutex_lock(&debug_mutex);
+
+ /* create new debug_info */
+ rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
+ if (!rc)
+ goto out;
+ debug_register_view(rc, &debug_level_view);
+ debug_register_view(rc, &debug_flush_view);
+ debug_register_view(rc, &debug_pages_view);
+out:
+ if (!rc)
+ pr_err("Registering debug feature %s failed\n", name);
+ mutex_unlock(&debug_mutex);
+ return rc;
+}
+EXPORT_SYMBOL(debug_register_mode);
+
+/*
+ * debug_register:
+ * - creates and initializes debug area for the caller
+ * - returns handle for debug area
+ */
+debug_info_t *debug_register(const char *name, int pages_per_area,
+ int nr_areas, int buf_size)
+{
+ return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
+ S_IRUSR | S_IWUSR, 0, 0);
+}
+EXPORT_SYMBOL(debug_register);
+
+/*
+ * debug_unregister:
+ * - give back debug area
+ */
+void debug_unregister(debug_info_t *id)
+{
+ if (!id)
+ return;
+ mutex_lock(&debug_mutex);
+ debug_info_put(id);
+ mutex_unlock(&debug_mutex);
+}
+EXPORT_SYMBOL(debug_unregister);
+
+/*
+ * debug_set_size:
+ * - set area size (number of pages) and number of areas
+ */
+static int debug_set_size(debug_info_t *id, int nr_areas, int pages_per_area)
+{
+ debug_entry_t ***new_areas;
+ unsigned long flags;
+ int rc = 0;
+
+ if (!id || (nr_areas <= 0) || (pages_per_area < 0))
+ return -EINVAL;
+ if (pages_per_area > 0) {
+ new_areas = debug_areas_alloc(pages_per_area, nr_areas);
+ if (!new_areas) {
+ pr_info("Allocating memory for %i pages failed\n",
+ pages_per_area);
+ rc = -ENOMEM;
+ goto out;
+ }
+ } else {
+ new_areas = NULL;
+ }
+ spin_lock_irqsave(&id->lock, flags);
+ debug_areas_free(id);
+ id->areas = new_areas;
+ id->nr_areas = nr_areas;
+ id->pages_per_area = pages_per_area;
+ id->active_area = 0;
+ memset(id->active_entries, 0, sizeof(int)*id->nr_areas);
+ memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
+ spin_unlock_irqrestore(&id->lock, flags);
+ pr_info("%s: set new size (%i pages)\n", id->name, pages_per_area);
+out:
+ return rc;
+}
+
+/*
+ * debug_set_level:
+ * - set actual debug level
+ */
+void debug_set_level(debug_info_t *id, int new_level)
+{
+ unsigned long flags;
+
+ if (!id)
+ return;
+ spin_lock_irqsave(&id->lock, flags);
+ if (new_level == DEBUG_OFF_LEVEL) {
+ id->level = DEBUG_OFF_LEVEL;
+ pr_info("%s: switched off\n", id->name);
+ } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
+ pr_info("%s: level %i is out of range (%i - %i)\n",
+ id->name, new_level, 0, DEBUG_MAX_LEVEL);
+ } else {
+ id->level = new_level;
+ }
+ spin_unlock_irqrestore(&id->lock, flags);
+}
+EXPORT_SYMBOL(debug_set_level);
+
+/*
+ * proceed_active_entry:
+ * - set active entry to next in the ring buffer
+ */
+static inline void proceed_active_entry(debug_info_t *id)
+{
+ if ((id->active_entries[id->active_area] += id->entry_size)
+ > (PAGE_SIZE - id->entry_size)) {
+ id->active_entries[id->active_area] = 0;
+ id->active_pages[id->active_area] =
+ (id->active_pages[id->active_area] + 1) %
+ id->pages_per_area;
+ }
+}
+
+/*
+ * proceed_active_area:
+ * - set active area to next in the ring buffer
+ */
+static inline void proceed_active_area(debug_info_t *id)
+{
+ id->active_area++;
+ id->active_area = id->active_area % id->nr_areas;
+}
+
+/*
+ * get_active_entry:
+ */
+static inline debug_entry_t *get_active_entry(debug_info_t *id)
+{
+ return (debug_entry_t *) (((char *) id->areas[id->active_area]
+ [id->active_pages[id->active_area]]) +
+ id->active_entries[id->active_area]);
+}
+
+/*
+ * debug_finish_entry:
+ * - set timestamp, caller address, cpu number etc.
+ */
+
+static inline void debug_finish_entry(debug_info_t *id, debug_entry_t *active,
+ int level, int exception)
+{
+ active->id.stck = get_tod_clock_fast() -
+ *(unsigned long long *) &tod_clock_base[1];
+ active->id.fields.cpuid = smp_processor_id();
+ active->caller = __builtin_return_address(0);
+ active->id.fields.exception = exception;
+ active->id.fields.level = level;
+ proceed_active_entry(id);
+ if (exception)
+ proceed_active_area(id);
+}
+
+static int debug_stoppable = 1;
+static int debug_active = 1;
+
+#define CTL_S390DBF_STOPPABLE 5678
+#define CTL_S390DBF_ACTIVE 5679
+
+/*
+ * proc handler for the running debug_active sysctl
+ * always allow read, allow write only if debug_stoppable is set or
+ * if debug_active is already off
+ */
+static int s390dbf_procactive(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ if (!write || debug_stoppable || !debug_active)
+ return proc_dointvec(table, write, buffer, lenp, ppos);
+ else
+ return 0;
+}
+
+static struct ctl_table s390dbf_table[] = {
+ {
+ .procname = "debug_stoppable",
+ .data = &debug_stoppable,
+ .maxlen = sizeof(int),
+ .mode = S_IRUGO | S_IWUSR,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "debug_active",
+ .data = &debug_active,
+ .maxlen = sizeof(int),
+ .mode = S_IRUGO | S_IWUSR,
+ .proc_handler = s390dbf_procactive,
+ },
+ { }
+};
+
+static struct ctl_table s390dbf_dir_table[] = {
+ {
+ .procname = "s390dbf",
+ .maxlen = 0,
+ .mode = S_IRUGO | S_IXUGO,
+ .child = s390dbf_table,
+ },
+ { }
+};
+
+static struct ctl_table_header *s390dbf_sysctl_header;
+
+void debug_stop_all(void)
+{
+ if (debug_stoppable)
+ debug_active = 0;
+}
+EXPORT_SYMBOL(debug_stop_all);
+
+void debug_set_critical(void)
+{
+ debug_critical = 1;
+}
+
+/*
+ * debug_event_common:
+ * - write debug entry with given size
+ */
+debug_entry_t *debug_event_common(debug_info_t *id, int level, const void *buf,
+ int len)
+{
+ debug_entry_t *active;
+ unsigned long flags;
+
+ if (!debug_active || !id->areas)
+ return NULL;
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else {
+ spin_lock_irqsave(&id->lock, flags);
+ }
+ do {
+ active = get_active_entry(id);
+ memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
+ if (len < id->buf_size)
+ memset((DEBUG_DATA(active)) + len, 0, id->buf_size - len);
+ debug_finish_entry(id, active, level, 0);
+ len -= id->buf_size;
+ buf += id->buf_size;
+ } while (len > 0);
+
+ spin_unlock_irqrestore(&id->lock, flags);
+ return active;
+}
+EXPORT_SYMBOL(debug_event_common);
+
+/*
+ * debug_exception_common:
+ * - write debug entry with given size and switch to next debug area
+ */
+debug_entry_t *debug_exception_common(debug_info_t *id, int level,
+ const void *buf, int len)
+{
+ debug_entry_t *active;
+ unsigned long flags;
+
+ if (!debug_active || !id->areas)
+ return NULL;
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else {
+ spin_lock_irqsave(&id->lock, flags);
+ }
+ do {
+ active = get_active_entry(id);
+ memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
+ if (len < id->buf_size)
+ memset((DEBUG_DATA(active)) + len, 0, id->buf_size - len);
+ debug_finish_entry(id, active, level, len <= id->buf_size);
+ len -= id->buf_size;
+ buf += id->buf_size;
+ } while (len > 0);
+
+ spin_unlock_irqrestore(&id->lock, flags);
+ return active;
+}
+EXPORT_SYMBOL(debug_exception_common);
+
+/*
+ * counts arguments in format string for sprintf view
+ */
+static inline int debug_count_numargs(char *string)
+{
+ int numargs = 0;
+
+ while (*string) {
+ if (*string++ == '%')
+ numargs++;
+ }
+ return numargs;
+}
+
+/*
+ * debug_sprintf_event:
+ */
+debug_entry_t *__debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
+{
+ debug_sprintf_entry_t *curr_event;
+ debug_entry_t *active;
+ unsigned long flags;
+ int numargs, idx;
+ va_list ap;
+
+ if (!debug_active || !id->areas)
+ return NULL;
+ numargs = debug_count_numargs(string);
+
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else {
+ spin_lock_irqsave(&id->lock, flags);
+ }
+ active = get_active_entry(id);
+ curr_event = (debug_sprintf_entry_t *) DEBUG_DATA(active);
+ va_start(ap, string);
+ curr_event->string = string;
+ for (idx = 0; idx < min(numargs, (int)(id->buf_size / sizeof(long)) - 1); idx++)
+ curr_event->args[idx] = va_arg(ap, long);
+ va_end(ap);
+ debug_finish_entry(id, active, level, 0);
+ spin_unlock_irqrestore(&id->lock, flags);
+
+ return active;
+}
+EXPORT_SYMBOL(__debug_sprintf_event);
+
+/*
+ * debug_sprintf_exception:
+ */
+debug_entry_t *__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
+{
+ debug_sprintf_entry_t *curr_event;
+ debug_entry_t *active;
+ unsigned long flags;
+ int numargs, idx;
+ va_list ap;
+
+ if (!debug_active || !id->areas)
+ return NULL;
+
+ numargs = debug_count_numargs(string);
+
+ if (debug_critical) {
+ if (!spin_trylock_irqsave(&id->lock, flags))
+ return NULL;
+ } else {
+ spin_lock_irqsave(&id->lock, flags);
+ }
+ active = get_active_entry(id);
+ curr_event = (debug_sprintf_entry_t *)DEBUG_DATA(active);
+ va_start(ap, string);
+ curr_event->string = string;
+ for (idx = 0; idx < min(numargs, (int)(id->buf_size / sizeof(long)) - 1); idx++)
+ curr_event->args[idx] = va_arg(ap, long);
+ va_end(ap);
+ debug_finish_entry(id, active, level, 1);
+ spin_unlock_irqrestore(&id->lock, flags);
+
+ return active;
+}
+EXPORT_SYMBOL(__debug_sprintf_exception);
+
+/*
+ * debug_register_view:
+ */
+int debug_register_view(debug_info_t *id, struct debug_view *view)
+{
+ unsigned long flags;
+ struct dentry *pde;
+ umode_t mode;
+ int rc = 0;
+ int i;
+
+ if (!id)
+ goto out;
+ mode = (id->mode | S_IFREG) & ~S_IXUGO;
+ if (!(view->prolog_proc || view->format_proc || view->header_proc))
+ mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
+ if (!view->input_proc)
+ mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
+ pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
+ id, &debug_file_ops);
+ if (!pde) {
+ pr_err("Registering view %s/%s failed due to out of "
+ "memory\n", id->name, view->name);
+ rc = -1;
+ goto out;
+ }
+ spin_lock_irqsave(&id->lock, flags);
+ for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+ if (!id->views[i])
+ break;
+ }
+ if (i == DEBUG_MAX_VIEWS) {
+ pr_err("Registering view %s/%s would exceed the maximum "
+ "number of views %i\n", id->name, view->name, i);
+ rc = -1;
+ } else {
+ id->views[i] = view;
+ id->debugfs_entries[i] = pde;
+ }
+ spin_unlock_irqrestore(&id->lock, flags);
+ if (rc)
+ debugfs_remove(pde);
+out:
+ return rc;
+}
+EXPORT_SYMBOL(debug_register_view);
+
+/*
+ * debug_unregister_view:
+ */
+int debug_unregister_view(debug_info_t *id, struct debug_view *view)
+{
+ struct dentry *dentry = NULL;
+ unsigned long flags;
+ int i, rc = 0;
+
+ if (!id)
+ goto out;
+ spin_lock_irqsave(&id->lock, flags);
+ for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
+ if (id->views[i] == view)
+ break;
+ }
+ if (i == DEBUG_MAX_VIEWS) {
+ rc = -1;
+ } else {
+ dentry = id->debugfs_entries[i];
+ id->views[i] = NULL;
+ id->debugfs_entries[i] = NULL;
+ }
+ spin_unlock_irqrestore(&id->lock, flags);
+ debugfs_remove(dentry);
+out:
+ return rc;
+}
+EXPORT_SYMBOL(debug_unregister_view);
+
+static inline char *debug_get_user_string(const char __user *user_buf,
+ size_t user_len)
+{
+ char *buffer;
+
+ buffer = kmalloc(user_len + 1, GFP_KERNEL);
+ if (!buffer)
+ return ERR_PTR(-ENOMEM);
+ if (copy_from_user(buffer, user_buf, user_len) != 0) {
+ kfree(buffer);
+ return ERR_PTR(-EFAULT);
+ }
+ /* got the string, now strip linefeed. */
+ if (buffer[user_len - 1] == '\n')
+ buffer[user_len - 1] = 0;
+ else
+ buffer[user_len] = 0;
+ return buffer;
+}
+
+static inline int debug_get_uint(char *buf)
+{
+ int rc;
+
+ buf = skip_spaces(buf);
+ rc = simple_strtoul(buf, &buf, 10);
+ if (*buf)
+ rc = -EINVAL;
+ return rc;
+}
+
+/*
+ * functions for debug-views
+ ***********************************
+*/
+
+/*
+ * prints out actual debug level
+ */
+
+static int debug_prolog_pages_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf)
+{
+ return sprintf(out_buf, "%i\n", id->pages_per_area);
+}
+
+/*
+ * reads new size (number of pages per debug area)
+ */
+
+static int debug_input_pages_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_len, loff_t *offset)
+{
+ int rc, new_pages;
+ char *str;
+
+ if (user_len > 0x10000)
+ user_len = 0x10000;
+ if (*offset != 0) {
+ rc = -EPIPE;
+ goto out;
+ }
+ str = debug_get_user_string(user_buf, user_len);
+ if (IS_ERR(str)) {
+ rc = PTR_ERR(str);
+ goto out;
+ }
+ new_pages = debug_get_uint(str);
+ if (new_pages < 0) {
+ rc = -EINVAL;
+ goto free_str;
+ }
+ rc = debug_set_size(id, id->nr_areas, new_pages);
+ if (rc != 0) {
+ rc = -EINVAL;
+ goto free_str;
+ }
+ rc = user_len;
+free_str:
+ kfree(str);
+out:
+ *offset += user_len;
+ return rc; /* number of input characters */
+}
+
+/*
+ * prints out actual debug level
+ */
+static int debug_prolog_level_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf)
+{
+ int rc = 0;
+
+ if (id->level == DEBUG_OFF_LEVEL)
+ rc = sprintf(out_buf, "-\n");
+ else
+ rc = sprintf(out_buf, "%i\n", id->level);
+ return rc;
+}
+
+/*
+ * reads new debug level
+ */
+static int debug_input_level_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_len, loff_t *offset)
+{
+ int rc, new_level;
+ char *str;
+
+ if (user_len > 0x10000)
+ user_len = 0x10000;
+ if (*offset != 0) {
+ rc = -EPIPE;
+ goto out;
+ }
+ str = debug_get_user_string(user_buf, user_len);
+ if (IS_ERR(str)) {
+ rc = PTR_ERR(str);
+ goto out;
+ }
+ if (str[0] == '-') {
+ debug_set_level(id, DEBUG_OFF_LEVEL);
+ rc = user_len;
+ goto free_str;
+ } else {
+ new_level = debug_get_uint(str);
+ }
+ if (new_level < 0) {
+ pr_warn("%s is not a valid level for a debug feature\n", str);
+ rc = -EINVAL;
+ } else {
+ debug_set_level(id, new_level);
+ rc = user_len;
+ }
+free_str:
+ kfree(str);
+out:
+ *offset += user_len;
+ return rc; /* number of input characters */
+}
+
+/*
+ * flushes debug areas
+ */
+static void debug_flush(debug_info_t *id, int area)
+{
+ unsigned long flags;
+ int i, j;
+
+ if (!id || !id->areas)
+ return;
+ spin_lock_irqsave(&id->lock, flags);
+ if (area == DEBUG_FLUSH_ALL) {
+ id->active_area = 0;
+ memset(id->active_entries, 0, id->nr_areas * sizeof(int));
+ for (i = 0; i < id->nr_areas; i++) {
+ id->active_pages[i] = 0;
+ for (j = 0; j < id->pages_per_area; j++)
+ memset(id->areas[i][j], 0, PAGE_SIZE);
+ }
+ } else if (area >= 0 && area < id->nr_areas) {
+ id->active_entries[area] = 0;
+ id->active_pages[area] = 0;
+ for (i = 0; i < id->pages_per_area; i++)
+ memset(id->areas[area][i], 0, PAGE_SIZE);
+ }
+ spin_unlock_irqrestore(&id->lock, flags);
+}
+
+/*
+ * view function: flushes debug areas
+ */
+static int debug_input_flush_fn(debug_info_t *id, struct debug_view *view,
+ struct file *file, const char __user *user_buf,
+ size_t user_len, loff_t *offset)
+{
+ char input_buf[1];
+ int rc = user_len;
+
+ if (user_len > 0x10000)
+ user_len = 0x10000;
+ if (*offset != 0) {
+ rc = -EPIPE;
+ goto out;
+ }
+ if (copy_from_user(input_buf, user_buf, 1)) {
+ rc = -EFAULT;
+ goto out;
+ }
+ if (input_buf[0] == '-') {
+ debug_flush(id, DEBUG_FLUSH_ALL);
+ goto out;
+ }
+ if (isdigit(input_buf[0])) {
+ int area = ((int) input_buf[0] - (int) '0');
+
+ debug_flush(id, area);
+ goto out;
+ }
+
+ pr_info("Flushing debug data failed because %c is not a valid "
+ "area\n", input_buf[0]);
+
+out:
+ *offset += user_len;
+ return rc; /* number of input characters */
+}
+
+/*
+ * prints debug header in raw format
+ */
+static int debug_raw_header_fn(debug_info_t *id, struct debug_view *view,
+ int area, debug_entry_t *entry, char *out_buf)
+{
+ int rc;
+
+ rc = sizeof(debug_entry_t);
+ memcpy(out_buf, entry, sizeof(debug_entry_t));
+ return rc;
+}
+
+/*
+ * prints debug data in raw format
+ */
+static int debug_raw_format_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf, const char *in_buf)
+{
+ int rc;
+
+ rc = id->buf_size;
+ memcpy(out_buf, in_buf, id->buf_size);
+ return rc;
+}
+
+/*
+ * prints debug data in hex/ascii format
+ */
+static int debug_hex_ascii_format_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf, const char *in_buf)
+{
+ int i, rc = 0;
+
+ for (i = 0; i < id->buf_size; i++)
+ rc += sprintf(out_buf + rc, "%02x ", ((unsigned char *) in_buf)[i]);
+ rc += sprintf(out_buf + rc, "| ");
+ for (i = 0; i < id->buf_size; i++) {
+ unsigned char c = in_buf[i];
+
+ if (isascii(c) && isprint(c))
+ rc += sprintf(out_buf + rc, "%c", c);
+ else
+ rc += sprintf(out_buf + rc, ".");
+ }
+ rc += sprintf(out_buf + rc, "\n");
+ return rc;
+}
+
+/*
+ * prints header for debug entry
+ */
+int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,
+ int area, debug_entry_t *entry, char *out_buf)
+{
+ unsigned long base, sec, usec;
+ unsigned long caller;
+ unsigned int level;
+ char *except_str;
+ int rc = 0;
+
+ level = entry->id.fields.level;
+ base = (*(unsigned long *) &tod_clock_base[0]) >> 4;
+ sec = (entry->id.stck >> 12) + base - (TOD_UNIX_EPOCH >> 12);
+ usec = do_div(sec, USEC_PER_SEC);
+
+ if (entry->id.fields.exception)
+ except_str = "*";
+ else
+ except_str = "-";
+ caller = (unsigned long) entry->caller;
+ rc += sprintf(out_buf, "%02i %011ld:%06lu %1u %1s %02i %pK ",
+ area, sec, usec, level, except_str,
+ entry->id.fields.cpuid, (void *)caller);
+ return rc;
+}
+EXPORT_SYMBOL(debug_dflt_header_fn);
+
+/*
+ * prints debug data sprintf-formated:
+ * debug_sprinf_event/exception calls must be used together with this view
+ */
+
+#define DEBUG_SPRINTF_MAX_ARGS 10
+
+static int debug_sprintf_format_fn(debug_info_t *id, struct debug_view *view,
+ char *out_buf, debug_sprintf_entry_t *curr_event)
+{
+ int num_longs, num_used_args = 0, i, rc = 0;
+ int index[DEBUG_SPRINTF_MAX_ARGS];
+
+ /* count of longs fit into one entry */
+ num_longs = id->buf_size / sizeof(long);
+
+ if (num_longs < 1)
+ goto out; /* bufsize of entry too small */
+ if (num_longs == 1) {
+ /* no args, we use only the string */
+ strcpy(out_buf, curr_event->string);
+ rc = strlen(curr_event->string);
+ goto out;
+ }
+
+ /* number of arguments used for sprintf (without the format string) */
+ num_used_args = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
+
+ memset(index, 0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
+
+ for (i = 0; i < num_used_args; i++)
+ index[i] = i;
+
+ rc = sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
+ curr_event->args[index[1]], curr_event->args[index[2]],
+ curr_event->args[index[3]], curr_event->args[index[4]],
+ curr_event->args[index[5]], curr_event->args[index[6]],
+ curr_event->args[index[7]], curr_event->args[index[8]],
+ curr_event->args[index[9]]);
+out:
+ return rc;
+}
+
+/*
+ * debug_init:
+ * - is called exactly once to initialize the debug feature
+ */
+static int __init debug_init(void)
+{
+ s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
+ mutex_lock(&debug_mutex);
+ debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT, NULL);
+ initialized = 1;
+ mutex_unlock(&debug_mutex);
+ return 0;
+}
+postcore_initcall(debug_init);