bitmap: Fix mistakes in comments.

[pintos-anon] / src / lib / kernel / bitmap.c

diff --git a/src/lib/kernel/bitmap.c b/src/lib/kernel/bitmap.c
index df23cc34c1b8c9dddf86d8cc3796904838e36dac..d14a98cf343e935a390d9fd5702980ea50640dc6 100644 (file)
--- a/src/lib/kernel/bitmap.c
+++ b/src/lib/kernel/bitmap.c
@@ -71,10 +71,10 @@ last_mask (const struct bitmap *b)
 \f
 /* Creation and destruction. */
 
-/* Initializes B to be a bitmap of BIT_CNT bits
-   and sets all of its bits to false.
-   Returns true if success, false if memory allocation
-   failed. */
+/* Creates and returns a pointer to a newly allocated bitmap with room for
+   BIT_CNT (or more) bits.  Returns a null pointer if memory allocation fails.
+   The caller is responsible for freeing the bitmap, with bitmap_destroy(),
+   when it is no longer needed. */
 struct bitmap *
 bitmap_create (size_t bit_cnt) 
 {
@@ -118,8 +118,7 @@ bitmap_buf_size (size_t bit_cnt)
 }
 
 /* Destroys bitmap B, freeing its storage.
-   Not for use on bitmaps created by
-   bitmap_create_preallocated(). */
+   Not for use on bitmaps created by bitmap_create_in_buf(). */
 void
 bitmap_destroy (struct bitmap *b) 
 {
@@ -163,7 +162,7 @@ bitmap_mark (struct bitmap *b, size_t bit_idx)
   /* This is equivalent to `b->bits[idx] |= mask' except that it
      is guaranteed to be atomic on a uniprocessor machine.  See
      the description of the OR instruction in [IA32-v2b]. */
-  asm ("or %0, %1" : "=m" (b->bits[idx]) : "r" (mask) : "cc");
+  asm ("orl %1, %0" : "=m" (b->bits[idx]) : "r" (mask) : "cc");
 }
 
 /* Atomically sets the bit numbered BIT_IDX in B to false. */
@@ -176,7 +175,7 @@ bitmap_reset (struct bitmap *b, size_t bit_idx)
   /* This is equivalent to `b->bits[idx] &= ~mask' except that it
      is guaranteed to be atomic on a uniprocessor machine.  See
      the description of the AND instruction in [IA32-v2a]. */
-  asm ("and %0, %1" : "=m" (b->bits[idx]) : "r" (~mask) : "cc");
+  asm ("andl %1, %0" : "=m" (b->bits[idx]) : "r" (~mask) : "cc");
 }
 
 /* Atomically toggles the bit numbered IDX in B;
@@ -191,7 +190,7 @@ bitmap_flip (struct bitmap *b, size_t bit_idx)
   /* This is equivalent to `b->bits[idx] ^= mask' except that it
      is guaranteed to be atomic on a uniprocessor machine.  See
      the description of the XOR instruction in [IA32-v2b]. */
-  asm ("xor %0, %1" : "=m" (b->bits[idx]) : "r" (mask) : "cc");
+  asm ("xorl %1, %0" : "=m" (b->bits[idx]) : "r" (mask) : "cc");
 }
 
 /* Returns the value of the bit numbered IDX in B. */