Linux 2.6.34-rc3
[pohmelfs.git] / drivers / char / mem.c
blob1f3215ac085bca594dc014cf91e23a745a8e1058
1 /*
2 * linux/drivers/char/mem.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * Added devfs support.
7 * Jan-11-1998, C. Scott Ananian <cananian@alumni.princeton.edu>
8 * Shared /dev/zero mmapping support, Feb 2000, Kanoj Sarcar <kanoj@sgi.com>
9 */
11 #include <linux/mm.h>
12 #include <linux/miscdevice.h>
13 #include <linux/slab.h>
14 #include <linux/vmalloc.h>
15 #include <linux/mman.h>
16 #include <linux/random.h>
17 #include <linux/init.h>
18 #include <linux/raw.h>
19 #include <linux/tty.h>
20 #include <linux/capability.h>
21 #include <linux/ptrace.h>
22 #include <linux/device.h>
23 #include <linux/highmem.h>
24 #include <linux/crash_dump.h>
25 #include <linux/backing-dev.h>
26 #include <linux/bootmem.h>
27 #include <linux/splice.h>
28 #include <linux/pfn.h>
30 #include <asm/uaccess.h>
31 #include <asm/io.h>
33 #ifdef CONFIG_IA64
34 # include <linux/efi.h>
35 #endif
37 static inline unsigned long size_inside_page(unsigned long start,
38 unsigned long size)
40 unsigned long sz;
42 sz = PAGE_SIZE - (start & (PAGE_SIZE - 1));
44 return min(sz, size);
47 #ifndef ARCH_HAS_VALID_PHYS_ADDR_RANGE
48 static inline int valid_phys_addr_range(unsigned long addr, size_t count)
50 if (addr + count > __pa(high_memory))
51 return 0;
53 return 1;
56 static inline int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
58 return 1;
60 #endif
62 #ifdef CONFIG_STRICT_DEVMEM
63 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
65 u64 from = ((u64)pfn) << PAGE_SHIFT;
66 u64 to = from + size;
67 u64 cursor = from;
69 while (cursor < to) {
70 if (!devmem_is_allowed(pfn)) {
71 printk(KERN_INFO
72 "Program %s tried to access /dev/mem between %Lx->%Lx.\n",
73 current->comm, from, to);
74 return 0;
76 cursor += PAGE_SIZE;
77 pfn++;
79 return 1;
81 #else
82 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
84 return 1;
86 #endif
88 void __weak unxlate_dev_mem_ptr(unsigned long phys, void *addr)
93 * This funcion reads the *physical* memory. The f_pos points directly to the
94 * memory location.
96 static ssize_t read_mem(struct file *file, char __user *buf,
97 size_t count, loff_t *ppos)
99 unsigned long p = *ppos;
100 ssize_t read, sz;
101 char *ptr;
103 if (!valid_phys_addr_range(p, count))
104 return -EFAULT;
105 read = 0;
106 #ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
107 /* we don't have page 0 mapped on sparc and m68k.. */
108 if (p < PAGE_SIZE) {
109 sz = size_inside_page(p, count);
110 if (sz > 0) {
111 if (clear_user(buf, sz))
112 return -EFAULT;
113 buf += sz;
114 p += sz;
115 count -= sz;
116 read += sz;
119 #endif
121 while (count > 0) {
122 unsigned long remaining;
124 sz = size_inside_page(p, count);
126 if (!range_is_allowed(p >> PAGE_SHIFT, count))
127 return -EPERM;
130 * On ia64 if a page has been mapped somewhere as uncached, then
131 * it must also be accessed uncached by the kernel or data
132 * corruption may occur.
134 ptr = xlate_dev_mem_ptr(p);
135 if (!ptr)
136 return -EFAULT;
138 remaining = copy_to_user(buf, ptr, sz);
139 unxlate_dev_mem_ptr(p, ptr);
140 if (remaining)
141 return -EFAULT;
143 buf += sz;
144 p += sz;
145 count -= sz;
146 read += sz;
149 *ppos += read;
150 return read;
153 static ssize_t write_mem(struct file *file, const char __user *buf,
154 size_t count, loff_t *ppos)
156 unsigned long p = *ppos;
157 ssize_t written, sz;
158 unsigned long copied;
159 void *ptr;
161 if (!valid_phys_addr_range(p, count))
162 return -EFAULT;
164 written = 0;
166 #ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
167 /* we don't have page 0 mapped on sparc and m68k.. */
168 if (p < PAGE_SIZE) {
169 sz = size_inside_page(p, count);
170 /* Hmm. Do something? */
171 buf += sz;
172 p += sz;
173 count -= sz;
174 written += sz;
176 #endif
178 while (count > 0) {
179 sz = size_inside_page(p, count);
181 if (!range_is_allowed(p >> PAGE_SHIFT, sz))
182 return -EPERM;
185 * On ia64 if a page has been mapped somewhere as uncached, then
186 * it must also be accessed uncached by the kernel or data
187 * corruption may occur.
189 ptr = xlate_dev_mem_ptr(p);
190 if (!ptr) {
191 if (written)
192 break;
193 return -EFAULT;
196 copied = copy_from_user(ptr, buf, sz);
197 unxlate_dev_mem_ptr(p, ptr);
198 if (copied) {
199 written += sz - copied;
200 if (written)
201 break;
202 return -EFAULT;
205 buf += sz;
206 p += sz;
207 count -= sz;
208 written += sz;
211 *ppos += written;
212 return written;
215 int __weak phys_mem_access_prot_allowed(struct file *file,
216 unsigned long pfn, unsigned long size, pgprot_t *vma_prot)
218 return 1;
221 #ifndef __HAVE_PHYS_MEM_ACCESS_PROT
224 * Architectures vary in how they handle caching for addresses
225 * outside of main memory.
228 static int uncached_access(struct file *file, unsigned long addr)
230 #if defined(CONFIG_IA64)
232 * On ia64, we ignore O_DSYNC because we cannot tolerate memory
233 * attribute aliases.
235 return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
236 #elif defined(CONFIG_MIPS)
238 extern int __uncached_access(struct file *file,
239 unsigned long addr);
241 return __uncached_access(file, addr);
243 #else
245 * Accessing memory above the top the kernel knows about or through a
246 * file pointer
247 * that was marked O_DSYNC will be done non-cached.
249 if (file->f_flags & O_DSYNC)
250 return 1;
251 return addr >= __pa(high_memory);
252 #endif
255 static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
256 unsigned long size, pgprot_t vma_prot)
258 #ifdef pgprot_noncached
259 unsigned long offset = pfn << PAGE_SHIFT;
261 if (uncached_access(file, offset))
262 return pgprot_noncached(vma_prot);
263 #endif
264 return vma_prot;
266 #endif
268 #ifndef CONFIG_MMU
269 static unsigned long get_unmapped_area_mem(struct file *file,
270 unsigned long addr,
271 unsigned long len,
272 unsigned long pgoff,
273 unsigned long flags)
275 if (!valid_mmap_phys_addr_range(pgoff, len))
276 return (unsigned long) -EINVAL;
277 return pgoff << PAGE_SHIFT;
280 /* can't do an in-place private mapping if there's no MMU */
281 static inline int private_mapping_ok(struct vm_area_struct *vma)
283 return vma->vm_flags & VM_MAYSHARE;
285 #else
286 #define get_unmapped_area_mem NULL
288 static inline int private_mapping_ok(struct vm_area_struct *vma)
290 return 1;
292 #endif
294 static const struct vm_operations_struct mmap_mem_ops = {
295 #ifdef CONFIG_HAVE_IOREMAP_PROT
296 .access = generic_access_phys
297 #endif
300 static int mmap_mem(struct file *file, struct vm_area_struct *vma)
302 size_t size = vma->vm_end - vma->vm_start;
304 if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
305 return -EINVAL;
307 if (!private_mapping_ok(vma))
308 return -ENOSYS;
310 if (!range_is_allowed(vma->vm_pgoff, size))
311 return -EPERM;
313 if (!phys_mem_access_prot_allowed(file, vma->vm_pgoff, size,
314 &vma->vm_page_prot))
315 return -EINVAL;
317 vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_pgoff,
318 size,
319 vma->vm_page_prot);
321 vma->vm_ops = &mmap_mem_ops;
323 /* Remap-pfn-range will mark the range VM_IO and VM_RESERVED */
324 if (remap_pfn_range(vma,
325 vma->vm_start,
326 vma->vm_pgoff,
327 size,
328 vma->vm_page_prot)) {
329 return -EAGAIN;
331 return 0;
334 #ifdef CONFIG_DEVKMEM
335 static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
337 unsigned long pfn;
339 /* Turn a kernel-virtual address into a physical page frame */
340 pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
343 * RED-PEN: on some architectures there is more mapped memory than
344 * available in mem_map which pfn_valid checks for. Perhaps should add a
345 * new macro here.
347 * RED-PEN: vmalloc is not supported right now.
349 if (!pfn_valid(pfn))
350 return -EIO;
352 vma->vm_pgoff = pfn;
353 return mmap_mem(file, vma);
355 #endif
357 #ifdef CONFIG_CRASH_DUMP
359 * Read memory corresponding to the old kernel.
361 static ssize_t read_oldmem(struct file *file, char __user *buf,
362 size_t count, loff_t *ppos)
364 unsigned long pfn, offset;
365 size_t read = 0, csize;
366 int rc = 0;
368 while (count) {
369 pfn = *ppos / PAGE_SIZE;
370 if (pfn > saved_max_pfn)
371 return read;
373 offset = (unsigned long)(*ppos % PAGE_SIZE);
374 if (count > PAGE_SIZE - offset)
375 csize = PAGE_SIZE - offset;
376 else
377 csize = count;
379 rc = copy_oldmem_page(pfn, buf, csize, offset, 1);
380 if (rc < 0)
381 return rc;
382 buf += csize;
383 *ppos += csize;
384 read += csize;
385 count -= csize;
387 return read;
389 #endif
391 #ifdef CONFIG_DEVKMEM
393 * This function reads the *virtual* memory as seen by the kernel.
395 static ssize_t read_kmem(struct file *file, char __user *buf,
396 size_t count, loff_t *ppos)
398 unsigned long p = *ppos;
399 ssize_t low_count, read, sz;
400 char * kbuf; /* k-addr because vread() takes vmlist_lock rwlock */
401 int err = 0;
403 read = 0;
404 if (p < (unsigned long) high_memory) {
405 low_count = count;
406 if (count > (unsigned long)high_memory - p)
407 low_count = (unsigned long)high_memory - p;
409 #ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
410 /* we don't have page 0 mapped on sparc and m68k.. */
411 if (p < PAGE_SIZE && low_count > 0) {
412 sz = size_inside_page(p, low_count);
413 if (clear_user(buf, sz))
414 return -EFAULT;
415 buf += sz;
416 p += sz;
417 read += sz;
418 low_count -= sz;
419 count -= sz;
421 #endif
422 while (low_count > 0) {
423 sz = size_inside_page(p, low_count);
426 * On ia64 if a page has been mapped somewhere as
427 * uncached, then it must also be accessed uncached
428 * by the kernel or data corruption may occur
430 kbuf = xlate_dev_kmem_ptr((char *)p);
432 if (copy_to_user(buf, kbuf, sz))
433 return -EFAULT;
434 buf += sz;
435 p += sz;
436 read += sz;
437 low_count -= sz;
438 count -= sz;
442 if (count > 0) {
443 kbuf = (char *)__get_free_page(GFP_KERNEL);
444 if (!kbuf)
445 return -ENOMEM;
446 while (count > 0) {
447 sz = size_inside_page(p, count);
448 if (!is_vmalloc_or_module_addr((void *)p)) {
449 err = -ENXIO;
450 break;
452 sz = vread(kbuf, (char *)p, sz);
453 if (!sz)
454 break;
455 if (copy_to_user(buf, kbuf, sz)) {
456 err = -EFAULT;
457 break;
459 count -= sz;
460 buf += sz;
461 read += sz;
462 p += sz;
464 free_page((unsigned long)kbuf);
466 *ppos = p;
467 return read ? read : err;
471 static ssize_t do_write_kmem(unsigned long p, const char __user *buf,
472 size_t count, loff_t *ppos)
474 ssize_t written, sz;
475 unsigned long copied;
477 written = 0;
478 #ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
479 /* we don't have page 0 mapped on sparc and m68k.. */
480 if (p < PAGE_SIZE) {
481 sz = size_inside_page(p, count);
482 /* Hmm. Do something? */
483 buf += sz;
484 p += sz;
485 count -= sz;
486 written += sz;
488 #endif
490 while (count > 0) {
491 char *ptr;
493 sz = size_inside_page(p, count);
496 * On ia64 if a page has been mapped somewhere as uncached, then
497 * it must also be accessed uncached by the kernel or data
498 * corruption may occur.
500 ptr = xlate_dev_kmem_ptr((char *)p);
502 copied = copy_from_user(ptr, buf, sz);
503 if (copied) {
504 written += sz - copied;
505 if (written)
506 break;
507 return -EFAULT;
509 buf += sz;
510 p += sz;
511 count -= sz;
512 written += sz;
515 *ppos += written;
516 return written;
520 * This function writes to the *virtual* memory as seen by the kernel.
522 static ssize_t write_kmem(struct file *file, const char __user *buf,
523 size_t count, loff_t *ppos)
525 unsigned long p = *ppos;
526 ssize_t wrote = 0;
527 ssize_t virtr = 0;
528 char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
529 int err = 0;
531 if (p < (unsigned long) high_memory) {
532 unsigned long to_write = min_t(unsigned long, count,
533 (unsigned long)high_memory - p);
534 wrote = do_write_kmem(p, buf, to_write, ppos);
535 if (wrote != to_write)
536 return wrote;
537 p += wrote;
538 buf += wrote;
539 count -= wrote;
542 if (count > 0) {
543 kbuf = (char *)__get_free_page(GFP_KERNEL);
544 if (!kbuf)
545 return wrote ? wrote : -ENOMEM;
546 while (count > 0) {
547 unsigned long sz = size_inside_page(p, count);
548 unsigned long n;
550 if (!is_vmalloc_or_module_addr((void *)p)) {
551 err = -ENXIO;
552 break;
554 n = copy_from_user(kbuf, buf, sz);
555 if (n) {
556 err = -EFAULT;
557 break;
559 vwrite(kbuf, (char *)p, sz);
560 count -= sz;
561 buf += sz;
562 virtr += sz;
563 p += sz;
565 free_page((unsigned long)kbuf);
568 *ppos = p;
569 return virtr + wrote ? : err;
571 #endif
573 #ifdef CONFIG_DEVPORT
574 static ssize_t read_port(struct file *file, char __user *buf,
575 size_t count, loff_t *ppos)
577 unsigned long i = *ppos;
578 char __user *tmp = buf;
580 if (!access_ok(VERIFY_WRITE, buf, count))
581 return -EFAULT;
582 while (count-- > 0 && i < 65536) {
583 if (__put_user(inb(i), tmp) < 0)
584 return -EFAULT;
585 i++;
586 tmp++;
588 *ppos = i;
589 return tmp-buf;
592 static ssize_t write_port(struct file *file, const char __user *buf,
593 size_t count, loff_t *ppos)
595 unsigned long i = *ppos;
596 const char __user * tmp = buf;
598 if (!access_ok(VERIFY_READ, buf, count))
599 return -EFAULT;
600 while (count-- > 0 && i < 65536) {
601 char c;
602 if (__get_user(c, tmp)) {
603 if (tmp > buf)
604 break;
605 return -EFAULT;
607 outb(c, i);
608 i++;
609 tmp++;
611 *ppos = i;
612 return tmp-buf;
614 #endif
616 static ssize_t read_null(struct file *file, char __user *buf,
617 size_t count, loff_t *ppos)
619 return 0;
622 static ssize_t write_null(struct file *file, const char __user *buf,
623 size_t count, loff_t *ppos)
625 return count;
628 static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
629 struct splice_desc *sd)
631 return sd->len;
634 static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out,
635 loff_t *ppos, size_t len, unsigned int flags)
637 return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null);
640 static ssize_t read_zero(struct file *file, char __user *buf,
641 size_t count, loff_t *ppos)
643 size_t written;
645 if (!count)
646 return 0;
648 if (!access_ok(VERIFY_WRITE, buf, count))
649 return -EFAULT;
651 written = 0;
652 while (count) {
653 unsigned long unwritten;
654 size_t chunk = count;
656 if (chunk > PAGE_SIZE)
657 chunk = PAGE_SIZE; /* Just for latency reasons */
658 unwritten = __clear_user(buf, chunk);
659 written += chunk - unwritten;
660 if (unwritten)
661 break;
662 if (signal_pending(current))
663 return written ? written : -ERESTARTSYS;
664 buf += chunk;
665 count -= chunk;
666 cond_resched();
668 return written ? written : -EFAULT;
671 static int mmap_zero(struct file *file, struct vm_area_struct *vma)
673 #ifndef CONFIG_MMU
674 return -ENOSYS;
675 #endif
676 if (vma->vm_flags & VM_SHARED)
677 return shmem_zero_setup(vma);
678 return 0;
681 static ssize_t write_full(struct file *file, const char __user *buf,
682 size_t count, loff_t *ppos)
684 return -ENOSPC;
688 * Special lseek() function for /dev/null and /dev/zero. Most notably, you
689 * can fopen() both devices with "a" now. This was previously impossible.
690 * -- SRB.
692 static loff_t null_lseek(struct file *file, loff_t offset, int orig)
694 return file->f_pos = 0;
698 * The memory devices use the full 32/64 bits of the offset, and so we cannot
699 * check against negative addresses: they are ok. The return value is weird,
700 * though, in that case (0).
702 * also note that seeking relative to the "end of file" isn't supported:
703 * it has no meaning, so it returns -EINVAL.
705 static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
707 loff_t ret;
709 mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
710 switch (orig) {
711 case SEEK_CUR:
712 offset += file->f_pos;
713 if ((unsigned long long)offset <
714 (unsigned long long)file->f_pos) {
715 ret = -EOVERFLOW;
716 break;
718 case SEEK_SET:
719 /* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
720 if ((unsigned long long)offset >= ~0xFFFULL) {
721 ret = -EOVERFLOW;
722 break;
724 file->f_pos = offset;
725 ret = file->f_pos;
726 force_successful_syscall_return();
727 break;
728 default:
729 ret = -EINVAL;
731 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
732 return ret;
735 static int open_port(struct inode * inode, struct file * filp)
737 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
740 #define zero_lseek null_lseek
741 #define full_lseek null_lseek
742 #define write_zero write_null
743 #define read_full read_zero
744 #define open_mem open_port
745 #define open_kmem open_mem
746 #define open_oldmem open_mem
748 static const struct file_operations mem_fops = {
749 .llseek = memory_lseek,
750 .read = read_mem,
751 .write = write_mem,
752 .mmap = mmap_mem,
753 .open = open_mem,
754 .get_unmapped_area = get_unmapped_area_mem,
757 #ifdef CONFIG_DEVKMEM
758 static const struct file_operations kmem_fops = {
759 .llseek = memory_lseek,
760 .read = read_kmem,
761 .write = write_kmem,
762 .mmap = mmap_kmem,
763 .open = open_kmem,
764 .get_unmapped_area = get_unmapped_area_mem,
766 #endif
768 static const struct file_operations null_fops = {
769 .llseek = null_lseek,
770 .read = read_null,
771 .write = write_null,
772 .splice_write = splice_write_null,
775 #ifdef CONFIG_DEVPORT
776 static const struct file_operations port_fops = {
777 .llseek = memory_lseek,
778 .read = read_port,
779 .write = write_port,
780 .open = open_port,
782 #endif
784 static const struct file_operations zero_fops = {
785 .llseek = zero_lseek,
786 .read = read_zero,
787 .write = write_zero,
788 .mmap = mmap_zero,
792 * capabilities for /dev/zero
793 * - permits private mappings, "copies" are taken of the source of zeros
795 static struct backing_dev_info zero_bdi = {
796 .name = "char/mem",
797 .capabilities = BDI_CAP_MAP_COPY,
800 static const struct file_operations full_fops = {
801 .llseek = full_lseek,
802 .read = read_full,
803 .write = write_full,
806 #ifdef CONFIG_CRASH_DUMP
807 static const struct file_operations oldmem_fops = {
808 .read = read_oldmem,
809 .open = open_oldmem,
811 #endif
813 static ssize_t kmsg_write(struct file *file, const char __user *buf,
814 size_t count, loff_t *ppos)
816 char *tmp;
817 ssize_t ret;
819 tmp = kmalloc(count + 1, GFP_KERNEL);
820 if (tmp == NULL)
821 return -ENOMEM;
822 ret = -EFAULT;
823 if (!copy_from_user(tmp, buf, count)) {
824 tmp[count] = 0;
825 ret = printk("%s", tmp);
826 if (ret > count)
827 /* printk can add a prefix */
828 ret = count;
830 kfree(tmp);
831 return ret;
834 static const struct file_operations kmsg_fops = {
835 .write = kmsg_write,
838 static const struct memdev {
839 const char *name;
840 mode_t mode;
841 const struct file_operations *fops;
842 struct backing_dev_info *dev_info;
843 } devlist[] = {
844 [1] = { "mem", 0, &mem_fops, &directly_mappable_cdev_bdi },
845 #ifdef CONFIG_DEVKMEM
846 [2] = { "kmem", 0, &kmem_fops, &directly_mappable_cdev_bdi },
847 #endif
848 [3] = { "null", 0666, &null_fops, NULL },
849 #ifdef CONFIG_DEVPORT
850 [4] = { "port", 0, &port_fops, NULL },
851 #endif
852 [5] = { "zero", 0666, &zero_fops, &zero_bdi },
853 [7] = { "full", 0666, &full_fops, NULL },
854 [8] = { "random", 0666, &random_fops, NULL },
855 [9] = { "urandom", 0666, &urandom_fops, NULL },
856 [11] = { "kmsg", 0, &kmsg_fops, NULL },
857 #ifdef CONFIG_CRASH_DUMP
858 [12] = { "oldmem", 0, &oldmem_fops, NULL },
859 #endif
862 static int memory_open(struct inode *inode, struct file *filp)
864 int minor;
865 const struct memdev *dev;
867 minor = iminor(inode);
868 if (minor >= ARRAY_SIZE(devlist))
869 return -ENXIO;
871 dev = &devlist[minor];
872 if (!dev->fops)
873 return -ENXIO;
875 filp->f_op = dev->fops;
876 if (dev->dev_info)
877 filp->f_mapping->backing_dev_info = dev->dev_info;
879 if (dev->fops->open)
880 return dev->fops->open(inode, filp);
882 return 0;
885 static const struct file_operations memory_fops = {
886 .open = memory_open,
889 static char *mem_devnode(struct device *dev, mode_t *mode)
891 if (mode && devlist[MINOR(dev->devt)].mode)
892 *mode = devlist[MINOR(dev->devt)].mode;
893 return NULL;
896 static struct class *mem_class;
898 static int __init chr_dev_init(void)
900 int minor;
901 int err;
903 err = bdi_init(&zero_bdi);
904 if (err)
905 return err;
907 if (register_chrdev(MEM_MAJOR, "mem", &memory_fops))
908 printk("unable to get major %d for memory devs\n", MEM_MAJOR);
910 mem_class = class_create(THIS_MODULE, "mem");
911 mem_class->devnode = mem_devnode;
912 for (minor = 1; minor < ARRAY_SIZE(devlist); minor++) {
913 if (!devlist[minor].name)
914 continue;
915 device_create(mem_class, NULL, MKDEV(MEM_MAJOR, minor),
916 NULL, devlist[minor].name);
919 return 0;
922 fs_initcall(chr_dev_init);