Changeset d044447 in mainline

Timestamp:

2009-09-03T15:58:28Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

029d94a

Parents:

056fa40 (diff), 2f636b6 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge FAT server error handling improvements.

Location:

uspace/srv/fs/fat

Files:

• fat_fat.c (modified) (23 diffs)
• fat_fat.h (modified) (1 diff)
• fat_ops.c (modified) (21 diffs)

uspace/srv/fs/fat/fat_fat.c

@@ -61 +61 @@
  * @param dev_handle    Device handle of the device with the file.
  * @param firstc        First cluster to start the walk with.
- * @param lastc         If non-NULL, output argument hodling the last cluster number visited.
+ * @param lastc         If non-NULL, output argument hodling the last cluster
+ *                      number visited.
+ * @param numc          If non-NULL, output argument holding the number of
+ *                      clusters seen during the walk.
  * @param max_clusters  Maximum number of clusters to visit.    
  *
- * @return              Number of clusters seen during the walk.
- */
-uint16_t 
+ * @return              EOK on success or a negative error code.
+ */
+int 
 fat_cluster_walk(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc,
-    fat_cluster_t *lastc, uint16_t max_clusters)
+    fat_cluster_t *lastc, uint16_t *numc, uint16_t max_clusters)
 {
         block_t *b;
@@ -84 +87 @@
                 if (lastc)
                         *lastc = firstc;
-                return 0;
+                if (numc)
+                        *numc = 0;
+                return EOK;
         }
 
@@ -98 +103 @@
                 /* read FAT1 */
                 rc = block_get(&b, dev_handle, rscnt + fsec, BLOCK_FLAGS_NONE);
-                assert(rc == EOK);
+                if (rc != EOK)
+                        return rc;
                 clst = uint16_t_le2host(((fat_cluster_t *)b->data)[fidx]);
                 assert(clst != FAT_CLST_BAD);
                 rc = block_put(b);
-                assert(rc == EOK);
+                if (rc != EOK)
+                        return rc;
                 clusters++;
         }
@@ -108 +115 @@
         if (lastc && clst < FAT_CLST_LAST1)
                 *lastc = clst;
-
-        return clusters;
+        if (numc)
+                *numc = clusters;
+
+        return EOK;
 }
 
 /** Read block from file located on a FAT file system.
  *
+ * @param block         Pointer to a block pointer for storing result.
  * @param bs            Buffer holding the boot sector of the file system.
  * @param dev_handle    Device handle of the file system.
@@ -121 +131 @@
  * @param flags         Flags passed to libblock.
  *
- * @return              Block structure holding the requested block.
- */
-block_t *
-_fat_block_get(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc,
-    bn_t bn, int flags)
-{
-        block_t *b;
+ * @return              EOK on success or a negative error code.
+ */
+int
+_fat_block_get(block_t **block, fat_bs_t *bs, dev_handle_t dev_handle,
+    fat_cluster_t firstc, bn_t bn, int flags)
+{
         unsigned bps;
         unsigned rscnt;         /* block address of the first FAT */
@@ -134 +143 @@
         unsigned sf;
         unsigned ssa;           /* size of the system area */
-        unsigned clusters, max_clusters;
+        uint16_t clusters;
+        unsigned max_clusters;
         fat_cluster_t lastc;
         int rc;
@@ -150 +160 @@
                 /* root directory special case */
                 assert(bn < rds);
-                rc = block_get(&b, dev_handle, rscnt + bs->fatcnt * sf + bn,
+                rc = block_get(block, dev_handle, rscnt + bs->fatcnt * sf + bn,
                     flags);
-                assert(rc == EOK);
-                return b;
+                return rc;
         }
 
         max_clusters = bn / bs->spc;
-        clusters = fat_cluster_walk(bs, dev_handle, firstc, &lastc,
+        rc = fat_cluster_walk(bs, dev_handle, firstc, &lastc, &clusters,
             max_clusters);
+        if (rc != EOK)
+                return rc;
         assert(clusters == max_clusters);
 
-        rc = block_get(&b, dev_handle, ssa +
-            (lastc - FAT_CLST_FIRST) * bs->spc + bn % bs->spc, flags);
-        assert(rc == EOK);
-
-        return b;
+        rc = block_get(block, dev_handle,
+            ssa + (lastc - FAT_CLST_FIRST) * bs->spc + bn % bs->spc, flags);
+
+        return rc;
 }
 
@@ -177 +187 @@
  *                      this argument is ignored.
  * @param pos           Position in the last node block.
- */
-void fat_fill_gap(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl, off_t pos)
+ *
+ * @return              EOK on success or a negative error code.
+ */
+int fat_fill_gap(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl, off_t pos)
 {
         uint16_t bps;
@@ -196 +208 @@
                 int flags = (o % bps == 0) ?
                     BLOCK_FLAGS_NOREAD : BLOCK_FLAGS_NONE;
-                b = fat_block_get(bs, nodep, o / bps, flags);
+                rc = fat_block_get(&b, bs, nodep, o / bps, flags);
+                if (rc != EOK)
+                        return rc;
                 memset(b->data + o % bps, 0, bps - o % bps);
                 b->dirty = true;                /* need to sync node */
                 rc = block_put(b);
-                assert(rc == EOK);
+                if (rc != EOK)
+                        return rc;
         }
         
         if (o >= pos)
-                return;
+                return EOK;
         
         /* zero out the initial part of the new cluster chain */
         for (o = boundary; o < pos; o += bps) {
-                b = _fat_block_get(bs, nodep->idx->dev_handle, mcl,
+                rc = _fat_block_get(&b, bs, nodep->idx->dev_handle, mcl,
                     (o - boundary) / bps, BLOCK_FLAGS_NOREAD);
+                if (rc != EOK)
+                        return rc;
                 memset(b->data, 0, min(bps, pos - o));
                 b->dirty = true;                /* need to sync node */
                 rc = block_put(b);
-                assert(rc == EOK);
-        }
+                if (rc != EOK)
+                        return rc;
+        }
+
+        return EOK;
 }
 
@@ -222 +242 @@
  * @param dev_handle    Device handle for the file system.
  * @param clst          Cluster which to get.
- *
- * @return              Value found in the cluster.
- */
-fat_cluster_t
-fat_get_cluster(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t clst)
+ * @param value         Output argument holding the value of the cluster.
+ *
+ * @return              EOK or a negative error code.
+ */
+int
+fat_get_cluster(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t clst,
+    fat_cluster_t *value)
 {
         block_t *b;
         uint16_t bps;
         uint16_t rscnt;
-        fat_cluster_t *cp, value;
+        fat_cluster_t *cp;
         int rc;
 
@@ -239 +261 @@
         rc = block_get(&b, dev_handle, rscnt +
             (clst * sizeof(fat_cluster_t)) / bps, BLOCK_FLAGS_NONE);
-        assert(rc == EOK);
+        if (rc != EOK)
+                return rc;
         cp = (fat_cluster_t *)b->data + clst % (bps / sizeof(fat_cluster_t));
-        value = uint16_t_le2host(*cp);
+        *value = uint16_t_le2host(*cp);
         rc = block_put(b);
-        assert(rc == EOK);
-        
-        return value;
+        
+        return rc;
 }
 
@@ -255 +277 @@
  * @param clst          Cluster which is to be set.
  * @param value         Value to set the cluster with.
- */
-void
+ *
+ * @return              EOK on success or a negative error code.
+ */
+int
 fat_set_cluster(fat_bs_t *bs, dev_handle_t dev_handle, unsigned fatno,
     fat_cluster_t clst, fat_cluster_t value)
@@ -274 +298 @@
         rc = block_get(&b, dev_handle, rscnt + sf * fatno +
             (clst * sizeof(fat_cluster_t)) / bps, BLOCK_FLAGS_NONE);
-        assert(rc == EOK);
+        if (rc != EOK)
+                return rc;
         cp = (fat_cluster_t *)b->data + clst % (bps / sizeof(fat_cluster_t));
         *cp = host2uint16_t_le(value);
         b->dirty = true;                /* need to sync block */
         rc = block_put(b);
-        assert(rc == EOK);
+        return rc;
 }
 
@@ -288 +313 @@
  * @param lifo          Chain of allocated clusters.
  * @param nclsts        Number of clusters in the lifo chain.
- */
-void fat_alloc_shadow_clusters(fat_bs_t *bs, dev_handle_t dev_handle,
+ *
+ * @return              EOK on success or a negative error code.
+ */
+int fat_alloc_shadow_clusters(fat_bs_t *bs, dev_handle_t dev_handle,
     fat_cluster_t *lifo, unsigned nclsts)
 {
         uint8_t fatno;
         unsigned c;
+        int rc;
 
         for (fatno = FAT1 + 1; fatno < bs->fatcnt; fatno++) {
                 for (c = 0; c < nclsts; c++) {
-                        fat_set_cluster(bs, dev_handle, fatno, lifo[c],
+                        rc = fat_set_cluster(bs, dev_handle, fatno, lifo[c],
                             c == 0 ? FAT_CLST_LAST1 : lifo[c - 1]);
+                        if (rc != EOK)
+                                return rc;
                 }
         }
+
+        return EOK;
 }
 
@@ -347 +379 @@
         for (b = 0, cl = 0; b < sf; b++) {
                 rc = block_get(&blk, dev_handle, rscnt + b, BLOCK_FLAGS_NONE);
+                if (rc != EOK)
+                        goto error;
                 for (c = 0; c < bps / sizeof(fat_cluster_t); c++, cl++) {
                         fat_cluster_t *clst = (fat_cluster_t *)blk->data + c;
@@ -362 +396 @@
                                         /* we are almost done */
                                         rc = block_put(blk);
-                                        assert(rc == EOK);
+                                        if (rc != EOK)
+                                                goto error;
                                         /* update the shadow copies of FAT */
-                                        fat_alloc_shadow_clusters(bs,
+                                        rc = fat_alloc_shadow_clusters(bs,
                                             dev_handle, lifo, nclsts);
+                                        if (rc != EOK)
+                                                goto error;
                                         *mcl = lifo[found - 1];
                                         *lcl = lifo[0];
@@ -375 +412 @@
                 }
                 rc = block_put(blk);
-                assert(rc == EOK);
+                if (rc != EOK) {
+error:
+                        fibril_mutex_unlock(&fat_alloc_lock);
+                        free(lifo);
+                        return rc;
+                }
         }
         fibril_mutex_unlock(&fat_alloc_lock);
@@ -384 +426 @@
          */
         while (found--) {
-                fat_set_cluster(bs, dev_handle, FAT1, lifo[found],
+                rc = fat_set_cluster(bs, dev_handle, FAT1, lifo[found],
                     FAT_CLST_RES0);
+                if (rc != EOK) {
+                        free(lifo);
+                        return rc;
+                }
         }
         
@@ -397 +443 @@
  * @param dev_handle    Device handle of the file system.
  * @param firstc        First cluster in the chain which is to be freed.
- */
-void
+ *
+ * @return              EOK on success or a negative return code.
+ */
+int
 fat_free_clusters(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc)
 {
         unsigned fatno;
         fat_cluster_t nextc;
+        int rc;
 
         /* Mark all clusters in the chain as free in all copies of FAT. */
         while (firstc < FAT_CLST_LAST1) {
                 assert(firstc >= FAT_CLST_FIRST && firstc < FAT_CLST_BAD);
-                nextc = fat_get_cluster(bs, dev_handle, firstc);
-                for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
-                        fat_set_cluster(bs, dev_handle, fatno, firstc,
+                rc = fat_get_cluster(bs, dev_handle, firstc, &nextc);
+                if (rc != EOK)
+                        return rc;
+                for (fatno = FAT1; fatno < bs->fatcnt; fatno++) {
+                        rc = fat_set_cluster(bs, dev_handle, fatno, firstc,
                             FAT_CLST_RES0);
+                        if (rc != EOK)
+                                return rc;
+                }
+
                 firstc = nextc;
         }
+
+        return EOK;
 }
 
@@ -420 +477 @@
  * @param nodep         Node representing the file.
  * @param mcl           First cluster of the cluster chain to append.
- */
-void fat_append_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl)
+ *
+ * @return              EOK on success or a negative error code.
+ */
+int fat_append_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t mcl)
 {
         dev_handle_t dev_handle = nodep->idx->dev_handle;
         fat_cluster_t lcl;
+        uint16_t numc;
         uint8_t fatno;
-
-        if (fat_cluster_walk(bs, dev_handle, nodep->firstc, &lcl,
-            (uint16_t) -1) == 0) {
+        int rc;
+
+        rc = fat_cluster_walk(bs, dev_handle, nodep->firstc, &lcl, &numc,
+            (uint16_t) -1);
+        if (rc != EOK)
+                return rc;
+
+        if (numc == 0) {
                 /* No clusters allocated to the node yet. */
                 nodep->firstc = mcl;
                 nodep->dirty = true;            /* need to sync node */
-                return;
-        }
-
-        for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
-                fat_set_cluster(bs, nodep->idx->dev_handle, fatno, lcl, mcl);
+                return EOK;
+        }
+
+        for (fatno = FAT1; fatno < bs->fatcnt; fatno++) {
+                rc = fat_set_cluster(bs, nodep->idx->dev_handle, fatno, lcl,
+                    mcl);
+                if (rc != EOK)
+                        return rc;
+        }
+
+        return EOK;
 }
 
@@ -446 +517 @@
  *                      argument is FAT_CLST_RES0, then all clusters will
  *                      be chopped off.
- */
-void fat_chop_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t lastc)
-{
+ *
+ * @return              EOK on success or a negative return code.
+ */
+int fat_chop_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t lastc)
+{
+        int rc;
+
         dev_handle_t dev_handle = nodep->idx->dev_handle;
         if (lastc == FAT_CLST_RES0) {
                 /* The node will have zero size and no clusters allocated. */
-                fat_free_clusters(bs, dev_handle, nodep->firstc);
+                rc = fat_free_clusters(bs, dev_handle, nodep->firstc);
+                if (rc != EOK)
+                        return rc;
                 nodep->firstc = FAT_CLST_RES0;
                 nodep->dirty = true;            /* need to sync node */
@@ -459 +536 @@
                 unsigned fatno;
 
-                nextc = fat_get_cluster(bs, dev_handle, lastc);
+                rc = fat_get_cluster(bs, dev_handle, lastc, &nextc);
+                if (rc != EOK)
+                        return rc;
 
                 /* Terminate the cluster chain in all copies of FAT. */
-                for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
-                        fat_set_cluster(bs, dev_handle, fatno, lastc, FAT_CLST_LAST1);
+                for (fatno = FAT1; fatno < bs->fatcnt; fatno++) {
+                        rc = fat_set_cluster(bs, dev_handle, fatno, lastc,
+                            FAT_CLST_LAST1);
+                        if (rc != EOK)
+                                return rc;
+                }
 
                 /* Free all following clusters. */
-                fat_free_clusters(bs, dev_handle, nextc);
-        }
-}
-
-void
+                rc = fat_free_clusters(bs, dev_handle, nextc);
+                if (rc != EOK)
+                        return rc;
+        }
+
+        return EOK;
+}
+
+int
 fat_zero_cluster(struct fat_bs *bs, dev_handle_t dev_handle, fat_cluster_t c)
 {
@@ -481 +568 @@
         
         for (i = 0; i < bs->spc; i++) {
-                b = _fat_block_get(bs, dev_handle, c, i, BLOCK_FLAGS_NOREAD);
+                rc = _fat_block_get(&b, bs, dev_handle, c, i,
+                    BLOCK_FLAGS_NOREAD);
+                if (rc != EOK)
+                        return rc;
                 memset(b->data, 0, bps);
                 b->dirty = true;
                 rc = block_put(b);
-                assert(rc == EOK);
-        }
+                if (rc != EOK)
+                        return rc;
+        }
+
+        return EOK;
 }
 

uspace/srv/fs/fat/fat_fat.h

@@ -59 +59 @@
 typedef uint16_t fat_cluster_t;
 
-#define fat_clusters_get(bs, dh, fc) \
-    fat_cluster_walk((bs), (dh), (fc), NULL, (uint16_t) -1)
-extern uint16_t fat_cluster_walk(struct fat_bs *, dev_handle_t, fat_cluster_t,
-    fat_cluster_t *, uint16_t);
+#define fat_clusters_get(numc, bs, dh, fc) \
+    fat_cluster_walk((bs), (dh), (fc), NULL, (numc), (uint16_t) -1)
+extern int fat_cluster_walk(struct fat_bs *, dev_handle_t, fat_cluster_t,
+    fat_cluster_t *, uint16_t *, uint16_t);
 
-#define fat_block_get(bs, np, bn, flags) \
-    _fat_block_get((bs), (np)->idx->dev_handle, (np)->firstc, (bn), (flags))
+#define fat_block_get(b, bs, np, bn, flags) \
+    _fat_block_get((b), (bs), (np)->idx->dev_handle, (np)->firstc, (bn), \
+    (flags))
 
-extern struct block *_fat_block_get(struct fat_bs *, dev_handle_t,
+extern int _fat_block_get(block_t **, struct fat_bs *, dev_handle_t,
     fat_cluster_t, bn_t, int);
   
-extern void fat_append_clusters(struct fat_bs *, struct fat_node *,
+extern int fat_append_clusters(struct fat_bs *, struct fat_node *,
     fat_cluster_t);
-extern void fat_chop_clusters(struct fat_bs *, struct fat_node *,
+extern int fat_chop_clusters(struct fat_bs *, struct fat_node *,
     fat_cluster_t);
 extern int fat_alloc_clusters(struct fat_bs *, dev_handle_t, unsigned,
     fat_cluster_t *, fat_cluster_t *);
-extern void fat_free_clusters(struct fat_bs *, dev_handle_t, fat_cluster_t);
-extern void fat_alloc_shadow_clusters(struct fat_bs *, dev_handle_t,
+extern int fat_free_clusters(struct fat_bs *, dev_handle_t, fat_cluster_t);
+extern int fat_alloc_shadow_clusters(struct fat_bs *, dev_handle_t,
     fat_cluster_t *, unsigned);
-extern fat_cluster_t fat_get_cluster(struct fat_bs *, dev_handle_t, fat_cluster_t);
-extern void fat_set_cluster(struct fat_bs *, dev_handle_t, unsigned,
+extern int fat_get_cluster(struct fat_bs *, dev_handle_t, fat_cluster_t,
+    fat_cluster_t *);
+extern int fat_set_cluster(struct fat_bs *, dev_handle_t, unsigned,
     fat_cluster_t, fat_cluster_t);
-extern void fat_fill_gap(struct fat_bs *, struct fat_node *, fat_cluster_t,
+extern int fat_fill_gap(struct fat_bs *, struct fat_node *, fat_cluster_t,
     off_t);
-extern void fat_zero_cluster(struct fat_bs *, dev_handle_t, fat_cluster_t);
+extern int fat_zero_cluster(struct fat_bs *, dev_handle_t, fat_cluster_t);
 
 #endif

uspace/srv/fs/fat/fat_ops.c

@@ -94 +94 @@
         
         /* Read the block that contains the dentry of interest. */
-        b = _fat_block_get(bs, node->idx->dev_handle, node->idx->pfc,
+        rc = _fat_block_get(&b, bs, node->idx->dev_handle, node->idx->pfc,
             (node->idx->pdi * sizeof(fat_dentry_t)) / bps, BLOCK_FLAGS_NONE);
+        assert(rc == EOK);
 
         d = ((fat_dentry_t *)b->data) + (node->idx->pdi % dps);
@@ -202 +203 @@
 
         /* Read the block that contains the dentry of interest. */
-        b = _fat_block_get(bs, idxp->dev_handle, idxp->pfc,
+        rc = _fat_block_get(&b, bs, idxp->dev_handle, idxp->pfc,
             (idxp->pdi * sizeof(fat_dentry_t)) / bps, BLOCK_FLAGS_NONE);
-        assert(b);
+        assert(rc == EOK);
 
         d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);
@@ -219 +220 @@
                  * size of the directory by walking the FAT.
                  */
-                nodep->size = bps * spc * fat_clusters_get(bs, idxp->dev_handle,
+                uint16_t clusters;
+                rc = fat_clusters_get(&clusters, bs, idxp->dev_handle,
                     uint16_t_le2host(d->firstc));
+                assert(rc == EOK);
+                nodep->size = bps * spc * clusters;
         } else {
                 nodep->type = FAT_FILE;
@@ -325 +329 @@
         nodep = fat_node_get_new();
         if (!nodep) {
-                fat_free_clusters(bs, dev_handle, mcl); 
+                (void) fat_free_clusters(bs, dev_handle, mcl);
                 return NULL;
         }
         idxp = fat_idx_get_new(dev_handle);
         if (!idxp) {
-                fat_free_clusters(bs, dev_handle, mcl); 
+                (void) fat_free_clusters(bs, dev_handle, mcl);  
                 fat_node_put(FS_NODE(nodep));
                 return NULL;
@@ -337 +341 @@
         if (flags & L_DIRECTORY) {
                 /* Populate the new cluster with unused dentries. */
-                fat_zero_cluster(bs, dev_handle, mcl);
+                rc = fat_zero_cluster(bs, dev_handle, mcl);
+                assert(rc == EOK);
                 nodep->type = FAT_DIRECTORY;
                 nodep->firstc = mcl;
@@ -361 +366 @@
         fat_node_t *nodep = FAT_NODE(fn);
         fat_bs_t *bs;
+        int rc = EOK;
 
         /*
@@ -379 +385 @@
                 assert(nodep->size);
                 /* Free all clusters allocated to the node. */
-                fat_free_clusters(bs, nodep->idx->dev_handle, nodep->firstc);
+                rc = fat_free_clusters(bs, nodep->idx->dev_handle,
+                    nodep->firstc);
         }
 
@@ -385 +392 @@
         free(nodep->bp);
         free(nodep);
-        return EOK;
+        return rc;
 }
 
@@ -433 +440 @@
 
         for (i = 0; i < blocks; i++) {
-                b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE);
+                rc = fat_block_get(&b, bs, parentp, i, BLOCK_FLAGS_NONE);
+                assert(rc == EOK);
                 for (j = 0; j < dps; j++) {
                         d = ((fat_dentry_t *)b->data) + j;
@@ -465 +473 @@
                 return rc;
         }
-        fat_zero_cluster(bs, parentp->idx->dev_handle, mcl);
-        fat_append_clusters(bs, parentp, mcl);
+        rc = fat_zero_cluster(bs, parentp->idx->dev_handle, mcl);
+        assert(rc == EOK);
+        rc = fat_append_clusters(bs, parentp, mcl);
+        assert(rc == EOK);
         parentp->size += bps * bs->spc;
         parentp->dirty = true;          /* need to sync node */
-        b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE);
+        rc = fat_block_get(&b, bs, parentp, i, BLOCK_FLAGS_NONE);
+        assert(rc == EOK);
         d = (fat_dentry_t *)b->data;
 
@@ -494 +505 @@
          * not use them anyway, so this is rather a sign of our good will.
          */
-        b = fat_block_get(bs, childp, 0, BLOCK_FLAGS_NONE);
+        rc = fat_block_get(&b, bs, childp, 0, BLOCK_FLAGS_NONE);
+        assert(rc == EOK);
         d = (fat_dentry_t *)b->data;
         if (fat_classify_dentry(d) == FAT_DENTRY_LAST ||
@@ -561 +573 @@
         bps = uint16_t_le2host(bs->bps);
 
-        b = _fat_block_get(bs, childp->idx->dev_handle, childp->idx->pfc,
+        rc = _fat_block_get(&b, bs, childp->idx->dev_handle, childp->idx->pfc,
             (childp->idx->pdi * sizeof(fat_dentry_t)) / bps,
             BLOCK_FLAGS_NONE);
+        assert(rc == EOK);
         d = (fat_dentry_t *)b->data +
             (childp->idx->pdi % (bps / sizeof(fat_dentry_t)));
@@ -605 +618 @@
         blocks = parentp->size / bps;
         for (i = 0; i < blocks; i++) {
-                b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE);
+                rc = fat_block_get(&b, bs, parentp, i, BLOCK_FLAGS_NONE);
+                assert(rc == EOK);
                 for (j = 0; j < dps; j++) { 
                         d = ((fat_dentry_t *)b->data) + j;
@@ -698 +712 @@
                 fat_dentry_t *d;
         
-                b = fat_block_get(bs, nodep, i, BLOCK_FLAGS_NONE);
+                rc = fat_block_get(&b, bs, nodep, i, BLOCK_FLAGS_NONE);
+                assert(rc == EOK);
                 for (j = 0; j < dps; j++) {
                         d = ((fat_dentry_t *)b->data) + j;
@@ -953 +968 @@
                         bytes = min(len, bps - pos % bps);
                         bytes = min(bytes, nodep->size - pos);
-                        b = fat_block_get(bs, nodep, pos / bps,
+                        rc = fat_block_get(&b, bs, nodep, pos / bps,
                             BLOCK_FLAGS_NONE);
+                        assert(rc == EOK);
                         (void) ipc_data_read_finalize(callid, b->data + pos % bps,
                             bytes);
@@ -980 +996 @@
                         off_t o;
 
-                        b = fat_block_get(bs, nodep, bnum, BLOCK_FLAGS_NONE);
+                        rc = fat_block_get(&b, bs, nodep, bnum,
+                            BLOCK_FLAGS_NONE);
+                        assert(rc == EOK);
                         for (o = pos % (bps / sizeof(fat_dentry_t));
                             o < bps / sizeof(fat_dentry_t);
@@ -1075 +1093 @@
                  * next block size boundary.
                  */
-                fat_fill_gap(bs, nodep, FAT_CLST_RES0, pos);
-                b = fat_block_get(bs, nodep, pos / bps, flags);
+                rc = fat_fill_gap(bs, nodep, FAT_CLST_RES0, pos);
+                assert(rc == EOK);
+                rc = fat_block_get(&b, bs, nodep, pos / bps, flags);
+                assert(rc == EOK);
                 (void) ipc_data_write_finalize(callid, b->data + pos % bps,
                     bytes);
@@ -1109 +1129 @@
                 }
                 /* zero fill any gaps */
-                fat_fill_gap(bs, nodep, mcl, pos);
-                b = _fat_block_get(bs, dev_handle, lcl, (pos / bps) % spc,
+                rc = fat_fill_gap(bs, nodep, mcl, pos);
+                assert(rc == EOK);
+                rc = _fat_block_get(&b, bs, dev_handle, lcl, (pos / bps) % spc,
                     flags);
+                assert(rc == EOK);
                 (void) ipc_data_write_finalize(callid, b->data + pos % bps,
                     bytes);
@@ -1121 +1143 @@
                  * node's cluster chain.
                  */
-                fat_append_clusters(bs, nodep, mcl);
+                rc = fat_append_clusters(bs, nodep, mcl);
+                assert(rc == EOK);
                 nodep->size = pos + bytes;
                 nodep->dirty = true;            /* need to sync node */
@@ -1174 +1197 @@
                  */
                 if (size == 0) {
-                        fat_chop_clusters(bs, nodep, FAT_CLST_RES0);
+                        rc = fat_chop_clusters(bs, nodep, FAT_CLST_RES0);
+                        if (rc != EOK)
+                                goto out;
                 } else {
                         fat_cluster_t lastc;
-                        (void) fat_cluster_walk(bs, dev_handle, nodep->firstc,
-                            &lastc, (size - 1) / bpc);
-                        fat_chop_clusters(bs, nodep, lastc);
+                        rc = fat_cluster_walk(bs, dev_handle, nodep->firstc,
+                            &lastc, NULL, (size - 1) / bpc);
+                        if (rc != EOK)
+                                goto out;
+                        rc = fat_chop_clusters(bs, nodep, lastc);
+                        if (rc != EOK)
+                                goto out;
                 }
                 nodep->size = size;
@@ -1185 +1214 @@
                 rc = EOK;       
         }
+out:
         fat_node_put(fn);
         ipc_answer_0(rid, rc);