/* * Information interface for ALSA driver * Copyright (c) by Jaroslav Kysela <perex@perex.cz> * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include <linux/init.h> #include <linux/time.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/module.h> #include <sound/core.h> #include <sound/minors.h> #include <sound/info.h> #include <linux/utsname.h> #include <linux/proc_fs.h> #include <linux/mutex.h> #include <stdarg.h> /* * */ #ifdef CONFIG_PROC_FS int snd_info_check_reserved_words(const char *str) { static char *reserved[] = { "version", "meminfo", "memdebug", "detect", "devices", "oss", "cards", "timers", "synth", "pcm", "seq", NULL }; char **xstr = reserved; while (*xstr) { if (!strcmp(*xstr, str)) return 0; xstr++; } if (!strncmp(str, "card", 4)) return 0; return 1; } static DEFINE_MUTEX(info_mutex); struct snd_info_private_data { struct snd_info_buffer *rbuffer; struct snd_info_buffer *wbuffer; struct snd_info_entry *entry; void *file_private_data; }; static int snd_info_version_init(void); static int snd_info_version_done(void); static void snd_info_disconnect(struct snd_info_entry *entry); /* resize the proc r/w buffer */ static int resize_info_buffer(struct snd_info_buffer *buffer, unsigned int nsize) { char *nbuf; nsize = PAGE_ALIGN(nsize); nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL | __GFP_ZERO); if (! nbuf) return -ENOMEM; buffer->buffer = nbuf; buffer->len = nsize; return 0; } /** * snd_iprintf - printf on the procfs buffer * @buffer: the procfs buffer * @fmt: the printf format * * Outputs the string on the procfs buffer just like printf(). * * Return: The size of output string, or a negative error code. */ int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...) { va_list args; int len, res; int err = 0; might_sleep(); if (buffer->stop || buffer->error) return 0; len = buffer->len - buffer->size; va_start(args, fmt); for (;;) { va_list ap; va_copy(ap, args); res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap); va_end(ap); if (res < len) break; err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE); if (err < 0) break; len = buffer->len - buffer->size; } va_end(args); if (err < 0) return err; buffer->curr += res; buffer->size += res; return res; } EXPORT_SYMBOL(snd_iprintf); /* */ static struct proc_dir_entry *snd_proc_root; struct snd_info_entry *snd_seq_root; EXPORT_SYMBOL(snd_seq_root); #ifdef CONFIG_SND_OSSEMUL struct snd_info_entry *snd_oss_root; #endif static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig) { struct snd_info_private_data *data; struct snd_info_entry *entry; loff_t ret = -EINVAL, size; data = file->private_data; entry = data->entry; mutex_lock(&entry->access); if (entry->content == SNDRV_INFO_CONTENT_DATA && entry->c.ops->llseek) { offset = entry->c.ops->llseek(entry, data->file_private_data, file, offset, orig); goto out; } if (entry->content == SNDRV_INFO_CONTENT_DATA) size = entry->size; else size = 0; switch (orig) { case SEEK_SET: break; case SEEK_CUR: offset += file->f_pos; break; case SEEK_END: if (!size) goto out; offset += size; break; default: goto out; } if (offset < 0) goto out; if (size && offset > size) offset = size; file->f_pos = offset; ret = offset; out: mutex_unlock(&entry->access); return ret; } static ssize_t snd_info_entry_read(struct file *file, char __user *buffer, size_t count, loff_t * offset) { struct snd_info_private_data *data; struct snd_info_entry *entry; struct snd_info_buffer *buf; size_t size = 0; loff_t pos; data = file->private_data; if (snd_BUG_ON(!data)) return -ENXIO; pos = *offset; if (pos < 0 || (long) pos != pos || (ssize_t) count < 0) return -EIO; if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos) return -EIO; entry = data->entry; switch (entry->content) { case SNDRV_INFO_CONTENT_TEXT: buf = data->rbuffer; if (buf == NULL) return -EIO; if (pos >= buf->size) return 0; size = buf->size - pos; size = min(count, size); if (copy_to_user(buffer, buf->buffer + pos, size)) return -EFAULT; break; case SNDRV_INFO_CONTENT_DATA: if (pos >= entry->size) return 0; if (entry->c.ops->read) { size = entry->size - pos; size = min(count, size); size = entry->c.ops->read(entry, data->file_private_data, file, buffer, size, pos); } break; } if ((ssize_t) size > 0) *offset = pos + size; return size; } static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer, size_t count, loff_t * offset) { struct snd_info_private_data *data; struct snd_info_entry *entry; struct snd_info_buffer *buf; ssize_t size = 0; loff_t pos; data = file->private_data; if (snd_BUG_ON(!data)) return -ENXIO; entry = data->entry; pos = *offset; if (pos < 0 || (long) pos != pos || (ssize_t) count < 0) return -EIO; if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos) return -EIO; switch (entry->content) { case SNDRV_INFO_CONTENT_TEXT: buf = data->wbuffer; if (buf == NULL) return -EIO; mutex_lock(&entry->access); if (pos + count >= buf->len) { if (resize_info_buffer(buf, pos + count)) { mutex_unlock(&entry->access); return -ENOMEM; } } if (copy_from_user(buf->buffer + pos, buffer, count)) { mutex_unlock(&entry->access); return -EFAULT; } buf->size = pos + count; mutex_unlock(&entry->access); size = count; break; case SNDRV_INFO_CONTENT_DATA: if (entry->c.ops->write && count > 0) { size_t maxsize = entry->size - pos; count = min(count, maxsize); size = entry->c.ops->write(entry, data->file_private_data, file, buffer, count, pos); } break; } if ((ssize_t) size > 0) *offset = pos + size; return size; } static int snd_info_entry_open(struct inode *inode, struct file *file) { struct snd_info_entry *entry; struct snd_info_private_data *data; struct snd_info_buffer *buffer; int mode, err; mutex_lock(&info_mutex); entry = PDE_DATA(inode); if (entry == NULL || ! entry->p) { mutex_unlock(&info_mutex); return -ENODEV; } if (!try_module_get(entry->module)) { err = -EFAULT; goto __error1; } mode = file->f_flags & O_ACCMODE; if (mode == O_RDONLY || mode == O_RDWR) { if ((entry->content == SNDRV_INFO_CONTENT_DATA && entry->c.ops->read == NULL)) { err = -ENODEV; goto __error; } } if (mode == O_WRONLY || mode == O_RDWR) { if ((entry->content == SNDRV_INFO_CONTENT_DATA && entry->c.ops->write == NULL)) { err = -ENODEV; goto __error; } } data = kzalloc(sizeof(*data), GFP_KERNEL); if (data == NULL) { err = -ENOMEM; goto __error; } data->entry = entry; switch (entry->content) { case SNDRV_INFO_CONTENT_TEXT: if (mode == O_RDONLY || mode == O_RDWR) { buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); if (buffer == NULL) goto __nomem; data->rbuffer = buffer; buffer->len = PAGE_SIZE; buffer->buffer = kzalloc(buffer->len, GFP_KERNEL); if (buffer->buffer == NULL) goto __nomem; } if (mode == O_WRONLY || mode == O_RDWR) { buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); if (buffer == NULL) goto __nomem; data->wbuffer = buffer; buffer->len = PAGE_SIZE; buffer->buffer = kmalloc(buffer->len, GFP_KERNEL); if (buffer->buffer == NULL) goto __nomem; } break; case SNDRV_INFO_CONTENT_DATA: /* data */ if (entry->c.ops->open) { if ((err = entry->c.ops->open(entry, mode, &data->file_private_data)) < 0) { kfree(data); goto __error; } } break; } file->private_data = data; mutex_unlock(&info_mutex); if (entry->content == SNDRV_INFO_CONTENT_TEXT && (mode == O_RDONLY || mode == O_RDWR)) { if (entry->c.text.read) { mutex_lock(&entry->access); entry->c.text.read(entry, data->rbuffer); mutex_unlock(&entry->access); } } return 0; __nomem: if (data->rbuffer) { kfree(data->rbuffer->buffer); kfree(data->rbuffer); } if (data->wbuffer) { kfree(data->wbuffer->buffer); kfree(data->wbuffer); } kfree(data); err = -ENOMEM; __error: module_put(entry->module); __error1: mutex_unlock(&info_mutex); return err; } static int snd_info_entry_release(struct inode *inode, struct file *file) { struct snd_info_entry *entry; struct snd_info_private_data *data; int mode; mode = file->f_flags & O_ACCMODE; data = file->private_data; entry = data->entry; switch (entry->content) { case SNDRV_INFO_CONTENT_TEXT: if (data->rbuffer) { kfree(data->rbuffer->buffer); kfree(data->rbuffer); } if (data->wbuffer) { if (entry->c.text.write) { entry->c.text.write(entry, data->wbuffer); if (data->wbuffer->error) { if (entry->card) dev_warn(entry->card->dev, "info: data write error to %s (%i)\n", entry->name, data->wbuffer->error); else pr_warn("ALSA: info: data write error to %s (%i)\n", entry->name, data->wbuffer->error); } } kfree(data->wbuffer->buffer); kfree(data->wbuffer); } break; case SNDRV_INFO_CONTENT_DATA: if (entry->c.ops->release) entry->c.ops->release(entry, mode, data->file_private_data); break; } module_put(entry->module); kfree(data); return 0; } static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait) { struct snd_info_private_data *data; struct snd_info_entry *entry; unsigned int mask; data = file->private_data; if (data == NULL) return 0; entry = data->entry; mask = 0; switch (entry->content) { case SNDRV_INFO_CONTENT_DATA: if (entry->c.ops->poll) return entry->c.ops->poll(entry, data->file_private_data, file, wait); if (entry->c.ops->read) mask |= POLLIN | POLLRDNORM; if (entry->c.ops->write) mask |= POLLOUT | POLLWRNORM; break; } return mask; } static long snd_info_entry_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct snd_info_private_data *data; struct snd_info_entry *entry; data = file->private_data; if (data == NULL) return 0; entry = data->entry; switch (entry->content) { case SNDRV_INFO_CONTENT_DATA: if (entry->c.ops->ioctl) return entry->c.ops->ioctl(entry, data->file_private_data, file, cmd, arg); break; } return -ENOTTY; } static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma) { struct inode *inode = file_inode(file); struct snd_info_private_data *data; struct snd_info_entry *entry; data = file->private_data; if (data == NULL) return 0; entry = data->entry; switch (entry->content) { case SNDRV_INFO_CONTENT_DATA: if (entry->c.ops->mmap) return entry->c.ops->mmap(entry, data->file_private_data, inode, file, vma); break; } return -ENXIO; } static const struct file_operations snd_info_entry_operations = { .owner = THIS_MODULE, .llseek = snd_info_entry_llseek, .read = snd_info_entry_read, .write = snd_info_entry_write, .poll = snd_info_entry_poll, .unlocked_ioctl = snd_info_entry_ioctl, .mmap = snd_info_entry_mmap, .open = snd_info_entry_open, .release = snd_info_entry_release, }; int __init snd_info_init(void) { struct proc_dir_entry *p; p = proc_mkdir("asound", NULL); if (p == NULL) return -ENOMEM; snd_proc_root = p; #ifdef CONFIG_SND_OSSEMUL { struct snd_info_entry *entry; if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL) return -ENOMEM; entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); return -ENOMEM; } snd_oss_root = entry; } #endif #if IS_ENABLED(CONFIG_SND_SEQUENCER) { struct snd_info_entry *entry; if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL) return -ENOMEM; entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); return -ENOMEM; } snd_seq_root = entry; } #endif snd_info_version_init(); snd_minor_info_init(); snd_minor_info_oss_init(); snd_card_info_init(); return 0; } int __exit snd_info_done(void) { snd_card_info_done(); snd_minor_info_oss_done(); snd_minor_info_done(); snd_info_version_done(); if (snd_proc_root) { #if IS_ENABLED(CONFIG_SND_SEQUENCER) snd_info_free_entry(snd_seq_root); #endif #ifdef CONFIG_SND_OSSEMUL snd_info_free_entry(snd_oss_root); #endif proc_remove(snd_proc_root); } return 0; } /* */ /* * create a card proc file * called from init.c */ int snd_info_card_create(struct snd_card *card) { char str[8]; struct snd_info_entry *entry; if (snd_BUG_ON(!card)) return -ENXIO; sprintf(str, "card%i", card->number); if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL) return -ENOMEM; entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); return -ENOMEM; } card->proc_root = entry; return 0; } /* * register the card proc file * called from init.c */ int snd_info_card_register(struct snd_card *card) { struct proc_dir_entry *p; if (snd_BUG_ON(!card)) return -ENXIO; if (!strcmp(card->id, card->proc_root->name)) return 0; p = proc_symlink(card->id, snd_proc_root, card->proc_root->name); if (p == NULL) return -ENOMEM; card->proc_root_link = p; return 0; } /* * called on card->id change */ void snd_info_card_id_change(struct snd_card *card) { mutex_lock(&info_mutex); if (card->proc_root_link) { proc_remove(card->proc_root_link); card->proc_root_link = NULL; } if (strcmp(card->id, card->proc_root->name)) card->proc_root_link = proc_symlink(card->id, snd_proc_root, card->proc_root->name); mutex_unlock(&info_mutex); } /* * de-register the card proc file * called from init.c */ void snd_info_card_disconnect(struct snd_card *card) { if (!card) return; mutex_lock(&info_mutex); proc_remove(card->proc_root_link); card->proc_root_link = NULL; if (card->proc_root) snd_info_disconnect(card->proc_root); mutex_unlock(&info_mutex); } /* * release the card proc file resources * called from init.c */ int snd_info_card_free(struct snd_card *card) { if (!card) return 0; snd_info_free_entry(card->proc_root); card->proc_root = NULL; return 0; } /** * snd_info_get_line - read one line from the procfs buffer * @buffer: the procfs buffer * @line: the buffer to store * @len: the max. buffer size * * Reads one line from the buffer and stores the string. * * Return: Zero if successful, or 1 if error or EOF. */ int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len) { int c = -1; if (snd_BUG_ON(!buffer || !buffer->buffer)) return 1; if (len <= 0 || buffer->stop || buffer->error) return 1; while (!buffer->stop) { c = buffer->buffer[buffer->curr++]; if (buffer->curr >= buffer->size) buffer->stop = 1; if (c == '\n') break; if (len > 1) { len--; *line++ = c; } } *line = '\0'; return 0; } EXPORT_SYMBOL(snd_info_get_line); /** * snd_info_get_str - parse a string token * @dest: the buffer to store the string token * @src: the original string * @len: the max. length of token - 1 * * Parses the original string and copy a token to the given * string buffer. * * Return: The updated pointer of the original string so that * it can be used for the next call. */ const char *snd_info_get_str(char *dest, const char *src, int len) { int c; while (*src == ' ' || *src == '\t') src++; if (*src == '"' || *src == '\'') { c = *src++; while (--len > 0 && *src && *src != c) { *dest++ = *src++; } if (*src == c) src++; } else { while (--len > 0 && *src && *src != ' ' && *src != '\t') { *dest++ = *src++; } } *dest = 0; while (*src == ' ' || *src == '\t') src++; return src; } EXPORT_SYMBOL(snd_info_get_str); /** * snd_info_create_entry - create an info entry * @name: the proc file name * * Creates an info entry with the given file name and initializes as * the default state. * * Usually called from other functions such as * snd_info_create_card_entry(). * * Return: The pointer of the new instance, or %NULL on failure. */ static struct snd_info_entry *snd_info_create_entry(const char *name) { struct snd_info_entry *entry; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (entry == NULL) return NULL; entry->name = kstrdup(name, GFP_KERNEL); if (entry->name == NULL) { kfree(entry); return NULL; } entry->mode = S_IFREG | S_IRUGO; entry->content = SNDRV_INFO_CONTENT_TEXT; mutex_init(&entry->access); INIT_LIST_HEAD(&entry->children); INIT_LIST_HEAD(&entry->list); return entry; } /** * snd_info_create_module_entry - create an info entry for the given module * @module: the module pointer * @name: the file name * : the parent directory * * Creates a new info entry and assigns it to the given module. * * Return: The pointer of the new instance, or %NULL on failure. */ struct snd_info_entry *snd_info_create_module_entry(struct module * module, const char *name, struct snd_info_entry *parent) { struct snd_info_entry *entry = snd_info_create_entry(name); if (entry) { entry->module = module; entry->parent = parent; } return entry; } EXPORT_SYMBOL(snd_info_create_module_entry); /** * snd_info_create_card_entry - create an info entry for the given card * @card: the card instance * @name: the file name * : the parent directory * * Creates a new info entry and assigns it to the given card. * * Return: The pointer of the new instance, or %NULL on failure. */ struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card, const char *name, struct snd_info_entry * parent) { struct snd_info_entry *entry = snd_info_create_entry(name); if (entry) { entry->module = card->module; entry->card = card; entry->parent = parent; } return entry; } EXPORT_SYMBOL(snd_info_create_card_entry); static void snd_info_disconnect(struct snd_info_entry *entry) { struct list_head *p, *n; struct proc_dir_entry *root; list_for_each_safe(p, n, &entry->children) { snd_info_disconnect(list_entry(p, struct snd_info_entry, list)); } if (! entry->p) return; list_del_init(&entry->list); root = entry->parent == NULL ? snd_proc_root : entry->parent->p; snd_BUG_ON(!root); proc_remove(entry->p); entry->p = NULL; } static int snd_info_dev_free_entry(struct snd_device *device) { struct snd_info_entry *entry = device->device_data; snd_info_free_entry(entry); return 0; } static int snd_info_dev_register_entry(struct snd_device *device) { struct snd_info_entry *entry = device->device_data; return snd_info_register(entry); } /** * snd_card_proc_new - create an info entry for the given card * @card: the card instance * @name: the file name * @entryp: the pointer to store the new info entry * * Creates a new info entry and assigns it to the given card. * Unlike snd_info_create_card_entry(), this function registers the * info entry as an ALSA device component, so that it can be * unregistered/released without explicit call. * Also, you don't have to register this entry via snd_info_register(), * since this will be registered by snd_card_register() automatically. * * The parent is assumed as card->proc_root. * * For releasing this entry, use snd_device_free() instead of * snd_info_free_entry(). * * Return: Zero if successful, or a negative error code on failure. */ int snd_card_proc_new(struct snd_card *card, const char *name, struct snd_info_entry **entryp) { static struct snd_device_ops ops = { .dev_free = snd_info_dev_free_entry, .dev_register = snd_info_dev_register_entry, /* disconnect is done via snd_info_card_disconnect() */ }; struct snd_info_entry *entry; int err; entry = snd_info_create_card_entry(card, name, card->proc_root); if (! entry) return -ENOMEM; if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) { snd_info_free_entry(entry); return err; } if (entryp) *entryp = entry; return 0; } EXPORT_SYMBOL(snd_card_proc_new); /** * snd_info_free_entry - release the info entry * @entry: the info entry * * Releases the info entry. Don't call this after registered. */ void snd_info_free_entry(struct snd_info_entry * entry) { if (entry == NULL) return; if (entry->p) { mutex_lock(&info_mutex); snd_info_disconnect(entry); mutex_unlock(&info_mutex); } kfree(entry->name); if (entry->private_free) entry->private_free(entry); kfree(entry); } EXPORT_SYMBOL(snd_info_free_entry); /** * snd_info_register - register the info entry * @entry: the info entry * * Registers the proc info entry. * * Return: Zero if successful, or a negative error code on failure. */ int snd_info_register(struct snd_info_entry * entry) { struct proc_dir_entry *root, *p = NULL; if (snd_BUG_ON(!entry)) return -ENXIO; root = entry->parent == NULL ? snd_proc_root : entry->parent->p; mutex_lock(&info_mutex); if (S_ISDIR(entry->mode)) { p = proc_mkdir_mode(entry->name, entry->mode, root); if (!p) { mutex_unlock(&info_mutex); return -ENOMEM; } } else { p = proc_create_data(entry->name, entry->mode, root, &snd_info_entry_operations, entry); if (!p) { mutex_unlock(&info_mutex); return -ENOMEM; } proc_set_size(p, entry->size); } entry->p = p; if (entry->parent) list_add_tail(&entry->list, &entry->parent->children); mutex_unlock(&info_mutex); return 0; } EXPORT_SYMBOL(snd_info_register); /* */ static struct snd_info_entry *snd_info_version_entry; static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer) { snd_iprintf(buffer, "Advanced Linux Sound Architecture Driver Version k%s.\n", init_utsname()->release); } static int __init snd_info_version_init(void) { struct snd_info_entry *entry; entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL); if (entry == NULL) return -ENOMEM; entry->c.text.read = snd_info_version_read; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); return -ENOMEM; } snd_info_version_entry = entry; return 0; } static int __exit snd_info_version_done(void) { snd_info_free_entry(snd_info_version_entry); return 0; } #endif /* CONFIG_PROC_FS */