memory.c
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/* * Copyright (c) by Jaroslav Kysela <perex@suse.cz> * * Memory allocation helpers. * * * 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 <sound/driver.h>#include <asm/io.h>#include <asm/uaccess.h>#include <linux/init.h>#include <linux/slab.h>#include <linux/time.h>#include <linux/pci.h>#include <sound/core.h>#include <sound/info.h>/* * memory allocation helpers and debug routines */#ifdef CONFIG_SND_DEBUG_MEMORYstruct snd_alloc_track { unsigned long magic; void *caller; size_t size; struct list_head list; long data[0];};#define snd_alloc_track_entry(obj) (struct snd_alloc_track *)((char*)obj - (unsigned long)((struct snd_alloc_track *)0)->data)static long snd_alloc_kmalloc;static long snd_alloc_vmalloc;static LIST_HEAD(snd_alloc_kmalloc_list);static LIST_HEAD(snd_alloc_vmalloc_list);static spinlock_t snd_alloc_kmalloc_lock = SPIN_LOCK_UNLOCKED;static spinlock_t snd_alloc_vmalloc_lock = SPIN_LOCK_UNLOCKED;#define KMALLOC_MAGIC 0x87654321#define VMALLOC_MAGIC 0x87654320static snd_info_entry_t *snd_memory_info_entry;void snd_memory_init(void){ snd_alloc_kmalloc = 0; snd_alloc_vmalloc = 0;}void snd_memory_done(void){ struct list_head *head; struct snd_alloc_track *t; if (snd_alloc_kmalloc > 0) snd_printk(KERN_ERR "Not freed snd_alloc_kmalloc = %li\n", snd_alloc_kmalloc); if (snd_alloc_vmalloc > 0) snd_printk(KERN_ERR "Not freed snd_alloc_vmalloc = %li\n", snd_alloc_vmalloc); list_for_each_prev(head, &snd_alloc_kmalloc_list) { t = list_entry(head, struct snd_alloc_track, list); if (t->magic != KMALLOC_MAGIC) { snd_printk(KERN_ERR "Corrupted kmalloc\n"); break; } snd_printk(KERN_ERR "kmalloc(%ld) from %p not freed\n", (long) t->size, t->caller); } list_for_each_prev(head, &snd_alloc_vmalloc_list) { t = list_entry(head, struct snd_alloc_track, list); if (t->magic != VMALLOC_MAGIC) { snd_printk(KERN_ERR "Corrupted vmalloc\n"); break; } snd_printk(KERN_ERR "vmalloc(%ld) from %p not freed\n", (long) t->size, t->caller); }}void *__snd_kmalloc(size_t size, int flags, void *caller){ unsigned long cpu_flags; struct snd_alloc_track *t; void *ptr; ptr = snd_wrapper_kmalloc(size + sizeof(struct snd_alloc_track), flags); if (ptr != NULL) { t = (struct snd_alloc_track *)ptr; t->magic = KMALLOC_MAGIC; t->caller = caller; spin_lock_irqsave(&snd_alloc_kmalloc_lock, cpu_flags); list_add_tail(&t->list, &snd_alloc_kmalloc_list); spin_unlock_irqrestore(&snd_alloc_kmalloc_lock, cpu_flags); t->size = size; snd_alloc_kmalloc += size; ptr = t->data; } return ptr;}#define _snd_kmalloc(size, flags) __snd_kmalloc((size), (flags), __builtin_return_address(0));void *snd_hidden_kmalloc(size_t size, int flags){ return _snd_kmalloc(size, flags);}void *snd_hidden_kcalloc(size_t n, size_t size, int flags){ void *ret = NULL; if (n != 0 && size > INT_MAX / n) return ret; ret = _snd_kmalloc(n * size, flags); if (ret) memset(ret, 0, n * size); return ret;}void snd_hidden_kfree(const void *obj){ unsigned long flags; struct snd_alloc_track *t; if (obj == NULL) { snd_printk(KERN_WARNING "null kfree (called from %p)\n", __builtin_return_address(0)); return; } t = snd_alloc_track_entry(obj); if (t->magic != KMALLOC_MAGIC) { snd_printk(KERN_WARNING "bad kfree (called from %p)\n", __builtin_return_address(0)); return; } spin_lock_irqsave(&snd_alloc_kmalloc_lock, flags); list_del(&t->list); spin_unlock_irqrestore(&snd_alloc_kmalloc_lock, flags); t->magic = 0; snd_alloc_kmalloc -= t->size; obj = t; snd_wrapper_kfree(obj);}void *snd_hidden_vmalloc(unsigned long size){ void *ptr; ptr = snd_wrapper_vmalloc(size + sizeof(struct snd_alloc_track)); if (ptr) { struct snd_alloc_track *t = (struct snd_alloc_track *)ptr; t->magic = VMALLOC_MAGIC; t->caller = __builtin_return_address(0); spin_lock(&snd_alloc_vmalloc_lock); list_add_tail(&t->list, &snd_alloc_vmalloc_list); spin_unlock(&snd_alloc_vmalloc_lock); t->size = size; snd_alloc_vmalloc += size; ptr = t->data; } return ptr;}void snd_hidden_vfree(void *obj){ struct snd_alloc_track *t; if (obj == NULL) { snd_printk(KERN_WARNING "null vfree (called from %p)\n", __builtin_return_address(0)); return; } t = snd_alloc_track_entry(obj); if (t->magic != VMALLOC_MAGIC) { snd_printk(KERN_ERR "bad vfree (called from %p)\n", __builtin_return_address(0)); return; } spin_lock(&snd_alloc_vmalloc_lock); list_del(&t->list); spin_unlock(&snd_alloc_vmalloc_lock); t->magic = 0; snd_alloc_vmalloc -= t->size; obj = t; snd_wrapper_vfree(obj);}static void snd_memory_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer){ snd_iprintf(buffer, "kmalloc: %li bytes\n", snd_alloc_kmalloc); snd_iprintf(buffer, "vmalloc: %li bytes\n", snd_alloc_vmalloc);}int __init snd_memory_info_init(void){ snd_info_entry_t *entry; entry = snd_info_create_module_entry(THIS_MODULE, "meminfo", NULL); if (entry) { entry->c.text.read_size = 256; entry->c.text.read = snd_memory_info_read; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); entry = NULL; } } snd_memory_info_entry = entry; return 0;}int __exit snd_memory_info_done(void){ if (snd_memory_info_entry) snd_info_unregister(snd_memory_info_entry); return 0;}#else#define _snd_kmalloc kmalloc#endif /* CONFIG_SND_DEBUG_MEMORY *//** * snd_kmalloc_strdup - copy the string * @string: the original string * @flags: allocation conditions, GFP_XXX * * Allocates a memory chunk via kmalloc() and copies the string to it. * * Returns the pointer, or NULL if no enoguh memory. */char *snd_kmalloc_strdup(const char *string, int flags){ size_t len; char *ptr; if (!string) return NULL; len = strlen(string) + 1; ptr = _snd_kmalloc(len, flags); if (ptr) memcpy(ptr, string, len); return ptr;}/** * copy_to_user_fromio - copy data from mmio-space to user-space * @dst: the destination pointer on user-space * @src: the source pointer on mmio * @count: the data size to copy in bytes * * Copies the data from mmio-space to user-space. * * Returns zero if successful, or non-zero on failure. */int copy_to_user_fromio(void __user *dst, unsigned long src, size_t count){#if defined(__i386__) || defined(CONFIG_SPARC32) return copy_to_user(dst, (const void*)src, count) ? -EFAULT : 0;#else char buf[256]; while (count) { size_t c = count; if (c > sizeof(buf)) c = sizeof(buf); memcpy_fromio(buf, (void*)src, c); if (copy_to_user(dst, buf, c)) return -EFAULT; count -= c; dst += c; src += c; } return 0;#endif}/** * copy_from_user_toio - copy data from user-space to mmio-space * @dst: the destination pointer on mmio-space * @src: the source pointer on user-space * @count: the data size to copy in bytes * * Copies the data from user-space to mmio-space. * * Returns zero if successful, or non-zero on failure. */int copy_from_user_toio(unsigned long dst, const void __user *src, size_t count){#if defined(__i386__) || defined(CONFIG_SPARC32) return copy_from_user((void*)dst, src, count) ? -EFAULT : 0;#else char buf[256]; while (count) { size_t c = count; if (c > sizeof(buf)) c = sizeof(buf); if (copy_from_user(buf, src, c)) return -EFAULT; memcpy_toio((void*)dst, buf, c); count -= c; dst += c; src += c; } return 0;#endif}
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