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Diffstat (limited to 'sound/pci/emu10k1/memory.c')
-rw-r--r--sound/pci/emu10k1/memory.c55
1 files changed, 46 insertions, 9 deletions
diff --git a/sound/pci/emu10k1/memory.c b/sound/pci/emu10k1/memory.c
index 20b0711757..d297117771 100644
--- a/sound/pci/emu10k1/memory.c
+++ b/sound/pci/emu10k1/memory.c
@@ -565,15 +565,18 @@ static inline void *offset_ptr(struct snd_emu10k1 *emu, int page, int offset)
}
/*
- * bzero(blk + offset, size)
+ * memset(blk + offset, value, size)
*/
-int snd_emu10k1_synth_bzero(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
- int offset, int size)
+int snd_emu10k1_synth_memset(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
+ int offset, int size, u8 value)
{
int page, nextofs, end_offset, temp, temp1;
void *ptr;
struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
+ if (snd_BUG_ON(offset + size > p->mem.size))
+ return -EFAULT;
+
offset += blk->offset & (PAGE_SIZE - 1);
end_offset = offset + size;
page = get_aligned_page(offset);
@@ -585,25 +588,55 @@ int snd_emu10k1_synth_bzero(struct snd_emu10k1 *emu, struct snd_util_memblk *blk
temp = temp1;
ptr = offset_ptr(emu, page + p->first_page, offset);
if (ptr)
- memset(ptr, 0, temp);
+ memset(ptr, value, temp);
offset = nextofs;
page++;
} while (offset < end_offset);
return 0;
}
-EXPORT_SYMBOL(snd_emu10k1_synth_bzero);
+EXPORT_SYMBOL(snd_emu10k1_synth_memset);
+
+// Note that the value is assumed to be suitably repetitive.
+static void xor_range(void *ptr, int size, u32 value)
+{
+ if ((long)ptr & 1) {
+ *(u8 *)ptr ^= (u8)value;
+ ptr++;
+ size--;
+ }
+ if (size > 1 && ((long)ptr & 2)) {
+ *(u16 *)ptr ^= (u16)value;
+ ptr += 2;
+ size -= 2;
+ }
+ while (size > 3) {
+ *(u32 *)ptr ^= value;
+ ptr += 4;
+ size -= 4;
+ }
+ if (size > 1) {
+ *(u16 *)ptr ^= (u16)value;
+ ptr += 2;
+ size -= 2;
+ }
+ if (size > 0)
+ *(u8 *)ptr ^= (u8)value;
+}
/*
- * copy_from_user(blk + offset, data, size)
+ * copy_from_user(blk + offset, data, size) ^ xor
*/
int snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
- int offset, const char __user *data, int size)
+ int offset, const char __user *data, int size, u32 xor)
{
int page, nextofs, end_offset, temp, temp1;
void *ptr;
struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
+ if (snd_BUG_ON(offset + size > p->mem.size))
+ return -EFAULT;
+
offset += blk->offset & (PAGE_SIZE - 1);
end_offset = offset + size;
page = get_aligned_page(offset);
@@ -614,8 +647,12 @@ int snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 *emu, struct snd_util_me
if (temp1 < temp)
temp = temp1;
ptr = offset_ptr(emu, page + p->first_page, offset);
- if (ptr && copy_from_user(ptr, data, temp))
- return -EFAULT;
+ if (ptr) {
+ if (copy_from_user(ptr, data, temp))
+ return -EFAULT;
+ if (xor)
+ xor_range(ptr, temp, xor);
+ }
offset = nextofs;
data += temp;
page++;