--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/cs/drivers/drv_app/ffs/board/reclaim.c	Sun Sep 25 22:50:11 2016 +0000
@@ -0,0 +1,883 @@
+/******************************************************************************
+ * Flash File System (ffs)
+ * Idea, design and coding by Mads Meisner-Jensen, mmj@ti.com
+ *
+ * FFS core reclaim functionality
+ *
+ * $Id: reclaim.c 1.4.1.28 Thu, 08 Jan 2004 15:05:23 +0100 tsj $
+ *
+ ******************************************************************************/
+
+#ifndef TARGET
+#include "ffs.cfg"
+#endif
+
+#include "ffs/ffs.h"
+#include "ffs/board/core.h"
+#include "ffs/board/drv.h"
+#include "ffs/board/ffstrace.h"
+
+#include <stdlib.h>  // rand()
+
+/******************************************************************************
+ * Inodes Reclaim
+ ******************************************************************************/
+
+void inodes_recurse(iref_t i)
+{
+    iref_t pi;
+    struct inode_s *ip, *newip;
+
+    tw(tr(TR_BEGIN, TrReclaimLow, "inodes_recurse(%d) {\n", i));
+
+    ip    = inode_addr(i);
+    newip = (struct inode_s *) offset2addr(dev.binfo[fs.newinodes].offset) + i;
+    
+    // copy inode dir to new block, except child, sibling and copied
+    ffsdrv.write((uint32*) &newip->location, (uint32*) &ip->location, sizeof(location_t));
+    ffsdrv.write_halfword((uint16*) &newip->size,     ip->size);
+    ffsdrv_write_byte    (&newip->flags,    ip->flags);
+    ffsdrv.write_halfword((uint16*) &newip->sequence, ip->sequence);
+    ffsdrv.write_halfword((uint16*) &newip->updates,  ip->updates);
+    bstat[fs.newinodes].used++;
+
+    // if no children of this dir, we have no more work to do
+    if (ip->child == (iref_t) IREF_NULL) {
+        tw(tr(TR_END, TrReclaimLow, "}\n"));
+        return;
+    }
+
+    pi = -i;
+    i = ip->child;
+    ip = inode_addr(i);
+
+    do {
+        tw(tr(TR_FUNC, TrReclaimLow, "pi = %d, i = %d", pi, i));
+
+        tw(tr(TR_NULL, TrReclaimLow, ", size = %d, location = 0x%x", ip->size, 
+              ip->location));
+        
+        tw(tr(TR_NULL, TrReclaimLow, ", name_addr = 0x%x",
+              addr2name(offset2addr(location2offset(ip->location)))));
+        
+        if (is_object(ip, OT_SEGMENT)) 
+            tw(tr(TR_NULL, TrReclaimLow, ", (segment)\n"));
+        
+        else
+            tw(tr(TR_NULL, TrReclaimLow, ", '%s'\n",
+                  (ip->size ? addr2name(offset2addr(location2offset(ip->location)))
+                   : "(cleaned)")));
+
+        if (is_object_valid(ip))
+        {
+            if (is_object(ip, OT_DIR)) {
+                tw(tr(TR_NULL, TrReclaimLow, "recursing...\n", i));
+                inodes_recurse(i);
+            }
+            else {
+                tw(tr(TR_NULL, TrReclaimLow, "copying...\n"));
+                // copy inode to new block, except child, sibling and copied
+                newip = (struct inode_s *)
+                    offset2addr(dev.binfo[fs.newinodes].offset) + i;
+                ffsdrv.write((uint32*) &newip->location, (uint32*) &ip->location, sizeof(location_t));
+                ffsdrv.write_halfword((uint16*) &newip->size,     ip->size);
+                ffsdrv_write_byte    (&newip->flags,    ip->flags);
+                ffsdrv.write_halfword((uint16*) &newip->sequence, ip->sequence);
+                ffsdrv.write_halfword((uint16*) &newip->updates,  ip->updates);
+                bstat[fs.newinodes].used++;
+            }
+
+            tw(tr(TR_FUNC, TrReclaimLow, "Linking: %d->%d\n",pi, i));
+            // now write the child or sibling link of previous inode
+            newip = (struct inode_s *)
+                offset2addr(dev.binfo[fs.newinodes].offset);
+            if (pi > 0)
+                ffsdrv.write_halfword((uint16*) &(newip + pi)->sibling, i);
+            else
+                ffsdrv.write_halfword((uint16*) &(newip + (-pi))->child, i);
+            
+            pi = i; // save index of previous inode
+            
+            if (ip->child != (iref_t) IREF_NULL && is_object(ip, OT_FILE)) {
+                iref_t pis, is;
+                struct inode_s *ips;
+                pis = i;
+                ips = ip;
+
+                tw(tr(TR_FUNC, TrReclaimLow, "Follow segment head\n"));
+                // While child is valid
+                while ((is = ips->child) != (iref_t) IREF_NULL) {
+
+                    // Get child
+                    is = ips->child;
+                    ips = inode_addr(is);
+                    tw(tr(TR_FUNC, TrReclaimLow, "Child ok, got new child i = %d\n", is));
+                    // While object not is valid
+                    while (!is_object_valid(ips)) {
+                        tw(tr(TR_FUNC, TrReclaimLow, "pi = %d, i = %d c(cleaned)\n", pis, is));
+                        // If sibling are valid
+                        if (ips->sibling != (iref_t) IREF_NULL) {  
+                            // Get sibling
+                            is = ips->sibling;
+                            ips = inode_addr(is);
+                            tw(tr(TR_FUNC, TrReclaimLow, "Sibling ok, got new sibling i = %d\n", is));
+                        }
+                        else {
+                            tw(tr(TR_FUNC, TrReclaimLow, "Sibling = FF (%d)\n", ips->sibling));
+                            break;  // Nothing more todo, child and sibling = FF
+                        }
+                    }
+                    // If object is valid
+                    if (is_object_valid(ips)) {
+                        tw(tr(TR_NULL, TrReclaimLow, "copying...\n"));
+                        // copy inode to new block, except child, sibling and copied
+                        newip = (struct inode_s *)
+                            offset2addr(dev.binfo[fs.newinodes].offset) + is;
+                        ffsdrv.write((uint32*) &newip->location, (uint32*) &ips->location, sizeof(location_t));
+                        ffsdrv.write_halfword((uint16*) &newip->size,     ips->size);
+                        ffsdrv_write_byte    (&newip->flags,              ips->flags);
+                        ffsdrv.write_halfword((uint16*) &newip->sequence, ips->sequence);
+                        ffsdrv.write_halfword((uint16*) &newip->updates,  ips->updates);
+                        bstat[fs.newinodes].used++;
+                        
+                        tw(tr(TR_FUNC, TrReclaimLow, "Linking child: %d->%d\n",pis, is));
+                        // now write the child link of previous inode
+                        newip = (struct inode_s *)
+                            offset2addr(dev.binfo[fs.newinodes].offset);
+                        ffsdrv.write_halfword((uint16*) &(newip + (pis))->child, is);
+                        
+                        pis = is; // save index of previous inode   
+               
+                    }     
+                    else {
+                        tw(tr(TR_FUNC, TrReclaimLow, "Sibling = FF (%d, %d)\n", 
+                              ips->sibling, ips->child));
+                    }
+
+                }
+            }
+        }       
+        else {
+            tw(tr(TR_NULL, TrReclaimLow, "(ignoring)\n"));
+        }
+        i = ip->sibling;
+        ip = inode_addr(i);
+            
+    } while (i != (iref_t) IREF_NULL);
+    
+    tw(tr(TR_END, TrReclaimLow, "}\n"));
+}
+
+// Reclaim inodes, eg. move inodes to another block and erase old one.
+effs_t inodes_reclaim(void)
+{
+    tw(tr(TR_BEGIN, TrIReclaim, "inodes_reclaim() {\n"));
+    ttw(str(TTrRec, "irec{"));
+
+    if (fs.initerror != EFFS_OK) {
+        tw(tr(TR_END, TrIReclaim, "} %d\n", fs.initerror));
+        ttw(ttr(TTrRec, "} %d" NL, fs.initerror));
+        return fs.initerror;
+    }
+
+    if ((fs.newinodes = block_alloc(1, BF_COPYING)) < 0) {
+        tw(tr(TR_END, TrIReclaim, "} %d\n", EFFS_NOBLOCKS));
+        ttw(ttr(TTrRec, "} %d" NL, EFFS_NOBLOCKS));
+        return EFFS_NOBLOCKS;
+    }
+
+    statistics_update_irec(bstat[fs.inodes].used - bstat[fs.inodes].lost, 
+                           bstat[fs.inodes].lost);
+
+    // copy all inodes...
+    bstat[fs.newinodes].used = 0;
+    inodes_recurse(fs.root);
+
+    block_commit();
+
+    tw(tr(TR_END, TrIReclaim, "} 0\n"));
+    ttw(str(TTrRec, "} 0" NL));
+
+    return EFFS_OK;
+}
+
+#if (FFS_TEST == 0)
+#define BLOCK_COMMIT_TEST(testcase, text)
+#else
+#if (TARGET == 0)
+// NOTEME: We have compressed the macro code because it will NOT compile on
+// Unix otherwise. So until we find out why, we use this as a work-around.
+#define BLOCK_COMMIT_TEST(testcase, text) if (fs.testflags == testcase) { tw(tr(TR_FUNC, TrData, "} (" text ")\n")); return; }
+#else
+#define BLOCK_COMMIT_TEST(testcase, text) if (fs.testflags == testcase) { ttw(ttr(TTrData, "} (" text ")\n")); return; }
+#endif
+#endif
+
+// Inode -> Lost, Copying -> Inode, Lost -> Free
+void block_commit(void)
+{
+    int oldinodes = fs.inodes;
+
+    tw(tr(TR_BEGIN, TrIReclaim, "block_commit(%d -> %d) {\n", 
+       oldinodes, fs.newinodes));
+    ttw(ttr(TTrRec, "block_commit(%d -> %d) {\n" NL, 
+       oldinodes, fs.newinodes)); 
+
+    BLOCK_COMMIT_TEST(BLOCK_COMMIT_BEFORE, "Oops before commit");
+
+    block_flags_write(oldinodes, BF_LOST);
+ 
+    BLOCK_COMMIT_TEST(BLOCK_COMMIT_NO_VALID, "Oops no valid inode block");
+
+    // Validate new block as an inodes block
+    block_flags_write(fs.newinodes, BF_INODES);
+
+    bstat[fs.newinodes].lost = 0;
+    bstat[fs.newinodes].objects = 1;
+    inodes_set(fs.newinodes);
+
+    // Free old inodes block
+    block_free(oldinodes);
+
+    BLOCK_COMMIT_TEST(BLOCK_COMMIT_OLD_FREE, "Oops after freeing old block");
+
+    BLOCK_COMMIT_TEST(BLOCK_COMMIT_AFTER, "Oops after commit");
+
+    ttw(str(TTrRec, "} 0" NL));
+    tw(tr(TR_END, TrIReclaim, "}\n"));
+}
+
+
+/******************************************************************************
+ * Data Reclaim
+ ******************************************************************************/
+
+// Important note: We must NOT perform a data reclaim when we are in the
+// process of creating the journal file!
+
+// Reclaim a data block, eg. move files to other blocks and erase old one.
+// When the reclaim is done, we must completely delete the old inodes which
+// are pointing into the old data sector which is going to be erased now.
+iref_t data_reclaim(int space)
+{
+    iref_t error;
+
+    tw(tr(TR_BEGIN, TrDReclaim, "data_reclaim(%d) {\n", space));
+
+    if (fs.initerror != EFFS_OK) {
+        tw(tr(TR_END, TrDReclaim, "} %d\n", fs.initerror));
+        return fs.initerror;
+    }
+
+    error = data_reclaim_try(space);
+
+    tw(tr(TR_END, TrDReclaim, "} (data_reclaim) %d\n", error));
+
+    return error;
+}
+
+int dage_max_reached(int dage_blk, int agegain)
+{
+    int reclaim, early, log2, mask;
+
+    tw(tr(TR_BEGIN, TrDReclaim, "young(%d, %d) {\n", dage_blk, agegain));
+    
+    // Simple algorithm
+    reclaim = (dage_blk + agegain - 2 * FFS_DAGE_MAX >= 0);
+
+    // Early exponential probability based reclaim
+    early = FFS_DAGE_MAX - dage_blk;
+    if (agegain > dage_blk - 4 && 0 < early && early <= FFS_DAGE_EARLY_WIDTH) {
+        if (early < 4)
+            early = 2;
+        if (early < FFS_DAGE_EARLY_WIDTH) {
+            // Now make an exponential probability distributon by
+            // generating a bitmask of a size relative to (dage_blk
+            // - DAGE_EARLY_WIDTH)
+            log2 = -1;
+            while (early > 0) {
+                early >>= 1;
+                log2++;
+            }
+            reclaim = log2;
+            
+            mask = (1 << (log2 + 1)) - 1;
+            reclaim = ((rand() & mask) == 0);
+        }
+    }
+
+    // Do not perform a reclaim unless we gain a certain minimum
+    if (agegain < FFS_DAGE_GAIN_MIN)
+        reclaim = 0;
+
+    tw(tr(TR_END, TrDReclaim, "} (%d)\n", reclaim));
+    return reclaim;
+}
+
+
+// Try to reclaim at least <space> bytes of data space. On success, return
+// the number of bytes actually reclaimed. Otherwise, on failure, return a
+// (negative) error.
+int data_reclaim_try(int space)
+{
+    // 1. Find a suitable block to reclaim.
+    //
+    // 2. Relocate each valid object from old block (to another block). An
+    // object relocation is similar to a normal file update, e.g. similar to
+    // fupdate().
+    //
+    // 3. If there is not enough space to relocate a file, we must alloc a
+    // new block then data_format() it.
+    //
+    // 4. set BF_CLEANING flag of old block.
+    //
+    // 5. ALL inodes (also invalid an erased ones) referring into reclaimed
+    // block must now be totally wiped out.
+    //
+    // 6. Free (invalidate) old block.
+
+    int result = 0, reserved_ok = 0;
+    bref_t b, blocks_free;
+    bref_t brc_young_b, brc_lost_b, brc_unused_b;
+
+    blocksize_t brc_lost_lost,   brc_lost_unused;
+    blocksize_t brc_unused_unused;
+    blocksize_t unused, unused_total, lost, lost_total, free;
+
+    age_t brc_young_dage, free_dage, dage;
+    struct block_header_s *bhp;
+    // Note gain can be negative if the free block is younger than the youngest data block
+    int age_gain; 
+
+    tw(tr(TR_BEGIN, TrDReclaim, "data_reclaim_try(%d) {\n", space));
+    ttw(str(TTrRec, "drec{" NL));
+
+    // While searching for a block to reclaim, we maintain three block
+    // reclaim candidates (brc): One with the maximum number of lost bytes,
+    // one with the maximum number of unused bytes and another for the
+    // youngest block, e.g. the one with the largest age distance to
+    // fs.age_max. The candidates are tried in the order mentioned.
+    
+    // This counts free blocks, so we initialize to number of blocks minus
+    // one for inodes.
+    blocks_free = dev.numblocks - 1;
+
+    // Initialize Block Reclaim Candidate (brc) variables
+    brc_lost_b   = -1; brc_lost_unused   = 0; brc_lost_lost   = 0;
+    brc_unused_b = -1; brc_unused_unused = 0; 
+
+    brc_young_b  = -1; brc_young_dage = 0;  free_dage  = 0;
+
+    lost_total   = 0;
+    unused_total = 0;
+
+    tw(tr(TR_FUNC, TrDReclaim,
+          "blk  unused    lost  w/age   age dist  objs\n"));
+    for (b = 0; b < dev.numblocks; b++)
+    {
+        bhp = (struct block_header_s *) offset2addr(dev.binfo[b].offset);
+
+        if (is_block(b, BF_IS_DATA))
+        {
+            // Record number of lost bytes and number of unused bytes,
+            // eg. total space that would be freed if this block was
+            // reclaimed
+            lost   = bstat[b].lost;
+            unused = dev.blocksize - (bstat[b].used - bstat[b].lost);
+            free   = dev.blocksize - bstat[b].used;
+
+            lost_total   += lost;
+            unused_total += unused;
+
+            if (free >= RESERVED_LOW) 
+                reserved_ok = 1;
+            if (lost > brc_lost_lost) {
+                brc_lost_b = b;
+                brc_lost_lost = lost;
+                brc_lost_unused = unused;
+            }
+            if (unused > brc_unused_unused) {
+                brc_unused_b = b;
+                brc_unused_unused = unused;
+            }
+
+            tw(tr(TR_FUNC, TrDReclaim, "%3d %7d %7d ", b, unused, lost));
+
+            dage = saturate_dage(fs.age_max - bhp->age);
+
+            tw(tr(TR_NULL, TrDReclaim, "%6d %5d %4d   %3d\n",
+                  lost, bhp->age, dage, bstat[b].objects));
+
+            if (dage >= brc_young_dage) {
+                brc_young_b = b;
+                brc_young_dage = dage;
+            }
+            blocks_free--;
+        }
+        else if (is_block(b, BF_IS_FREE)) {
+            unused_total += dev.blocksize;
+
+            // Find youngest free block (in must cases we will only have one free b)
+            dage = saturate_dage(fs.age_max - bhp->age);
+
+            if (dage >= free_dage)
+                free_dage = dage;   // Delta age of youngest free block
+        }
+    }
+    tw(tr(TR_FUNC, TrDReclaim, "sum %7d %7d\n", unused_total, lost_total));
+    tw(tr(TR_FUNC, TrDReclaim, "blocks_free = %d, fs.age_max = %d\n", blocks_free, fs.age_max));
+
+    age_gain = brc_young_dage - free_dage; // Same as free - block age
+  
+    if (space > unused_total) {
+        // We will never be able to reclaim this amount...
+        result = 0;
+    }
+    else {
+        // No additional blocks (apart from spare block) are free...
+        tw(tr(TR_FUNC, TrDReclaim,
+              "brc_young_dage = %d, brc_lost_unused = %d, brc_unused_unused = %d\n",
+              brc_young_dage, brc_lost_unused, brc_unused_unused));
+    
+        if (reserved_ok == 0) {
+            tw(tr(TR_FUNC, TrDReclaim, 
+                  "No reserved, reclaim most-lost block (%d)\n", brc_unused_b));
+            result = data_block_reclaim(brc_lost_b, MOST_LOST);
+        }
+        else if (dage_max_reached(brc_young_dage, age_gain) > 0 ) {
+            tw(tr(TR_FUNC, TrDReclaim, "Reclaiming youngest block (%d)\n",
+                  brc_young_b));
+            result = data_block_reclaim(brc_young_b, YOUNGEST);
+        }
+        else if (brc_lost_unused >= space) {
+            tw(tr(TR_FUNC, TrDReclaim, "Reclaiming most-lost block (%d)\n",
+                  brc_lost_b));
+            result = data_block_reclaim(brc_lost_b, MOST_LOST);
+        }
+        else if (brc_unused_unused >= space) {
+            tw(tr(TR_FUNC, TrDReclaim, "Reclaiming most-unused block (%d)\n",
+                  brc_unused_b));
+            result = data_block_reclaim(brc_unused_b, MOST_UNUSED);
+        }
+        else {
+            tw(tr(TR_FUNC, TrDReclaim, "Reclaiming most-lost blockx (%d)\n",
+                  brc_lost_b));
+            result = data_block_reclaim(brc_lost_b, MOST_LOST);
+            if (result >= 0)
+                result = 0;  // We reclaimed a block but we still need more space
+        }
+
+    }
+    tw(tr(TR_END, TrDReclaim, "} (data_reclaim_try) %d\n", result));
+
+    return result;
+}
+
+
+#if (FFS_TEST == 0)
+#define BLOCK_RECLAIM_TEST(testcase, text)
+#else
+#if (TARGET == 0)
+// NOTEME: We have compressed the macro code because it will NOT compile on
+// Unix otherwise. So until we find out why, we use this as a work-around.
+#define BLOCK_RECLAIM_TEST(testcase, text) if (fs.testflags == testcase) { tw(tr(TR_FUNC, TrTestHigh, "(" text ")\n")); tw(tr(TR_END, TrDReclaim, "} (Test) -100\n", result));return -100; }
+#else
+#define BLOCK_RECLAIM_TEST(testcase, text) if (fs.testflags == testcase) { ttw(ttr(TTrData, "} (" text ")"NL)); ttw(ttr(TTrRec, "} (Test) -100" NL));return -100; }
+#endif
+#endif
+
+#if (FFS_TEST == 0)
+#define BLOCK_RECOVER_TEST_INIT(testcase, text)
+#define BLOCK_RECOVER_TEST(testcase, text)
+#else
+#if (TARGET == 0)
+#define BLOCK_RECOVER_TEST_INIT(testcase, text) int rand_object; if (fs.testflags == testcase) { rand_object = rand() % bstat[b].objects; tw(tr(TR_FUNC, TrTestHigh, "Fail when object nr %d is relocated\n", rand_object)); }
+
+#define BLOCK_RECOVER_TEST(testcase, text) if (fs.testflags == testcase) {if (rand_object == n) { tw(tr(TR_FUNC, TrTestHigh, "(" text ")\n")); tw(tr(TR_END, TrDReclaim, "} (Test) -101\n", result)); return -101; } }
+
+#else   
+#define BLOCK_RECOVER_TEST_INIT(testcase, text) int rand_object; if (fs.testflags == testcase) { rand_object = rand() % bstat[b].objects; ttw(ttr(TTrData, "Fail when object nr %d is relocated" NL, rand_object)); }
+#define BLOCK_RECOVER_TEST(testcase, text) if (fs.testflags == testcase) {if (rand_object == n) { ttw(ttr(TTrData, "(" text ")" NL)); ttw(ttr(TTrRec, "} (Test) -101" NL, result)); return -101; } }
+#endif
+#endif
+
+iref_t data_block_reclaim(bref_t b, int candidate)
+{
+    iref_t i, n, j;
+    blocksize_t used_old, lost_old;
+	int org_res_space, result = 0;
+	iref_t org_block_files_reserved;
+    offset_t lower, upper;
+    struct inode_s *ip;
+	static int is_reclaim_running = 0;
+
+    tw(tr(TR_BEGIN, TrDReclaim, "data_block_reclaim(%d) {\n", b));
+
+    // In case of no free blocks (after sudden power off) or if the file
+    // system is near full we risk to be reentered (infinity recursively
+    // loop) and we can not allow that, so just return.
+	if (is_reclaim_running == 1) {
+		tw(tr(TR_END, TrDReclaim, "} (reenteret skip reclaim) 0\n"));
+		return EFFS_RECLAIMLOOP;
+	}
+
+	is_reclaim_running = 1;
+
+    // If there are more objects in this block than there are remaining
+    // free inodes, we have to make an inodes_reclaim() first.
+    tw(tr(TR_FUNC, TrDReclaim,
+          "block_objects, fs.inodes_max, inodes: used, free\n"));
+    tw(tr(TR_FUNC, TrDReclaim,
+          "%10d, %13d, %15d, %4d\n",
+          bstat[b].objects,
+          fs.inodes_max, bstat[fs.inodes].used,
+          fs.inodes_max - (bstat[fs.inodes].used + bstat[fs.inodes].lost)));
+
+    if (bstat[b].objects >= (fs.inodes_max - (bstat[fs.inodes].used + 
+                                              bstat[fs.inodes].lost + 
+                                              FFS_INODES_MARGIN))) {
+        tw(tr(TR_FUNC, TrInode, "NOTE: Will run out of free inodes...\n"));
+        inodes_reclaim();
+    }
+
+    // Allocate a new block. NOTE: we don't return an error because if we
+	// get in the situation where we don't have any free blocks this is the
+	// only way to recover.
+    if ((result = block_alloc(1, BF_DATA)) < 0) {
+        tw(tr(TR_FUNC, TrAll, "WARNING: block_alloc failed\n"));
+    }
+
+	BLOCK_RECLAIM_TEST(BLOCK_RECLAIM_ALLOC, "Oops after ffs_block_alloc()");
+
+    // If there are any objects at all to reclaim...
+    if (bstat[b].objects > 0)
+    {
+		BLOCK_RECOVER_TEST_INIT(BLOCK_RECOVER_OBJECTS, "Dummy")
+            // Save the current journal state
+            if (journal_push() != EFFS_OK) {
+                is_reclaim_running = 0;       // NOTEME: change to goto?
+                return EFFS_CORRUPTED;
+            }
+
+        // We simulate that this block is completely full, such that we
+        // don't relocate files to the end of the block
+        used_old = bstat[b].used;
+        lost_old = bstat[b].lost;  // For statistics
+        bstat[b].used = dev.blocksize - 1;
+
+
+        // Compute lower (inclusive) and upper (exclusive) bounds of the
+        // location of files in this block
+        lower = offset2location(dev.binfo[b].offset);
+        upper = offset2location(dev.binfo[b].offset + dev.blocksize);
+
+        tw(tr(TR_FUNC, TrDReclaim, "Block addr range = 0x%X..0x%X\n",
+              location2offset(lower), location2offset(upper)));
+
+		// This is the only time we are allowed to use the reserved 
+		org_block_files_reserved= fs.block_files_reserved;
+		fs.block_files_reserved = 0;
+
+		org_res_space = fs.reserved_space;
+        fs.reserved_space = RESERVED_NONE;
+
+		ip = inode_addr(1);
+        for (i = 1, n = 0; i < fs.inodes_max; i++, ip++)
+        {
+			BLOCK_RECOVER_TEST(BLOCK_RECOVER_OBJECTS, "Oops before relocate all objects");
+            // Ensure object is valid and within the block to be reclaimed
+            if (is_object_valid(ip) &&
+                lower <= ip->location && ip->location < upper)
+            {
+                if ((result = object_relocate(i)) < 0) {
+                    tw(tr(TR_FUNC, TrAll, "FATAL object_relocate failed\n"));
+                    break;
+                }
+                
+                // If we reclaim a segment head or wch that is in use we must
+                // update the file descriptor as well
+                for (j = 0; j < fs.fd_max; j++) {
+                    if (i == fs.fd[j].seghead) {
+                        tw(tr(TR_FUNC, TrDReclaim, 
+                              "Updated seghead %d -> %d \n",
+                              fs.fd[j].seghead, result));
+                        fs.fd[j].seghead = result;
+                    }
+                    if (i == fs.fd[j].wch) {
+                        tw(tr(TR_FUNC, TrDReclaim, 
+                              "Updated wch %d -> %d \n",
+                              fs.fd[j].wch, result));
+                        fs.fd[j].wch = result;
+                    }
+                }
+
+                // If we have just reclaimed an object which we started on
+                // updating we must also update ojournal
+                if (i == fs.ojournal.oldi) {
+                    struct inode_s *ip = inode_addr(result);
+                    tw(tr(TR_FUNC, TrDReclaim, 
+                          "Updated ojournal oldi %d -> %d \n",
+                          fs.ojournal.oldi, result));
+                    fs.ojournal.oldi     = result;
+                    fs.ojournal.location = ip->location;
+                }
+
+                if (i == fs.ojournal.diri || i == -fs.ojournal.diri) {
+                    fs.ojournal.diri = (fs.ojournal.diri < 0 ? -result : result);
+                    tw(tr(TR_FUNC, TrDReclaim, 
+                          "Updated ojournal: diri %d -> %d \n", 
+                          i, fs.ojournal.diri));
+                }
+
+                if (i == fs.ojournal.repli || i == -fs.ojournal.repli) {
+                    fs.ojournal.repli = (fs.ojournal.repli < 0 ? -result : result);
+                    tw(tr(TR_FUNC, TrDReclaim, 
+                          "Updated ojournal: repli %d -> %d \n", 
+                          i, fs.ojournal.repli));
+                }
+ 
+                if (i == fs.i_backup || i == -fs.i_backup) {
+                    fs.i_backup = (fs.i_backup < 0 ? -result : result);
+                    tw(tr(TR_FUNC, TrDReclaim, 
+                          "Updated i_backup: %d -> %d \n", i, fs.i_backup));
+                }
+
+                n++;
+            }
+        }
+
+		fs.block_files_reserved = org_block_files_reserved; // Restore
+		fs.reserved_space = org_res_space;
+
+        tw(tr(TR_FUNC, TrDReclaim, "Reclaimed %d objects\n", n));
+        if (result >= 0)
+            result = n; // We return number of objects relocated
+
+        if (i < fs.inodes_max) {
+            // We did not finish, so restore the old bstat[].used of the block.
+            bstat[b].used = used_old;
+            tw(tr(TR_FUNC, TrAll,
+                  "WARNING: data_block_reclaim() not completed\n"));
+            result = EFFS_DBR;
+		}
+
+        // Restore the saved journal state
+        if (journal_pop() != EFFS_OK) {
+			is_reclaim_running = 0;       // NOTEME: change to goto?
+			return EFFS_CORRUPTED;
+		}
+    }
+	BLOCK_RECLAIM_TEST(BLOCK_RECLAIM_NO_CLEAN, "Oops before clean old data block");
+
+    if (result >= 0) {
+        // Clean the block (remove all inodes that refer to this block)
+        block_flags_write(b, BF_CLEANING);
+        block_clean(b);
+
+        statistics_update_drec(used_old - lost_old, lost_old, candidate); 
+    
+		BLOCK_RECLAIM_TEST(BLOCK_RECLAIM_CLEANING, "Oops before free old data block");
+
+        // Free the old block
+        block_free(b);
+    }
+
+	is_reclaim_running = 0;
+
+    tw(tr(TR_END, TrDReclaim, "} (data_block_reclaim) %d\n", result));
+    ttw(ttr(TTrRec, "} %d" NL, result));
+
+    return result;
+}
+
+// Relocate object represented by inode reference <i>. 
+iref_t object_relocate(iref_t oldi)
+{
+    iref_t newi;
+    struct inode_s *oldip;
+    char *olddata, *oldname;
+    int oldsize;
+
+    tw(tr(TR_BEGIN, TrReclaimLow, "object_relocate(%d) {\n", oldi));
+
+    journal_begin(oldi);
+
+    oldip = inode_addr(oldi);
+
+    oldsize = segment_datasize(oldip);
+    olddata = offset2addr(location2offset(oldip->location));
+    oldname = addr2name(olddata);
+    olddata = addr2data(olddata, oldip);
+    
+    if (is_object(oldip, OT_SEGMENT))     
+        newi = segment_create(olddata, oldsize, -oldi);   
+    else {
+        // root inode is a special case
+        if (*oldname == '/')
+            newi = object_create(oldname, olddata, oldsize, 0);
+        else 
+            newi = object_create(oldname, olddata, oldsize, oldi);
+    }
+
+    if (newi < 0) {
+        tw(tr(TR_END, TrReclaimLow, "} %d\n", newi));
+        return newi;
+    }
+
+    // root inode is a special case
+    if ((*oldname == '/') && !is_object(oldip, OT_SEGMENT)) {
+        tw(tr(TR_FUNC, TrDReclaim, "Relocating fs.root: %d->%d\n", oldi, newi));
+        fs.root = newi;
+    }
+
+    journal_end(0);
+
+    tw(tr(TR_END, TrReclaimLow, "} %d\n", newi));
+
+    return newi;
+}
+
+// Clean a block, eg. erase all inodes that refer to this block.
+iref_t block_clean(bref_t b)
+{
+    iref_t i, n;
+    struct inode_s *ip;
+    offset_t lower, upper;
+
+    tw(tr(TR_FUNC, TrDReclaim, "block_clean(%d) { ", b));
+
+    // Compute lower (inclusive) and upper (exclusive) bounds of the
+    // location of files in this block
+    lower = offset2location(dev.binfo[b].offset);
+    upper = offset2location(dev.binfo[b].offset + dev.blocksize);
+
+    tw(tr(TR_FUNC, TrDReclaim, "offset range = 0x%X..0x%X: ", lower, upper));
+
+    ip = inode_addr(1);
+    for (i = 1, n = 0; i < fs.inodes_max; i++, ip++)
+    {
+        // Ensure object is within the block to be reclaimed. Note: if ffs
+        // is conf. with 1MB or above will all not used inodes default have
+        // the location to FFFF which will trigger a clean and make a error!
+        if (lower <= ip->location && upper > ip->location)
+        {
+            tw(tr(TR_NULL, TrReclaimLow, "%d ", i));
+            // Set the size to zero so it won't be counted in ffs_initialize()
+            ffsdrv.write_halfword((uint16 *) &ip->size, 0);
+            n++;
+        }
+    }
+    tw(tr(TR_NULL, TrDReclaim, "} %d\n", n));
+
+    return n;
+}
+
+
+/******************************************************************************
+ * Main and block reclaim
+ ******************************************************************************/
+
+// Reclaim (erase) all blocks that are marked as invalid/reclaimable. Each
+// time a block is erased, its age is incremented so as to support wear
+// levelling. Also, the global age limits are updated.  FIXME: Should we
+// avoid having ffs_initialize() do a block_reclaim() because it delays reboot?.
+int blocks_reclaim(void)
+{
+    bref_t b, n, b_lost_space;
+	int blocks_free = 0, lost_space;
+
+	int free_space, b_free_space;
+
+    tw(tr(TR_BEGIN, TrBlock, "blocks_reclaim() {\n"));
+    ttw(str(TTrRec, "blocks_reclaim() {" NL));
+
+    // Testing of fs.testflags is for the sake of testing block_commit()
+    if ((fs.testflags & BLOCK_COMMIT_BASE) != 0) {
+        tw(tr(TR_FUNC, TrBlock, "Bailing out because fs.testflags = 0x%X\n",
+              fs.testflags));
+    }
+    else {
+        for (b = 0, n = 0; b < dev.numblocks; b++) {
+            if (is_block_flag(b, BF_LOST)) {
+                block_reclaim(b);
+                n++;
+            }
+			if (is_block(b, BF_IS_FREE)) {
+				blocks_free++;
+			}
+        }
+    }
+
+	// If the number of free blocks is less than fs.blocks_free_min we
+	// call data_block_reclaim(). We will reclaim the block with most lost
+	// space. This should only happend if we got a sudden power off/reset
+	// while we reclaimed a block.
+	if (blocks_free < fs.blocks_free_min) {
+		lost_space = 0;
+		free_space = 0;
+
+		// We most never reclaim the block with most free space because this
+		// is the only block we can relocate the objects to.
+		for (b = 0; b < dev.numblocks; b++) {
+			if (is_block_flag(b, BF_DATA)) {
+				if ((dev.blocksize - bstat[b].used) > free_space) {
+					free_space = dev.blocksize - bstat[b].used;
+					b_free_space = b;
+				}
+			}
+		}
+		tw(tr(TR_FUNC, TrBlock, "most free space: %d in block: %d \n", 
+			  free_space, b_free_space));
+
+		for (b = 0; b < dev.numblocks; b++) {
+			if (is_block_flag(b, BF_DATA) && b != b_free_space) {
+				if (bstat[b].lost > lost_space) {
+					lost_space = bstat[b].lost;
+					b_lost_space = b;
+				}
+			}
+		}
+		tw(tr(TR_FUNC, TrBlock, "most lost space: %d in block: %d \n", 
+			  lost_space, b_lost_space));
+
+		data_block_reclaim(b_lost_space, MOST_LOST);
+	}
+    tw(tr(TR_END, TrBlock, "} %d\n", n));
+    ttw(ttr(TTrRec, "} %d" NL, n));
+
+    return n;
+}
+
+int block_reclaim(bref_t b)
+{
+    age_t age;
+    struct block_header_s *bhp;
+
+    tw(tr(TR_BEGIN, TrBlock, "block_reclaim(%d) {\n", b));
+
+    // In ffs_initialize() we set fs.initerror = EFFS_INVALID while we call
+    // blocks_fsck(). We test for that condition now, in order to avoid
+    // doing sector erases that will delay the whole target boot process.
+    if (fs.initerror == EFFS_INVALID) {
+        tw(tr(TR_END, TrBlock, "} %d\n", fs.initerror));
+        return fs.initerror;
+    }
+
+    // Testing of fs.testflags is for the sake of testing block_commit()
+    if ((fs.testflags & BLOCK_COMMIT_BASE) != 0 && 
+		fs.testflags != BLOCK_COMMIT_OLD_FREE) {
+        tw(tr(TR_FUNC, TrBlock, "Bailing out because fs.testflags = 0x%X\n",
+              fs.testflags));
+    }
+    else {
+        // We must read block's age before we erase it.
+        bhp = (struct block_header_s *) offset2addr(dev.binfo[b].offset);
+        age = bhp->age;
+        ffsdrv.erase(b);
+        block_preformat(b, age);
+    }
+
+    tw(tr(TR_END, TrBlock, "} %d\n", 0));
+
+    return 0;
+}