diff options
Diffstat (limited to 'arch/s390/kernel/debug.c')
| -rw-r--r-- | arch/s390/kernel/debug.c | 1567 |
1 files changed, 877 insertions, 690 deletions
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c index f1279dc2e1bc..71cdb6845dd7 100644 --- a/arch/s390/kernel/debug.c +++ b/arch/s390/kernel/debug.c @@ -1,16 +1,16 @@ +// SPDX-License-Identifier: GPL-2.0 /* * S/390 debug facility * - * Copyright IBM Corp. 1999, 2012 + * Copyright IBM Corp. 1999, 2020 * * Author(s): Michael Holzheu (holzheu@de.ibm.com), - * Holger Smolinski (Holger.Smolinski@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 +#define pr_fmt(fmt) "s390dbf: " fmt #include <linux/stddef.h> #include <linux/kernel.h> @@ -19,10 +19,12 @@ #include <linux/ctype.h> #include <linux/string.h> #include <linux/sysctl.h> -#include <asm/uaccess.h> -#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/export.h> #include <linux/init.h> #include <linux/fs.h> +#include <linux/math.h> +#include <linux/minmax.h> #include <linux/debugfs.h> #include <asm/debug.h> @@ -36,82 +38,67 @@ 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 */ + int act_area; /* number of last formatted area */ + int act_page; /* act page in given area */ + int act_entry; /* last formatted entry (offset */ + /* relative to beginning of last */ + /* formatted page) */ + size_t act_entry_offset; /* up to this offset we copied */ + /* in last read the last formatted */ /* entry to userland */ char temp_buf[2048]; /* buffer for output */ - debug_info_t *debug_info_org; /* original debug information */ + 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 -{ +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) + /* + * 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]; + long args[]; } debug_sprintf_entry_t; - -/* internal function prototyes */ +/* internal function prototypes */ static int debug_init(void); static ssize_t debug_output(struct file *file, char __user *user_buf, - size_t user_len, loff_t * offset); + 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); + 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); + 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); +static int debug_prolog_level_fn(debug_info_t *id, + struct debug_view *view, char *out_buf, + size_t out_buf_size); +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, + size_t out_buf_size); +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, size_t out_buf_size, + const char *in_buf); +static void debug_areas_swap(debug_info_t *a, debug_info_t *b); +static void debug_events_append(debug_info_t *dest, debug_info_t *src); /* 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, @@ -141,19 +128,19 @@ static struct debug_view debug_pages_view = { }; static struct debug_view debug_flush_view = { - "flush", - NULL, - NULL, - NULL, - &debug_input_flush_fn, - NULL + "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, + &debug_sprintf_format_fn, NULL, NULL }; @@ -164,20 +151,19 @@ static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION; /* static globals */ -static debug_info_t *debug_area_first = NULL; -static debug_info_t *debug_area_last = NULL; +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, + .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; @@ -190,29 +176,26 @@ static struct dentry *debug_debugfs_root_entry; * areas[areanumber][pagenumber][pageoffset] */ -static debug_entry_t*** -debug_areas_alloc(int pages_per_area, int nr_areas) +static debug_entry_t ***debug_areas_alloc(int pages_per_area, int nr_areas) { - debug_entry_t*** areas; - int i,j; + debug_entry_t ***areas; + int i, j; - areas = kmalloc(nr_areas * - sizeof(debug_entry_t**), - GFP_KERNEL); + 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(pages_per_area * - sizeof(debug_entry_t*),GFP_KERNEL); - if (!areas[i]) { + /* GFP_NOWARN to avoid user triggerable WARN, we handle fails */ + areas[i] = kmalloc_array(pages_per_area, + sizeof(debug_entry_t *), + GFP_KERNEL | __GFP_NOWARN); + if (!areas[i]) goto fail_malloc_areas2; - } - for(j = 0; j < pages_per_area; j++) { + 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--) { + if (!areas[i][j]) { + for (j--; j >= 0 ; j--) kfree(areas[i][j]); - } kfree(areas[i]); goto fail_malloc_areas2; } @@ -221,63 +204,56 @@ debug_areas_alloc(int pages_per_area, int nr_areas) return areas; fail_malloc_areas2: - for(i--; i >= 0; i--){ - for(j=0; j < pages_per_area;j++){ + 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) +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; + debug_info_t *rc; /* alloc everything */ - rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL); - if(!rc) + if (!rc) goto fail_malloc_rc; rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); - if(!rc->active_entries) + if (!rc->active_entries) goto fail_malloc_active_entries; rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); - if(!rc->active_pages) + if (!rc->active_pages) goto fail_malloc_active_pages; - if((mode == ALL_AREAS) && (pages_per_area != 0)){ + if ((mode == ALL_AREAS) && (pages_per_area != 0)) { rc->areas = debug_areas_alloc(pages_per_area, nr_areas); - if(!rc->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->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)); + rc->level = level; + rc->buf_size = buf_size; + rc->entry_size = sizeof(debug_entry_t) + buf_size; + strscpy(rc->name, name); memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *)); - memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS * - sizeof(struct dentry*)); - atomic_set(&(rc->ref_count), 0); + memset(rc->debugfs_entries, 0, DEBUG_MAX_VIEWS * sizeof(struct dentry *)); + refcount_set(&(rc->ref_count), 0); return rc; @@ -295,18 +271,15 @@ fail_malloc_rc: * debug_areas_free * - free all debug areas */ - -static void -debug_areas_free(debug_info_t* db_info) +static void debug_areas_free(debug_info_t *db_info) { - int i,j; + int i, j; - if(!db_info->areas) + if (!db_info->areas) return; for (i = 0; i < db_info->nr_areas; i++) { - for(j = 0; j < db_info->pages_per_area; j++) { + 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); @@ -317,9 +290,8 @@ debug_areas_free(debug_info_t* db_info) * debug_info_free * - free memory debug-info */ - -static void -debug_info_free(debug_info_t* db_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); @@ -331,37 +303,18 @@ debug_info_free(debug_info_t* db_info){ * - 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) +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; + debug_info_t *rc; - rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size, - DEBUG_DEFAULT_LEVEL, ALL_AREAS); - if(!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; - - debug_info_get(rc); + refcount_set(&rc->ref_count, 1); out: return rc; } @@ -370,24 +323,22 @@ out: * debug_info_copy * - copy debug-info */ - -static debug_info_t* -debug_info_copy(debug_info_t* in, int mode) +static debug_info_t *debug_info_copy(debug_info_t *in, int mode) { - int i,j; - debug_info_t* rc; - unsigned long flags; + 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) + 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)) { + if ((rc->pages_per_area == in->pages_per_area) && + (rc->nr_areas == in->nr_areas)) { break; } spin_unlock_irqrestore(&in->lock, flags); @@ -395,155 +346,222 @@ debug_info_copy(debug_info_t* in, int mode) } while (1); if (mode == NO_AREAS) - goto out; + 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); - } - } + 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); + rc->active_pages[i] = in->active_pages[i]; + rc->active_entries[i] = in->active_entries[i]; + } + rc->active_area = in->active_area; out: - spin_unlock_irqrestore(&in->lock, flags); - return rc; + 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) +static void debug_info_get(debug_info_t *db_info) { if (db_info) - atomic_inc(&db_info->ref_count); + 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) +static void debug_info_put(debug_info_t *db_info) { - int i; - if (!db_info) return; - if (atomic_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; + if (refcount_dec_and_test(&db_info->ref_count)) debug_info_free(db_info); - } } /* * debug_format_entry: - * - format one debug entry and return size of formated data + * - format one debug entry and return size of formatted data */ - -static int -debug_format_entry(file_private_info_t *p_info) +static int debug_format_entry(file_private_info_t *p_info) { - debug_info_t *id_snap = p_info->debug_info_snap; + 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){ + + 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); + if (view->prolog_proc) { + len += view->prolog_proc(id_snap, view, p_info->temp_buf, + sizeof(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) + act_entry = (debug_entry_t *) ((char *)id_snap->areas[p_info->act_area] + [p_info->act_page] + p_info->act_entry); + + if (act_entry->clock == 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) + act_entry, p_info->temp_buf + len, + sizeof(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)); + sizeof(p_info->temp_buf) - len, + DEBUG_DATA(act_entry)); + } out: - return len; + return len; } -/* - * debug_next_entry: - * - goto next entry in p_info +/** + * debug_next_entry - Go to the next entry + * @p_info: Private info that is manipulated + * + * Sets the current position in @p_info to the next entry. If no further entry + * exists the current position is set to one after the end the return value + * indicates that no further entries exist. + * + * Return: True if there are more following entries, false otherwise */ - -static inline int -debug_next_entry(file_private_info_t *p_info) +static inline bool 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){ + if (p_info->act_entry == DEBUG_PROLOG_ENTRY) { p_info->act_entry = 0; p_info->act_page = 0; - goto out; + return true; } - if(!id->areas) - return 1; + if (!id->areas) + return false; 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)){ + 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) { + if ((p_info->act_page % id->pages_per_area) == 0) { /* next area */ - p_info->act_area++; - p_info->act_page=0; + p_info->act_area++; + p_info->act_page = 0; } - if(p_info->act_area >= id->nr_areas) - return 1; + if (p_info->act_area >= id->nr_areas) + return false; } -out: - return 0; + return true; +} + +/** + * debug_to_act_entry - Go to the currently active entry + * @p_info: Private info that is manipulated + * + * Sets the current position in @p_info to the currently active + * entry of @p_info->debug_info_snap + */ +static void debug_to_act_entry(file_private_info_t *p_info) +{ + debug_info_t *snap_id; + + snap_id = p_info->debug_info_snap; + p_info->act_area = snap_id->active_area; + p_info->act_page = snap_id->active_pages[snap_id->active_area]; + p_info->act_entry = snap_id->active_entries[snap_id->active_area]; +} + +/** + * debug_prev_entry - Go to the previous entry + * @p_info: Private info that is manipulated + * + * Sets the current position in @p_info to the previous entry. If no previous entry + * exists the current position is set left as DEBUG_PROLOG_ENTRY and the return value + * indicates that no previous entries exist. + * + * Return: True if there are more previous entries, false otherwise + */ + +static inline bool debug_prev_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) + debug_to_act_entry(p_info); + if (!id->areas) + return false; + p_info->act_entry -= id->entry_size; + /* switch to prev page, if we reached the beginning of the page */ + if (p_info->act_entry < 0) { + /* end of previous page */ + p_info->act_entry = rounddown(PAGE_SIZE, id->entry_size) - id->entry_size; + p_info->act_page--; + if (p_info->act_page < 0) { + /* previous area */ + p_info->act_area--; + p_info->act_page = id->pages_per_area - 1; + } + if (p_info->act_area < 0) + p_info->act_area = (id->nr_areas - 1) % id->nr_areas; + } + /* check full circle */ + if (id->active_area == p_info->act_area && + id->active_pages[id->active_area] == p_info->act_page && + id->active_entries[id->active_area] == p_info->act_entry) + return false; + return true; +} + +/** + * debug_move_entry - Go to next entry in either the forward or backward direction + * @p_info: Private info that is manipulated + * @reverse: If true go to the next entry in reverse i.e. previous + * + * Sets the current position in @p_info to the next (@reverse == false) or + * previous (@reverse == true) entry. + * + * Return: True if there are further entries in that direction, + * false otherwise. + */ +static bool debug_move_entry(file_private_info_t *p_info, bool reverse) +{ + if (reverse) + return debug_prev_entry(p_info); + else + return debug_next_entry(p_info); } /* * debug_output: * - called for user read() - * - copies formated debug entries to the user buffer + * - copies formatted 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 */ +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) + 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) + 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_size; + while (count < len) { int formatted_line_residue; + int formatted_line_size; int user_buf_residue; size_t copy_size; @@ -551,21 +569,21 @@ debug_output(struct file *file, /* file descriptor */ 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_size) { if (copy_to_user(user_buf + count, p_info->temp_buf - + entry_offset, copy_size)) + + entry_offset, copy_size)) return -EFAULT; count += copy_size; entry_offset += copy_size; } - if(copy_size == formatted_line_residue){ + if (copy_size == formatted_line_residue) { entry_offset = 0; - if(debug_next_entry(p_info)) + if (!debug_next_entry(p_info)) goto out; } } out: - p_info->offset = *offset + count; + p_info->offset = *offset + count; p_info->act_entry_offset = entry_offset; *offset = p_info->offset; return count; @@ -576,39 +594,72 @@ out: * - 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) +static ssize_t debug_input(struct file *file, const char __user *user_buf, + size_t length, loff_t *offset) { - int rc = 0; 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) + 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 + } else { rc = -EPERM; + } mutex_unlock(&debug_mutex); - return rc; /* number of input characters */ + return rc; /* number of input characters */ +} + +static file_private_info_t *debug_file_private_alloc(debug_info_t *debug_info, + struct debug_view *view) +{ + debug_info_t *debug_info_snapshot; + file_private_info_t *p_info; + + /* + * 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 (!view->format_proc && !view->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) + return NULL; + p_info = kmalloc(sizeof(file_private_info_t), GFP_KERNEL); + if (!p_info) { + debug_info_free(debug_info_snapshot); + return NULL; + } + p_info->offset = 0; + p_info->debug_info_snap = debug_info_snapshot; + p_info->debug_info_org = debug_info; + p_info->view = view; + p_info->act_area = 0; + p_info->act_page = 0; + p_info->act_entry = DEBUG_PROLOG_ENTRY; + p_info->act_entry_offset = 0; + debug_info_get(debug_info); + + return p_info; } /* * debug_open: * - called for user open() - * - copies formated output to private_data area of the file + * - copies formatted output to private_data area of the file * handle */ - -static int -debug_open(struct inode *inode, struct file *file) +static int debug_open(struct inode *inode, struct file *file) { - int i, rc = 0; + debug_info_t *debug_info; file_private_info_t *p_info; - debug_info_t *debug_info, *debug_info_snapshot; + int i, rc = 0; mutex_lock(&debug_mutex); debug_info = file_inode(file)->i_private; @@ -616,80 +667,140 @@ debug_open(struct inode *inode, struct file *file) 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 ! */ - } + 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); + p_info = debug_file_private_alloc(debug_info, debug_info->views[i]); + if (!p_info) { 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; } +static void debug_file_private_free(file_private_info_t *p_info) +{ + if (p_info->debug_info_snap) + debug_info_free(p_info->debug_info_snap); + debug_info_put(p_info->debug_info_org); + kfree(p_info); +} + /* * debug_close: * - called for user close() * - deletes private_data area of the file handle */ - -static int -debug_close(struct inode *inode, struct file *file) +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_file_private_free(p_info); + file->private_data = NULL; + 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_dump - Get a textual representation of debug info, or as much as fits + * @id: Debug information to use + * @view: View with which to dump the debug information + * @buf: Buffer the textual debug data representation is written to + * @buf_size: Size of the buffer, including the trailing '\0' byte + * @reverse: Go backwards from the last written entry + * + * This function may be used whenever a textual representation of the debug + * information is required without using an s390dbf file. + * + * Note: It is the callers responsibility to supply a view that is compatible + * with the debug information data. + * + * Return: On success returns the number of bytes written to the buffer not + * including the trailing '\0' byte. If bug_size == 0 the function returns 0. + * On failure an error code less than 0 is returned. */ +ssize_t debug_dump(debug_info_t *id, struct debug_view *view, + char *buf, size_t buf_size, bool reverse) +{ + file_private_info_t *p_info; + size_t size, offset = 0; + + /* Need space for '\0' byte */ + if (buf_size < 1) + return 0; + buf_size--; + + p_info = debug_file_private_alloc(id, view); + if (!p_info) + return -ENOMEM; + + /* There is always at least the DEBUG_PROLOG_ENTRY */ + do { + size = debug_format_entry(p_info); + size = min(size, buf_size - offset); + memcpy(buf + offset, p_info->temp_buf, size); + offset += size; + if (offset >= buf_size) + break; + } while (debug_move_entry(p_info, reverse)); + debug_file_private_free(p_info); + buf[offset] = '\0'; + + return offset; +} +/* Create debugfs entries and add to internal list. */ +static void _debug_register(debug_info_t *id) +{ + /* create root directory */ + id->debugfs_root_entry = debugfs_create_dir(id->name, + debug_debugfs_root_entry); + + /* append new element to linked list */ + if (!debug_area_first) { + /* first element in list */ + debug_area_first = id; + id->prev = NULL; + } else { + /* append element to end of list */ + debug_area_last->next = id; + id->prev = debug_area_last; + } + debug_area_last = id; + id->next = NULL; + + debug_register_view(id, &debug_level_view); + debug_register_view(id, &debug_flush_view); + debug_register_view(id, &debug_pages_view); +} + +/** + * debug_register_mode() - creates and initializes debug area. + * + * @name: Name of debug log (e.g. used for debugfs entry) + * @pages_per_area: Number of pages, which will be allocated per area + * @nr_areas: Number of debug areas + * @buf_size: Size of data area in each debug entry + * @mode: File mode for debugfs files. E.g. S_IRWXUGO + * @uid: User ID for debugfs files. Currently only 0 is supported. + * @gid: Group ID for debugfs files. Currently only 0 is supported. + * + * Return: + * - Handle for generated debug area + * - %NULL if register failed + * + * Allocates memory for a debug log. + * Must not be called within an interrupt handler. + */ 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) @@ -699,34 +810,38 @@ debug_info_t *debug_register_mode(const char *name, int pages_per_area, /* 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_warning("Root becomes the owner of all s390dbf files " - "in sysfs\n"); + pr_warn("Root becomes the owner of all s390dbf files in sysfs\n"); BUG_ON(!initialized); - mutex_lock(&debug_mutex); - - /* create new debug_info */ + /* 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){ + if (rc) { + mutex_lock(&debug_mutex); + _debug_register(rc); + mutex_unlock(&debug_mutex); + } else { 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_register() - creates and initializes debug area with default file mode. + * + * @name: Name of debug log (e.g. used for debugfs entry) + * @pages_per_area: Number of pages, which will be allocated per area + * @nr_areas: Number of debug areas + * @buf_size: Size of data area in each debug entry + * + * Return: + * - Handle for generated debug area + * - %NULL if register failed + * + * Allocates memory for a debug log. + * The debugfs file mode access permissions are read and write for user. + * Must not be called within an interrupt handler. */ - debug_info_t *debug_register(const char *name, int pages_per_area, int nr_areas, int buf_size) { @@ -735,22 +850,99 @@ debug_info_t *debug_register(const char *name, int pages_per_area, } EXPORT_SYMBOL(debug_register); -/* - * debug_unregister: - * - give back debug area +/** + * debug_register_static() - registers a static debug area + * + * @id: Handle for static debug area + * @pages_per_area: Number of pages per area + * @nr_areas: Number of debug areas + * + * Register debug_info_t defined using DEFINE_STATIC_DEBUG_INFO. + * + * Note: This function is called automatically via an initcall generated by + * DEFINE_STATIC_DEBUG_INFO. */ +void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas) +{ + unsigned long flags; + debug_info_t *copy; + + if (!initialized) { + pr_err("Tried to register debug feature %s too early\n", + id->name); + return; + } + + copy = debug_info_alloc("", pages_per_area, nr_areas, id->buf_size, + id->level, ALL_AREAS); + if (!copy) { + pr_err("Registering debug feature %s failed\n", id->name); + + /* Clear pointers to prevent tracing into released initdata. */ + spin_lock_irqsave(&id->lock, flags); + id->areas = NULL; + id->active_pages = NULL; + id->active_entries = NULL; + spin_unlock_irqrestore(&id->lock, flags); + + return; + } + + /* Replace static trace area with dynamic copy. */ + spin_lock_irqsave(&id->lock, flags); + debug_events_append(copy, id); + debug_areas_swap(id, copy); + spin_unlock_irqrestore(&id->lock, flags); + + /* Clear pointers to initdata and discard copy. */ + copy->areas = NULL; + copy->active_pages = NULL; + copy->active_entries = NULL; + debug_info_free(copy); + + mutex_lock(&debug_mutex); + _debug_register(id); + mutex_unlock(&debug_mutex); +} -void -debug_unregister(debug_info_t * id) +/* Remove debugfs entries and remove from internal list. */ +static void _debug_unregister(debug_info_t *id) +{ + int i; + + for (i = 0; i < DEBUG_MAX_VIEWS; i++) { + if (!id->views[i]) + continue; + debugfs_remove(id->debugfs_entries[i]); + } + debugfs_remove(id->debugfs_root_entry); + if (id == debug_area_first) + debug_area_first = id->next; + if (id == debug_area_last) + debug_area_last = id->prev; + if (id->prev) + id->prev->next = id->next; + if (id->next) + id->next->prev = id->prev; +} + +/** + * debug_unregister() - give back debug area. + * + * @id: handle for debug log + * + * Return: + * none + */ +void debug_unregister(debug_info_t *id) { if (!id) - goto out; + return; mutex_lock(&debug_mutex); - debug_info_put(id); + _debug_unregister(id); mutex_unlock(&debug_mutex); -out: - return; + debug_info_put(id); } EXPORT_SYMBOL(debug_unregister); @@ -758,62 +950,59 @@ 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) +static int debug_set_size(debug_info_t *id, int nr_areas, int pages_per_area) { + debug_info_t *new_id; unsigned long flags; - debug_entry_t *** new_areas; - int rc=0; - if(!id || (nr_areas <= 0) || (pages_per_area < 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; + + new_id = debug_info_alloc("", pages_per_area, nr_areas, id->buf_size, + id->level, ALL_AREAS); + if (!new_id) { + pr_info("Allocating memory for %i pages failed\n", + pages_per_area); + return -ENOMEM; } - 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; + + spin_lock_irqsave(&id->lock, flags); + debug_events_append(new_id, id); + debug_areas_swap(new_id, id); + debug_info_free(new_id); + spin_unlock_irqrestore(&id->lock, flags); + pr_info("%s: set new size (%i pages)\n", id->name, pages_per_area); + + return 0; } -/* - * debug_set_level: - * - set actual debug level +/** + * debug_set_level() - Sets new actual debug level if new_level is valid. + * + * @id: handle for debug log + * @new_level: new debug level + * + * Return: + * none */ - -void -debug_set_level(debug_info_t* id, int new_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)) { + + if (!id) + return; + + if (new_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); + id->name, new_level, 0, DEBUG_MAX_LEVEL); + return; + } + + spin_lock_irqsave(&id->lock, flags); + id->level = new_level; + spin_unlock_irqrestore(&id->lock, flags); } EXPORT_SYMBOL(debug_set_level); @@ -821,12 +1010,10 @@ 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) +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)){ + > (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) % @@ -838,9 +1025,7 @@ proceed_active_entry(debug_info_t * id) * proceed_active_area: * - set active area to next in the ring buffer */ - -static inline void -proceed_active_area(debug_info_t * id) +static inline void proceed_active_area(debug_info_t *id) { id->active_area++; id->active_area = id->active_area % id->nr_areas; @@ -849,13 +1034,47 @@ proceed_active_area(debug_info_t * id) /* * get_active_entry: */ - -static inline debug_entry_t* -get_active_entry(debug_info_t * id) +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]); + [id->active_pages[id->active_area]]) + + id->active_entries[id->active_area]); +} + +/* Swap debug areas of a and b. */ +static void debug_areas_swap(debug_info_t *a, debug_info_t *b) +{ + swap(a->nr_areas, b->nr_areas); + swap(a->pages_per_area, b->pages_per_area); + swap(a->areas, b->areas); + swap(a->active_area, b->active_area); + swap(a->active_pages, b->active_pages); + swap(a->active_entries, b->active_entries); +} + +/* Append all debug events in active area from source to destination log. */ +static void debug_events_append(debug_info_t *dest, debug_info_t *src) +{ + debug_entry_t *from, *to, *last; + + if (!src->areas || !dest->areas) + return; + + /* Loop over all entries in src, starting with oldest. */ + from = get_active_entry(src); + last = from; + do { + if (from->clock != 0LL) { + to = get_active_entry(dest); + memset(to, 0, dest->entry_size); + memcpy(to, from, min(src->entry_size, + dest->entry_size)); + proceed_active_entry(dest); + } + + proceed_active_entry(src); + from = get_active_entry(src); + } while (from != last); } /* @@ -863,22 +1082,27 @@ get_active_entry(debug_info_t * id) * - 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) +static inline void debug_finish_entry(debug_info_t *id, debug_entry_t *active, + int level, int exception) { - active->id.stck = get_tod_clock(); - active->id.fields.cpuid = smp_processor_id(); + unsigned long timestamp; + union tod_clock clk; + + store_tod_clock_ext(&clk); + timestamp = clk.us; + timestamp -= TOD_UNIX_EPOCH >> 12; + active->clock = timestamp; + active->cpu = smp_processor_id(); active->caller = __builtin_return_address(0); - active->id.fields.exception = exception; - active->id.fields.level = level; + active->exception = exception; + active->level = level; proceed_active_entry(id); - if(exception) + if (exception) proceed_active_area(id); } -static int debug_stoppable=1; -static int debug_active=1; +static int debug_stoppable = 1; +static int debug_active = 1; #define CTL_S390DBF_STOPPABLE 5678 #define CTL_S390DBF_ACTIVE 5679 @@ -888,9 +1112,8 @@ static int debug_active=1; * always allow read, allow write only if debug_stoppable is set or * if debug_active is already off */ -static int -s390dbf_procactive(ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +static int s390dbf_procactive(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) { if (!write || debug_stoppable || !debug_active) return proc_dointvec(table, write, buffer, lenp, ppos); @@ -898,45 +1121,51 @@ s390dbf_procactive(ctl_table *table, int write, return 0; } - -static struct ctl_table s390dbf_table[] = { +static const struct ctl_table s390dbf_table[] = { { - .procname = "debug_stoppable", + .procname = "debug_stoppable", .data = &debug_stoppable, .maxlen = sizeof(int), - .mode = S_IRUGO | S_IWUSR, - .proc_handler = proc_dointvec, + .mode = S_IRUGO | S_IWUSR, + .proc_handler = proc_dointvec, }, - { - .procname = "debug_active", + { + .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, + .mode = S_IRUGO | S_IWUSR, + .proc_handler = s390dbf_procactive, }, - { } }; static struct ctl_table_header *s390dbf_sysctl_header; -void -debug_stop_all(void) +/** + * debug_stop_all() - stops the debug feature if stopping is allowed. + * + * Return: + * - none + * + * Currently used in case of a kernel oops. + */ +void debug_stop_all(void) { if (debug_stoppable) debug_active = 0; } EXPORT_SYMBOL(debug_stop_all); +/** + * debug_set_critical() - event/exception functions try lock instead of spin. + * + * Return: + * - none + * + * Currently used in case of stopping all CPUs but the current one. + * Once in this state, functions to write a debug entry for an + * event or exception no longer spin on the debug area lock, + * but only try to get it and fail if they do not get the lock. + */ void debug_set_critical(void) { debug_critical = 1; @@ -946,26 +1175,31 @@ void debug_set_critical(void) * 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 *debug_event_common(debug_info_t *id, int level, const void *buf, + int len) { - unsigned long flags; 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 + } else { spin_lock_irqsave(&id->lock, flags); - active = get_active_entry(id); - memset(DEBUG_DATA(active), 0, id->buf_size); - memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); - debug_finish_entry(id, active, level, 0); - spin_unlock_irqrestore(&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); @@ -974,26 +1208,31 @@ 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 *debug_exception_common(debug_info_t *id, int level, + const void *buf, int len) { - unsigned long flags; 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 + } else { spin_lock_irqsave(&id->lock, flags); - active = get_active_entry(id); - memset(DEBUG_DATA(active), 0, id->buf_size); - memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); - debug_finish_entry(id, active, level, 1); - spin_unlock_irqrestore(&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); @@ -1001,108 +1240,106 @@ EXPORT_SYMBOL(debug_exception_common); /* * counts arguments in format string for sprintf view */ - -static inline int -debug_count_numargs(char *string) +static inline int debug_count_numargs(char *string) { - int numargs=0; + int numargs = 0; - while(*string) { - if(*string++=='%') + while (*string) { + if (*string++ == '%') numargs++; } - return(numargs); + return numargs; } /* * debug_sprintf_event: */ - -debug_entry_t* -debug_sprintf_event(debug_info_t* id, int level,char *string,...) +debug_entry_t *__debug_sprintf_event(debug_info_t *id, int level, char *string, ...) { - va_list ap; - int numargs,idx; - unsigned long flags; debug_sprintf_entry_t *curr_event; debug_entry_t *active; + unsigned long flags; + int numargs, idx; + va_list ap; - if((!id) || (level > id->level)) - return NULL; if (!debug_active || !id->areas) return NULL; - numargs=debug_count_numargs(string); + numargs = debug_count_numargs(string); if (debug_critical) { if (!spin_trylock_irqsave(&id->lock, flags)) return NULL; - } else + } 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); + 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); +EXPORT_SYMBOL(__debug_sprintf_event); /* * debug_sprintf_exception: */ - -debug_entry_t* -debug_sprintf_exception(debug_info_t* id, int level,char *string,...) +debug_entry_t *__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...) { - va_list ap; - int numargs,idx; - unsigned long flags; debug_sprintf_entry_t *curr_event; debug_entry_t *active; + unsigned long flags; + int numargs, idx; + va_list ap; - if((!id) || (level > id->level)) - return NULL; if (!debug_active || !id->areas) return NULL; - numargs=debug_count_numargs(string); + numargs = debug_count_numargs(string); if (debug_critical) { if (!spin_trylock_irqsave(&id->lock, flags)) return NULL; - } else + } 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); + 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); +EXPORT_SYMBOL(__debug_sprintf_exception); -/* - * debug_register_view: +/** + * debug_register_view() - registers new debug view and creates debugfs + * dir entry + * + * @id: handle for debug log + * @view: pointer to debug view struct + * + * Return: + * - 0 : ok + * - < 0: Error */ - -int -debug_register_view(debug_info_t * id, struct debug_view *view) +int debug_register_view(debug_info_t *id, struct debug_view *view) { - int rc = 0; - int i; unsigned long flags; - umode_t mode; struct dentry *pde; + umode_t mode; + int rc = 0; + int i; if (!id) goto out; @@ -1112,40 +1349,41 @@ debug_register_view(debug_info_t * id, struct debug_view *view) 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; - } + id, &debug_file_ops); 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) + if (rc) { + pr_err("Registering view %s/%s would exceed the maximum " + "number of views %i\n", id->name, view->name, i); debugfs_remove(pde); + } out: return rc; } EXPORT_SYMBOL(debug_register_view); -/* - * debug_unregister_view: +/** + * debug_unregister_view() - unregisters debug view and removes debugfs + * dir entry + * + * @id: handle for debug log + * @view: pointer to debug view struct + * + * Return: + * - 0 : ok + * - < 0: Error */ - -int -debug_unregister_view(debug_info_t * id, struct debug_view *view) +int debug_unregister_view(debug_info_t *id, struct debug_view *view) { struct dentry *dentry = NULL; unsigned long flags; @@ -1158,9 +1396,9 @@ debug_unregister_view(debug_info_t * id, struct debug_view *view) if (id->views[i] == view) break; } - if (i == DEBUG_MAX_VIEWS) + if (i == DEBUG_MAX_VIEWS) { rc = -1; - else { + } else { dentry = id->debugfs_entries[i]; id->views[i] = NULL; id->debugfs_entries[i] = NULL; @@ -1172,36 +1410,28 @@ out: } EXPORT_SYMBOL(debug_unregister_view); -static inline char * -debug_get_user_string(const char __user *user_buf, size_t user_len) +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); - } + char *buffer; + + buffer = memdup_user_nul(user_buf, user_len); + if (IS_ERR(buffer)) + return buffer; /* got the string, now strip linefeed. */ if (buffer[user_len - 1] == '\n') buffer[user_len - 1] = 0; - else - buffer[user_len] = 0; - return buffer; + return buffer; } -static inline int -debug_get_uint(char *buf) +static inline int debug_get_uint(char *buf) { int rc; buf = skip_spaces(buf); rc = simple_strtoul(buf, &buf, 10); - if(*buf){ + if (*buf) rc = -EINVAL; - } return rc; } @@ -1214,43 +1444,41 @@ debug_get_uint(char *buf) * prints out actual debug level */ -static int -debug_prolog_pages_fn(debug_info_t * id, - struct debug_view *view, char *out_buf) +static int debug_prolog_pages_fn(debug_info_t *id, struct debug_view *view, + char *out_buf, size_t out_buf_size) { - return sprintf(out_buf, "%i\n", id->pages_per_area); + return scnprintf(out_buf, out_buf_size, "%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) +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; - int rc,new_pages; if (user_len > 0x10000) - user_len = 0x10000; - if (*offset != 0){ + user_len = 0x10000; + if (*offset != 0) { rc = -EPIPE; goto out; } - str = debug_get_user_string(user_buf,user_len); - if(IS_ERR(str)){ + 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){ + if (new_pages < 0) { rc = -EINVAL; goto free_str; } - rc = debug_set_size(id,id->nr_areas, new_pages); - if(rc != 0){ + rc = debug_set_size(id, id->nr_areas, new_pages); + if (rc != 0) { rc = -EINVAL; goto free_str; } @@ -1265,54 +1493,48 @@ out: /* * prints out actual debug level */ - -static int -debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf) +static int debug_prolog_level_fn(debug_info_t *id, struct debug_view *view, + char *out_buf, size_t out_buf_size) { int rc = 0; - if(id->level == DEBUG_OFF_LEVEL) { - rc = sprintf(out_buf,"-\n"); - } - else { - rc = sprintf(out_buf, "%i\n", id->level); - } + if (id->level == DEBUG_OFF_LEVEL) + rc = scnprintf(out_buf, out_buf_size, "-\n"); + else + rc = scnprintf(out_buf, out_buf_size, "%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) +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; - int rc,new_level; if (user_len > 0x10000) - user_len = 0x10000; - if (*offset != 0){ + user_len = 0x10000; + if (*offset != 0) { rc = -EPIPE; goto out; } - str = debug_get_user_string(user_buf,user_len); - if(IS_ERR(str)){ + str = debug_get_user_string(user_buf, user_len); + if (IS_ERR(str)) { rc = PTR_ERR(str); goto out; } - if(str[0] == '-'){ + 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_warning("%s is not a valid level for a debug " - "feature\n", 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); @@ -1325,208 +1547,173 @@ out: return rc; /* number of input characters */ } - /* * flushes debug areas */ - -static void debug_flush(debug_info_t* id, int area) +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++) { + 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); - } + 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; + } 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); + 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 + * 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) +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; + char input_buf[1]; + int rc = user_len; if (user_len > 0x10000) - user_len = 0x10000; - if (*offset != 0){ + user_len = 0x10000; + if (*offset != 0) { rc = -EPIPE; - goto out; + 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; } - 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; + *offset += user_len; + return rc; /* number of input characters */ } /* * 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) +static int debug_hex_ascii_format_fn(debug_info_t *id, struct debug_view *view, + char *out_buf, size_t out_buf_size, 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, "| "); + rc += scnprintf(out_buf + rc, out_buf_size - rc, + "%02x ", ((unsigned char *)in_buf)[i]); + } + rc += scnprintf(out_buf + rc, out_buf_size - 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); + rc += scnprintf(out_buf + rc, out_buf_size - rc, "%c", c); else - rc += sprintf(out_buf + rc, "."); + rc += scnprintf(out_buf + rc, out_buf_size - rc, "."); } - rc += sprintf(out_buf + rc, "\n"); + rc += scnprintf(out_buf + rc, out_buf_size - 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) +int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view, + int area, debug_entry_t *entry, char *out_buf, + size_t out_buf_size) { - struct timespec time_spec; - char *except_str; + unsigned long sec, usec; unsigned long caller; - int rc = 0; unsigned int level; + char *except_str; + int rc = 0; - level = entry->id.fields.level; - stck_to_timespec(entry->id.stck, &time_spec); + level = entry->level; + sec = entry->clock; + usec = do_div(sec, USEC_PER_SEC); - if (entry->id.fields.exception) + if (entry->exception) except_str = "*"; else except_str = "-"; - caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN; - rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p ", - area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level, - except_str, entry->id.fields.cpuid, (void *) caller); + caller = (unsigned long) entry->caller; + rc += scnprintf(out_buf, out_buf_size, "%02i %011ld:%06lu %1u %1s %04u %px ", + area, sec, usec, level, except_str, + entry->cpu, (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 + * prints debug data sprintf-formatted: + * debug_sprintf_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 debug_sprintf_format_fn(debug_info_t *id, struct debug_view *view, + char *out_buf, size_t out_buf_size, const char *inbuf) { - int num_longs, num_used_args = 0,i, rc = 0; + debug_sprintf_entry_t *curr_event = (debug_sprintf_entry_t *)inbuf; + 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); + num_longs = id->buf_size / sizeof(long); - if(num_longs < 1) + if (num_longs < 1) goto out; /* bufsize of entry too small */ - if(num_longs == 1) { + if (num_longs == 1) { /* no args, we use only the string */ - strcpy(out_buf, curr_event->string); - rc = strlen(curr_event->string); + rc = strscpy(out_buf, curr_event->string, out_buf_size); + if (rc == -E2BIG) + rc = out_buf_size; goto out; } /* number of arguments used for sprintf (without the format string) */ - num_used_args = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1)); + num_used_args = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1)); - memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int)); + memset(index, 0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int)); - for(i = 0; i < num_used_args; i++) + 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]]); - + rc = scnprintf(out_buf, out_buf_size, + 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; } +EXPORT_SYMBOL(debug_sprintf_format_fn); /* * debug_init: @@ -1534,7 +1721,7 @@ out: */ static int __init debug_init(void) { - s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table); + s390dbf_sysctl_header = register_sysctl("s390dbf", s390dbf_table); mutex_lock(&debug_mutex); debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT, NULL); initialized = 1; |
