xserver mesa git update 4 July 2011

1 files changed, 745 insertions, 745 deletions

diff --git a/xorg-server/exa/exa_migration_classic.c b/xorg-server/exa/exa_migration_classic.c
index 5ec2ac0b8..dd3cd491e 100644
--- a/xorg-server/exa/exa_migration_classic.c
+++ b/xorg-server/exa/exa_migration_classic.c
@@ -1,745 +1,745 @@
-/*

- * Copyright © 2006 Intel Corporation

- *

- * Permission is hereby granted, free of charge, to any person obtaining a

- * copy of this software and associated documentation files (the "Software"),

- * to deal in the Software without restriction, including without limitation

- * the rights to use, copy, modify, merge, publish, distribute, sublicense,

- * and/or sell copies of the Software, and to permit persons to whom the

- * Software is furnished to do so, subject to the following conditions:

- *

- * The above copyright notice and this permission notice (including the next

- * paragraph) shall be included in all copies or substantial portions of the

- * Software.

- *

- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

- * SOFTWARE.

- *

- * Authors:

- *    Eric Anholt <eric@anholt.net>

- *    Michel Dänzer <michel@tungstengraphics.com>

- *

- */

-

-#ifdef HAVE_DIX_CONFIG_H

-#include <dix-config.h>

-#endif

-

-#include <string.h>

-

-#include "exa_priv.h"

-#include "exa.h"

-

-#if DEBUG_MIGRATE

-#define DBG_MIGRATE(a) ErrorF a

-#else

-#define DBG_MIGRATE(a)

-#endif

-

-/**

- * The fallback path for UTS/DFS failing is to just memcpy.  exaCopyDirtyToSys

- * and exaCopyDirtyToFb both needed to do this loop.

- */

-static void

-exaMemcpyBox (PixmapPtr pPixmap, BoxPtr pbox, CARD8 *src, int src_pitch,

-	      CARD8 *dst, int dst_pitch)

- {

-    int i, cpp = pPixmap->drawable.bitsPerPixel / 8;

-    int bytes = (pbox->x2 - pbox->x1) * cpp;

-

-    src += pbox->y1 * src_pitch + pbox->x1 * cpp;

-    dst += pbox->y1 * dst_pitch + pbox->x1 * cpp;

-

-    for (i = pbox->y2 - pbox->y1; i; i--) {

-	memcpy (dst, src, bytes);

-	src += src_pitch;

-	dst += dst_pitch;

-    }

-}

-

-/**

- * Returns TRUE if the pixmap is dirty (has been modified in its current

- * location compared to the other), or lacks a private for tracking

- * dirtiness.

- */

-static Bool

-exaPixmapIsDirty (PixmapPtr pPix)

-{

-    ExaPixmapPriv (pPix);

-

-    if (pExaPixmap == NULL)

-	EXA_FatalErrorDebugWithRet(("EXA bug: exaPixmapIsDirty was called on a non-exa pixmap.\n"), TRUE);

-

-    if (!pExaPixmap->pDamage)

-	return FALSE;

-

-    return RegionNotEmpty(DamageRegion(pExaPixmap->pDamage)) ||

-	!RegionEqual(&pExaPixmap->validSys, &pExaPixmap->validFB);

-}

-

-/**

- * Returns TRUE if the pixmap is either pinned in FB, or has a sufficient score

- * to be considered "should be in framebuffer".  That's just anything that has

- * had more acceleration than fallbacks, or has no score yet.

- *

- * Only valid if using a migration scheme that tracks score.

- */

-static Bool

-exaPixmapShouldBeInFB (PixmapPtr pPix)

-{

-    ExaPixmapPriv (pPix);

-

-    if (exaPixmapIsPinned (pPix))

-	return TRUE;

-

-    return pExaPixmap->score >= 0;

-}

-

-/**

- * If the pixmap is currently dirty, this copies at least the dirty area from

- * FB to system or vice versa.  Both areas must be allocated.

- */

-static void

-exaCopyDirty(ExaMigrationPtr migrate, RegionPtr pValidDst, RegionPtr pValidSrc,

-	     Bool (*transfer) (PixmapPtr pPix, int x, int y, int w, int h,

-			       char *sys, int sys_pitch), int fallback_index,

-	     void (*sync) (ScreenPtr pScreen))

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaPixmapPriv (pPixmap);

-    RegionPtr damage = DamageRegion (pExaPixmap->pDamage);

-    RegionRec CopyReg;

-    Bool save_use_gpu_copy;

-    int save_pitch;

-    BoxPtr pBox;

-    int nbox;

-    Bool access_prepared = FALSE;

-    Bool need_sync = FALSE;

-

-    /* Damaged bits are valid in current copy but invalid in other one */

-    if (pExaPixmap->use_gpu_copy) {

-	RegionUnion(&pExaPixmap->validFB, &pExaPixmap->validFB,

-		     damage);

-	RegionSubtract(&pExaPixmap->validSys, &pExaPixmap->validSys,

-			damage);

-    } else {

-	RegionUnion(&pExaPixmap->validSys, &pExaPixmap->validSys,

-		     damage);

-	RegionSubtract(&pExaPixmap->validFB, &pExaPixmap->validFB,

-			damage);

-    }

-

-    RegionEmpty(damage);

-

-    /* Copy bits valid in source but not in destination */

-    RegionNull(&CopyReg);

-    RegionSubtract(&CopyReg, pValidSrc, pValidDst);

-

-    if (migrate->as_dst) {

-	ExaScreenPriv (pPixmap->drawable.pScreen);

-

-	/* XXX: The pending damage region will be marked as damaged after the

-	 * operation, so it should serve as an upper bound for the region that

-	 * needs to be synchronized for the operation. Unfortunately, this

-	 * causes corruption in some cases, e.g. when starting compiz. See

-	 * https://bugs.freedesktop.org/show_bug.cgi?id=12916 .

-	 */

-	if (pExaScr->optimize_migration) {

-	    RegionPtr pending_damage = DamagePendingRegion(pExaPixmap->pDamage);

-

-#if DEBUG_MIGRATE

-	    if (RegionNil(pending_damage)) {

-		static Bool firsttime = TRUE;

-

-		if (firsttime) {

-		    ErrorF("%s: Pending damage region empty!\n", __func__);

-		    firsttime = FALSE;

-		}

-	    }

-#endif

-

-	    /* Try to prevent destination valid region from growing too many

-	     * rects by filling it up to the extents of the union of the

-	     * destination valid region and the pending damage region.

-	     */

-	    if (RegionNumRects(pValidDst) > 10) {

-		BoxRec box;

-		BoxPtr pValidExt, pDamageExt;

-		RegionRec closure;

-

-		pValidExt = RegionExtents(pValidDst);

-		pDamageExt = RegionExtents(pending_damage);

-

-		box.x1 = min(pValidExt->x1, pDamageExt->x1);

-		box.y1 = min(pValidExt->y1, pDamageExt->y1);

-		box.x2 = max(pValidExt->x2, pDamageExt->x2);

-		box.y2 = max(pValidExt->y2, pDamageExt->y2);

-

-		RegionInit(&closure, &box, 0);

-		RegionIntersect(&CopyReg, &CopyReg, &closure);

-	    } else

-		RegionIntersect(&CopyReg, &CopyReg, pending_damage);

-	}

-

-	/* The caller may provide a region to be subtracted from the calculated

-	 * dirty region. This is to avoid migration of bits that don't

-	 * contribute to the result of the operation.

-	 */

-	if (migrate->pReg)

-	    RegionSubtract(&CopyReg, &CopyReg, migrate->pReg);

-    } else {

-	/* The caller may restrict the region to be migrated for source pixmaps

-	 * to what's relevant for the operation.

-	 */

-	if (migrate->pReg)

-	    RegionIntersect(&CopyReg, &CopyReg, migrate->pReg);

-    }

-

-    pBox = RegionRects(&CopyReg);

-    nbox = RegionNumRects(&CopyReg);

-

-    save_use_gpu_copy = pExaPixmap->use_gpu_copy;

-    save_pitch = pPixmap->devKind;

-    pExaPixmap->use_gpu_copy = TRUE;

-    pPixmap->devKind = pExaPixmap->fb_pitch;

-

-    while (nbox--) {

-	pBox->x1 = max(pBox->x1, 0);

-	pBox->y1 = max(pBox->y1, 0);

-	pBox->x2 = min(pBox->x2, pPixmap->drawable.width);

-	pBox->y2 = min(pBox->y2, pPixmap->drawable.height);

-

-	if (pBox->x1 >= pBox->x2 || pBox->y1 >= pBox->y2)

-	    continue;

-

-	if (!transfer || !transfer (pPixmap,

-				    pBox->x1, pBox->y1,

-				    pBox->x2 - pBox->x1,

-				    pBox->y2 - pBox->y1,

-				    (char *) (pExaPixmap->sys_ptr

-				    + pBox->y1 * pExaPixmap->sys_pitch

-				    + pBox->x1 * pPixmap->drawable.bitsPerPixel / 8),

-				    pExaPixmap->sys_pitch))

-	{

-	    if (!access_prepared) {

-		ExaDoPrepareAccess(pPixmap, fallback_index);

-		access_prepared = TRUE;

-	    }

-	    if (fallback_index == EXA_PREPARE_DEST) {

-		exaMemcpyBox (pPixmap, pBox,

-			      pExaPixmap->sys_ptr, pExaPixmap->sys_pitch,

-			      pPixmap->devPrivate.ptr, pPixmap->devKind);

-	    } else {

-		exaMemcpyBox (pPixmap, pBox,

-			      pPixmap->devPrivate.ptr, pPixmap->devKind,

-			      pExaPixmap->sys_ptr, pExaPixmap->sys_pitch);

-	    }

-	} else

-	    need_sync = TRUE;

-

-	pBox++;

-    }

-

-    pExaPixmap->use_gpu_copy = save_use_gpu_copy;

-    pPixmap->devKind = save_pitch;

-

-    /* Try to prevent source valid region from growing too many rects by

-     * removing parts of it which are also in the destination valid region.

-     * Removing anything beyond that would lead to data loss.

-     */

-    if (RegionNumRects(pValidSrc) > 20)

-	RegionSubtract(pValidSrc, pValidSrc, pValidDst);

-

-    /* The copied bits are now valid in destination */

-    RegionUnion(pValidDst, pValidDst, &CopyReg);

-

-    RegionUninit(&CopyReg);

-

-    if (access_prepared)

-	exaFinishAccess(&pPixmap->drawable, fallback_index);

-    else if (need_sync && sync)

-	sync (pPixmap->drawable.pScreen);

-}

-

-/**

- * If the pixmap is currently dirty, this copies at least the dirty area from

- * the framebuffer  memory copy to the system memory copy.  Both areas must be

- * allocated.

- */

-void

-exaCopyDirtyToSys (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaScreenPriv (pPixmap->drawable.pScreen);

-    ExaPixmapPriv (pPixmap);

-

-    exaCopyDirty(migrate, &pExaPixmap->validSys, &pExaPixmap->validFB,

-		 pExaScr->info->DownloadFromScreen, EXA_PREPARE_SRC,

-		 exaWaitSync);

-}

-

-/**

- * If the pixmap is currently dirty, this copies at least the dirty area from

- * the system memory copy to the framebuffer memory copy.  Both areas must be

- * allocated.

- */

-void

-exaCopyDirtyToFb (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaScreenPriv (pPixmap->drawable.pScreen);

-    ExaPixmapPriv (pPixmap);

-

-    exaCopyDirty(migrate, &pExaPixmap->validFB, &pExaPixmap->validSys,

-		 pExaScr->info->UploadToScreen, EXA_PREPARE_DEST, NULL);

-}

-

-/**

- * Allocates a framebuffer copy of the pixmap if necessary, and then copies

- * any necessary pixmap data into the framebuffer copy and points the pixmap at

- * it.

- *

- * Note that when first allocated, a pixmap will have FALSE dirty flag.

- * This is intentional because pixmap data starts out undefined.  So if we move

- * it in due to the first operation against it being accelerated, it will have

- * undefined framebuffer contents that we didn't have to upload.  If we do

- * moveouts (and moveins) after the first movein, then we will only have to copy

- * back and forth if the pixmap was written to after the last synchronization of

- * the two copies.  Then, at exaPixmapSave (when the framebuffer copy goes away)

- * we mark the pixmap dirty, so that the next exaMoveInPixmap will actually move

- * all the data, since it's almost surely all valid now.

- */

-static void

-exaDoMoveInPixmap (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ScreenPtr pScreen = pPixmap->drawable.pScreen;

-    ExaScreenPriv (pScreen);

-    ExaPixmapPriv (pPixmap);

-

-    /* If we're VT-switched away, no touching card memory allowed. */

-    if (pExaScr->swappedOut)

-	return;

-

-    /* If we're not allowed to move, then fail. */

-    if (exaPixmapIsPinned(pPixmap))

-	return;

-

-    /* Don't migrate in pixmaps which are less than 8bpp.  This avoids a lot of

-     * fragility in EXA, and <8bpp is probably not used enough any more to care

-     * (at least, not in acceleratd paths).

-     */

-    if (pPixmap->drawable.bitsPerPixel < 8)

-	return;

-

-    if (pExaPixmap->accel_blocked)

-	return;

-

-    if (pExaPixmap->area == NULL) {

-	pExaPixmap->area =

-	    exaOffscreenAlloc (pScreen, pExaPixmap->fb_size,

-			       pExaScr->info->pixmapOffsetAlign, FALSE,

-                               exaPixmapSave, (pointer) pPixmap);

-	if (pExaPixmap->area == NULL)

-	    return;

-

-	pExaPixmap->fb_ptr = (CARD8 *) pExaScr->info->memoryBase +

-				       pExaPixmap->area->offset;

-    }

-

-    exaCopyDirtyToFb (migrate);

-

-    if (exaPixmapHasGpuCopy(pPixmap))

-	return;

-

-    DBG_MIGRATE (("-> %p (0x%x) (%dx%d) (%c)\n", pPixmap,

-		  (ExaGetPixmapPriv(pPixmap)->area ?

-                   ExaGetPixmapPriv(pPixmap)->area->offset : 0),

-		  pPixmap->drawable.width,

-		  pPixmap->drawable.height,

-		  exaPixmapIsDirty(pPixmap) ? 'd' : 'c'));

-

-    pExaPixmap->use_gpu_copy = TRUE;

-

-    pPixmap->devKind = pExaPixmap->fb_pitch;

-    pPixmap->drawable.serialNumber = NEXT_SERIAL_NUMBER;

-}

-

-void

-exaMoveInPixmap_classic (PixmapPtr pPixmap)

-{

-    static ExaMigrationRec migrate = { .as_dst = FALSE, .as_src = TRUE,

-				       .pReg = NULL };

-

-    migrate.pPix = pPixmap;

-    exaDoMoveInPixmap (&migrate);

-}

-

-/**

- * Switches the current active location of the pixmap to system memory, copying

- * updated data out if necessary.

- */

-static void

-exaDoMoveOutPixmap (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaPixmapPriv (pPixmap);

-

-    if (!pExaPixmap->area || exaPixmapIsPinned(pPixmap))

-	return;

-

-    exaCopyDirtyToSys (migrate);

-

-    if (exaPixmapHasGpuCopy(pPixmap)) {

-

-	DBG_MIGRATE (("<- %p (%p) (%dx%d) (%c)\n", pPixmap,

-		      (void*)(ExaGetPixmapPriv(pPixmap)->area ?

-			      ExaGetPixmapPriv(pPixmap)->area->offset : 0),

-		      pPixmap->drawable.width,

-		      pPixmap->drawable.height,

-		      exaPixmapIsDirty(pPixmap) ? 'd' : 'c'));

-

-	pExaPixmap->use_gpu_copy = FALSE;

-

-	pPixmap->devKind = pExaPixmap->sys_pitch;

-	pPixmap->drawable.serialNumber = NEXT_SERIAL_NUMBER;

-    }

-}

-

-void

-exaMoveOutPixmap_classic (PixmapPtr pPixmap)

-{

-    static ExaMigrationRec migrate = { .as_dst = FALSE, .as_src = TRUE,

-				       .pReg = NULL };

-

-    migrate.pPix = pPixmap;

-    exaDoMoveOutPixmap (&migrate);

-}

-

-

-/**

- * Copies out important pixmap data and removes references to framebuffer area.

- * Called when the memory manager decides it's time to kick the pixmap out of

- * framebuffer entirely.

- */

-void

-exaPixmapSave (ScreenPtr pScreen, ExaOffscreenArea *area)

-{

-    PixmapPtr pPixmap = area->privData;

-    ExaPixmapPriv(pPixmap);

-

-    exaMoveOutPixmap(pPixmap);

-

-    pExaPixmap->fb_ptr = NULL;

-    pExaPixmap->area = NULL;

-

-    /* Mark all FB bits as invalid, so all valid system bits get copied to FB

-     * next time */

-    RegionEmpty(&pExaPixmap->validFB);

-}

-

-/**

- * For the "greedy" migration scheme, pushes the pixmap toward being located in

- * framebuffer memory.

- */

-static void

-exaMigrateTowardFb (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaPixmapPriv (pPixmap);

-

-    if (pExaPixmap->score == EXA_PIXMAP_SCORE_PINNED) {

-	DBG_MIGRATE(("UseScreen: not migrating pinned pixmap %p\n",

-		     (pointer)pPixmap));

-	return;

-    }

-

-    DBG_MIGRATE(("UseScreen %p score %d\n",

-		 (pointer)pPixmap, pExaPixmap->score));

-

-    if (pExaPixmap->score == EXA_PIXMAP_SCORE_INIT) {

-	exaDoMoveInPixmap(migrate);

-	pExaPixmap->score = 0;

-    }

-

-    if (pExaPixmap->score < EXA_PIXMAP_SCORE_MAX)

-	pExaPixmap->score++;

-

-    if (pExaPixmap->score >= EXA_PIXMAP_SCORE_MOVE_IN &&

-	!exaPixmapHasGpuCopy(pPixmap))

-    {

-	exaDoMoveInPixmap(migrate);

-    }

-

-    if (exaPixmapHasGpuCopy(pPixmap)) {

-	exaCopyDirtyToFb (migrate);

-	ExaOffscreenMarkUsed (pPixmap);

-    } else

-	exaCopyDirtyToSys (migrate);

-}

-

-/**

- * For the "greedy" migration scheme, pushes the pixmap toward being located in

- * system memory.

- */

-static void

-exaMigrateTowardSys (ExaMigrationPtr migrate)

-{

-    PixmapPtr pPixmap = migrate->pPix;

-    ExaPixmapPriv (pPixmap);

-

-    DBG_MIGRATE(("UseMem: %p score %d\n", (pointer)pPixmap, pExaPixmap->score));

-

-    if (pExaPixmap->score == EXA_PIXMAP_SCORE_PINNED)

-	return;

-

-    if (pExaPixmap->score == EXA_PIXMAP_SCORE_INIT)

-	pExaPixmap->score = 0;

-

-    if (pExaPixmap->score > EXA_PIXMAP_SCORE_MIN)

-	pExaPixmap->score--;

-

-    if (pExaPixmap->score <= EXA_PIXMAP_SCORE_MOVE_OUT && pExaPixmap->area)

-	exaDoMoveOutPixmap(migrate);

-

-    if (exaPixmapHasGpuCopy(pPixmap)) {

-	exaCopyDirtyToFb (migrate);

-	ExaOffscreenMarkUsed (pPixmap);

-    } else

-	exaCopyDirtyToSys (migrate);

-}

-

-/**

- * If the pixmap has both a framebuffer and system memory copy, this function

- * asserts that both of them are the same.

- */

-static Bool

-exaAssertNotDirty (PixmapPtr pPixmap)

-{

-    ExaPixmapPriv (pPixmap);

-    CARD8 *dst, *src;

-    RegionRec ValidReg;

-    int dst_pitch, src_pitch, cpp, y, nbox, save_pitch;

-    BoxPtr pBox;

-    Bool ret = TRUE, save_use_gpu_copy;

-

-    if (exaPixmapIsPinned(pPixmap) || pExaPixmap->area == NULL)

-	return ret;

-

-    RegionNull(&ValidReg);

-    RegionIntersect(&ValidReg, &pExaPixmap->validFB,

-		     &pExaPixmap->validSys);

-    nbox = RegionNumRects(&ValidReg);

-

-    if (!nbox)

-	goto out;

-

-    pBox = RegionRects(&ValidReg);

-

-    dst_pitch = pExaPixmap->sys_pitch;

-    src_pitch = pExaPixmap->fb_pitch;

-    cpp = pPixmap->drawable.bitsPerPixel / 8;

-

-    save_use_gpu_copy = pExaPixmap->use_gpu_copy;

-    save_pitch = pPixmap->devKind;

-    pExaPixmap->use_gpu_copy = TRUE;

-    pPixmap->devKind = pExaPixmap->fb_pitch;

-

-    if (!ExaDoPrepareAccess(pPixmap, EXA_PREPARE_SRC))

-	goto skip;

-

-    while (nbox--) {

-	    int rowbytes;

-

-	    pBox->x1 = max(pBox->x1, 0);

-	    pBox->y1 = max(pBox->y1, 0);

-	    pBox->x2 = min(pBox->x2, pPixmap->drawable.width);

-	    pBox->y2 = min(pBox->y2, pPixmap->drawable.height);

-

-	    if (pBox->x1 >= pBox->x2 || pBox->y1 >= pBox->y2)

-		continue;

-

-	    rowbytes = (pBox->x2 - pBox->x1) * cpp;

-	    src = (CARD8 *) pPixmap->devPrivate.ptr + pBox->y1 * src_pitch + pBox->x1 * cpp;

-	    dst = pExaPixmap->sys_ptr + pBox->y1 * dst_pitch + pBox->x1 * cpp;

-

-	    for (y = pBox->y1; y < pBox->y2;

-		 y++, src += src_pitch, dst += dst_pitch) {

-		if (memcmp(dst, src, rowbytes) != 0) {

-		    ret = FALSE;

-		    exaPixmapDirty(pPixmap, pBox->x1, pBox->y1, pBox->x2,

-				   pBox->y2);

-		    break;

-		}

-	    }

-    }

-

-skip:

-    exaFinishAccess(&pPixmap->drawable, EXA_PREPARE_SRC);

-

-    pExaPixmap->use_gpu_copy = save_use_gpu_copy;

-    pPixmap->devKind = save_pitch;

-

-out:

-    RegionUninit(&ValidReg);

-    return ret;

-}

-

-/**

- * Performs migration of the pixmaps according to the operation information

- * provided in pixmaps and can_accel and the migration scheme chosen in the

- * config file.

- */

-void

-exaDoMigration_classic (ExaMigrationPtr pixmaps, int npixmaps, Bool can_accel)

-{

-    ScreenPtr pScreen = pixmaps[0].pPix->drawable.pScreen;

-    ExaScreenPriv(pScreen);

-    int i, j;

-

-    /* If this debugging flag is set, check each pixmap for whether it is marked

-     * as clean, and if so, actually check if that's the case.  This should help

-     * catch issues with failing to mark a drawable as dirty.  While it will

-     * catch them late (after the operation happened), it at least explains what

-     * went wrong, and instrumenting the code to find what operation happened

-     * to the pixmap last shouldn't be hard.

-     */

-    if (pExaScr->checkDirtyCorrectness) {

-	for (i = 0; i < npixmaps; i++) {

-	    if (!exaPixmapIsDirty (pixmaps[i].pPix) &&

-		!exaAssertNotDirty (pixmaps[i].pPix))

-		ErrorF("%s: Pixmap %d dirty but not marked as such!\n", __func__, i);

-	}

-    }

-    /* If anything is pinned in system memory, we won't be able to

-     * accelerate.

-     */

-    for (i = 0; i < npixmaps; i++) {

-	if (exaPixmapIsPinned (pixmaps[i].pPix) &&

-	    !exaPixmapHasGpuCopy (pixmaps[i].pPix))

-	{

-	    EXA_FALLBACK(("Pixmap %p (%dx%d) pinned in sys\n", pixmaps[i].pPix,

-		      pixmaps[i].pPix->drawable.width,

-		      pixmaps[i].pPix->drawable.height));

-	    can_accel = FALSE;

-	    break;

-	}

-    }

-

-    if (pExaScr->migration == ExaMigrationSmart) {

-	/* If we've got something as a destination that we shouldn't cause to

-	 * become newly dirtied, take the unaccelerated route.

-	 */

-	for (i = 0; i < npixmaps; i++) {

-	    if (pixmaps[i].as_dst && !exaPixmapShouldBeInFB (pixmaps[i].pPix) &&

-		!exaPixmapIsDirty (pixmaps[i].pPix))

-	    {

-		for (i = 0; i < npixmaps; i++) {

-		    if (!exaPixmapIsDirty (pixmaps[i].pPix))

-			exaDoMoveOutPixmap (pixmaps + i);

-		}

-		return;

-	    }

-	}

-

-	/* If we aren't going to accelerate, then we migrate everybody toward

-	 * system memory, and kick out if it's free.

-	 */

-	if (!can_accel) {

-	    for (i = 0; i < npixmaps; i++) {

-		exaMigrateTowardSys (pixmaps + i);

-		if (!exaPixmapIsDirty (pixmaps[i].pPix))

-		    exaDoMoveOutPixmap (pixmaps + i);

-	    }

-	    return;

-	}

-

-	/* Finally, the acceleration path.  Move them all in. */

-	for (i = 0; i < npixmaps; i++) {

-	    exaMigrateTowardFb(pixmaps + i);

-	    exaDoMoveInPixmap(pixmaps + i);

-	}

-    } else if (pExaScr->migration == ExaMigrationGreedy) {

-	/* If we can't accelerate, either because the driver can't or because one of

-	 * the pixmaps is pinned in system memory, then we migrate everybody toward

-	 * system memory.

-	 *

-	 * We also migrate toward system if all pixmaps involved are currently in

-	 * system memory -- this can mitigate thrashing when there are significantly

-	 * more pixmaps active than would fit in memory.

-	 *

-	 * If not, then we migrate toward FB so that hopefully acceleration can

-	 * happen.

-	 */

-	if (!can_accel) {

-	    for (i = 0; i < npixmaps; i++)

-		exaMigrateTowardSys (pixmaps + i);

-	    return;

-	}

-

-	for (i = 0; i < npixmaps; i++) {

-	    if (exaPixmapHasGpuCopy(pixmaps[i].pPix)) {

-		/* Found one in FB, so move all to FB. */

-		for (j = 0; j < npixmaps; j++)

-		    exaMigrateTowardFb(pixmaps + i);

-		return;

-	    }

-	}

-

-	/* Nobody's in FB, so move all away from FB. */

-	for (i = 0; i < npixmaps; i++)

-	    exaMigrateTowardSys(pixmaps + i);

-    } else if (pExaScr->migration == ExaMigrationAlways) {

-	/* Always move the pixmaps out if we can't accelerate.  If we can

-	 * accelerate, try to move them all in.  If that fails, then move them

-	 * back out.

-	 */

-	if (!can_accel) {

-	    for (i = 0; i < npixmaps; i++)

-		exaDoMoveOutPixmap(pixmaps + i);

-	    return;

-	}

-

-	/* Now, try to move them all into FB */

-	for (i = 0; i < npixmaps; i++) {

-	    exaDoMoveInPixmap(pixmaps + i);

-	}

-

-	/* If we couldn't fit everything in, abort */

-	for (i = 0; i < npixmaps; i++) {

-	    if (!exaPixmapHasGpuCopy(pixmaps[i].pPix)) {

-		return;

-	    }

-	}

-

-	/* Yay, everything has a gpu copy, mark memory as used */

-	for (i = 0; i < npixmaps; i++) {

-	    ExaOffscreenMarkUsed (pixmaps[i].pPix);

-	}

-    }

-}

-

-void

-exaPrepareAccessReg_classic(PixmapPtr pPixmap, int index, RegionPtr pReg)

-{

-    ExaMigrationRec pixmaps[1];

-

-    if (index == EXA_PREPARE_DEST || index == EXA_PREPARE_AUX_DEST) {

-	pixmaps[0].as_dst = TRUE;

-	pixmaps[0].as_src = FALSE;

-    } else {

-	pixmaps[0].as_dst = FALSE;

-	pixmaps[0].as_src = TRUE;

-    }

-    pixmaps[0].pPix = pPixmap;

-    pixmaps[0].pReg = pReg;

-

-    exaDoMigration(pixmaps, 1, FALSE);

-

-    (void)ExaDoPrepareAccess(pPixmap, index);

-}

+/*
+ * Copyright © 2006 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ *    Eric Anholt <eric@anholt.net>
+ *    Michel Dänzer <michel@tungstengraphics.com>
+ *
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include <string.h>
+
+#include "exa_priv.h"
+#include "exa.h"
+
+#if DEBUG_MIGRATE
+#define DBG_MIGRATE(a) ErrorF a
+#else
+#define DBG_MIGRATE(a)
+#endif
+
+/**
+ * The fallback path for UTS/DFS failing is to just memcpy.  exaCopyDirtyToSys
+ * and exaCopyDirtyToFb both needed to do this loop.
+ */
+static void
+exaMemcpyBox (PixmapPtr pPixmap, BoxPtr pbox, CARD8 *src, int src_pitch,
+	      CARD8 *dst, int dst_pitch)
+ {
+    int i, cpp = pPixmap->drawable.bitsPerPixel / 8;
+    int bytes = (pbox->x2 - pbox->x1) * cpp;
+
+    src += pbox->y1 * src_pitch + pbox->x1 * cpp;
+    dst += pbox->y1 * dst_pitch + pbox->x1 * cpp;
+
+    for (i = pbox->y2 - pbox->y1; i; i--) {
+	memcpy (dst, src, bytes);
+	src += src_pitch;
+	dst += dst_pitch;
+    }
+}
+
+/**
+ * Returns TRUE if the pixmap is dirty (has been modified in its current
+ * location compared to the other), or lacks a private for tracking
+ * dirtiness.
+ */
+static Bool
+exaPixmapIsDirty (PixmapPtr pPix)
+{
+    ExaPixmapPriv (pPix);
+
+    if (pExaPixmap == NULL)
+	EXA_FatalErrorDebugWithRet(("EXA bug: exaPixmapIsDirty was called on a non-exa pixmap.\n"), TRUE);
+
+    if (!pExaPixmap->pDamage)
+	return FALSE;
+
+    return RegionNotEmpty(DamageRegion(pExaPixmap->pDamage)) ||
+	!RegionEqual(&pExaPixmap->validSys, &pExaPixmap->validFB);
+}
+
+/**
+ * Returns TRUE if the pixmap is either pinned in FB, or has a sufficient score
+ * to be considered "should be in framebuffer".  That's just anything that has
+ * had more acceleration than fallbacks, or has no score yet.
+ *
+ * Only valid if using a migration scheme that tracks score.
+ */
+static Bool
+exaPixmapShouldBeInFB (PixmapPtr pPix)
+{
+    ExaPixmapPriv (pPix);
+
+    if (exaPixmapIsPinned (pPix))
+	return TRUE;
+
+    return pExaPixmap->score >= 0;
+}
+
+/**
+ * If the pixmap is currently dirty, this copies at least the dirty area from
+ * FB to system or vice versa.  Both areas must be allocated.
+ */
+static void
+exaCopyDirty(ExaMigrationPtr migrate, RegionPtr pValidDst, RegionPtr pValidSrc,
+	     Bool (*transfer) (PixmapPtr pPix, int x, int y, int w, int h,
+			       char *sys, int sys_pitch), int fallback_index,
+	     void (*sync) (ScreenPtr pScreen))
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaPixmapPriv (pPixmap);
+    RegionPtr damage = DamageRegion (pExaPixmap->pDamage);
+    RegionRec CopyReg;
+    Bool save_use_gpu_copy;
+    int save_pitch;
+    BoxPtr pBox;
+    int nbox;
+    Bool access_prepared = FALSE;
+    Bool need_sync = FALSE;
+
+    /* Damaged bits are valid in current copy but invalid in other one */
+    if (pExaPixmap->use_gpu_copy) {
+	RegionUnion(&pExaPixmap->validFB, &pExaPixmap->validFB,
+		     damage);
+	RegionSubtract(&pExaPixmap->validSys, &pExaPixmap->validSys,
+			damage);
+    } else {
+	RegionUnion(&pExaPixmap->validSys, &pExaPixmap->validSys,
+		     damage);
+	RegionSubtract(&pExaPixmap->validFB, &pExaPixmap->validFB,
+			damage);
+    }
+
+    RegionEmpty(damage);
+
+    /* Copy bits valid in source but not in destination */
+    RegionNull(&CopyReg);
+    RegionSubtract(&CopyReg, pValidSrc, pValidDst);
+
+    if (migrate->as_dst) {
+	ExaScreenPriv (pPixmap->drawable.pScreen);
+
+	/* XXX: The pending damage region will be marked as damaged after the
+	 * operation, so it should serve as an upper bound for the region that
+	 * needs to be synchronized for the operation. Unfortunately, this
+	 * causes corruption in some cases, e.g. when starting compiz. See
+	 * https://bugs.freedesktop.org/show_bug.cgi?id=12916 .
+	 */
+	if (pExaScr->optimize_migration) {
+	    RegionPtr pending_damage = DamagePendingRegion(pExaPixmap->pDamage);
+
+#if DEBUG_MIGRATE
+	    if (RegionNil(pending_damage)) {
+		static Bool firsttime = TRUE;
+
+		if (firsttime) {
+		    ErrorF("%s: Pending damage region empty!\n", __func__);
+		    firsttime = FALSE;
+		}
+	    }
+#endif
+
+	    /* Try to prevent destination valid region from growing too many
+	     * rects by filling it up to the extents of the union of the
+	     * destination valid region and the pending damage region.
+	     */
+	    if (RegionNumRects(pValidDst) > 10) {
+		BoxRec box;
+		BoxPtr pValidExt, pDamageExt;
+		RegionRec closure;
+
+		pValidExt = RegionExtents(pValidDst);
+		pDamageExt = RegionExtents(pending_damage);
+
+		box.x1 = min(pValidExt->x1, pDamageExt->x1);
+		box.y1 = min(pValidExt->y1, pDamageExt->y1);
+		box.x2 = max(pValidExt->x2, pDamageExt->x2);
+		box.y2 = max(pValidExt->y2, pDamageExt->y2);
+
+		RegionInit(&closure, &box, 0);
+		RegionIntersect(&CopyReg, &CopyReg, &closure);
+	    } else
+		RegionIntersect(&CopyReg, &CopyReg, pending_damage);
+	}
+
+	/* The caller may provide a region to be subtracted from the calculated
+	 * dirty region. This is to avoid migration of bits that don't
+	 * contribute to the result of the operation.
+	 */
+	if (migrate->pReg)
+	    RegionSubtract(&CopyReg, &CopyReg, migrate->pReg);
+    } else {
+	/* The caller may restrict the region to be migrated for source pixmaps
+	 * to what's relevant for the operation.
+	 */
+	if (migrate->pReg)
+	    RegionIntersect(&CopyReg, &CopyReg, migrate->pReg);
+    }
+
+    pBox = RegionRects(&CopyReg);
+    nbox = RegionNumRects(&CopyReg);
+
+    save_use_gpu_copy = pExaPixmap->use_gpu_copy;
+    save_pitch = pPixmap->devKind;
+    pExaPixmap->use_gpu_copy = TRUE;
+    pPixmap->devKind = pExaPixmap->fb_pitch;
+
+    while (nbox--) {
+	pBox->x1 = max(pBox->x1, 0);
+	pBox->y1 = max(pBox->y1, 0);
+	pBox->x2 = min(pBox->x2, pPixmap->drawable.width);
+	pBox->y2 = min(pBox->y2, pPixmap->drawable.height);
+
+	if (pBox->x1 >= pBox->x2 || pBox->y1 >= pBox->y2)
+	    continue;
+
+	if (!transfer || !transfer (pPixmap,
+				    pBox->x1, pBox->y1,
+				    pBox->x2 - pBox->x1,
+				    pBox->y2 - pBox->y1,
+				    (char *) (pExaPixmap->sys_ptr
+				    + pBox->y1 * pExaPixmap->sys_pitch
+				    + pBox->x1 * pPixmap->drawable.bitsPerPixel / 8),
+				    pExaPixmap->sys_pitch))
+	{
+	    if (!access_prepared) {
+		ExaDoPrepareAccess(pPixmap, fallback_index);
+		access_prepared = TRUE;
+	    }
+	    if (fallback_index == EXA_PREPARE_DEST) {
+		exaMemcpyBox (pPixmap, pBox,
+			      pExaPixmap->sys_ptr, pExaPixmap->sys_pitch,
+			      pPixmap->devPrivate.ptr, pPixmap->devKind);
+	    } else {
+		exaMemcpyBox (pPixmap, pBox,
+			      pPixmap->devPrivate.ptr, pPixmap->devKind,
+			      pExaPixmap->sys_ptr, pExaPixmap->sys_pitch);
+	    }
+	} else
+	    need_sync = TRUE;
+
+	pBox++;
+    }
+
+    pExaPixmap->use_gpu_copy = save_use_gpu_copy;
+    pPixmap->devKind = save_pitch;
+
+    /* Try to prevent source valid region from growing too many rects by
+     * removing parts of it which are also in the destination valid region.
+     * Removing anything beyond that would lead to data loss.
+     */
+    if (RegionNumRects(pValidSrc) > 20)
+	RegionSubtract(pValidSrc, pValidSrc, pValidDst);
+
+    /* The copied bits are now valid in destination */
+    RegionUnion(pValidDst, pValidDst, &CopyReg);
+
+    RegionUninit(&CopyReg);
+
+    if (access_prepared)
+	exaFinishAccess(&pPixmap->drawable, fallback_index);
+    else if (need_sync && sync)
+	sync (pPixmap->drawable.pScreen);
+}
+
+/**
+ * If the pixmap is currently dirty, this copies at least the dirty area from
+ * the framebuffer  memory copy to the system memory copy.  Both areas must be
+ * allocated.
+ */
+void
+exaCopyDirtyToSys (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaScreenPriv (pPixmap->drawable.pScreen);
+    ExaPixmapPriv (pPixmap);
+
+    exaCopyDirty(migrate, &pExaPixmap->validSys, &pExaPixmap->validFB,
+		 pExaScr->info->DownloadFromScreen, EXA_PREPARE_SRC,
+		 exaWaitSync);
+}
+
+/**
+ * If the pixmap is currently dirty, this copies at least the dirty area from
+ * the system memory copy to the framebuffer memory copy.  Both areas must be
+ * allocated.
+ */
+void
+exaCopyDirtyToFb (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaScreenPriv (pPixmap->drawable.pScreen);
+    ExaPixmapPriv (pPixmap);
+
+    exaCopyDirty(migrate, &pExaPixmap->validFB, &pExaPixmap->validSys,
+		 pExaScr->info->UploadToScreen, EXA_PREPARE_DEST, NULL);
+}
+
+/**
+ * Allocates a framebuffer copy of the pixmap if necessary, and then copies
+ * any necessary pixmap data into the framebuffer copy and points the pixmap at
+ * it.
+ *
+ * Note that when first allocated, a pixmap will have FALSE dirty flag.
+ * This is intentional because pixmap data starts out undefined.  So if we move
+ * it in due to the first operation against it being accelerated, it will have
+ * undefined framebuffer contents that we didn't have to upload.  If we do
+ * moveouts (and moveins) after the first movein, then we will only have to copy
+ * back and forth if the pixmap was written to after the last synchronization of
+ * the two copies.  Then, at exaPixmapSave (when the framebuffer copy goes away)
+ * we mark the pixmap dirty, so that the next exaMoveInPixmap will actually move
+ * all the data, since it's almost surely all valid now.
+ */
+static void
+exaDoMoveInPixmap (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ScreenPtr pScreen = pPixmap->drawable.pScreen;
+    ExaScreenPriv (pScreen);
+    ExaPixmapPriv (pPixmap);
+
+    /* If we're VT-switched away, no touching card memory allowed. */
+    if (pExaScr->swappedOut)
+	return;
+
+    /* If we're not allowed to move, then fail. */
+    if (exaPixmapIsPinned(pPixmap))
+	return;
+
+    /* Don't migrate in pixmaps which are less than 8bpp.  This avoids a lot of
+     * fragility in EXA, and <8bpp is probably not used enough any more to care
+     * (at least, not in acceleratd paths).
+     */
+    if (pPixmap->drawable.bitsPerPixel < 8)
+	return;
+
+    if (pExaPixmap->accel_blocked)
+	return;
+
+    if (pExaPixmap->area == NULL) {
+	pExaPixmap->area =
+	    exaOffscreenAlloc (pScreen, pExaPixmap->fb_size,
+			       pExaScr->info->pixmapOffsetAlign, FALSE,
+                               exaPixmapSave, (pointer) pPixmap);
+	if (pExaPixmap->area == NULL)
+	    return;
+
+	pExaPixmap->fb_ptr = (CARD8 *) pExaScr->info->memoryBase +
+				       pExaPixmap->area->offset;
+    }
+
+    exaCopyDirtyToFb (migrate);
+
+    if (exaPixmapHasGpuCopy(pPixmap))
+	return;
+
+    DBG_MIGRATE (("-> %p (0x%x) (%dx%d) (%c)\n", pPixmap,
+		  (ExaGetPixmapPriv(pPixmap)->area ?
+                   ExaGetPixmapPriv(pPixmap)->area->offset : 0),
+		  pPixmap->drawable.width,
+		  pPixmap->drawable.height,
+		  exaPixmapIsDirty(pPixmap) ? 'd' : 'c'));
+
+    pExaPixmap->use_gpu_copy = TRUE;
+
+    pPixmap->devKind = pExaPixmap->fb_pitch;
+    pPixmap->drawable.serialNumber = NEXT_SERIAL_NUMBER;
+}
+
+void
+exaMoveInPixmap_classic (PixmapPtr pPixmap)
+{
+    static ExaMigrationRec migrate = { .as_dst = FALSE, .as_src = TRUE,
+				       .pReg = NULL };
+
+    migrate.pPix = pPixmap;
+    exaDoMoveInPixmap (&migrate);
+}
+
+/**
+ * Switches the current active location of the pixmap to system memory, copying
+ * updated data out if necessary.
+ */
+static void
+exaDoMoveOutPixmap (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaPixmapPriv (pPixmap);
+
+    if (!pExaPixmap->area || exaPixmapIsPinned(pPixmap))
+	return;
+
+    exaCopyDirtyToSys (migrate);
+
+    if (exaPixmapHasGpuCopy(pPixmap)) {
+
+	DBG_MIGRATE (("<- %p (%p) (%dx%d) (%c)\n", pPixmap,
+		      (void*)(ExaGetPixmapPriv(pPixmap)->area ?
+			      ExaGetPixmapPriv(pPixmap)->area->offset : 0),
+		      pPixmap->drawable.width,
+		      pPixmap->drawable.height,
+		      exaPixmapIsDirty(pPixmap) ? 'd' : 'c'));
+
+	pExaPixmap->use_gpu_copy = FALSE;
+
+	pPixmap->devKind = pExaPixmap->sys_pitch;
+	pPixmap->drawable.serialNumber = NEXT_SERIAL_NUMBER;
+    }
+}
+
+void
+exaMoveOutPixmap_classic (PixmapPtr pPixmap)
+{
+    static ExaMigrationRec migrate = { .as_dst = FALSE, .as_src = TRUE,
+				       .pReg = NULL };
+
+    migrate.pPix = pPixmap;
+    exaDoMoveOutPixmap (&migrate);
+}
+
+
+/**
+ * Copies out important pixmap data and removes references to framebuffer area.
+ * Called when the memory manager decides it's time to kick the pixmap out of
+ * framebuffer entirely.
+ */
+void
+exaPixmapSave (ScreenPtr pScreen, ExaOffscreenArea *area)
+{
+    PixmapPtr pPixmap = area->privData;
+    ExaPixmapPriv(pPixmap);
+
+    exaMoveOutPixmap(pPixmap);
+
+    pExaPixmap->fb_ptr = NULL;
+    pExaPixmap->area = NULL;
+
+    /* Mark all FB bits as invalid, so all valid system bits get copied to FB
+     * next time */
+    RegionEmpty(&pExaPixmap->validFB);
+}
+
+/**
+ * For the "greedy" migration scheme, pushes the pixmap toward being located in
+ * framebuffer memory.
+ */
+static void
+exaMigrateTowardFb (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaPixmapPriv (pPixmap);
+
+    if (pExaPixmap->score == EXA_PIXMAP_SCORE_PINNED) {
+	DBG_MIGRATE(("UseScreen: not migrating pinned pixmap %p\n",
+		     (pointer)pPixmap));
+	return;
+    }
+
+    DBG_MIGRATE(("UseScreen %p score %d\n",
+		 (pointer)pPixmap, pExaPixmap->score));
+
+    if (pExaPixmap->score == EXA_PIXMAP_SCORE_INIT) {
+	exaDoMoveInPixmap(migrate);
+	pExaPixmap->score = 0;
+    }
+
+    if (pExaPixmap->score < EXA_PIXMAP_SCORE_MAX)
+	pExaPixmap->score++;
+
+    if (pExaPixmap->score >= EXA_PIXMAP_SCORE_MOVE_IN &&
+	!exaPixmapHasGpuCopy(pPixmap))
+    {
+	exaDoMoveInPixmap(migrate);
+    }
+
+    if (exaPixmapHasGpuCopy(pPixmap)) {
+	exaCopyDirtyToFb (migrate);
+	ExaOffscreenMarkUsed (pPixmap);
+    } else
+	exaCopyDirtyToSys (migrate);
+}
+
+/**
+ * For the "greedy" migration scheme, pushes the pixmap toward being located in
+ * system memory.
+ */
+static void
+exaMigrateTowardSys (ExaMigrationPtr migrate)
+{
+    PixmapPtr pPixmap = migrate->pPix;
+    ExaPixmapPriv (pPixmap);
+
+    DBG_MIGRATE(("UseMem: %p score %d\n", (pointer)pPixmap, pExaPixmap->score));
+
+    if (pExaPixmap->score == EXA_PIXMAP_SCORE_PINNED)
+	return;
+
+    if (pExaPixmap->score == EXA_PIXMAP_SCORE_INIT)
+	pExaPixmap->score = 0;
+
+    if (pExaPixmap->score > EXA_PIXMAP_SCORE_MIN)
+	pExaPixmap->score--;
+
+    if (pExaPixmap->score <= EXA_PIXMAP_SCORE_MOVE_OUT && pExaPixmap->area)
+	exaDoMoveOutPixmap(migrate);
+
+    if (exaPixmapHasGpuCopy(pPixmap)) {
+	exaCopyDirtyToFb (migrate);
+	ExaOffscreenMarkUsed (pPixmap);
+    } else
+	exaCopyDirtyToSys (migrate);
+}
+
+/**
+ * If the pixmap has both a framebuffer and system memory copy, this function
+ * asserts that both of them are the same.
+ */
+static Bool
+exaAssertNotDirty (PixmapPtr pPixmap)
+{
+    ExaPixmapPriv (pPixmap);
+    CARD8 *dst, *src;
+    RegionRec ValidReg;
+    int dst_pitch, src_pitch, cpp, y, nbox, save_pitch;
+    BoxPtr pBox;
+    Bool ret = TRUE, save_use_gpu_copy;
+
+    if (exaPixmapIsPinned(pPixmap) || pExaPixmap->area == NULL)
+	return ret;
+
+    RegionNull(&ValidReg);
+    RegionIntersect(&ValidReg, &pExaPixmap->validFB,
+		     &pExaPixmap->validSys);
+    nbox = RegionNumRects(&ValidReg);
+
+    if (!nbox)
+	goto out;
+
+    pBox = RegionRects(&ValidReg);
+
+    dst_pitch = pExaPixmap->sys_pitch;
+    src_pitch = pExaPixmap->fb_pitch;
+    cpp = pPixmap->drawable.bitsPerPixel / 8;
+
+    save_use_gpu_copy = pExaPixmap->use_gpu_copy;
+    save_pitch = pPixmap->devKind;
+    pExaPixmap->use_gpu_copy = TRUE;
+    pPixmap->devKind = pExaPixmap->fb_pitch;
+
+    if (!ExaDoPrepareAccess(pPixmap, EXA_PREPARE_SRC))
+	goto skip;
+
+    while (nbox--) {
+	    int rowbytes;
+
+	    pBox->x1 = max(pBox->x1, 0);
+	    pBox->y1 = max(pBox->y1, 0);
+	    pBox->x2 = min(pBox->x2, pPixmap->drawable.width);
+	    pBox->y2 = min(pBox->y2, pPixmap->drawable.height);
+
+	    if (pBox->x1 >= pBox->x2 || pBox->y1 >= pBox->y2)
+		continue;
+
+	    rowbytes = (pBox->x2 - pBox->x1) * cpp;
+	    src = (CARD8 *) pPixmap->devPrivate.ptr + pBox->y1 * src_pitch + pBox->x1 * cpp;
+	    dst = pExaPixmap->sys_ptr + pBox->y1 * dst_pitch + pBox->x1 * cpp;
+
+	    for (y = pBox->y1; y < pBox->y2;
+		 y++, src += src_pitch, dst += dst_pitch) {
+		if (memcmp(dst, src, rowbytes) != 0) {
+		    ret = FALSE;
+		    exaPixmapDirty(pPixmap, pBox->x1, pBox->y1, pBox->x2,
+				   pBox->y2);
+		    break;
+		}
+	    }
+    }
+
+skip:
+    exaFinishAccess(&pPixmap->drawable, EXA_PREPARE_SRC);
+
+    pExaPixmap->use_gpu_copy = save_use_gpu_copy;
+    pPixmap->devKind = save_pitch;
+
+out:
+    RegionUninit(&ValidReg);
+    return ret;
+}
+
+/**
+ * Performs migration of the pixmaps according to the operation information
+ * provided in pixmaps and can_accel and the migration scheme chosen in the
+ * config file.
+ */
+void
+exaDoMigration_classic (ExaMigrationPtr pixmaps, int npixmaps, Bool can_accel)
+{
+    ScreenPtr pScreen = pixmaps[0].pPix->drawable.pScreen;
+    ExaScreenPriv(pScreen);
+    int i, j;
+
+    /* If this debugging flag is set, check each pixmap for whether it is marked
+     * as clean, and if so, actually check if that's the case.  This should help
+     * catch issues with failing to mark a drawable as dirty.  While it will
+     * catch them late (after the operation happened), it at least explains what
+     * went wrong, and instrumenting the code to find what operation happened
+     * to the pixmap last shouldn't be hard.
+     */
+    if (pExaScr->checkDirtyCorrectness) {
+	for (i = 0; i < npixmaps; i++) {
+	    if (!exaPixmapIsDirty (pixmaps[i].pPix) &&
+		!exaAssertNotDirty (pixmaps[i].pPix))
+		ErrorF("%s: Pixmap %d dirty but not marked as such!\n", __func__, i);
+	}
+    }
+    /* If anything is pinned in system memory, we won't be able to
+     * accelerate.
+     */
+    for (i = 0; i < npixmaps; i++) {
+	if (exaPixmapIsPinned (pixmaps[i].pPix) &&
+	    !exaPixmapHasGpuCopy (pixmaps[i].pPix))
+	{
+	    EXA_FALLBACK(("Pixmap %p (%dx%d) pinned in sys\n", pixmaps[i].pPix,
+		      pixmaps[i].pPix->drawable.width,
+		      pixmaps[i].pPix->drawable.height));
+	    can_accel = FALSE;
+	    break;
+	}
+    }
+
+    if (pExaScr->migration == ExaMigrationSmart) {
+	/* If we've got something as a destination that we shouldn't cause to
+	 * become newly dirtied, take the unaccelerated route.
+	 */
+	for (i = 0; i < npixmaps; i++) {
+	    if (pixmaps[i].as_dst && !exaPixmapShouldBeInFB (pixmaps[i].pPix) &&
+		!exaPixmapIsDirty (pixmaps[i].pPix))
+	    {
+		for (i = 0; i < npixmaps; i++) {
+		    if (!exaPixmapIsDirty (pixmaps[i].pPix))
+			exaDoMoveOutPixmap (pixmaps + i);
+		}
+		return;
+	    }
+	}
+
+	/* If we aren't going to accelerate, then we migrate everybody toward
+	 * system memory, and kick out if it's free.
+	 */
+	if (!can_accel) {
+	    for (i = 0; i < npixmaps; i++) {
+		exaMigrateTowardSys (pixmaps + i);
+		if (!exaPixmapIsDirty (pixmaps[i].pPix))
+		    exaDoMoveOutPixmap (pixmaps + i);
+	    }
+	    return;
+	}
+
+	/* Finally, the acceleration path.  Move them all in. */
+	for (i = 0; i < npixmaps; i++) {
+	    exaMigrateTowardFb(pixmaps + i);
+	    exaDoMoveInPixmap(pixmaps + i);
+	}
+    } else if (pExaScr->migration == ExaMigrationGreedy) {
+	/* If we can't accelerate, either because the driver can't or because one of
+	 * the pixmaps is pinned in system memory, then we migrate everybody toward
+	 * system memory.
+	 *
+	 * We also migrate toward system if all pixmaps involved are currently in
+	 * system memory -- this can mitigate thrashing when there are significantly
+	 * more pixmaps active than would fit in memory.
+	 *
+	 * If not, then we migrate toward FB so that hopefully acceleration can
+	 * happen.
+	 */
+	if (!can_accel) {
+	    for (i = 0; i < npixmaps; i++)
+		exaMigrateTowardSys (pixmaps + i);
+	    return;
+	}
+
+	for (i = 0; i < npixmaps; i++) {
+	    if (exaPixmapHasGpuCopy(pixmaps[i].pPix)) {
+		/* Found one in FB, so move all to FB. */
+		for (j = 0; j < npixmaps; j++)
+		    exaMigrateTowardFb(pixmaps + i);
+		return;
+	    }
+	}
+
+	/* Nobody's in FB, so move all away from FB. */
+	for (i = 0; i < npixmaps; i++)
+	    exaMigrateTowardSys(pixmaps + i);
+    } else if (pExaScr->migration == ExaMigrationAlways) {
+	/* Always move the pixmaps out if we can't accelerate.  If we can
+	 * accelerate, try to move them all in.  If that fails, then move them
+	 * back out.
+	 */
+	if (!can_accel) {
+	    for (i = 0; i < npixmaps; i++)
+		exaDoMoveOutPixmap(pixmaps + i);
+	    return;
+	}
+
+	/* Now, try to move them all into FB */
+	for (i = 0; i < npixmaps; i++) {
+	    exaDoMoveInPixmap(pixmaps + i);
+	}
+
+	/* If we couldn't fit everything in, abort */
+	for (i = 0; i < npixmaps; i++) {
+	    if (!exaPixmapHasGpuCopy(pixmaps[i].pPix)) {
+		return;
+	    }
+	}
+
+	/* Yay, everything has a gpu copy, mark memory as used */
+	for (i = 0; i < npixmaps; i++) {
+	    ExaOffscreenMarkUsed (pixmaps[i].pPix);
+	}
+    }
+}
+
+void
+exaPrepareAccessReg_classic(PixmapPtr pPixmap, int index, RegionPtr pReg)
+{
+    ExaMigrationRec pixmaps[1];
+
+    if (index == EXA_PREPARE_DEST || index == EXA_PREPARE_AUX_DEST) {
+	pixmaps[0].as_dst = TRUE;
+	pixmaps[0].as_src = FALSE;
+    } else {
+	pixmaps[0].as_dst = FALSE;
+	pixmaps[0].as_src = TRUE;
+    }
+    pixmaps[0].pPix = pPixmap;
+    pixmaps[0].pReg = pReg;
+
+    exaDoMigration(pixmaps, 1, FALSE);
+
+    (void)ExaDoPrepareAccess(pPixmap, index);
+}