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-rw-r--r--drivers/char/Kconfig10
-rw-r--r--drivers/char/mem.c231
2 files changed, 0 insertions, 241 deletions
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index d229a2d0c017..b151e0fcdeb5 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -334,16 +334,6 @@ config DEVMEM
memory.
When in doubt, say "Y".
-config DEVKMEM
- bool "/dev/kmem virtual device support"
- # On arm64, VMALLOC_START < PAGE_OFFSET, which confuses kmem read/write
- depends on !ARM64
- help
- Say Y here if you want to support the /dev/kmem device. The
- /dev/kmem device is rarely used, but can be used for certain
- kind of kernel debugging operations.
- When in doubt, say "N".
-
config NVRAM
tristate "/dev/nvram support"
depends on X86 || HAVE_ARCH_NVRAM_OPS
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 869b9f5e8e03..15dc54fa1d47 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -403,221 +403,6 @@ static int mmap_mem(struct file *file, struct vm_area_struct *vma)
return 0;
}
-static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
-{
- unsigned long pfn;
-
- /* Turn a kernel-virtual address into a physical page frame */
- pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
-
- /*
- * RED-PEN: on some architectures there is more mapped memory than
- * available in mem_map which pfn_valid checks for. Perhaps should add a
- * new macro here.
- *
- * RED-PEN: vmalloc is not supported right now.
- */
- if (!pfn_valid(pfn))
- return -EIO;
-
- vma->vm_pgoff = pfn;
- return mmap_mem(file, vma);
-}
-
-/*
- * This function reads the *virtual* memory as seen by the kernel.
- */
-static ssize_t read_kmem(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- unsigned long p = *ppos;
- ssize_t low_count, read, sz;
- char *kbuf; /* k-addr because vread() takes vmlist_lock rwlock */
- int err = 0;
-
- read = 0;
- if (p < (unsigned long) high_memory) {
- low_count = count;
- if (count > (unsigned long)high_memory - p)
- low_count = (unsigned long)high_memory - p;
-
-#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
- /* we don't have page 0 mapped on sparc and m68k.. */
- if (p < PAGE_SIZE && low_count > 0) {
- sz = size_inside_page(p, low_count);
- if (clear_user(buf, sz))
- return -EFAULT;
- buf += sz;
- p += sz;
- read += sz;
- low_count -= sz;
- count -= sz;
- }
-#endif
- while (low_count > 0) {
- sz = size_inside_page(p, low_count);
-
- /*
- * On ia64 if a page has been mapped somewhere as
- * uncached, then it must also be accessed uncached
- * by the kernel or data corruption may occur
- */
- kbuf = xlate_dev_kmem_ptr((void *)p);
- if (!virt_addr_valid(kbuf))
- return -ENXIO;
-
- if (copy_to_user(buf, kbuf, sz))
- return -EFAULT;
- buf += sz;
- p += sz;
- read += sz;
- low_count -= sz;
- count -= sz;
- if (should_stop_iteration()) {
- count = 0;
- break;
- }
- }
- }
-
- if (count > 0) {
- kbuf = (char *)__get_free_page(GFP_KERNEL);
- if (!kbuf)
- return -ENOMEM;
- while (count > 0) {
- sz = size_inside_page(p, count);
- if (!is_vmalloc_or_module_addr((void *)p)) {
- err = -ENXIO;
- break;
- }
- sz = vread(kbuf, (char *)p, sz);
- if (!sz)
- break;
- if (copy_to_user(buf, kbuf, sz)) {
- err = -EFAULT;
- break;
- }
- count -= sz;
- buf += sz;
- read += sz;
- p += sz;
- if (should_stop_iteration())
- break;
- }
- free_page((unsigned long)kbuf);
- }
- *ppos = p;
- return read ? read : err;
-}
-
-
-static ssize_t do_write_kmem(unsigned long p, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- ssize_t written, sz;
- unsigned long copied;
-
- written = 0;
-#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
- /* we don't have page 0 mapped on sparc and m68k.. */
- if (p < PAGE_SIZE) {
- sz = size_inside_page(p, count);
- /* Hmm. Do something? */
- buf += sz;
- p += sz;
- count -= sz;
- written += sz;
- }
-#endif
-
- while (count > 0) {
- void *ptr;
-
- sz = size_inside_page(p, count);
-
- /*
- * On ia64 if a page has been mapped somewhere as uncached, then
- * it must also be accessed uncached by the kernel or data
- * corruption may occur.
- */
- ptr = xlate_dev_kmem_ptr((void *)p);
- if (!virt_addr_valid(ptr))
- return -ENXIO;
-
- copied = copy_from_user(ptr, buf, sz);
- if (copied) {
- written += sz - copied;
- if (written)
- break;
- return -EFAULT;
- }
- buf += sz;
- p += sz;
- count -= sz;
- written += sz;
- if (should_stop_iteration())
- break;
- }
-
- *ppos += written;
- return written;
-}
-
-/*
- * This function writes to the *virtual* memory as seen by the kernel.
- */
-static ssize_t write_kmem(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- unsigned long p = *ppos;
- ssize_t wrote = 0;
- ssize_t virtr = 0;
- char *kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
- int err = 0;
-
- if (p < (unsigned long) high_memory) {
- unsigned long to_write = min_t(unsigned long, count,
- (unsigned long)high_memory - p);
- wrote = do_write_kmem(p, buf, to_write, ppos);
- if (wrote != to_write)
- return wrote;
- p += wrote;
- buf += wrote;
- count -= wrote;
- }
-
- if (count > 0) {
- kbuf = (char *)__get_free_page(GFP_KERNEL);
- if (!kbuf)
- return wrote ? wrote : -ENOMEM;
- while (count > 0) {
- unsigned long sz = size_inside_page(p, count);
- unsigned long n;
-
- if (!is_vmalloc_or_module_addr((void *)p)) {
- err = -ENXIO;
- break;
- }
- n = copy_from_user(kbuf, buf, sz);
- if (n) {
- err = -EFAULT;
- break;
- }
- vwrite(kbuf, (char *)p, sz);
- count -= sz;
- buf += sz;
- virtr += sz;
- p += sz;
- if (should_stop_iteration())
- break;
- }
- free_page((unsigned long)kbuf);
- }
-
- *ppos = p;
- return virtr + wrote ? : err;
-}
-
static ssize_t read_port(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
@@ -855,7 +640,6 @@ static int open_port(struct inode *inode, struct file *filp)
#define write_zero write_null
#define write_iter_zero write_iter_null
#define open_mem open_port
-#define open_kmem open_mem
static const struct file_operations __maybe_unused mem_fops = {
.llseek = memory_lseek,
@@ -869,18 +653,6 @@ static const struct file_operations __maybe_unused mem_fops = {
#endif
};
-static const struct file_operations __maybe_unused kmem_fops = {
- .llseek = memory_lseek,
- .read = read_kmem,
- .write = write_kmem,
- .mmap = mmap_kmem,
- .open = open_kmem,
-#ifndef CONFIG_MMU
- .get_unmapped_area = get_unmapped_area_mem,
- .mmap_capabilities = memory_mmap_capabilities,
-#endif
-};
-
static const struct file_operations null_fops = {
.llseek = null_lseek,
.read = read_null,
@@ -925,9 +697,6 @@ static const struct memdev {
#ifdef CONFIG_DEVMEM
[DEVMEM_MINOR] = { "mem", 0, &mem_fops, FMODE_UNSIGNED_OFFSET },
#endif
-#ifdef CONFIG_DEVKMEM
- [2] = { "kmem", 0, &kmem_fops, FMODE_UNSIGNED_OFFSET },
-#endif
[3] = { "null", 0666, &null_fops, 0 },
#ifdef CONFIG_DEVPORT
[4] = { "port", 0, &port_fops, 0 },
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 03:28:16 +0000