WIP Fixed ENOSPC issues with zero-granularity blocks

lfs.c

@@ -886,6 +886,11 @@ split:
         // drop caches and create tail
         lfs->pcache.block = 0xffffffff;
 
+        if (ack == -1) {
+            // If we can't fit in this block, we won't fit in next block
+            return LFS_ERR_NOSPC;
+        }
+
         lfs_mdir_t tail;
         int err = lfs_dir_alloc(lfs, &tail, dir->split, dir->tail);
         if (err) {
@@ -1971,7 +1976,7 @@ int lfs_file_close(lfs_t *lfs, lfs_file_t *file) {
 }
 
 static int lfs_file_relocate(lfs_t *lfs, lfs_file_t *file) {
-relocate:;
+    while (true) {
         // just relocate what exists into new block
         lfs_block_t nblock;
         int err = lfs_alloc(lfs, &nblock);
@@ -2014,6 +2019,10 @@ relocate:;
 
         file->block = nblock;
         return 0;
+
+relocate:
+        continue;
+    }
 }
 
 static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
@@ -2067,6 +2076,7 @@ static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
                 }
 
                 break;
+
 relocate:
                 LFS_DEBUG("Bad block at %d", file->block);
                 err = lfs_file_relocate(lfs, file);
@@ -2091,6 +2101,7 @@ relocate:
 }
 
 int lfs_file_sync(lfs_t *lfs, lfs_file_t *file) {
+    while (true) {
         int err = lfs_file_flush(lfs, file);
         if (err) {
             return err;
@@ -2109,30 +2120,39 @@ int lfs_file_sync(lfs_t *lfs, lfs_file_t *file) {
             }
 
             // either update the references or inline the whole file
-        if (!(file->flags & LFS_F_INLINE)) {
             int err = lfs_dir_commit(lfs, &cwd,
-                    LFS_MKATTR(LFS_TYPE_CTZSTRUCT, file->id,
-                        &file->ctz.head, sizeof(file->ctz),
                     LFS_MKATTR(LFS_FROM_ATTRS, file->id, file->cfg->attrs, 0,
-                    NULL)));
-            if (err) {
-                return err;
-            }
-        } else {
-            int err = lfs_dir_commit(lfs, &cwd,
+                    (file->flags & LFS_F_INLINE) ?
                         LFS_MKATTR(LFS_TYPE_INLINESTRUCT, file->id,
-                            file->cache.buffer, file->ctz.size,
-                    LFS_MKATTR(LFS_FROM_ATTRS, file->id, file->cfg->attrs, 0,
-                    NULL)));
+                            file->cache.buffer, file->ctz.size, NULL) :
+                        LFS_MKATTR(LFS_TYPE_CTZSTRUCT, file->id,
+                            &file->ctz.head, sizeof(file->ctz), NULL)));
             if (err) {
-                return err;
+                if (err == LFS_ERR_NOSPC && (file->flags & LFS_F_INLINE)) {
+                    goto relocate;
                 }
+                return err;
             }
 
             file->flags &= ~LFS_F_DIRTY;
         }
 
         return 0;
+
+relocate:
+        // inline file doesn't fit anymore
+        file->block = 0xfffffffe;
+        file->off = file->pos;
+
+        lfs_alloc_ack(lfs);
+        err = lfs_file_relocate(lfs, file);
+        if (err) {
+            return err;
+        }
+
+        file->flags &= ~LFS_F_INLINE;
+        file->flags |= LFS_F_WRITING;
+    }
 }
 
 lfs_ssize_t lfs_file_read(lfs_t *lfs, lfs_file_t *file,
@@ -3304,6 +3324,7 @@ static int32_t lfs_parent(lfs_t *lfs, const lfs_block_t pair[2],
 // TODO rename to lfs_dir_relocate?
 static int lfs_relocate(lfs_t *lfs,
         const lfs_block_t oldpair[2], const lfs_block_t newpair[2]) {
+    // TODO name lfs_dir_relocate?
     // find parent
     lfs_mdir_t parent;
     int32_t tag = lfs_parent(lfs, oldpair, &parent);

tests/corrupt.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python
+
+import struct
+import sys
+import os
+
+def main(*paths):
+    # find most recent block
+    file = None
+    rev = None
+    for path in paths:
+        try:
+            nfile = open(path, 'r+b')
+            nrev, = struct.unpack('<I', nfile.read(4))
+
+            assert rev != nrev
+            if not file or ((rev - nrev) & 0x80000000):
+                file = nfile
+                rev = nrev
+        except IOError:
+            pass
+
+    # go to last commit
+    tag = 0
+    while True:
+        try:
+            ntag, = struct.unpack('<I', file.read(4))
+        except struct.error:
+            break
+
+        tag ^= ntag
+        file.seek(tag & 0xfff, os.SEEK_CUR)
+
+    # lob off last 3 bytes
+    file.seek(-((tag & 0xfff) + 3), os.SEEK_CUR)
+    file.truncate()
+
+if __name__ == "__main__":
+    main(*sys.argv[1:])

tests/test_move.sh

@@ -59,7 +59,7 @@ tests/test.py << TEST
     lfs_rename(&lfs, "b/hello", "c/hello") => 0;
     lfs_unmount(&lfs) => 0;
 TEST
-truncate -s-7 blocks/6
+tests/corrupt.py blocks/{6,7}
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
     lfs_dir_open(&lfs, &dir[0], "b") => 0;
@@ -86,8 +86,8 @@ tests/test.py << TEST
     lfs_rename(&lfs, "c/hello", "d/hello") => 0;
     lfs_unmount(&lfs) => 0;
 TEST
-truncate -s-7 blocks/8
-truncate -s-7 blocks/a
+tests/corrupt.py blocks/{8,9}
+tests/corrupt.py blocks/{a,b}
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
     lfs_dir_open(&lfs, &dir[0], "c") => 0;
@@ -166,7 +166,7 @@ tests/test.py << TEST
     lfs_rename(&lfs, "b/hi", "c/hi") => 0;
     lfs_unmount(&lfs) => 0;
 TEST
-truncate -s-7 blocks/7
+tests/corrupt.py blocks/{6,7}
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
     lfs_dir_open(&lfs, &dir[0], "b") => 0;
@@ -193,8 +193,8 @@ tests/test.py << TEST
     lfs_rename(&lfs, "c/hi", "d/hi") => 0;
     lfs_unmount(&lfs) => 0;
 TEST
-truncate -s-7 blocks/9
-truncate -s-7 blocks/b
+tests/corrupt.py blocks/{8,9}
+tests/corrupt.py blocks/{a,b}
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
     lfs_dir_open(&lfs, &dir[0], "c") => 0;

tests/test_orphan.sh

@@ -17,7 +17,7 @@ tests/test.py << TEST
 TEST
 # corrupt most recent commit, this should be the update to the previous
 # linked-list entry and should orphan the child
-truncate -s-14 blocks/8
+tests/corrupt.py blocks/{8,9}
 tests/test.py  << TEST
     lfs_mount(&lfs, &cfg) => 0;