]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/ppc/movc.s
xnu-792.12.6.tar.gz
[apple/xnu.git] / osfmk / ppc / movc.s
index 6dee8f87a92038b65c8f502516cbcc078b86a4f8..8284ff7bdf9db03c41af9a84f0ac1eeba78922d4 100644 (file)
@@ -1,26 +1,31 @@
 /*
  * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
  * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
- * 
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
+ * This file contains Original Code and/or Modifications of Original Code 
+ * as defined in and that are subject to the Apple Public Source License 
+ * Version 2.0 (the 'License'). You may not use this file except in 
+ * compliance with the License.  The rights granted to you under the 
+ * License may not be used to create, or enable the creation or 
+ * redistribution of, unlawful or unlicensed copies of an Apple operating 
+ * system, or to circumvent, violate, or enable the circumvention or 
+ * violation of, any terms of an Apple operating system software license 
+ * agreement.
+ *
+ * Please obtain a copy of the License at 
+ * http://www.opensource.apple.com/apsl/ and read it before using this 
  * file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
+ *
+ * The Original Code and all software distributed under the License are 
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
+ * Please see the License for the specific language governing rights and 
  * limitations under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
@@ -464,7 +469,7 @@ pmap_novmx_icache_flush:
 // Stack frame format used by copyin, copyout, copyinstr and copyoutstr.
 // These routines all run both on 32 and 64-bit machines, though because they are called
 // by the BSD kernel they are always in 32-bit mode when entered.  The mapped ptr returned
-// by MapUserAddressSpace will be 64 bits however on 64-bit machines.  Beware to avoid
+// by MapUserMemoryWindow will be 64 bits however on 64-bit machines.  Beware to avoid
 // using compare instructions on this ptr.  This mapped ptr is kept globally in r31, so there
 // is no need to store or load it, which are mode-dependent operations since it could be
 // 32 or 64 bits.
@@ -472,11 +477,12 @@ pmap_novmx_icache_flush:
 #define        kkFrameSize     (FM_SIZE+32)
 
 #define        kkBufSize       (FM_SIZE+0)
-#define        kkCR            (FM_SIZE+4)
+#define        kkCR3           (FM_SIZE+4)
 #define        kkSource        (FM_SIZE+8)
 #define        kkDest          (FM_SIZE+12)
 #define        kkCountPtr      (FM_SIZE+16)
 #define        kkR31Save       (FM_SIZE+20)
+#define        kkThrErrJmp     (FM_SIZE+24)
  
  
 // nonvolatile CR bits we use as flags in cr3
@@ -492,20 +498,21 @@ pmap_novmx_icache_flush:
 /*
  * int
  * copyoutstr(src, dst, maxcount, count)
- *     vm_offset_t     src;
- *     vm_offset_t     dst;
- *     vm_size_t       maxcount; 
- *     vm_size_t*      count;
+ *     vm_offset_t     src;        // r3
+ *     addr64_t        dst;        // r4 and r5
+ *     vm_size_t       maxcount;   // r6
+ *     vm_size_t*      count;      // r7
  *
  * Set *count to the number of bytes copied.
  */
 
 ENTRY(copyoutstr, TAG_NO_FRAME_USED)
-        mfcr   r2                                                              // we use nonvolatile cr3
+        mfcr   r2,0x10                         // save caller's cr3, which we use for flags
+        mr      r10,r4                          // move high word of 64-bit user address to r10
         li             r0,0
         crset  kkString                                                // flag as a string op
-        mr             r10,r4                                                  // for copyout, dest ptr (r4) is in user space
-        stw            r0,0(r6)                                                // initialize #bytes moved
+        mr      r11,r5                          // move low word of 64-bit user address to r11
+        stw            r0,0(r7)                                                // initialize #bytes moved
         crclr  kkIn                                                    // flag as copyout
         b              copyJoin
 
@@ -514,10 +521,10 @@ ENTRY(copyoutstr, TAG_NO_FRAME_USED)
 /*
  * int
  * copyinstr(src, dst, maxcount, count)
- *     vm_offset_t     src;
- *     vm_offset_t     dst;
- *     vm_size_t       maxcount; 
- *     vm_size_t*      count;
+ *     addr64_t        src;        // r3 and r4
+ *     vm_offset_t     dst;        // r5
+ *     vm_size_t       maxcount;   // r6
+ *     vm_size_t*      count;      // r7
  *
  * Set *count to the number of bytes copied
  * If dst == NULL, don't copy, just count bytes.
@@ -525,13 +532,14 @@ ENTRY(copyoutstr, TAG_NO_FRAME_USED)
  */
 
 ENTRY(copyinstr, TAG_NO_FRAME_USED)
-        mfcr   r2                                                              // we use nonvolatile cr3
-        cmplwi r4,0                                                    // dst==NULL?
+        mfcr   r2,0x10                         // save caller's cr3, which we use for flags
+        cmplwi r5,0                                                    // dst==NULL?
+        mr      r10,r3                          // move high word of 64-bit user address to r10
         li             r0,0
         crset  kkString                                                // flag as a string op
-        mr             r10,r3                                                  // for copyin, source ptr (r3) is in user space
+        mr      r11,r4                          // move low word of 64-bit user address to r11
         crmove kkNull,cr0_eq                                   // remember if (dst==NULL)
-        stw            r0,0(r6)                                                // initialize #bytes moved
+        stw            r0,0(r7)                                                // initialize #bytes moved
         crset  kkIn                                                    // flag as copyin (rather than copyout)
         b              copyJoin1                                               // skip over the "crclr kkNull"
 
@@ -540,9 +548,9 @@ ENTRY(copyinstr, TAG_NO_FRAME_USED)
 /*
  * int
  * copyout(src, dst, count)
- *     vm_offset_t     src;
- *     vm_offset_t     dst;
- *     size_t          count;
+ *     vm_offset_t     src;        // r3
+ *     addr64_t        dst;        // r4 and r5
+ *     size_t          count;      // r6
  */
 
                        .align  5
@@ -553,18 +561,19 @@ LEXT(copyout)
 LEXT(copyoutmsg)
 
 #if INSTRUMENT
-                       mfspr   r12,pmc1                                                ; INSTRUMENT - saveinstr[12] - Take stamp at copyout
-                       stw             r12,0x6100+(12*16)+0x0(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc2                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(12*16)+0x4(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc3                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(12*16)+0x8(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc4                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(12*16)+0xC(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc1                                                ; INSTRUMENT - saveinstr[12] - Take stamp at copyout
+        stw            r12,0x6100+(12*16)+0x0(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc2                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(12*16)+0x4(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc3                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(12*16)+0x8(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc4                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(12*16)+0xC(0)               ; INSTRUMENT - Save it
 #endif                 
-        mfcr   r2                                                              // save caller's CR
+        mfcr   r2,0x10                         // save caller's cr3, which we use for flags
+        mr      r10,r4                          // move high word of 64-bit user address to r10
         crclr  kkString                                                // not a string version
-        mr             r10,r4                                                  // dest (r4) is user-space ptr
+        mr      r11,r5                          // move low word of 64-bit user address to r11
         crclr  kkIn                                                    // flag as copyout
         b              copyJoin
         
@@ -573,9 +582,9 @@ LEXT(copyoutmsg)
 /*
  * int
  * copyin(src, dst, count)
- *     vm_offset_t     src;
- *     vm_offset_t     dst;
- *     size_t          count;
+ *     addr64_t        src;        // r3 and r4
+ *     vm_offset_t     dst;        // r5
+ *     size_t          count;      // r6
  */
 
 
@@ -586,36 +595,41 @@ LEXT(copyoutmsg)
 LEXT(copyin)
 LEXT(copyinmsg)
 
-        mfcr   r2                                                              // save caller's CR
+        mfcr   r2,0x10                         // save caller's cr3, which we use for flags
+        mr      r10,r3                          // move high word of 64-bit user address to r10
         crclr  kkString                                                // not a string version
-        mr             r10,r3                                                  // source (r3) is user-space ptr in copyin
+        mr      r11,r4                          // move low word of 64-bit user address to r11
         crset  kkIn                                                    // flag as copyin
         
         
 // Common code to handle setup for all the copy variants:
-//             r2 = caller's CR, since we use cr3
-//   r3-r6 = parameters
-//        r10 = user-space ptr (r3 if copyin, r4 if copyout)
+//             r2 = caller's cr3
+//      r3 = source if copyout
+//      r5 = dest if copyin
+//      r6 = buffer length or count
+//      r7 = count output ptr (if kkString set)
+//        r10 = high word of 64-bit user-space address (source if copyin, dest if copyout)
+//        r11 = low word of 64-bit user-space address
 //     cr3 = kkIn, kkString, kkNull flags
 
 copyJoin:
         crclr  kkNull                                                  // (dst==NULL) convention not used with this call
 copyJoin1:                                                                             // enter from copyinstr with kkNull set
                mflr    r0                                                              // get return address
-        cmplwi r5,0                                                    // buffer length 0?
+        cmplwi r6,0                                                    // buffer length 0?
         lis            r9,0x1000                                               // r9 <- 0x10000000 (256MB)
                stw             r0,FM_LR_SAVE(r1)                               // save return
-        cmplw  cr1,r5,r9                                               // buffer length > 256MB ?
+        cmplw  cr1,r6,r9                                               // buffer length > 256MB ?
         mfsprg r8,2                                                    // get the features
         beq--  copyinout_0                                             // 0 length is degenerate case
                stwu    r1,-kkFrameSize(r1)                             // set up stack frame
-        stw            r2,kkCR(r1)                                             // save caller's CR since we use cr3
+        stw            r2,kkCR3(r1)                    // save caller's cr3, which we use for flags
         mtcrf  0x02,r8                                                 // move pf64Bit to cr6
-        stw            r3,kkSource(r1)                                 // save args across MapUserAddressSpace
-        stw            r4,kkDest(r1)
-        stw            r5,kkBufSize(r1)
+        stw            r3,kkSource(r1)                                 // save args across MapUserMemoryWindow
+        stw            r5,kkDest(r1)
+        stw            r6,kkBufSize(r1)
         crmove kk64bit,pf64Bitb                                // remember if this is a 64-bit processor
-        stw            r6,kkCountPtr(r1)
+        stw            r7,kkCountPtr(r1)
         stw            r31,kkR31Save(r1)                               // we use r31 globally for mapped user ptr
         li             r31,0                                                   // no mapped ptr yet
         
@@ -624,58 +638,60 @@ copyJoin1:                                                                                // enter from copyinstr with kkNull set
 // The string ops are passed -1 lengths by some BSD callers, so for them we silently clamp
 // the buffer length to 256MB.  This isn't an issue if the string is less than 256MB
 // (as most are!), but if they are >256MB we eventually return ENAMETOOLONG.  This restriction
-// is due to MapUserAddressSpace; we don't want to consume more than two segments for
+// is due to MapUserMemoryWindow; we don't want to consume more than two segments for
 // the mapping. 
 
         ble++  cr1,copyin0                                             // skip if buffer length <= 256MB
         bf             kkString,copyinout_too_big              // error if not string op
-        mr             r5,r9                                                   // silently clamp buffer length to 256MB
+        mr             r6,r9                                                   // silently clamp buffer length to 256MB
         stw            r9,kkBufSize(r1)                                // update saved copy too
 
 
 // Set up thread_recover in case we hit an illegal address.
 
 copyin0:
-               mfsprg  r8,1                                                    /* Get the current act */ 
+               mfsprg  r8,1                                                    // Get the current thread 
                lis             r2,hi16(copyinout_error)
-               lwz             r7,ACT_THREAD(r8)
                ori             r2,r2,lo16(copyinout_error)
+               lwz             r4,THREAD_RECOVER(r8)
                lwz             r3,ACT_VMMAP(r8)                                // r3 <- vm_map virtual address
-               stw             r2,THREAD_RECOVER(r7)
+               stw             r2,THREAD_RECOVER(r8)
+               stw             r4,kkThrErrJmp(r1)
 
 
-// Map user segment into kernel map, turn on 64-bit mode.
+// Map user segment into kernel map, turn on 64-bit mode.  At this point:
 //             r3 = vm map
-//             r5 = buffer length
-//        r10 = user space ptr (r3 if copyin, r4 if copyout)
+//             r6 = buffer length
+// r10/r11 = 64-bit user-space ptr (source if copyin, dest if copyout)
+//
+// When we call MapUserMemoryWindow, we pass:
+//      r3 = vm map ptr
+//   r4/r5 = 64-bit user space address as an addr64_t
         
-               mr              r6,r5                                                   // Set length to map
-               li              r4,0                                                    // Note: we only do this 32-bit for now
-        mr             r5,r10                                                  // arg2 <- user space ptr
+        mr      r4,r10                          // copy user ptr into r4/r5
+        mr      r5,r11
 #if INSTRUMENT
-                       mfspr   r12,pmc1                                                ; INSTRUMENT - saveinstr[13] - Take stamp before mapuseraddressspace
-                       stw             r12,0x6100+(13*16)+0x0(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc2                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(13*16)+0x4(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc3                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(13*16)+0x8(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc4                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(13*16)+0xC(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc1                                                ; INSTRUMENT - saveinstr[13] - Take stamp before mapuseraddressspace
+        stw            r12,0x6100+(13*16)+0x0(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc2                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(13*16)+0x4(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc3                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(13*16)+0x8(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc4                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(13*16)+0xC(0)               ; INSTRUMENT - Save it
 #endif                 
-        bl             EXT(MapUserAddressSpace)                // set r3 <- address in kernel map of user operand
+        bl             EXT(MapUserMemoryWindow)                // get r3/r4 <- 64-bit address in kernel map of user operand
 #if INSTRUMENT
-                       mfspr   r12,pmc1                                                ; INSTRUMENT - saveinstr[14] - Take stamp after mapuseraddressspace
-                       stw             r12,0x6100+(14*16)+0x0(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc2                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(14*16)+0x4(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc3                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(14*16)+0x8(0)               ; INSTRUMENT - Save it
-                       mfspr   r12,pmc4                                                ; INSTRUMENT - Get stamp
-                       stw             r12,0x6100+(14*16)+0xC(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc1                                                ; INSTRUMENT - saveinstr[14] - Take stamp after mapuseraddressspace
+        stw            r12,0x6100+(14*16)+0x0(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc2                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(14*16)+0x4(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc3                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(14*16)+0x8(0)               ; INSTRUMENT - Save it
+        mfspr  r12,pmc4                                                ; INSTRUMENT - Get stamp
+        stw            r12,0x6100+(14*16)+0xC(0)               ; INSTRUMENT - Save it
 #endif                 
-               or.             r0,r3,r4                                                // Did we fail the mapping?
         mr             r31,r4                                                  // r31 <- mapped ptr into user space (may be 64-bit)
-        beq--  copyinout_error                                 // was 0, so there was an error making the mapping
         bf--   kk64bit,copyin1                                 // skip if a 32-bit processor
  
                rldimi  r31,r3,32,0                                             // slam high-order bits into mapped ptr
@@ -691,7 +707,7 @@ copyin0:
 copyin1:
         lwz            r5,kkBufSize(r1)                                // restore length to copy
         bf             kkIn,copyin2                                    // skip if copyout
-        lwz            r4,kkDest(r1)                                   // copyin: source is mapped, dest is r4 at entry
+        lwz            r4,kkDest(r1)                                   // copyin: dest is kernel ptr
         mr             r3,r31                                                  // source is mapped ptr
         b              copyin3
 copyin2:                                                                               // handle copyout
@@ -703,7 +719,7 @@ copyin2:                                                                            // handle copyout
 //             r3 = source ptr (mapped if copyin)
 //             r4 = dest ptr (mapped if copyout)
 //             r5 = length
-//        r31 = mapped ptr returned by MapUserAddressSpace
+//        r31 = mapped ptr returned by MapUserMemoryWindow
 //        cr3 = kkIn, kkString, kk64bit, and kkNull flags
 
 copyin3:
@@ -714,29 +730,24 @@ copyin3:
         
 // Main exit point for copyin, copyout, copyinstr, and copyoutstr.  Also reached
 // from error recovery if we get a DSI accessing user space.  Clear recovery ptr, 
-// and pop off frame.  Note that we have kept
-// the mapped ptr into user space in r31, as a reg64_t type (ie, a 64-bit ptr on
-// 64-bit machines.)  We must unpack r31 into an addr64_t in (r3,r4) before passing
-// it to ReleaseUserAddressSpace.
+// and pop off frame.
 //             r3 = 0, EFAULT, or ENAMETOOLONG
 
 copyinx: 
-        lwz            r2,kkCR(r1)                                             // get callers cr3
-               mfsprg  r6,1                                                    // Get the current act 
-               lwz             r10,ACT_THREAD(r6)
-               
+        lwz            r2,kkCR3(r1)                    // get callers cr3
+               mfsprg  r6,1                                                    // Get the current thread 
         bf--   kk64bit,copyinx1                                // skip if 32-bit processor
         mfmsr  r12
         rldicl r12,r12,0,MSR_SF_BIT+1                  // if 64-bit processor, turn 64-bit mode off
-        mtmsrd r12                                                             // turn SF off and EE back on
+        mtmsrd r12                                                             // turn SF off
         isync                                                                  // wait for the mode to change
 copyinx1:
+               lwz             r0,FM_LR_SAVE+kkFrameSize(r1)   // get return address
         lwz            r31,kkR31Save(r1)                               // restore callers r31
+        lwz            r4,kkThrErrJmp(r1)                              // load saved thread recover
         addi   r1,r1,kkFrameSize                               // pop off our stack frame
-               lwz             r0,FM_LR_SAVE(r1)
-               li              r4,0
-               stw             r4,THREAD_RECOVER(r10)                  // Clear recovery
                mtlr    r0
+               stw             r4,THREAD_RECOVER(r6)                   // restore thread recover
         mtcrf  0x10,r2                                                 // restore cr3
                blr
 
@@ -770,55 +781,85 @@ copyinout_too_big:                                                                // degenerate case
 //             r3 = source ptr, mapped if copyinstr
 //             r4 = dest ptr, mapped if copyoutstr
 //             r5 = buffer length
-//        r31 = mapped ptr returned by MapUserAddressSpace
+//        r31 = mapped ptr returned by MapUserMemoryWindow
 //     cr3 = kkIn, kkString, kkNull, and kk64bit flags
 // We do word copies unless the buffer is very short, then use a byte copy loop
-// for the leftovers if necessary.
+// for the leftovers if necessary.  The crossover at which the word loop becomes
+// faster is about seven bytes, counting the zero.
+//
+// We first must word-align the source ptr, in order to avoid taking a spurious
+// page fault.
 
 copyString:
-        li             r12,0                                                   // Set header bytes count to zero
-        cmplwi cr1,r5,20                                               // is buffer very short?
+        cmplwi cr1,r5,15                                               // is buffer very short?
+        mr      r12,r3                          // remember ptr to 1st source byte
         mtctr  r5                                                              // assuming short, set up loop count for bytes
-        blt            cr1,copyinstr8                                  // too short for word loop
-        andi.  r12,r3,0x3                                              // is source ptr word aligned?
-        bne            copyinstr11                                             //  bytes loop
-copyinstr1:
-        srwi   r6,r5,2                                                 // get #words in buffer
-        mtctr  r6                                                              // set up word loop count
+        blt--   cr1,copyinstr8                                 // too short for word loop
+        rlwinm  r2,r3,0,0x3                     // get byte offset of 1st byte within word
+        rlwinm  r9,r3,3,0x18                    // get bit offset of 1st byte within word
+        li      r7,-1
+        sub     r3,r3,r2                        // word-align source address
+        add     r6,r5,r2                        // get length starting at byte 0 in word
+        srw     r7,r7,r9                        // get mask for bytes in first word
+        srwi   r0,r6,2                                                 // get #words in buffer
+        lwz     r5,0(r3)                        // get aligned word with first source byte
         lis            r10,hi16(0xFEFEFEFF)                    // load magic constants into r10 and r11
         lis            r11,hi16(0x80808080)
+        mtctr  r0                                                              // set up word loop count
+        addi    r3,r3,4                         // advance past the source word
         ori            r10,r10,lo16(0xFEFEFEFF)
         ori            r11,r11,lo16(0x80808080)
-        bf             kkNull,copyinstr6                               // enter loop that copies
-        b              copyinstr5                                              // use loop that just counts
+        orc     r8,r5,r7                        // map bytes preceeding first source byte into 0xFF
+        bt--   kkNull,copyinstr5enter          // enter loop that just counts
+        
+// Special case 1st word, which has been 0xFF filled on left.  Note that we use
+// "and.", even though we execute both in 32 and 64-bit mode.  This is OK.
+
+        slw     r5,r5,r9                        // left justify payload bytes
+        add            r9,r10,r8                                               // r9 =  data + 0xFEFEFEFF
+        andc   r7,r11,r8                                               // r7 = ~data & 0x80808080
+               subfic  r0,r2,4                                                 // get r0 <- #payload bytes in 1st word
+        and.    r7,r9,r7                                               // if r7==0, then all bytes in r8 are nonzero
+        stw     r5,0(r4)                        // copy payload bytes to dest buffer
+        add            r4,r4,r0                                                // then point to next byte in dest buffer
+        bdnzt   cr0_eq,copyinstr6               // use loop that copies if 0 not found
+        
+        b              copyinstr7                      // 0 found (buffer can't be full)
         
         
 // Word loop(s).  They do a word-parallel search for 0s, using the following
 // inobvious but very efficient test:
 //             y =  data + 0xFEFEFEFF
 //             z = ~data & 0x80808080
-// If (y & z)==0, then all bytes in dataword are nonzero.  We need two copies of
-// this loop, since if we test kkNull in the loop then it becomes 9 words long.
+// If (y & z)==0, then all bytes in dataword are nonzero.  There are two copies
+// of this loop, one that just counts and another that copies.
+//             r3 = ptr to next word of source (word aligned)
+//             r4 = ptr to next byte in buffer
+//      r6 = original buffer length (adjusted to be word origin)
+//     r10 = 0xFEFEFEFE
+//     r11 = 0x80808080
+//     r12 = ptr to 1st source byte (used to determine string length)
 
         .align 5                                                               // align inner loops for speed
 copyinstr5:                                                                            // version that counts but does not copy
-        lwz            r8,0(r3)                                                // get next word of source
-        addi   r3,r3,4                                                 // increment source ptr
+        lwz     r8,0(r3)                                               // get next word of source
+        addi    r3,r3,4                         // advance past it
+copyinstr5enter:
         add            r9,r10,r8                                               // r9 =  data + 0xFEFEFEFF
         andc   r7,r11,r8                                               // r7 = ~data & 0x80808080
-        and.   r7,r9,r7                                                // r7 = r9 & r7
-        bdnzt  cr0_eq,copyinstr5                               // if r7==0, then all bytes are nonzero
+        and.    r7,r9,r7                        // r7 = r9 & r7 ("." ok even in 64-bit mode)
+        bdnzt   cr0_eq,copyinstr5                              // if r7==0, then all bytes in r8 are nonzero
 
         b              copyinstr7
 
         .align 5                                                               // align inner loops for speed
 copyinstr6:                                                                            // version that counts and copies
-        lwz            r8,0(r3)                                                // get next word of source
-        addi   r3,r3,4                                                 // increment source ptr
+        lwz     r8,0(r3)                                               // get next word of source
+        addi    r3,r3,4                         // advance past it
         addi   r4,r4,4                                                 // increment dest ptr while we wait for data
         add            r9,r10,r8                                               // r9 =  data + 0xFEFEFEFF
         andc   r7,r11,r8                                               // r7 = ~data & 0x80808080
-        and.   r7,r9,r7                                                // r7 = r9 & r7
+        and.    r7,r9,r7                        // r7 = r9 & r7 ("." ok even in 64-bit mode)
         stw            r8,-4(r4)                                               // pack all 4 bytes into buffer
         bdnzt  cr0_eq,copyinstr6                               // if r7==0, then all bytes are nonzero
 
@@ -826,19 +867,24 @@ copyinstr6:                                                                               // version that counts and copies
 // Either 0 found or buffer filled.  The above algorithm has mapped nonzero bytes to 0
 // and 0 bytes to 0x80 with one exception: 0x01 bytes preceeding the first 0 are also
 // mapped to 0x80.  We must mask out these false hits before searching for an 0x80 byte.
+//             r3 = word aligned ptr to next word of source (ie, r8==mem(r3-4))
+//      r6 = original buffer length (adjusted to be word origin)
+//      r7 = computed vector of 0x00 and 0x80 bytes
+//      r8 = original source word, coming from -4(r3), possibly padded with 0xFFs on left if 1st word
+//     r12 = ptr to 1st source byte (used to determine string length)
+//     cr0 = beq set iff 0 not found
 
 copyinstr7:
-        crnot  kkZero,cr0_eq                                   // 0 found iff cr0_eq is off
-        mfctr  r6                                                              // get #words remaining in buffer
         rlwinm r2,r8,7,0,31                                    // move 0x01 bits to 0x80 position
-        slwi   r6,r6,2                                                 // convert to #bytes remaining
+               rlwinm  r6,r6,0,0x3                                             // mask down to partial byte count in last word
         andc   r7,r7,r2                                                // turn off false hits from 0x0100 worst case
-        rlwimi r6,r5,0,30,31                                   // add in odd bytes leftover in buffer
-        srwi   r7,r7,8                                                 // we want to count the 0 as a byte xferred
-        addi   r6,r6,4                                                 // don't count last word xferred (yet)
+        crnot  kkZero,cr0_eq                                   // 0 found iff cr0_eq is off
+        srwi    r7,r7,8                         // we want to count the 0 as a byte xferred
+               cmpwi   r6,0                                                    // any bytes left over in last word?
         cntlzw r7,r7                                                   // now we can find the 0 byte (ie, the 0x80)
+        subi    r3,r3,4                         // back up r3 to point to 1st byte in r8
         srwi   r7,r7,3                                                 // convert 8,16,24,32 to 1,2,3,4
-        sub.   r6,r6,r7                                                // account for nonzero bytes in last word
+        add     r3,r3,r7                        // now r3 points one past 0 byte, or at 1st byte not xferred
         bt++   kkZero,copyinstr10                              // 0 found, so done
         
         beq            copyinstr10                                             // r6==0, so buffer truly full
@@ -848,6 +894,10 @@ copyinstr7:
 
 // Byte loop.  This is used for very small buffers and for the odd bytes left over
 // after searching and copying words at a time.
+//      r3 = ptr to next byte of source
+//      r4 = ptr to next dest byte
+//     r12 = ptr to first byte of source
+//     ctr = count of bytes to check
     
         .align 5                                                               // align inner loops for speed
 copyinstr8:                                                                            // loop over bytes of source
@@ -855,53 +905,400 @@ copyinstr8:                                                                              // loop over bytes of source
         addi   r3,r3,1
         addi   r4,r4,1                                                 // increment dest addr whether we store or not
         cmpwi  r0,0                                                    // the 0?
-        bt--   kkNull,copyinstr9                               // don't store (was copyinstr with NULL ptr)
+        bt--   kkNull,copyinstr9                               // don't store if copyinstr with NULL ptr
         stb            r0,-1(r4)
 copyinstr9:
         bdnzf  cr0_eq,copyinstr8                               // loop if byte not 0 and more room in buffer
         
-        mfctr  r6                                                              // get #bytes left in buffer
         crmove kkZero,cr0_eq                                   // remember if 0 found or buffer filled
 
         
 // Buffer filled or 0 found.  Unwind and return.
-//     r5 = kkBufSize, ie buffer length
-//  r6 = untransferred bytes remaining in buffer
-// r31 = mapped ptr returned by MapUserAddressSpace
-// cr3 = kkZero set iff 0 found
+//      r3 = ptr to 1st source byte not transferred
+//     r12 = ptr to 1st source byte
+//     r31 = mapped ptr returned by MapUserMemoryWindow
+//     cr3 = kkZero set iff 0 found
 
 copyinstr10:
         lwz            r9,kkCountPtr(r1)                               // get ptr to place to store count of bytes moved
-        sub            r2,r5,r6                                                // get #bytes we moved, counting the 0 iff any
-        add            r2,r2,r12                                               // add the header bytes count
-        li             r3,0                                                    // assume 0 return status
+        sub     r2,r3,r12                       // compute #bytes copied (including the 0)
+        li             r3,0                                                    // assume success return status
         stw            r2,0(r9)                                                // store #bytes moved
         bt++   kkZero,copyinx                                  // we did find the 0 so return 0
         li             r3,ENAMETOOLONG                                 // buffer filled
         b              copyinx                                                 // join main exit routine
 
-// Byte loop.  This is used on the header bytes for unaligned source 
-    
-        .align 5                                                               // align inner loops for speed
-copyinstr11:
-        li             r10,4                                                   // load word size
-        sub            r12,r10,r12                                             // set the header bytes count
-        mtctr  r12                                                             // set up bytes loop count
-copyinstr12:                                                                   // loop over bytes of source
-        lbz            r0,0(r3)                                                // get next byte of source
-        addi   r3,r3,1
-        addi   r4,r4,1                                                 // increment dest addr whether we store or not
-        cmpwi  r0,0                                                    // the 0?
-        bt--   kkNull,copyinstr13                              // don't store (was copyinstr with NULL ptr)
-        stb            r0,-1(r4)
-copyinstr13:
-        bdnzf  cr0_eq,copyinstr12                              // loop if byte not 0 and more room in buffer
-        sub            r5,r5,r12                                               // substract the bytes copied
-        bne            cr0_eq,copyinstr1                               // branch to word loop
-
-        mr             r5,r12                                                  // Get the header bytes count
-        li             r12,0                                                   // Clear the header bytes count
-        mfctr  r6                                                              // get #bytes left in buffer
-        crmove kkZero,cr0_eq                                   // remember if 0 found or buffer filled
-        b              copyinstr10
+//<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+/*
+ * int
+ * copypv(source, sink, size, which)
+ *     addr64_t        src;        // r3 and r4
+ *     addr64_t        dst;        // r5 and r6
+ *     size_t          size;           // r7
+ *     int                     which;          // r8
+ *
+ * Operand size bytes are copied from operand src into operand dst. The source and
+ * destination operand addresses are given as addr64_t, and may designate starting
+ * locations in physical or virtual memory in any combination except where both are
+ * virtual. Virtual memory locations may be in either the kernel or the current thread's
+ * address space. Operand size may be up to 256MB.
+ *
+ * Operation is controlled by operand which, which offers these options:
+ *             cppvPsrc : source operand is (1) physical or (0) virtual
+ *             cppvPsnk : destination operand is (1) physical or (0) virtual
+ *             cppvKmap : virtual operand is in (1) kernel or (0) current thread
+ *             cppvFsnk : (1) flush destination before and after transfer
+ *             cppvFsrc : (1) flush source before and after transfer
+ *             cppvNoModSnk : (1) don't set source operand's changed bit(s)
+ *             cppvNoRefSrc : (1) don't set destination operand's referenced bit(s)
+ *
+ * Implementation is now split into this new 64-bit path and the old path, hw_copypv_32().
+ * This section describes the operation of the new 64-bit path.
+ *
+ * The 64-bit path utilizes the more capacious 64-bit kernel address space to create a
+ * window in the kernel address space into all of physical RAM plus the I/O hole. Since
+ * the window's mappings specify the proper access policies for the underlying memory,
+ * the new path does not have to flush caches to avoid a cache paradox, so cppvFsnk
+ * and cppvFsrc are ignored. Physical operand adresses are relocated into the physical
+ * memory window, and are accessed with data relocation on. Virtual addresses are either
+ * within the kernel, or are mapped into the kernel address space through the user memory
+ * window. Because accesses to a virtual operand are performed with data relocation on,
+ * the new path does not have to translate the address, disable/enable interrupts, lock
+ * the mapping, or update referenced and changed bits.
+ *
+ * The IBM 970 (a.k.a. G5) processor treats real-mode accesses as guarded, so there is
+ * a substantial performance penalty for copypv operating in real mode. Utilizing the
+ * new 64-bit path, transfer performance increases >100% on the G5.
+ *
+ * The attentive reader may notice that mtmsrd ops are not followed by isync ops as 
+ * might be expected. The 970 follows PowerPC architecture version 2.01, which defines
+ * mtmsrd with L=0 as a context synchronizing op, so a following isync is no longer
+ * required.
+ *
+ * To keep things exciting, we develop 64-bit values in non-volatiles, but we also need
+ * to call 32-bit functions, which would lead to the high-order 32 bits of our values
+ * getting clobbered unless we do something special. So, we preserve our 64-bit non-volatiles
+ * in our own stack frame across calls to 32-bit functions.
+ *             
+ */
 
+// Map operand which bits into non-volatile CR2 and CR3 bits.
+#define whichAlign     ((3+1)*4)
+#define whichMask      0x007F0000
+#define pvPsnk         (cppvPsnkb - whichAlign)
+#define pvPsrc         (cppvPsrcb - whichAlign)
+#define pvFsnk         (cppvFsnkb - whichAlign)
+#define pvFsrc         (cppvFsrcb - whichAlign)
+#define pvNoModSnk     (cppvNoModSnkb - whichAlign)
+#define pvNoRefSrc     (cppvNoRefSrcb - whichAlign)
+#define pvKmap         (cppvKmapb - whichAlign)
+#define pvNoCache      cr2_lt
+
+               .align  5
+               .globl  EXT(copypv)
+
+LEXT(copypv)
+        mfsprg r10,2                                                   // get feature flags
+        mtcrf  0x02,r10                                                // we need to test pf64Bit
+        bt++   pf64Bitb,copypv_64                              // skip if 64-bit processor (only they take hint)
+        
+        b              EXT(hw_copypv_32)                               // carry on with 32-bit copypv
+
+// Push a 32-bit ABI-compliant stack frame and preserve all non-volatiles that we'll clobber.        
+copypv_64:
+               mfsprg  r9,1                                                    // get current thread
+               stwu    r1,-(FM_ALIGN((31-26+11)*4)+FM_SIZE)(r1)
+                                                                                               // allocate stack frame and link it
+               mflr    r0                                                              // get return address
+               mfcr    r10                                                             // get cr2 and cr3
+               lwz             r12,THREAD_RECOVER(r9)                  // get error callback
+               stw             r26,FM_ARG0+0x00(r1)                    // save non-volatile r26
+               stw             r27,FM_ARG0+0x04(r1)                    // save non-volatile r27
+               stw             r28,FM_ARG0+0x08(r1)                    // save non-volatile r28
+               stw             r29,FM_ARG0+0x0C(r1)                    // save non-volatile r29
+               stw             r30,FM_ARG0+0x10(r1)                    // save non-volatile r30
+               stw             r31,FM_ARG0+0x14(r1)                    // save non-volatile r31
+               stw             r12,FM_ARG0+0x20(r1)                    // save error callback
+               stw             r0,(FM_ALIGN((31-26+11)*4)+FM_SIZE+FM_LR_SAVE)(r1)
+                                                                                               // save return address
+               stw             r10,(FM_ALIGN((31-26+11)*4)+FM_SIZE+FM_CR_SAVE)(r1)
+                                                                                               // save non-volatile cr2 and cr3
+
+// Non-volatile register usage in this routine is:
+//     r26: saved msr image
+//     r27: current pmap_t / virtual source address
+//     r28: destination virtual address
+//     r29: source address
+//     r30: destination address
+//     r31: byte count to copy
+//     cr2/3: parameter 'which' bits
+
+               rlwinm  r8,r8,whichAlign,whichMask              // align and mask which bits
+               mr              r31,r7                                                  // copy size to somewhere non-volatile
+               mtcrf   0x20,r8                                                 // insert which bits into cr2 and cr3
+               mtcrf   0x10,r8                                                 // insert which bits into cr2 and cr3
+               rlwinm  r29,r3,0,1,0                                    // form source address high-order bits
+               rlwinm  r30,r5,0,1,0                                    // form destination address high-order bits
+               rlwimi  r29,r4,0,0,31                                   // form source address low-order bits
+               rlwimi  r30,r6,0,0,31                                   // form destination address low-order bits
+               crand   cr7_lt,pvPsnk,pvPsrc                    // are both operand addresses physical?
+               cntlzw  r0,r31                                                  // count leading zeroes in byte count
+               cror    cr7_eq,pvPsnk,pvPsrc                    // cr7_eq <- source or destination is physical
+               bf--    cr7_eq,copypv_einval                    // both operands may not be virtual
+               cmplwi  r0,4                                                    // byte count greater than or equal 256M (2**28)?
+               blt--   copypv_einval                                   // byte count too big, give EINVAL
+               cmplwi  r31,0                                                   // byte count zero?
+               beq--   copypv_zero                                             // early out
+               bt              cr7_lt,copypv_phys                              // both operand addresses are physical
+               mr              r28,r30                                                 // assume destination is virtual
+               bf              pvPsnk,copypv_dv                                // is destination virtual?
+               mr              r28,r29                                                 // no, so source must be virtual
+copypv_dv:
+               lis             r27,ha16(EXT(kernel_pmap))              // get kernel's pmap_t *, high-order
+               lwz             r27,lo16(EXT(kernel_pmap))(r27) // get kernel's pmap_t
+               bt              pvKmap,copypv_kern                              // virtual address in kernel map?
+               lwz             r3,ACT_VMMAP(r9)                                // get user's vm_map *
+               rldicl  r4,r28,32,32                                    // r4, r5 <- addr64_t virtual address 
+               rldicl  r5,r28,0,32
+               std             r29,FM_ARG0+0x30(r1)                    // preserve 64-bit r29 across 32-bit call
+               std             r30,FM_ARG0+0x38(r1)                    // preserve 64-bit r30 across 32-bit call
+               bl              EXT(MapUserMemoryWindow)                // map slice of user space into kernel space
+               ld              r29,FM_ARG0+0x30(r1)                    // restore 64-bit r29
+               ld              r30,FM_ARG0+0x38(r1)                    // restore 64-bit r30
+               rlwinm  r28,r3,0,1,0                                    // convert relocated addr64_t virtual address 
+               rlwimi  r28,r4,0,0,31                                   //  into a single 64-bit scalar
+copypv_kern:
+
+// Since we'll be accessing the virtual operand with data-relocation on, we won't need to 
+// update the referenced and changed bits manually after the copy. So, force the appropriate
+// flag bit on for the virtual operand.
+               crorc   pvNoModSnk,pvNoModSnk,pvPsnk    // for virtual dest, let hardware do ref/chg bits
+               crorc   pvNoRefSrc,pvNoRefSrc,pvPsrc    // for virtual source, let hardware do ref bit
+               
+// We'll be finding a mapping and looking at, so we need to disable 'rupts.
+               lis             r0,hi16(MASK(MSR_VEC))                  // get vector mask
+               ori             r0,r0,lo16(MASK(MSR_FP))                // insert fp mask
+               mfmsr   r26                                                             // save current msr
+               andc    r26,r26,r0                                              // turn off VEC and FP in saved copy
+               ori             r0,r0,lo16(MASK(MSR_EE))                // add EE to our mask
+               andc    r0,r26,r0                                               // disable EE in our new msr image
+               mtmsrd  r0                                                              // introduce new msr image
+
+// We're now holding the virtual operand's pmap_t in r27 and its virtual address in r28. We now
+// try to find a mapping corresponding to this address in order to determine whether the address
+// is cacheable. If we don't find a mapping, we can safely assume that the operand is cacheable
+// (a non-cacheable operand must be a block mapping, which will always exist); otherwise, we
+// examine the mapping's caching-inhibited bit.
+               mr              r3,r27                                                  // r3 <- pmap_t pmap
+               rldicl  r4,r28,32,32                                    // r4, r5 <- addr64_t va
+               rldicl  r5,r28,0,32
+               la              r6,FM_ARG0+0x18(r1)                             // r6 <- addr64_t *nextva
+               li              r7,1                                                    // r7 <- int full, search nested mappings
+               std             r26,FM_ARG0+0x28(r1)                    // preserve 64-bit r26 across 32-bit calls
+               std             r28,FM_ARG0+0x30(r1)                    // preserve 64-bit r28 across 32-bit calls
+               std             r29,FM_ARG0+0x38(r1)                    // preserve 64-bit r29 across 32-bit calls
+               std             r30,FM_ARG0+0x40(r1)                    // preserve 64-bit r30 across 32-bit calls
+               bl              EXT(mapping_find)                               // find mapping for virtual operand
+               mr.             r3,r3                                                   // did we find it?
+               beq             copypv_nomapping                                // nope, so we'll assume it's cacheable
+               lwz             r4,mpVAddr+4(r3)                                // get low half of virtual addr for hw flags
+               rlwinm. r4,r4,0,mpIb-32,mpIb-32                 // caching-inhibited bit set?
+               crnot   pvNoCache,cr0_eq                                // if it is, use bcopy_nc
+               bl              EXT(mapping_drop_busy)                  // drop busy on the mapping
+copypv_nomapping:
+               ld              r26,FM_ARG0+0x28(r1)                    // restore 64-bit r26
+               ld              r28,FM_ARG0+0x30(r1)                    // restore 64-bit r28
+               ld              r29,FM_ARG0+0x38(r1)                    // restore 64-bit r29
+               ld              r30,FM_ARG0+0x40(r1)                    // restore 64-bit r30
+               mtmsrd  r26                                                             // restore msr to it's previous state
+
+// Set both the source and destination virtual addresses to the virtual operand's address --
+// we'll overlay one of them with the physical operand's address.
+               mr              r27,r28                                                 // make virtual operand BOTH source AND destination
+
+// Now we're ready to relocate the physical operand address(es) into the physical memory window.
+// Recall that we've mapped physical memory (including the I/O hole) into the kernel's address
+// space somewhere at or over the 2**32 line. If one or both of the operands are in the I/O hole,
+// we'll set the pvNoCache flag, forcing use of non-caching bcopy_nc() to do the copy.
+copypv_phys:
+               ld              r6,lgPMWvaddr(0)                                // get physical memory window virtual address
+               bf              pvPsnk,copypv_dstvirt                   // is destination address virtual?
+               cntlzd  r4,r30                                                  // count leading zeros in destination address
+               cmplwi  r4,32                                                   // if it's 32, then it's in the I/O hole (2**30 to 2**31-1)
+               cror    pvNoCache,cr0_eq,pvNoCache              // use bcopy_nc for I/O hole locations          
+               add             r28,r30,r6                                              // relocate physical destination into physical window
+copypv_dstvirt:
+               bf              pvPsrc,copypv_srcvirt                   // is source address virtual?
+               cntlzd  r4,r29                                                  // count leading zeros in source address
+               cmplwi  r4,32                                                   // if it's 32, then it's in the I/O hole (2**30 to 2**31-1)
+               cror    pvNoCache,cr0_eq,pvNoCache              // use bcopy_nc for I/O hole locations          
+               add             r27,r29,r6                                              // relocate physical source into physical window
+copypv_srcvirt:
+
+// Once the copy is under way (bcopy or bcopy_nc), we will want to get control if anything
+// funny happens during the copy. So, we set a pointer to our error handler in the per-thread
+// control block.
+               mfsprg  r8,1                                                    // get current threads stuff
+               lis             r3,hi16(copypv_error)                   // get our error callback's address, high
+               ori             r3,r3,lo16(copypv_error)                // get our error callback's address, low
+               stw             r3,THREAD_RECOVER(r8)                   // set our error callback
+               
+// Since our physical operand(s) are relocated at or above the 2**32 line, we must enter
+// 64-bit mode.
+               li              r0,1                                                    // get a handy one bit
+               mfmsr   r3                                                              // get current msr
+               rldimi  r3,r0,63,MSR_SF_BIT                             // set SF bit on in our msr copy
+               mtmsrd  r3                                                              // enter 64-bit mode
+
+// If requested, flush data cache
+// Note that we don't flush, the code is being saved "just in case".
+#if 0
+               bf              pvFsrc,copypv_nfs                               // do we flush the source?
+               rldicl  r3,r27,32,32                                    // r3, r4 <- addr64_t source virtual address
+               rldicl  r4,r27,0,32
+               mr              r5,r31                                                  // r5 <- count (in bytes)
+               li              r6,0                                                    // r6 <- boolean phys (false, not physical)
+               bl              EXT(flush_dcache)                               // flush the source operand
+copypv_nfs:
+               bf              pvFsnk,copypv_nfdx                              // do we flush the destination?
+               rldicl  r3,r28,32,32                                    // r3, r4 <- addr64_t destination virtual address
+               rldicl  r4,r28,0,32
+               mr              r5,r31                                                  // r5 <- count (in bytes)
+               li              r6,0                                                    // r6 <- boolean phys (false, not physical)
+               bl              EXT(flush_dcache)                               // flush the destination operand
+copypv_nfdx:
+#endif
+
+// Call bcopy or bcopy_nc to perform the copy.
+               mr              r3,r27                                                  // r3 <- source virtual address
+               mr              r4,r28                                                  // r4 <- destination virtual address
+               mr              r5,r31                                                  // r5 <- bytes to copy
+               bt              pvNoCache,copypv_nc                             // take non-caching route
+               bl              EXT(bcopy)                                              // call bcopy to do the copying
+               b               copypv_copydone
+copypv_nc:
+               bl              EXT(bcopy_nc)                                   // call bcopy_nc to do the copying
+copypv_copydone:
+
+// If requested, flush data cache
+// Note that we don't flush, the code is being saved "just in case".
+#if 0
+               bf              pvFsrc,copypv_nfsx                              // do we flush the source?
+               rldicl  r3,r27,32,32                                    // r3, r4 <- addr64_t source virtual address
+               rldicl  r4,r27,0,32
+               mr              r5,r31                                                  // r5 <- count (in bytes)
+               li              r6,0                                                    // r6 <- boolean phys (false, not physical)
+               bl              EXT(flush_dcache)                               // flush the source operand
+copypv_nfsx:
+               bf              pvFsnk,copypv_nfd                               // do we flush the destination?
+               rldicl  r3,r28,32,32                                    // r3, r4 <- addr64_t destination virtual address
+               rldicl  r4,r28,0,32
+               mr              r5,r31                                                  // r5 <- count (in bytes)
+               li              r6,0                                                    // r6 <- boolean phys (false, not physical)
+               bl              EXT(flush_dcache)                               // flush the destination operand
+copypv_nfd:
+#endif
+
+// Leave 64-bit mode.
+               mfmsr   r3                                                              // get current msr
+               rldicl  r3,r3,0,MSR_SF_BIT+1                    // clear SF bit in our copy
+               mtmsrd  r3                                                              // leave 64-bit mode
+
+// If requested, set ref/chg on source/dest physical operand(s). It is possible that copy is
+// from/to a RAM disk situated outside of mapped physical RAM, so we check each page by calling
+// mapping_phys_lookup() before we try to set its ref/chg bits; otherwise, we might panic.
+// Note that this code is page-size sensitive, so it should probably be a part of our low-level
+// code in hw_vm.s.
+               bt              pvNoModSnk,copypv_nomod                 // skip destination update if not requested
+               std             r29,FM_ARG0+0x30(r1)                    // preserve 64-bit r29 across 32-bit calls
+               li              r26,1                                                   // r26 <- 4K-page count                                         
+               mr              r27,r31                                                 // r27 <- byte count
+               rlwinm  r3,r30,0,20,31                                  // does destination cross a page boundary?
+               subfic  r3,r3,4096                                              //
+               cmplw   r3,r27                                                  // 
+               blt             copypv_modnox                                   // skip if not crossing case
+               subf    r27,r3,r27                                              // r27 <- byte count less initial fragment
+               addi    r26,r26,1                                               // increment page count
+copypv_modnox:
+               srdi    r3,r27,12                                               // pages to update (not including crosser)
+               add             r26,r26,r3                                              // add in crosser
+               srdi    r27,r30,12                                              // r27 <- destination page number
+copypv_modloop:
+               mr              r3,r27                                                  // r3 <- destination page number                                
+               la              r4,FM_ARG0+0x18(r1)                             // r4 <- unsigned int *pindex
+               bl              EXT(mapping_phys_lookup)                // see if page is really there
+               mr.             r3,r3                                                   // is it?
+               beq--   copypv_modend                                   // nope, break out of modify loop
+               mr              r3,r27                                                  // r3 <- destination page number
+               bl              EXT(mapping_set_mod)                    // set page changed status
+               subi    r26,r26,1                                               // decrement page count
+               cmpwi   r26,0                                                   // done yet?
+               bgt             copypv_modloop                                  // nope, iterate
+copypv_modend:
+               ld              r29,FM_ARG0+0x30(r1)                    // restore 64-bit r29
+copypv_nomod:
+               bt              pvNoRefSrc,copypv_done                  // skip source update if not requested
+copypv_debugref:
+               li              r26,1                                                   // r26 <- 4K-page count                                         
+               mr              r27,r31                                                 // r27 <- byte count
+               rlwinm  r3,r29,0,20,31                                  // does source cross a page boundary?
+               subfic  r3,r3,4096                                              //
+               cmplw   r3,r27                                                  // 
+               blt             copypv_refnox                                   // skip if not crossing case
+               subf    r27,r3,r27                                              // r27 <- byte count less initial fragment
+               addi    r26,r26,1                                               // increment page count
+copypv_refnox:
+               srdi    r3,r27,12                                               // pages to update (not including crosser)
+               add             r26,r26,r3                                              // add in crosser
+               srdi    r27,r29,12                                              // r27 <- source page number
+copypv_refloop:
+               mr              r3,r27                                                  // r3 <- source page number
+               la              r4,FM_ARG0+0x18(r1)                             // r4 <- unsigned int *pindex
+               bl              EXT(mapping_phys_lookup)                // see if page is really there
+               mr.             r3,r3                                                   // is it?
+               beq--   copypv_done                                             // nope, break out of modify loop
+               mr              r3,r27                                                  // r3 <- source  page number
+               bl              EXT(mapping_set_ref)                    // set page referenced status
+               subi    r26,r26,1                                               // decrement page count
+               cmpwi   r26,0                                                   // done yet?
+               bgt             copypv_refloop                                  // nope, iterate
+               
+// Return, indicating success.
+copypv_done:
+copypv_zero:
+               li              r3,0                                                    // our efforts were crowned with success
+
+// Pop frame, restore caller's non-volatiles, clear recovery routine pointer.
+copypv_return:
+               mfsprg  r9,1                                                    // get current threads stuff
+               lwz             r0,(FM_ALIGN((31-26+11)*4)+FM_SIZE+FM_LR_SAVE)(r1)
+                                                                                               // get return address
+               lwz             r4,(FM_ALIGN((31-26+11)*4)+FM_SIZE+FM_CR_SAVE)(r1)
+                                                                                               // get non-volatile cr2 and cr3
+               lwz             r26,FM_ARG0+0x00(r1)                    // restore non-volatile r26
+               lwz             r27,FM_ARG0+0x04(r1)                    // restore non-volatile r27
+               mtlr    r0                                                              // restore return address
+               lwz             r28,FM_ARG0+0x08(r1)                    // restore non-volatile r28
+               mtcrf   0x20,r4                                                 // restore non-volatile cr2
+               mtcrf   0x10,r4                                                 // restore non-volatile cr3
+               lwz             r11,FM_ARG0+0x20(r1)                    // save error callback
+               lwz             r29,FM_ARG0+0x0C(r1)                    // restore non-volatile r29
+               lwz             r30,FM_ARG0+0x10(r1)                    // restore non-volatile r30
+               lwz             r31,FM_ARG0+0x14(r1)                    // restore non-volatile r31
+               stw             r11,THREAD_RECOVER(r9)                  // restore our error callback
+               lwz             r1,0(r1)                                                // release stack frame
+                                                                                               
+               blr                                                                             // y'all come back now
+
+// Invalid argument handler.
+copypv_einval:
+               li              r3,EINVAL                                               // invalid argument
+               b               copypv_return                                   // return
+
+// Error encountered during bcopy or bcopy_nc.         
+copypv_error:
+               mfmsr   r3                                                              // get current msr
+               rldicl  r3,r3,0,MSR_SF_BIT+1                    // clear SF bit in our copy
+               mtmsrd  r3                                                              // leave 64-bit mode
+               li              r3,EFAULT                                               // it was all his fault
+               b               copypv_return                                   // return