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-rw-r--r--drivers/char/mem.c204
1 files changed, 102 insertions, 102 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index e3f5577cbce3..1f3215ac085b 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -3,7 +3,7 @@
3 * 3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds 4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * 5 *
6 * Added devfs support. 6 * Added devfs support.
7 * Jan-11-1998, C. Scott Ananian <cananian@alumni.princeton.edu> 7 * Jan-11-1998, C. Scott Ananian <cananian@alumni.princeton.edu>
8 * Shared /dev/zero mmapping support, Feb 2000, Kanoj Sarcar <kanoj@sgi.com> 8 * Shared /dev/zero mmapping support, Feb 2000, Kanoj Sarcar <kanoj@sgi.com>
9 */ 9 */
@@ -44,36 +44,6 @@ static inline unsigned long size_inside_page(unsigned long start,
44 return min(sz, size); 44 return min(sz, size);
45} 45}
46 46
47/*
48 * Architectures vary in how they handle caching for addresses
49 * outside of main memory.
50 *
51 */
52static inline int uncached_access(struct file *file, unsigned long addr)
53{
54#if defined(CONFIG_IA64)
55 /*
56 * On ia64, we ignore O_DSYNC because we cannot tolerate memory attribute aliases.
57 */
58 return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
59#elif defined(CONFIG_MIPS)
60 {
61 extern int __uncached_access(struct file *file,
62 unsigned long addr);
63
64 return __uncached_access(file, addr);
65 }
66#else
67 /*
68 * Accessing memory above the top the kernel knows about or through a file pointer
69 * that was marked O_DSYNC will be done non-cached.
70 */
71 if (file->f_flags & O_DSYNC)
72 return 1;
73 return addr >= __pa(high_memory);
74#endif
75}
76
77#ifndef ARCH_HAS_VALID_PHYS_ADDR_RANGE 47#ifndef ARCH_HAS_VALID_PHYS_ADDR_RANGE
78static inline int valid_phys_addr_range(unsigned long addr, size_t count) 48static inline int valid_phys_addr_range(unsigned long addr, size_t count)
79{ 49{
@@ -115,15 +85,15 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
115} 85}
116#endif 86#endif
117 87
118void __attribute__((weak)) unxlate_dev_mem_ptr(unsigned long phys, void *addr) 88void __weak unxlate_dev_mem_ptr(unsigned long phys, void *addr)
119{ 89{
120} 90}
121 91
122/* 92/*
123 * This funcion reads the *physical* memory. The f_pos points directly to the 93 * This funcion reads the *physical* memory. The f_pos points directly to the
124 * memory location. 94 * memory location.
125 */ 95 */
126static ssize_t read_mem(struct file * file, char __user * buf, 96static ssize_t read_mem(struct file *file, char __user *buf,
127 size_t count, loff_t *ppos) 97 size_t count, loff_t *ppos)
128{ 98{
129 unsigned long p = *ppos; 99 unsigned long p = *ppos;
@@ -140,10 +110,10 @@ static ssize_t read_mem(struct file * file, char __user * buf,
140 if (sz > 0) { 110 if (sz > 0) {
141 if (clear_user(buf, sz)) 111 if (clear_user(buf, sz))
142 return -EFAULT; 112 return -EFAULT;
143 buf += sz; 113 buf += sz;
144 p += sz; 114 p += sz;
145 count -= sz; 115 count -= sz;
146 read += sz; 116 read += sz;
147 } 117 }
148 } 118 }
149#endif 119#endif
@@ -157,9 +127,9 @@ static ssize_t read_mem(struct file * file, char __user * buf,
157 return -EPERM; 127 return -EPERM;
158 128
159 /* 129 /*
160 * On ia64 if a page has been mapped somewhere as 130 * On ia64 if a page has been mapped somewhere as uncached, then
161 * uncached, then it must also be accessed uncached 131 * it must also be accessed uncached by the kernel or data
162 * by the kernel or data corruption may occur 132 * corruption may occur.
163 */ 133 */
164 ptr = xlate_dev_mem_ptr(p); 134 ptr = xlate_dev_mem_ptr(p);
165 if (!ptr) 135 if (!ptr)
@@ -180,7 +150,7 @@ static ssize_t read_mem(struct file * file, char __user * buf,
180 return read; 150 return read;
181} 151}
182 152
183static ssize_t write_mem(struct file * file, const char __user * buf, 153static ssize_t write_mem(struct file *file, const char __user *buf,
184 size_t count, loff_t *ppos) 154 size_t count, loff_t *ppos)
185{ 155{
186 unsigned long p = *ppos; 156 unsigned long p = *ppos;
@@ -212,9 +182,9 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
212 return -EPERM; 182 return -EPERM;
213 183
214 /* 184 /*
215 * On ia64 if a page has been mapped somewhere as 185 * On ia64 if a page has been mapped somewhere as uncached, then
216 * uncached, then it must also be accessed uncached 186 * it must also be accessed uncached by the kernel or data
217 * by the kernel or data corruption may occur 187 * corruption may occur.
218 */ 188 */
219 ptr = xlate_dev_mem_ptr(p); 189 ptr = xlate_dev_mem_ptr(p);
220 if (!ptr) { 190 if (!ptr) {
@@ -242,13 +212,46 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
242 return written; 212 return written;
243} 213}
244 214
245int __attribute__((weak)) phys_mem_access_prot_allowed(struct file *file, 215int __weak phys_mem_access_prot_allowed(struct file *file,
246 unsigned long pfn, unsigned long size, pgprot_t *vma_prot) 216 unsigned long pfn, unsigned long size, pgprot_t *vma_prot)
247{ 217{
248 return 1; 218 return 1;
249} 219}
250 220
251#ifndef __HAVE_PHYS_MEM_ACCESS_PROT 221#ifndef __HAVE_PHYS_MEM_ACCESS_PROT
222
223/*
224 * Architectures vary in how they handle caching for addresses
225 * outside of main memory.
226 *
227 */
228static int uncached_access(struct file *file, unsigned long addr)
229{
230#if defined(CONFIG_IA64)
231 /*
232 * On ia64, we ignore O_DSYNC because we cannot tolerate memory
233 * attribute aliases.
234 */
235 return !(efi_mem_attributes(addr) & EFI_MEMORY_WB);
236#elif defined(CONFIG_MIPS)
237 {
238 extern int __uncached_access(struct file *file,
239 unsigned long addr);
240
241 return __uncached_access(file, addr);
242 }
243#else
244 /*
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.
248 */
249 if (file->f_flags & O_DSYNC)
250 return 1;
251 return addr >= __pa(high_memory);
252#endif
253}
254
252static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 255static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
253 unsigned long size, pgprot_t vma_prot) 256 unsigned long size, pgprot_t vma_prot)
254{ 257{
@@ -294,7 +297,7 @@ static const struct vm_operations_struct mmap_mem_ops = {
294#endif 297#endif
295}; 298};
296 299
297static int mmap_mem(struct file * file, struct vm_area_struct * vma) 300static int mmap_mem(struct file *file, struct vm_area_struct *vma)
298{ 301{
299 size_t size = vma->vm_end - vma->vm_start; 302 size_t size = vma->vm_end - vma->vm_start;
300 303
@@ -329,7 +332,7 @@ static int mmap_mem(struct file * file, struct vm_area_struct * vma)
329} 332}
330 333
331#ifdef CONFIG_DEVKMEM 334#ifdef CONFIG_DEVKMEM
332static int mmap_kmem(struct file * file, struct vm_area_struct * vma) 335static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
333{ 336{
334 unsigned long pfn; 337 unsigned long pfn;
335 338
@@ -337,9 +340,9 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
337 pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT; 340 pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
338 341
339 /* 342 /*
340 * RED-PEN: on some architectures there is more mapped memory 343 * RED-PEN: on some architectures there is more mapped memory than
341 * than available in mem_map which pfn_valid checks 344 * available in mem_map which pfn_valid checks for. Perhaps should add a
342 * for. Perhaps should add a new macro here. 345 * new macro here.
343 * 346 *
344 * RED-PEN: vmalloc is not supported right now. 347 * RED-PEN: vmalloc is not supported right now.
345 */ 348 */
@@ -389,7 +392,7 @@ static ssize_t read_oldmem(struct file *file, char __user *buf,
389/* 392/*
390 * This function reads the *virtual* memory as seen by the kernel. 393 * This function reads the *virtual* memory as seen by the kernel.
391 */ 394 */
392static ssize_t read_kmem(struct file *file, char __user *buf, 395static ssize_t read_kmem(struct file *file, char __user *buf,
393 size_t count, loff_t *ppos) 396 size_t count, loff_t *ppos)
394{ 397{
395 unsigned long p = *ppos; 398 unsigned long p = *ppos;
@@ -400,8 +403,8 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
400 read = 0; 403 read = 0;
401 if (p < (unsigned long) high_memory) { 404 if (p < (unsigned long) high_memory) {
402 low_count = count; 405 low_count = count;
403 if (count > (unsigned long) high_memory - p) 406 if (count > (unsigned long)high_memory - p)
404 low_count = (unsigned long) high_memory - p; 407 low_count = (unsigned long)high_memory - p;
405 408
406#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED 409#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
407 /* we don't have page 0 mapped on sparc and m68k.. */ 410 /* we don't have page 0 mapped on sparc and m68k.. */
@@ -465,9 +468,8 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
465} 468}
466 469
467 470
468static inline ssize_t 471static ssize_t do_write_kmem(unsigned long p, const char __user *buf,
469do_write_kmem(unsigned long p, const char __user *buf, 472 size_t count, loff_t *ppos)
470 size_t count, loff_t *ppos)
471{ 473{
472 ssize_t written, sz; 474 ssize_t written, sz;
473 unsigned long copied; 475 unsigned long copied;
@@ -491,9 +493,9 @@ do_write_kmem(unsigned long p, const char __user *buf,
491 sz = size_inside_page(p, count); 493 sz = size_inside_page(p, count);
492 494
493 /* 495 /*
494 * On ia64 if a page has been mapped somewhere as 496 * On ia64 if a page has been mapped somewhere as uncached, then
495 * uncached, then it must also be accessed uncached 497 * it must also be accessed uncached by the kernel or data
496 * by the kernel or data corruption may occur 498 * corruption may occur.
497 */ 499 */
498 ptr = xlate_dev_kmem_ptr((char *)p); 500 ptr = xlate_dev_kmem_ptr((char *)p);
499 501
@@ -514,11 +516,10 @@ do_write_kmem(unsigned long p, const char __user *buf,
514 return written; 516 return written;
515} 517}
516 518
517
518/* 519/*
519 * This function writes to the *virtual* memory as seen by the kernel. 520 * This function writes to the *virtual* memory as seen by the kernel.
520 */ 521 */
521static ssize_t write_kmem(struct file * file, const char __user * buf, 522static ssize_t write_kmem(struct file *file, const char __user *buf,
522 size_t count, loff_t *ppos) 523 size_t count, loff_t *ppos)
523{ 524{
524 unsigned long p = *ppos; 525 unsigned long p = *ppos;
@@ -570,17 +571,17 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
570#endif 571#endif
571 572
572#ifdef CONFIG_DEVPORT 573#ifdef CONFIG_DEVPORT
573static ssize_t read_port(struct file * file, char __user * buf, 574static ssize_t read_port(struct file *file, char __user *buf,
574 size_t count, loff_t *ppos) 575 size_t count, loff_t *ppos)
575{ 576{
576 unsigned long i = *ppos; 577 unsigned long i = *ppos;
577 char __user *tmp = buf; 578 char __user *tmp = buf;
578 579
579 if (!access_ok(VERIFY_WRITE, buf, count)) 580 if (!access_ok(VERIFY_WRITE, buf, count))
580 return -EFAULT; 581 return -EFAULT;
581 while (count-- > 0 && i < 65536) { 582 while (count-- > 0 && i < 65536) {
582 if (__put_user(inb(i),tmp) < 0) 583 if (__put_user(inb(i), tmp) < 0)
583 return -EFAULT; 584 return -EFAULT;
584 i++; 585 i++;
585 tmp++; 586 tmp++;
586 } 587 }
@@ -588,22 +589,22 @@ static ssize_t read_port(struct file * file, char __user * buf,
588 return tmp-buf; 589 return tmp-buf;
589} 590}
590 591
591static ssize_t write_port(struct file * file, const char __user * buf, 592static ssize_t write_port(struct file *file, const char __user *buf,
592 size_t count, loff_t *ppos) 593 size_t count, loff_t *ppos)
593{ 594{
594 unsigned long i = *ppos; 595 unsigned long i = *ppos;
595 const char __user * tmp = buf; 596 const char __user * tmp = buf;
596 597
597 if (!access_ok(VERIFY_READ,buf,count)) 598 if (!access_ok(VERIFY_READ, buf, count))
598 return -EFAULT; 599 return -EFAULT;
599 while (count-- > 0 && i < 65536) { 600 while (count-- > 0 && i < 65536) {
600 char c; 601 char c;
601 if (__get_user(c, tmp)) { 602 if (__get_user(c, tmp)) {
602 if (tmp > buf) 603 if (tmp > buf)
603 break; 604 break;
604 return -EFAULT; 605 return -EFAULT;
605 } 606 }
606 outb(c,i); 607 outb(c, i);
607 i++; 608 i++;
608 tmp++; 609 tmp++;
609 } 610 }
@@ -612,13 +613,13 @@ static ssize_t write_port(struct file * file, const char __user * buf,
612} 613}
613#endif 614#endif
614 615
615static ssize_t read_null(struct file * file, char __user * buf, 616static ssize_t read_null(struct file *file, char __user *buf,
616 size_t count, loff_t *ppos) 617 size_t count, loff_t *ppos)
617{ 618{
618 return 0; 619 return 0;
619} 620}
620 621
621static ssize_t write_null(struct file * file, const char __user * buf, 622static ssize_t write_null(struct file *file, const char __user *buf,
622 size_t count, loff_t *ppos) 623 size_t count, loff_t *ppos)
623{ 624{
624 return count; 625 return count;
@@ -630,13 +631,13 @@ static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
630 return sd->len; 631 return sd->len;
631} 632}
632 633
633static ssize_t splice_write_null(struct pipe_inode_info *pipe,struct file *out, 634static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out,
634 loff_t *ppos, size_t len, unsigned int flags) 635 loff_t *ppos, size_t len, unsigned int flags)
635{ 636{
636 return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null); 637 return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null);
637} 638}
638 639
639static ssize_t read_zero(struct file * file, char __user * buf, 640static ssize_t read_zero(struct file *file, char __user *buf,
640 size_t count, loff_t *ppos) 641 size_t count, loff_t *ppos)
641{ 642{
642 size_t written; 643 size_t written;
@@ -667,7 +668,7 @@ static ssize_t read_zero(struct file * file, char __user * buf,
667 return written ? written : -EFAULT; 668 return written ? written : -EFAULT;
668} 669}
669 670
670static int mmap_zero(struct file * file, struct vm_area_struct * vma) 671static int mmap_zero(struct file *file, struct vm_area_struct *vma)
671{ 672{
672#ifndef CONFIG_MMU 673#ifndef CONFIG_MMU
673 return -ENOSYS; 674 return -ENOSYS;
@@ -677,7 +678,7 @@ static int mmap_zero(struct file * file, struct vm_area_struct * vma)
677 return 0; 678 return 0;
678} 679}
679 680
680static ssize_t write_full(struct file * file, const char __user * buf, 681static ssize_t write_full(struct file *file, const char __user *buf,
681 size_t count, loff_t *ppos) 682 size_t count, loff_t *ppos)
682{ 683{
683 return -ENOSPC; 684 return -ENOSPC;
@@ -688,8 +689,7 @@ static ssize_t write_full(struct file * file, const char __user * buf,
688 * can fopen() both devices with "a" now. This was previously impossible. 689 * can fopen() both devices with "a" now. This was previously impossible.
689 * -- SRB. 690 * -- SRB.
690 */ 691 */
691 692static loff_t null_lseek(struct file *file, loff_t offset, int orig)
692static loff_t null_lseek(struct file * file, loff_t offset, int orig)
693{ 693{
694 return file->f_pos = 0; 694 return file->f_pos = 0;
695} 695}
@@ -702,31 +702,31 @@ static loff_t null_lseek(struct file * file, loff_t offset, int orig)
702 * also note that seeking relative to the "end of file" isn't supported: 702 * also note that seeking relative to the "end of file" isn't supported:
703 * it has no meaning, so it returns -EINVAL. 703 * it has no meaning, so it returns -EINVAL.
704 */ 704 */
705static loff_t memory_lseek(struct file * file, loff_t offset, int orig) 705static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
706{ 706{
707 loff_t ret; 707 loff_t ret;
708 708
709 mutex_lock(&file->f_path.dentry->d_inode->i_mutex); 709 mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
710 switch (orig) { 710 switch (orig) {
711 case SEEK_CUR: 711 case SEEK_CUR:
712 offset += file->f_pos; 712 offset += file->f_pos;
713 if ((unsigned long long)offset < 713 if ((unsigned long long)offset <
714 (unsigned long long)file->f_pos) { 714 (unsigned long long)file->f_pos) {
715 ret = -EOVERFLOW; 715 ret = -EOVERFLOW;
716 break; 716 break;
717 } 717 }
718 case SEEK_SET: 718 case SEEK_SET:
719 /* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */ 719 /* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
720 if ((unsigned long long)offset >= ~0xFFFULL) { 720 if ((unsigned long long)offset >= ~0xFFFULL) {
721 ret = -EOVERFLOW; 721 ret = -EOVERFLOW;
722 break;
723 }
724 file->f_pos = offset;
725 ret = file->f_pos;
726 force_successful_syscall_return();
727 break; 722 break;
728 default: 723 }
729 ret = -EINVAL; 724 file->f_pos = offset;
725 ret = file->f_pos;
726 force_successful_syscall_return();
727 break;
728 default:
729 ret = -EINVAL;
730 } 730 }
731 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); 731 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
732 return ret; 732 return ret;
@@ -810,7 +810,7 @@ static const struct file_operations oldmem_fops = {
810}; 810};
811#endif 811#endif
812 812
813static ssize_t kmsg_write(struct file * file, const char __user * buf, 813static ssize_t kmsg_write(struct file *file, const char __user *buf,
814 size_t count, loff_t *ppos) 814 size_t count, loff_t *ppos)
815{ 815{
816 char *tmp; 816 char *tmp;
@@ -832,7 +832,7 @@ static ssize_t kmsg_write(struct file * file, const char __user * buf,
832} 832}
833 833
834static const struct file_operations kmsg_fops = { 834static const struct file_operations kmsg_fops = {
835 .write = kmsg_write, 835 .write = kmsg_write,
836}; 836};
837 837
838static const struct memdev { 838static const struct memdev {
@@ -883,7 +883,7 @@ static int memory_open(struct inode *inode, struct file *filp)
883} 883}
884 884
885static const struct file_operations memory_fops = { 885static const struct file_operations memory_fops = {
886 .open = memory_open, 886 .open = memory_open,
887}; 887};
888 888
889static char *mem_devnode(struct device *dev, mode_t *mode) 889static char *mem_devnode(struct device *dev, mode_t *mode)
@@ -904,7 +904,7 @@ static int __init chr_dev_init(void)
904 if (err) 904 if (err)
905 return err; 905 return err;
906 906
907 if (register_chrdev(MEM_MAJOR,"mem",&memory_fops)) 907 if (register_chrdev(MEM_MAJOR, "mem", &memory_fops))
908 printk("unable to get major %d for memory devs\n", MEM_MAJOR); 908 printk("unable to get major %d for memory devs\n", MEM_MAJOR);
909 909
910 mem_class = class_create(THIS_MODULE, "mem"); 910 mem_class = class_create(THIS_MODULE, "mem");