bd: Add sync function to the block device API

features/filesystem/bd/BlockDevice.h

@@ -59,6 +59,15 @@ class BlockDevice
      */
     virtual int deinit() = 0;
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync()
+    {
+        return 0;
+    }
+
     /** Read blocks from a block device
      *
      *  If a failure occurs, it is not possible to determine how many bytes succeeded

features/filesystem/bd/ChainingBlockDevice.cpp

@@ -84,6 +84,18 @@ int ChainingBlockDevice::deinit()
     return 0;
 }
 
+int ChainingBlockDevice::sync()
+{
+    for (size_t i = 0; i < _bd_count; i++) {
+        int err = _bds[i]->sync();
+        if (err) {
+            return err;
+        }
+    }
+
+    return 0;
+}
+
 int ChainingBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
 {
     MBED_ASSERT(is_valid_read(addr, size));

features/filesystem/bd/ChainingBlockDevice.h

@@ -85,6 +85,12 @@ class ChainingBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to write blocks to

features/filesystem/bd/ExhaustibleBlockDevice.cpp

@@ -53,6 +53,11 @@ int ExhaustibleBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int ExhaustibleBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int ExhaustibleBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
 {
     return _bd->read(buffer, addr, size);

features/filesystem/bd/ExhaustibleBlockDevice.h

@@ -70,6 +70,12 @@ class ExhaustibleBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/bd/MBRBlockDevice.cpp

@@ -234,6 +234,11 @@ int MBRBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int MBRBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int MBRBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
 {
     MBED_ASSERT(is_valid_read(addr, size));

features/filesystem/bd/MBRBlockDevice.h

@@ -139,6 +139,12 @@ class MBRBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/bd/ObservingBlockDevice.cpp

@@ -51,6 +51,11 @@ int ObservingBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int ObservingBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int ObservingBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
 {
     return _bd->read(buffer, addr, size);

features/filesystem/bd/ObservingBlockDevice.h

@@ -56,6 +56,12 @@ class ObservingBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/bd/ProfilingBlockDevice.cpp

@@ -35,6 +35,11 @@ int ProfilingBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int ProfilingBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int ProfilingBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
 {
     int err = _bd->read(b, addr, size);

features/filesystem/bd/ProfilingBlockDevice.h

@@ -71,6 +71,12 @@ class ProfilingBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/bd/ReadOnlyBlockDevice.cpp

@@ -45,6 +45,11 @@ int ReadOnlyBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int ReadOnlyBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int ReadOnlyBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
 {
     return _bd->read(buffer, addr, size);

features/filesystem/bd/ReadOnlyBlockDevice.h

@@ -49,6 +49,12 @@ class ReadOnlyBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/bd/SlicingBlockDevice.cpp

@@ -64,6 +64,11 @@ int SlicingBlockDevice::deinit()
     return _bd->deinit();
 }
 
+int SlicingBlockDevice::sync()
+{
+    return _bd->sync();
+}
+
 int SlicingBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
 {
     MBED_ASSERT(is_valid_read(addr, size));

features/filesystem/bd/SlicingBlockDevice.h

@@ -77,6 +77,12 @@ class SlicingBlockDevice : public BlockDevice
      */
     virtual int deinit();
 
+    /** Ensure data on storage is in sync with the driver
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int sync();
+
     /** Read blocks from a block device
      *
      *  @param buffer   Buffer to read blocks into

features/filesystem/littlefs/LittleFileSystem.cpp

@@ -102,7 +102,8 @@ static int lfs_bd_erase(const struct lfs_config *c, lfs_block_t block)
 
 static int lfs_bd_sync(const struct lfs_config *c)
 {
-    return 0;
+    BlockDevice *bd = (BlockDevice *)c->context;
+    return bd->sync();
 }