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/dev/mem: make size_inside_page() logic straight
Also convert more size_inside_page() users. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Avi Kivity <avi@qumranet.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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1 changed files with 12 additions and 22 deletions
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@ -39,12 +39,9 @@ static inline unsigned long size_inside_page(unsigned long start,
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{
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unsigned long sz;
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if (-start & (PAGE_SIZE - 1))
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sz = -start & (PAGE_SIZE - 1);
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else
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sz = PAGE_SIZE;
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sz = PAGE_SIZE - (start & (PAGE_SIZE - 1));
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return min_t(unsigned long, sz, size);
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return min(sz, size);
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}
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/*
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@ -139,9 +136,7 @@ static ssize_t read_mem(struct file * file, char __user * buf,
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#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
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/* we don't have page 0 mapped on sparc and m68k.. */
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if (p < PAGE_SIZE) {
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sz = PAGE_SIZE - p;
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if (sz > count)
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sz = count;
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sz = size_inside_page(p, count);
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if (sz > 0) {
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if (clear_user(buf, sz))
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return -EFAULT;
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@ -201,9 +196,7 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
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#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
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/* we don't have page 0 mapped on sparc and m68k.. */
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if (p < PAGE_SIZE) {
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unsigned long sz = PAGE_SIZE - p;
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if (sz > count)
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sz = count;
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sz = size_inside_page(p, count);
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/* Hmm. Do something? */
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buf += sz;
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p += sz;
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@ -412,15 +405,14 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
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#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
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/* we don't have page 0 mapped on sparc and m68k.. */
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if (p < PAGE_SIZE && low_count > 0) {
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size_t tmp = PAGE_SIZE - p;
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if (tmp > low_count) tmp = low_count;
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if (clear_user(buf, tmp))
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sz = size_inside_page(p, low_count);
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if (clear_user(buf, sz))
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return -EFAULT;
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buf += tmp;
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p += tmp;
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read += tmp;
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low_count -= tmp;
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count -= tmp;
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buf += sz;
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p += sz;
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read += sz;
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low_count -= sz;
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count -= sz;
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}
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#endif
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while (low_count > 0) {
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@ -480,9 +472,7 @@ do_write_kmem(void *p, unsigned long realp, const char __user * buf,
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#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
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/* we don't have page 0 mapped on sparc and m68k.. */
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if (realp < PAGE_SIZE) {
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unsigned long sz = PAGE_SIZE - realp;
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if (sz > count)
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sz = count;
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sz = size_inside_page(realp, count);
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/* Hmm. Do something? */
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buf += sz;
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p += sz;
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