Merge pull request #5925 from geky/bd-erase-value

bd: Add get_erase_value function to the block device API
ARMmbed · Jan 31, 2018 · 5cd30b9 · 5cd30b9
2 parents c06a42b + e6949db
commit 5cd30b9
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Showing 15 changed files with 152 additions and 8 deletions.
diff --git a/features/filesystem/bd/BlockDevice.h b/features/filesystem/bd/BlockDevice.h
@@ -94,7 +94,8 @@ class BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -144,6 +145,20 @@ class BlockDevice
         return get_program_size();
     }
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const
+    {
+        return -1;
+    }
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/ChainingBlockDevice.cpp b/features/filesystem/bd/ChainingBlockDevice.cpp
@@ -20,6 +20,7 @@
 ChainingBlockDevice::ChainingBlockDevice(BlockDevice **bds, size_t bd_count)
     : _bds(bds), _bd_count(bd_count)
     , _read_size(0), _program_size(0), _erase_size(0), _size(0)
+    , _erase_value(-1)
 {
 }
 
@@ -33,6 +34,7 @@ int ChainingBlockDevice::init()
     _read_size = 0;
     _program_size = 0;
     _erase_size = 0;
+    _erase_value = -1;
     _size = 0;
 
     // Initialize children block devices, find all sizes and
@@ -66,6 +68,13 @@ int ChainingBlockDevice::init()
             MBED_ASSERT(_erase_size > erase && is_aligned(_erase_size, erase));
         }
 
+        int value = _bds[i]->get_erase_value();
+        if (i == 0 || value == _erase_value) {
+            _erase_value = value;
+        } else {
+            _erase_value = -1;
+        }
+
         _size += _bds[i]->size();
     }
 
@@ -202,6 +211,11 @@ bd_size_t ChainingBlockDevice::get_erase_size() const
     return _erase_size;
 }
 
+int ChainingBlockDevice::get_erase_value() const
+{
+    return _erase_value;
+}
+
 bd_size_t ChainingBlockDevice::size() const
 {
     return _size;

diff --git a/features/filesystem/bd/ChainingBlockDevice.h b/features/filesystem/bd/ChainingBlockDevice.h
@@ -113,7 +113,8 @@ class ChainingBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -141,6 +142,17 @@ class ChainingBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes
@@ -154,6 +166,7 @@ class ChainingBlockDevice : public BlockDevice
     bd_size_t _program_size;
     bd_size_t _erase_size;
     bd_size_t _size;
+    int _erase_value;
 };
 
 

diff --git a/features/filesystem/bd/ExhaustibleBlockDevice.cpp b/features/filesystem/bd/ExhaustibleBlockDevice.cpp
@@ -107,6 +107,11 @@ bd_size_t ExhaustibleBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int ExhaustibleBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t ExhaustibleBlockDevice::size() const
 {
     return _bd->size();

diff --git a/features/filesystem/bd/ExhaustibleBlockDevice.h b/features/filesystem/bd/ExhaustibleBlockDevice.h
@@ -98,7 +98,8 @@ class ExhaustibleBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -124,6 +125,17 @@ class ExhaustibleBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/MBRBlockDevice.cpp b/features/filesystem/bd/MBRBlockDevice.cpp
@@ -272,6 +272,11 @@ bd_size_t MBRBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int MBRBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t MBRBlockDevice::size() const
 {
     return _size;

diff --git a/features/filesystem/bd/MBRBlockDevice.h b/features/filesystem/bd/MBRBlockDevice.h
@@ -167,7 +167,8 @@ class MBRBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -195,6 +196,17 @@ class MBRBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/ObservingBlockDevice.cpp b/features/filesystem/bd/ObservingBlockDevice.cpp
@@ -96,6 +96,11 @@ bd_size_t ObservingBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int ObservingBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t ObservingBlockDevice::size() const
 {
     return _bd->size();

diff --git a/features/filesystem/bd/ObservingBlockDevice.h b/features/filesystem/bd/ObservingBlockDevice.h
@@ -84,7 +84,8 @@ class ObservingBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -110,6 +111,17 @@ class ObservingBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/ProfilingBlockDevice.cpp b/features/filesystem/bd/ProfilingBlockDevice.cpp
@@ -82,6 +82,11 @@ bd_size_t ProfilingBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int ProfilingBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t ProfilingBlockDevice::size() const
 {
     return _bd->size();

diff --git a/features/filesystem/bd/ProfilingBlockDevice.h b/features/filesystem/bd/ProfilingBlockDevice.h
@@ -99,7 +99,8 @@ class ProfilingBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -127,6 +128,17 @@ class ProfilingBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and you can program storage
+     *  containing that value without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/ReadOnlyBlockDevice.cpp b/features/filesystem/bd/ReadOnlyBlockDevice.cpp
@@ -82,6 +82,11 @@ bd_size_t ReadOnlyBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int ReadOnlyBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t ReadOnlyBlockDevice::size() const
 {
     return _bd->size();

diff --git a/features/filesystem/bd/ReadOnlyBlockDevice.h b/features/filesystem/bd/ReadOnlyBlockDevice.h
@@ -77,7 +77,8 @@ class ReadOnlyBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -103,6 +104,17 @@ class ReadOnlyBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes

diff --git a/features/filesystem/bd/SlicingBlockDevice.cpp b/features/filesystem/bd/SlicingBlockDevice.cpp
@@ -102,6 +102,11 @@ bd_size_t SlicingBlockDevice::get_erase_size() const
     return _bd->get_erase_size();
 }
 
+int SlicingBlockDevice::get_erase_value() const
+{
+    return _bd->get_erase_value();
+}
+
 bd_size_t SlicingBlockDevice::size() const
 {
     return _stop - _start;

diff --git a/features/filesystem/bd/SlicingBlockDevice.h b/features/filesystem/bd/SlicingBlockDevice.h
@@ -105,7 +105,8 @@ class SlicingBlockDevice : public BlockDevice
 
     /** Erase blocks on a block device
      *
-     *  The state of an erased block is undefined until it has been programmed
+     *  The state of an erased block is undefined until it has been programmed,
+     *  unless get_erase_value returns a non-negative byte value
      *
      *  @param addr     Address of block to begin erasing
      *  @param size     Size to erase in bytes, must be a multiple of erase block size
@@ -133,6 +134,17 @@ class SlicingBlockDevice : public BlockDevice
      */
     virtual bd_size_t get_erase_size() const;
 
+    /** Get the value of storage when erased
+     *
+     *  If get_erase_value returns a non-negative byte value, the underlying
+     *  storage is set to that value when erased, and storage containing
+     *  that value can be programmed without another erase.
+     *
+     *  @return         The value of storage when erased, or -1 if you can't
+     *                  rely on the value of erased storage
+     */
+    virtual int get_erase_value() const;
+
     /** Get the total size of the underlying device
      *
      *  @return         Size of the underlying device in bytes