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Addes the ARM mbed littlefs to NuttX
Squashed commit of the following: Author: Gregory Nutt <gnutt@nuttx.org> fs/littlefs: Fix some compilation errors. fs/littlefs: Brings code a little closer to NuttX coding standard. Not 100%, but closer. fs/littlefs: Convert all C++ style comments to C comments. Author: lihaichen <li8303@163.com> fs/littlefs: Adds port of the mbed littlefs. depends on !DISABLE_MOUNTPOINT && MTD_BYTE_WRITE register_mtddriver("/dev/w25", mtd, 0755, NULL); mount("/dev/w25", "/w25", "littlefs", 0, NULL);
This commit is contained in:
lihaichen
Gregory Nutt
@@ -88,6 +88,7 @@ source fs/smartfs/Kconfig
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source fs/binfs/Kconfig
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source fs/binfs/Kconfig
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source fs/procfs/Kconfig
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source fs/procfs/Kconfig
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source fs/spiffs/Kconfig
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source fs/spiffs/Kconfig
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source fs/littlefs/Kconfig
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source fs/unionfs/Kconfig
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source fs/unionfs/Kconfig
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source fs/userfs/Kconfig
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source fs/userfs/Kconfig
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source fs/hostfs/Kconfig
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source fs/hostfs/Kconfig
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@@ -77,6 +77,7 @@ include spiffs/Make.defs
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include unionfs/Make.defs
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include unionfs/Make.defs
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include userfs/Make.defs
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include userfs/Make.defs
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include hostfs/Make.defs
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include hostfs/Make.defs
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include littlefs/Make.defs
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endif
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endif
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endif
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endif
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File diff suppressed because it is too large
Load Diff
@@ -0,0 +1,9 @@
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config FS_LITTLEFS
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bool "LITTLEFS File System"
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default n
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select FS_READABLE
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select FS_WRITABLE
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depends on !DISABLE_MOUNTPOINT && MTD_BYTE_WRITE && EXPERIMENTAL
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---help---
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Build the LITTLEFS file system. https://github.com/ARMmbed/littlefs.
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@@ -0,0 +1,55 @@
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#############################################################################
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# fs/littlefs/lfs.c
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#
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# This file is a part of NuttX:
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#
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# Copyright (C) 2019 Gregory Nutt. All rights reserved.
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#
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# Ported by:
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#
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# Copyright (C) 2019 Pinecone Inc. All rights reserved.
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# Author: lihaichen <li8303@163.com>
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#
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# This port derives from ARM mbed logic which has a compatible 3-clause
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# BSD license:
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#
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# Copyright (c) 2017, Arm Limited. All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions
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# are met:
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#
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# 1. Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# 2. Redistributions in binary form must reproduce the above copyright
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# notice, this list of conditions and the following disclaimer in
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# the documentation and/or other materials provided with the
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# distribution.
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# 3. Neither the name NuttX nor the names of its contributors may be
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# used to endorse or promote products derived from this software
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# without specific prior written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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# POSSIBILITY OF SUCH DAMAGE.
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#
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#############################################################################
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ifeq ($(CONFIG_FS_LITTLEFS),y)
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# Files required for littlefs file system support
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CSRCS += lfs.c lfs_util.c lfs_vfs.c
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DEPPATH += --dep-path littlefs
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VPATH += :littlefs
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endif
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@@ -0,0 +1,220 @@
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## usage
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depends on !DISABLE_MOUNTPOINT && MTD_BYTE_WRITE
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1. register_mtddriver("/dev/w25", mtd, 0755, NULL);
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2. mount("/dev/w25", "/w25", "littlefs", 0, NULL);
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## need to do
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1. no format tool, mount auto format.
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## The little filesystem
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A little fail-safe filesystem designed for embedded systems.
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```
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| | | .---._____
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.-----. | |
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--|o |---| littlefs |
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--| |---| |
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'-----' '----------'
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| | |
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```
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**Bounded RAM/ROM** - The littlefs is designed to work with a limited amount
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of memory. Recursion is avoided and dynamic memory is limited to configurable
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buffers that can be provided statically.
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**Power-loss resilient** - The littlefs is designed for systems that may have
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random power failures. The littlefs has strong copy-on-write guarantees and
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storage on disk is always kept in a valid state.
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**Wear leveling** - Since the most common form of embedded storage is erodible
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flash memories, littlefs provides a form of dynamic wear leveling for systems
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that can not fit a full flash translation layer.
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## Example
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Here's a simple example that updates a file named `boot_count` every time
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main runs. The program can be interrupted at any time without losing track
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of how many times it has been booted and without corrupting the filesystem:
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``` c
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#include "lfs.h"
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/* variables used by the filesystem */
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lfs_t lfs;
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lfs_file_t file;
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/* configuration of the filesystem is provided by this struct */
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const struct lfs_config cfg =
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{
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/* block device operations */
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.read = user_provided_block_device_read,
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.prog = user_provided_block_device_prog,
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.erase = user_provided_block_device_erase,
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.sync = user_provided_block_device_sync,
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/* block device configuration */
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.read_size = 16,
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.prog_size = 16,
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.block_size = 4096,
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.block_count = 128,
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.lookahead = 128,
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};
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/* entry point */
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int main(void)
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{
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/* mount the filesystem */
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int err = lfs_mount(&lfs, &cfg);
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/* reformat if we can't mount the filesystem
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* this should only happen on the first boot
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*/
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if (err)
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{
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lfs_format(&lfs, &cfg);
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lfs_mount(&lfs, &cfg);
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}
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/* read current count */
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uint32_t boot_count = 0;
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lfs_file_open(&lfs, &file, "boot_count", LFS_O_RDWR | LFS_O_CREAT);
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lfs_file_read(&lfs, &file, &boot_count, sizeof(boot_count));
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/* update boot count */
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boot_count += 1;
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lfs_file_rewind(&lfs, &file);
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lfs_file_write(&lfs, &file, &boot_count, sizeof(boot_count));
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/* remember the storage is not updated until the file is closed successfully */
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lfs_file_close(&lfs, &file);
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/* release any resources we were using */
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lfs_unmount(&lfs);
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/* print the boot count */
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printf("boot_count: %d\n", boot_count);
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}
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```
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## Usage
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Detailed documentation (or at least as much detail as is currently available)
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can be found in the comments in [lfs.h](lfs.h).
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As you may have noticed, littlefs takes in a configuration structure that
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defines how the filesystem operates. The configuration struct provides the
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filesystem with the block device operations and dimensions, tweakable
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parameters that tradeoff memory usage for performance, and optional
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static buffers if the user wants to avoid dynamic memory.
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The state of the littlefs is stored in the `lfs_t` type which is left up
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to the user to allocate, allowing multiple filesystems to be in use
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simultaneously. With the `lfs_t` and configuration struct, a user can
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format a block device or mount the filesystem.
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Once mounted, the littlefs provides a full set of POSIX-like file and
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directory functions, with the deviation that the allocation of filesystem
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structures must be provided by the user.
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All POSIX operations, such as remove and rename, are atomic, even in event
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of power-loss. Additionally, no file updates are actually committed to the
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filesystem until sync or close is called on the file.
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## Other notes
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All littlefs have the potential to return a negative error code. The errors
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can be either one of those found in the `enum lfs_error` in [lfs.h](lfs.h),
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or an error returned by the user's block device operations.
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In the configuration struct, the `prog` and `erase` function provided by the
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user may return a `LFS_ERR_CORRUPT` error if the implementation already can
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detect corrupt blocks. However, the wear leveling does not depend on the return
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code of these functions, instead all data is read back and checked for
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integrity.
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If your storage caches writes, make sure that the provided `sync` function
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flushes all the data to memory and ensures that the next read fetches the data
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from memory, otherwise data integrity can not be guaranteed. If the `write`
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function does not perform caching, and therefore each `read` or `write` call
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hits the memory, the `sync` function can simply return 0.
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## Reference material
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[DESIGN.md](DESIGN.md) - DESIGN.md contains a fully detailed dive into how
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littlefs actually works. I would encourage you to read it since the
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solutions and tradeoffs at work here are quite interesting.
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[SPEC.md](SPEC.md) - SPEC.md contains the on-disk specification of littlefs
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with all the nitty-gritty details. Can be useful for developing tooling.
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## Testing
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The littlefs comes with a test suite designed to run on a PC using the
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[emulated block device](emubd/lfs_emubd.h) found in the emubd directory.
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The tests assume a Linux environment and can be started with make:
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``` bash
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make test
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```
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## License
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The littlefs is provided under the [BSD-3-Clause](https://spdx.org/licenses/BSD-3-Clause.html)
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license. See [LICENSE.md](LICENSE.md) for more information. Contributions to
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this project are accepted under the same license.
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Individual files contain the following tag instead of the full license text.
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SPDX-License-Identifier: BSD-3-Clause
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|
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This enables machine processing of license information based on the SPDX
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License Identifiers that are here available: http://spdx.org/licenses/
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## Related projects
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[Mbed OS](https://github.com/ARMmbed/mbed-os/tree/master/features/filesystem/littlefs) -
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The easiest way to get started with littlefs is to jump into [Mbed](https://os.mbed.com/),
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which already has block device drivers for most forms of embedded storage. The
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littlefs is available in Mbed OS as the [LittleFileSystem](https://os.mbed.com/docs/latest/reference/littlefilesystem.html)
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class.
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[littlefs-fuse](https://github.com/geky/littlefs-fuse) - A [FUSE](https://github.com/libfuse/libfuse)
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wrapper for littlefs. The project allows you to mount littlefs directly on a
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Linux machine. Can be useful for debugging littlefs if you have an SD card
|
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handy.
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[littlefs-js](https://github.com/geky/littlefs-js) - A javascript wrapper for
|
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littlefs. I'm not sure why you would want this, but it is handy for demos.
|
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You can see it in action [here](http://littlefs.geky.net/demo.html).
|
||||||
|
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[mklfs](https://github.com/whitecatboard/Lua-RTOS-ESP32/tree/master/components/mklfs/src) -
|
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A command line tool built by the [Lua RTOS](https://github.com/whitecatboard/Lua-RTOS-ESP32)
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|
guys for making littlefs images from a host PC. Supports Windows, Mac OS,
|
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and Linux.
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|
||||||
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[SPIFFS](https://github.com/pellepl/spiffs) - Another excellent embedded
|
||||||
|
filesystem for NOR flash. As a more traditional logging filesystem with full
|
||||||
|
static wear-leveling, SPIFFS will likely outperform littlefs on small
|
||||||
|
memories such as the internal flash on microcontrollers.
|
||||||
|
|
||||||
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[Dhara](https://github.com/dlbeer/dhara) - An interesting NAND flash
|
||||||
|
translation layer designed for small MCUs. It offers static wear-leveling and
|
||||||
|
power-resilience with only a fixed O(|address|) pointer structure stored on
|
||||||
|
each block and in RAM.
|
||||||
@@ -0,0 +1,370 @@
|
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|
## The little filesystem technical specification
|
||||||
|
|
||||||
|
This is the technical specification of the little filesystem. This document
|
||||||
|
covers the technical details of how the littlefs is stored on disk for
|
||||||
|
introspection and tooling development. This document assumes you are
|
||||||
|
familiar with the design of the littlefs, for more info on how littlefs
|
||||||
|
works check out [DESIGN.md](DESIGN.md).
|
||||||
|
|
||||||
|
```
|
||||||
|
| | | .---._____
|
||||||
|
.-----. | |
|
||||||
|
--|o |---| littlefs |
|
||||||
|
--| |---| |
|
||||||
|
'-----' '----------'
|
||||||
|
| | |
|
||||||
|
```
|
||||||
|
|
||||||
|
## Some important details
|
||||||
|
|
||||||
|
- The littlefs is a block-based filesystem. This is, the disk is divided into
|
||||||
|
an array of evenly sized blocks that are used as the logical unit of storage
|
||||||
|
in littlefs. Block pointers are stored in 32 bits.
|
||||||
|
|
||||||
|
- There is no explicit free-list stored on disk, the littlefs only knows what
|
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|
is in use in the filesystem.
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||||||
|
|
||||||
|
- The littlefs uses the value of 0xffffffff to represent a null block-pointer.
|
||||||
|
|
||||||
|
- All values in littlefs are stored in little-endian byte order.
|
||||||
|
|
||||||
|
## Directories / Metadata pairs
|
||||||
|
|
||||||
|
Metadata pairs form the backbone of the littlefs and provide a system for
|
||||||
|
atomic updates. Even the superblock is stored in a metadata pair.
|
||||||
|
|
||||||
|
As their name suggests, a metadata pair is stored in two blocks, with one block
|
||||||
|
acting as a redundant backup in case the other is corrupted. These two blocks
|
||||||
|
could be anywhere in the disk and may not be next to each other, so any
|
||||||
|
pointers to directory pairs need to be stored as two block pointers.
|
||||||
|
|
||||||
|
Here's the layout of metadata blocks on disk:
|
||||||
|
|
||||||
|
| offset | size | description |
|
||||||
|
|--------|---------------|----------------|
|
||||||
|
| 0x00 | 32 bits | revision count |
|
||||||
|
| 0x04 | 32 bits | dir size |
|
||||||
|
| 0x08 | 64 bits | tail pointer |
|
||||||
|
| 0x10 | size-16 bytes | dir entries |
|
||||||
|
| 0x00+s | 32 bits | CRC |
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||||||
|
**Revision count** - Incremented every update, only the uncorrupted
|
||||||
|
metadata-block with the most recent revision count contains the valid metadata.
|
||||||
|
Comparison between revision counts must use sequence comparison since the
|
||||||
|
revision counts may overflow.
|
||||||
|
|
||||||
|
**Dir size** - Size in bytes of the contents in the current metadata block,
|
||||||
|
including the metadata-pair metadata. Additionally, the highest bit of the
|
||||||
|
dir size may be set to indicate that the directory's contents continue on the
|
||||||
|
next metadata-pair pointed to by the tail pointer.
|
||||||
|
|
||||||
|
**Tail pointer** - Pointer to the next metadata-pair in the filesystem.
|
||||||
|
A null pair-pointer (0xffffffff, 0xffffffff) indicates the end of the list.
|
||||||
|
If the highest bit in the dir size is set, this points to the next
|
||||||
|
metadata-pair in the current directory, otherwise it points to an arbitrary
|
||||||
|
metadata-pair. Starting with the superblock, the tail-pointers form a
|
||||||
|
linked-list containing all metadata-pairs in the filesystem.
|
||||||
|
|
||||||
|
**CRC** - 32 bit CRC used to detect corruption from power-lost, from block
|
||||||
|
end-of-life, or just from noise on the storage bus. The CRC is appended to
|
||||||
|
the end of each metadata-block. The littlefs uses the standard CRC-32, which
|
||||||
|
uses a polynomial of 0x04c11db7, initialized with 0xffffffff.
|
||||||
|
|
||||||
|
Here's an example of a simple directory stored on disk:
|
||||||
|
```
|
||||||
|
(32 bits) revision count = 10 (0x0000000a)
|
||||||
|
(32 bits) dir size = 154 bytes, end of dir (0x0000009a)
|
||||||
|
(64 bits) tail pointer = 37, 36 (0x00000025, 0x00000024)
|
||||||
|
(32 bits) CRC = 0xc86e3106
|
||||||
|
|
||||||
|
00000000: 0a 00 00 00 9a 00 00 00 25 00 00 00 24 00 00 00 ........%...$...
|
||||||
|
00000010: 22 08 00 03 05 00 00 00 04 00 00 00 74 65 61 22 "...........tea"
|
||||||
|
00000020: 08 00 06 07 00 00 00 06 00 00 00 63 6f 66 66 65 ...........coffe
|
||||||
|
00000030: 65 22 08 00 04 09 00 00 00 08 00 00 00 73 6f 64 e"...........sod
|
||||||
|
00000040: 61 22 08 00 05 1d 00 00 00 1c 00 00 00 6d 69 6c a"...........mil
|
||||||
|
00000050: 6b 31 22 08 00 05 1f 00 00 00 1e 00 00 00 6d 69 k1"...........mi
|
||||||
|
00000060: 6c 6b 32 22 08 00 05 21 00 00 00 20 00 00 00 6d lk2"...!... ...m
|
||||||
|
00000070: 69 6c 6b 33 22 08 00 05 23 00 00 00 22 00 00 00 ilk3"...#..."...
|
||||||
|
00000080: 6d 69 6c 6b 34 22 08 00 05 25 00 00 00 24 00 00 milk4"...%...$..
|
||||||
|
00000090: 00 6d 69 6c 6b 35 06 31 6e c8 .milk5.1n.
|
||||||
|
```
|
||||||
|
|
||||||
|
A note about the tail pointer linked-list: Normally, this linked-list is
|
||||||
|
threaded through the entire filesystem. However, after power-loss this
|
||||||
|
linked-list may become out of sync with the rest of the filesystem.
|
||||||
|
- The linked-list may contain a directory that has actually been removed
|
||||||
|
- The linked-list may contain a metadata pair that has not been updated after
|
||||||
|
a block in the pair has gone bad.
|
||||||
|
|
||||||
|
The threaded linked-list must be checked for these errors before it can be
|
||||||
|
used reliably. Fortunately, the threaded linked-list can simply be ignored
|
||||||
|
if littlefs is mounted read-only.
|
||||||
|
|
||||||
|
## Entries
|
||||||
|
|
||||||
|
Each metadata block contains a series of entries that follow a standard
|
||||||
|
layout. An entry contains the type of the entry, along with a section for
|
||||||
|
entry-specific data, attributes, and a name.
|
||||||
|
|
||||||
|
Here's the layout of entries on disk:
|
||||||
|
|
||||||
|
| offset | size | description |
|
||||||
|
|---------|------------------------|----------------------------|
|
||||||
|
| 0x0 | 8 bits | entry type |
|
||||||
|
| 0x1 | 8 bits | entry length |
|
||||||
|
| 0x2 | 8 bits | attribute length |
|
||||||
|
| 0x3 | 8 bits | name length |
|
||||||
|
| 0x4 | entry length bytes | entry-specific data |
|
||||||
|
| 0x4+e | attribute length bytes | system-specific attributes |
|
||||||
|
| 0x4+e+a | name length bytes | entry name |
|
||||||
|
|
||||||
|
**Entry type** - Type of the entry, currently this is limited to the following:
|
||||||
|
- 0x11 - file entry
|
||||||
|
- 0x22 - directory entry
|
||||||
|
- 0x2e - superblock entry
|
||||||
|
|
||||||
|
Additionally, the type is broken into two 4 bit nibbles, with the upper nibble
|
||||||
|
specifying the type's data structure used when scanning the filesystem. The
|
||||||
|
lower nibble clarifies the type further when multiple entries share the same
|
||||||
|
data structure.
|
||||||
|
|
||||||
|
The highest bit is reserved for marking the entry as "moved". If an entry
|
||||||
|
is marked as "moved", the entry may also exist somewhere else in the
|
||||||
|
filesystem. If the entry exists elsewhere, this entry must be treated as
|
||||||
|
though it does not exist.
|
||||||
|
|
||||||
|
**Entry length** - Length in bytes of the entry-specific data. This does
|
||||||
|
not include the entry type size, attributes, or name. The full size in bytes
|
||||||
|
of the entry is 4 + entry length + attribute length + name length.
|
||||||
|
|
||||||
|
**Attribute length** - Length of system-specific attributes in bytes. Since
|
||||||
|
attributes are system specific, there is not much guarantee on the values in
|
||||||
|
this section, and systems are expected to work even when it is empty. See the
|
||||||
|
[attributes](#entry-attributes) section for more details.
|
||||||
|
|
||||||
|
**Name length** - Length of the entry name. Entry names are stored as UTF8,
|
||||||
|
although most systems will probably only support ASCII. Entry names can not
|
||||||
|
contain '/' and can not be '.' or '..' as these are a part of the syntax of
|
||||||
|
filesystem paths.
|
||||||
|
|
||||||
|
Here's an example of a simple entry stored on disk:
|
||||||
|
```
|
||||||
|
(8 bits) entry type = file (0x11)
|
||||||
|
(8 bits) entry length = 8 bytes (0x08)
|
||||||
|
(8 bits) attribute length = 0 bytes (0x00)
|
||||||
|
(8 bits) name length = 12 bytes (0x0c)
|
||||||
|
(8 bytes) entry data = 05 00 00 00 20 00 00 00
|
||||||
|
(12 bytes) entry name = smallavacado
|
||||||
|
|
||||||
|
00000000: 11 08 00 0c 05 00 00 00 20 00 00 00 73 6d 61 6c ........ ...smal
|
||||||
|
00000010: 6c 61 76 61 63 61 64 6f lavacado
|
||||||
|
```
|
||||||
|
|
||||||
|
## Superblock
|
||||||
|
|
||||||
|
The superblock is the anchor for the littlefs. The superblock is stored as
|
||||||
|
a metadata pair containing a single superblock entry. It is through the
|
||||||
|
superblock that littlefs can access the rest of the filesystem.
|
||||||
|
|
||||||
|
The superblock can always be found in blocks 0 and 1, however fetching the
|
||||||
|
superblock requires knowing the block size. The block size can be guessed by
|
||||||
|
searching the beginning of disk for the string "littlefs", although currently
|
||||||
|
the filesystems relies on the user providing the correct block size.
|
||||||
|
|
||||||
|
The superblock is the most valuable block in the filesystem. It is updated
|
||||||
|
very rarely, only during format or when the root directory must be moved. It
|
||||||
|
is encouraged to always write out both superblock pairs even though it is not
|
||||||
|
required.
|
||||||
|
|
||||||
|
Here's the layout of the superblock entry:
|
||||||
|
|
||||||
|
| offset | size | description |
|
||||||
|
|--------|------------------------|----------------------------------------|
|
||||||
|
| 0x00 | 8 bits | entry type (0x2e for superblock entry) |
|
||||||
|
| 0x01 | 8 bits | entry length (20 bytes) |
|
||||||
|
| 0x02 | 8 bits | attribute length |
|
||||||
|
| 0x03 | 8 bits | name length (8 bytes) |
|
||||||
|
| 0x04 | 64 bits | root directory |
|
||||||
|
| 0x0c | 32 bits | block size |
|
||||||
|
| 0x10 | 32 bits | block count |
|
||||||
|
| 0x14 | 32 bits | version |
|
||||||
|
| 0x18 | attribute length bytes | system-specific attributes |
|
||||||
|
| 0x18+a | 8 bytes | magic string ("littlefs") |
|
||||||
|
|
||||||
|
**Root directory** - Pointer to the root directory's metadata pair.
|
||||||
|
|
||||||
|
**Block size** - Size of the logical block size used by the filesystem.
|
||||||
|
|
||||||
|
**Block count** - Number of blocks in the filesystem.
|
||||||
|
|
||||||
|
**Version** - The littlefs version encoded as a 32 bit value. The upper 16 bits
|
||||||
|
encodes the major version, which is incremented when a breaking-change is
|
||||||
|
introduced in the filesystem specification. The lower 16 bits encodes the
|
||||||
|
minor version, which is incremented when a backwards-compatible change is
|
||||||
|
introduced. Non-standard Attribute changes do not change the version. This
|
||||||
|
specification describes version 1.1 (0x00010001), which is the first version
|
||||||
|
of littlefs.
|
||||||
|
|
||||||
|
**Magic string** - The magic string "littlefs" takes the place of an entry
|
||||||
|
name.
|
||||||
|
|
||||||
|
Here's an example of a complete superblock:
|
||||||
|
```
|
||||||
|
(32 bits) revision count = 3 (0x00000003)
|
||||||
|
(32 bits) dir size = 52 bytes, end of dir (0x00000034)
|
||||||
|
(64 bits) tail pointer = 3, 2 (0x00000003, 0x00000002)
|
||||||
|
(8 bits) entry type = superblock (0x2e)
|
||||||
|
(8 bits) entry length = 20 bytes (0x14)
|
||||||
|
(8 bits) attribute length = 0 bytes (0x00)
|
||||||
|
(8 bits) name length = 8 bytes (0x08)
|
||||||
|
(64 bits) root directory = 3, 2 (0x00000003, 0x00000002)
|
||||||
|
(32 bits) block size = 512 bytes (0x00000200)
|
||||||
|
(32 bits) block count = 1024 blocks (0x00000400)
|
||||||
|
(32 bits) version = 1.1 (0x00010001)
|
||||||
|
(8 bytes) magic string = littlefs
|
||||||
|
(32 bits) CRC = 0xc50b74fa
|
||||||
|
|
||||||
|
00000000: 03 00 00 00 34 00 00 00 03 00 00 00 02 00 00 00 ....4...........
|
||||||
|
00000010: 2e 14 00 08 03 00 00 00 02 00 00 00 00 02 00 00 ................
|
||||||
|
00000020: 00 04 00 00 01 00 01 00 6c 69 74 74 6c 65 66 73 ........littlefs
|
||||||
|
00000030: fa 74 0b c5 .t..
|
||||||
|
```
|
||||||
|
|
||||||
|
## Directory entries
|
||||||
|
|
||||||
|
Directories are stored in entries with a pointer to the first metadata pair
|
||||||
|
in the directory. Keep in mind that a directory may be composed of multiple
|
||||||
|
metadata pairs connected by the tail pointer when the highest bit in the dir
|
||||||
|
size is set.
|
||||||
|
|
||||||
|
Here's the layout of a directory entry:
|
||||||
|
|
||||||
|
| offset | size | description |
|
||||||
|
|--------|------------------------|-----------------------------------------|
|
||||||
|
| 0x0 | 8 bits | entry type (0x22 for directory entries) |
|
||||||
|
| 0x1 | 8 bits | entry length (8 bytes) |
|
||||||
|
| 0x2 | 8 bits | attribute length |
|
||||||
|
| 0x3 | 8 bits | name length |
|
||||||
|
| 0x4 | 64 bits | directory pointer |
|
||||||
|
| 0xc | attribute length bytes | system-specific attributes |
|
||||||
|
| 0xc+a | name length bytes | directory name |
|
||||||
|
|
||||||
|
**Directory pointer** - Pointer to the first metadata pair in the directory.
|
||||||
|
|
||||||
|
Here's an example of a directory entry:
|
||||||
|
```
|
||||||
|
(8 bits) entry type = directory (0x22)
|
||||||
|
(8 bits) entry length = 8 bytes (0x08)
|
||||||
|
(8 bits) attribute length = 0 bytes (0x00)
|
||||||
|
(8 bits) name length = 3 bytes (0x03)
|
||||||
|
(64 bits) directory pointer = 5, 4 (0x00000005, 0x00000004)
|
||||||
|
(3 bytes) name = tea
|
||||||
|
|
||||||
|
00000000: 22 08 00 03 05 00 00 00 04 00 00 00 74 65 61 "...........tea
|
||||||
|
```
|
||||||
|
|
||||||
|
## File entries
|
||||||
|
|
||||||
|
Files are stored in entries with a pointer to the head of the file and the
|
||||||
|
size of the file. This is enough information to determine the state of the
|
||||||
|
CTZ skip-list that is being referenced.
|
||||||
|
|
||||||
|
How files are actually stored on disk is a bit complicated. The full
|
||||||
|
explanation of CTZ skip-lists can be found in [DESIGN.md](DESIGN.md#ctz-skip-lists).
|
||||||
|
|
||||||
|
A terribly quick summary: For every nth block where n is divisible by 2^x,
|
||||||
|
the block contains a pointer to block n-2^x. These pointers are stored in
|
||||||
|
increasing order of x in each block of the file preceding the data in the
|
||||||
|
block.
|
||||||
|
|
||||||
|
The maximum number of pointers in a block is bounded by the maximum file size
|
||||||
|
divided by the block size. With 32 bits for file size, this results in a
|
||||||
|
minimum block size of 104 bytes.
|
||||||
|
|
||||||
|
Here's the layout of a file entry:
|
||||||
|
|
||||||
|
| offset | size | description |
|
||||||
|
|--------|------------------------|------------------------------------|
|
||||||
|
| 0x0 | 8 bits | entry type (0x11 for file entries) |
|
||||||
|
| 0x1 | 8 bits | entry length (8 bytes) |
|
||||||
|
| 0x2 | 8 bits | attribute length |
|
||||||
|
| 0x3 | 8 bits | name length |
|
||||||
|
| 0x4 | 32 bits | file head |
|
||||||
|
| 0x8 | 32 bits | file size |
|
||||||
|
| 0xc | attribute length bytes | system-specific attributes |
|
||||||
|
| 0xc+a | name length bytes | directory name |
|
||||||
|
|
||||||
|
**File head** - Pointer to the block that is the head of the file's CTZ
|
||||||
|
skip-list.
|
||||||
|
|
||||||
|
**File size** - Size of file in bytes.
|
||||||
|
|
||||||
|
Here's an example of a file entry:
|
||||||
|
```
|
||||||
|
(8 bits) entry type = file (0x11)
|
||||||
|
(8 bits) entry length = 8 bytes (0x08)
|
||||||
|
(8 bits) attribute length = 0 bytes (0x00)
|
||||||
|
(8 bits) name length = 12 bytes (0x03)
|
||||||
|
(32 bits) file head = 543 (0x0000021f)
|
||||||
|
(32 bits) file size = 256 KB (0x00040000)
|
||||||
|
(12 bytes) name = largeavacado
|
||||||
|
|
||||||
|
00000000: 11 08 00 0c 1f 02 00 00 00 00 04 00 6c 61 72 67 ............larg
|
||||||
|
00000010: 65 61 76 61 63 61 64 6f eavacado
|
||||||
|
```
|
||||||
|
|
||||||
|
## Entry attributes
|
||||||
|
|
||||||
|
Each dir entry can have up to 256 bytes of system-specific attributes. Since
|
||||||
|
these attributes are system-specific, they may not be portable between
|
||||||
|
different systems. For this reason, all attributes must be optional. A minimal
|
||||||
|
littlefs driver must be able to get away with supporting no attributes at all.
|
||||||
|
|
||||||
|
For some level of portability, littlefs has a simple scheme for attributes.
|
||||||
|
Each attribute is prefixes with an 8-bit type that indicates what the attribute
|
||||||
|
is. The length of attributes may also be determined from this type. Attributes
|
||||||
|
in an entry should be sorted based on portability, since attribute parsing
|
||||||
|
will end when it hits the first attribute it does not understand.
|
||||||
|
|
||||||
|
Each system should choose a 4-bit value to prefix all attribute types with to
|
||||||
|
avoid conflicts with other systems. Additionally, littlefs drivers that support
|
||||||
|
attributes should provide a "ignore attributes" flag to users in case attribute
|
||||||
|
conflicts do occur.
|
||||||
|
|
||||||
|
Attribute types prefixes with 0x0 and 0xf are currently reserved for future
|
||||||
|
standard attributes. Standard attributes will be added to this document in
|
||||||
|
that case.
|
||||||
|
|
||||||
|
Here's an example of non-standard time attribute:
|
||||||
|
```
|
||||||
|
(8 bits) attribute type = time (0xc1)
|
||||||
|
(72 bits) time in seconds = 1506286115 (0x0059c81a23)
|
||||||
|
|
||||||
|
00000000: c1 23 1a c8 59 00 .#..Y.
|
||||||
|
```
|
||||||
|
|
||||||
|
Here's an example of non-standard permissions attribute:
|
||||||
|
```
|
||||||
|
(8 bits) attribute type = permissions (0xc2)
|
||||||
|
(16 bits) permission bits = rw-rw-r-- (0x01b4)
|
||||||
|
|
||||||
|
00000000: c2 b4 01 ...
|
||||||
|
```
|
||||||
|
|
||||||
|
Here's what a dir entry may look like with these attributes:
|
||||||
|
```
|
||||||
|
(8 bits) entry type = file (0x11)
|
||||||
|
(8 bits) entry length = 8 bytes (0x08)
|
||||||
|
(8 bits) attribute length = 9 bytes (0x09)
|
||||||
|
(8 bits) name length = 12 bytes (0x0c)
|
||||||
|
(8 bytes) entry data = 05 00 00 00 20 00 00 00
|
||||||
|
(8 bits) attribute type = time (0xc1)
|
||||||
|
(72 bits) time in seconds = 1506286115 (0x0059c81a23)
|
||||||
|
(8 bits) attribute type = permissions (0xc2)
|
||||||
|
(16 bits) permission bits = rw-rw-r-- (0x01b4)
|
||||||
|
(12 bytes) entry name = smallavacado
|
||||||
|
|
||||||
|
00000000: 11 08 09 0c 05 00 00 00 20 00 00 00 c1 23 1a c8 ........ ....#..
|
||||||
|
00000010: 59 00 c2 b4 01 73 6d 61 6c 6c 61 76 61 63 61 64 Y....smallavacad
|
||||||
|
00000020: 6f o
|
||||||
|
```
|
||||||
+3367
File diff suppressed because it is too large
Load Diff
File diff suppressed because it is too large
Load Diff
@@ -0,0 +1,83 @@
|
|||||||
|
/****************************************************************************
|
||||||
|
* fs/littlefs/lfs_util.c
|
||||||
|
*
|
||||||
|
* This file is a part of NuttX:
|
||||||
|
*
|
||||||
|
* Copyright (C) 2019 Gregory Nutt. All rights reserved.
|
||||||
|
*
|
||||||
|
* Ported by:
|
||||||
|
*
|
||||||
|
* Copyright (C) 2019 Pinecone Inc. All rights reserved.
|
||||||
|
* Author: lihaichen <li8303@163.com>
|
||||||
|
*
|
||||||
|
* This port derives from ARM mbed logic which has a compatible 3-clause
|
||||||
|
* BSD license:
|
||||||
|
*
|
||||||
|
* Copyright (c) 2017, Arm Limited. All rights reserved.
|
||||||
|
*
|
||||||
|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions
|
||||||
|
* are met:
|
||||||
|
*
|
||||||
|
* 1. Redistributions of source code must retain the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer.
|
||||||
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer in
|
||||||
|
* the documentation and/or other materials provided with the
|
||||||
|
* distribution.
|
||||||
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
||||||
|
* used to endorse or promote products derived from this software
|
||||||
|
* without specific prior written permission.
|
||||||
|
*
|
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||||
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||||
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||||||
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||||||
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||||
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||||||
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||||||
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||||||
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||||
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||||
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||||
|
* POSSIBILITY OF SUCH DAMAGE.
|
||||||
|
*
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Included Files
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
#include "lfs.h"
|
||||||
|
#include "lfs_util.h"
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Public Functions
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/* Only compile if user does not provide custom config */
|
||||||
|
|
||||||
|
#ifndef LFS_CONFIG
|
||||||
|
|
||||||
|
/* Software CRC implementation with small lookup table */
|
||||||
|
|
||||||
|
void lfs_crc(FAR uint32_t *restrict crc, FAR const void *buffer, size_t size)
|
||||||
|
{
|
||||||
|
static const uint32_t rtable[16] =
|
||||||
|
{
|
||||||
|
0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190, 0x6b6b51f4,
|
||||||
|
0x4db26158, 0x5005713c, 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
|
||||||
|
0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c,
|
||||||
|
};
|
||||||
|
|
||||||
|
FAR const uint8_t *data = buffer;
|
||||||
|
size_t i;
|
||||||
|
|
||||||
|
for (i = 0; i < size; i++)
|
||||||
|
{
|
||||||
|
*crc = (*crc >> 4) ^ rtable[(*crc ^ (data[i] >> 0)) & 0xf];
|
||||||
|
*crc = (*crc >> 4) ^ rtable[(*crc ^ (data[i] >> 4)) & 0xf];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif
|
||||||
@@ -0,0 +1,283 @@
|
|||||||
|
/****************************************************************************
|
||||||
|
* fs/littlefs/lfs.c
|
||||||
|
*
|
||||||
|
* This file is a part of NuttX:
|
||||||
|
*
|
||||||
|
* Copyright (C) 2019 Gregory Nutt. All rights reserved.
|
||||||
|
*
|
||||||
|
* Ported by:
|
||||||
|
*
|
||||||
|
* Copyright (C) 2019 Pinecone Inc. All rights reserved.
|
||||||
|
* Author: lihaichen <li8303@163.com>
|
||||||
|
*
|
||||||
|
* This port derives from ARM mbed logic which has a compatible 3-clause
|
||||||
|
* BSD license:
|
||||||
|
*
|
||||||
|
* Copyright (c) 2017, Arm Limited. All rights reserved.
|
||||||
|
*
|
||||||
|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions
|
||||||
|
* are met:
|
||||||
|
*
|
||||||
|
* 1. Redistributions of source code must retain the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer.
|
||||||
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
* notice, this list of conditions and the following disclaimer in
|
||||||
|
* the documentation and/or other materials provided with the
|
||||||
|
* distribution.
|
||||||
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
||||||
|
* used to endorse or promote products derived from this software
|
||||||
|
* without specific prior written permission.
|
||||||
|
*
|
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||||
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||||
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||||||
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||||||
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||||
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||||||
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||||||
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||||||
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||||
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||||
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||||
|
* POSSIBILITY OF SUCH DAMAGE.
|
||||||
|
*
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
#ifndef __FS_LITTLEFS_LFS_UTIL_H
|
||||||
|
#define __FS_LITTLEFS_LFS_UTIL_H
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Included Files
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/* Users can override lfs_util.h with their own configuration by defining
|
||||||
|
* LFS_CONFIG as a header file to include (-DLFS_CONFIG=lfs_config.h).
|
||||||
|
*
|
||||||
|
* If LFS_CONFIG is used, none of the default utils will be emitted and must be
|
||||||
|
* provided by the config file. To start I would suggest copying lfs_util.h and
|
||||||
|
* modifying as needed.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#ifdef LFS_CONFIG
|
||||||
|
# define LFS_STRINGIZE(x) LFS_STRINGIZE2(x)
|
||||||
|
# define LFS_STRINGIZE2(x) #x
|
||||||
|
# include LFS_STRINGIZE(LFS_CONFIG)
|
||||||
|
#else
|
||||||
|
|
||||||
|
/* System includes */
|
||||||
|
|
||||||
|
#include <stdint.h>
|
||||||
|
#include <stdbool.h>
|
||||||
|
#include <string.h>
|
||||||
|
|
||||||
|
#define LFS_NO_DEBUG
|
||||||
|
|
||||||
|
#ifndef LFS_NO_MALLOC
|
||||||
|
# include <stdlib.h>
|
||||||
|
#endif
|
||||||
|
#ifndef LFS_NO_ASSERT
|
||||||
|
# include <assert.h>
|
||||||
|
#endif
|
||||||
|
#if !defined(LFS_NO_DEBUG) || !defined(LFS_NO_WARN) || !defined(LFS_NO_ERROR)
|
||||||
|
# include <stdio.h>
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Pre-processor Definitions
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/* Macros, may be replaced by system specific wrappers. Arguments to these
|
||||||
|
* macros must not have side-effects as the macros can be removed for a smaller
|
||||||
|
* code footprint
|
||||||
|
*/
|
||||||
|
|
||||||
|
/* Logging functions */
|
||||||
|
|
||||||
|
#ifndef LFS_NO_DEBUG
|
||||||
|
# define LFS_DEBUG(fmt, ...) \
|
||||||
|
printf("lfs debug:%d: " fmt "\n", __LINE__, __VA_ARGS__)
|
||||||
|
#else
|
||||||
|
# define LFS_DEBUG(fmt, ...)
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#ifndef LFS_NO_WARN
|
||||||
|
# define LFS_WARN(fmt, ...) \
|
||||||
|
printf("lfs warn:%d: " fmt "\n", __LINE__, __VA_ARGS__)
|
||||||
|
#else
|
||||||
|
# define LFS_WARN(fmt, ...)
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#ifndef LFS_NO_ERROR
|
||||||
|
# define LFS_ERROR(fmt, ...) \
|
||||||
|
printf("lfs error:%d: " fmt "\n", __LINE__, __VA_ARGS__)
|
||||||
|
#else
|
||||||
|
# define LFS_ERROR(fmt, ...)
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/* Runtime assertions */
|
||||||
|
|
||||||
|
#ifndef LFS_NO_ASSERT
|
||||||
|
# define LFS_ASSERT(test) assert(test)
|
||||||
|
#else
|
||||||
|
# define LFS_ASSERT(test)
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Public Types
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Public Data
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
#ifdef __cplusplus
|
||||||
|
extern "C"
|
||||||
|
{
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Inline Functions
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/* Builtin functions, these may be replaced by more efficient
|
||||||
|
* toolchain-specific implementations. LFS_NO_INTRINSICS falls back to a more
|
||||||
|
* expensive basic C implementation for debugging purposes
|
||||||
|
*/
|
||||||
|
|
||||||
|
/* Min/max functions for unsigned 32-bit numbers */
|
||||||
|
|
||||||
|
static inline uint32_t lfs_max(uint32_t a, uint32_t b)
|
||||||
|
{
|
||||||
|
return (a > b) ? a : b;
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline uint32_t lfs_min(uint32_t a, uint32_t b)
|
||||||
|
{
|
||||||
|
return (a < b) ? a : b;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Find the next smallest power of 2 less than or equal to a */
|
||||||
|
|
||||||
|
static inline uint32_t lfs_npw2(uint32_t a)
|
||||||
|
{
|
||||||
|
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
|
||||||
|
return 32 - __builtin_clz(a - 1);
|
||||||
|
#else
|
||||||
|
uint32_t r = 0;
|
||||||
|
uint32_t s;
|
||||||
|
a -= 1;
|
||||||
|
s = (a > 0xffff) << 4;
|
||||||
|
a >>= s;
|
||||||
|
r |= s;
|
||||||
|
s = (a > 0xff) << 3;
|
||||||
|
a >>= s;
|
||||||
|
r |= s;
|
||||||
|
s = (a > 0xf) << 2;
|
||||||
|
a >>= s;
|
||||||
|
r |= s;
|
||||||
|
s = (a > 0x3) << 1;
|
||||||
|
a >>= s;
|
||||||
|
r |= s;
|
||||||
|
return (r | (a >> 1)) + 1;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Count the number of trailing binary zeros in a
|
||||||
|
* lfs_ctz(0) may be undefined
|
||||||
|
*/
|
||||||
|
|
||||||
|
static inline uint32_t lfs_ctz(uint32_t a)
|
||||||
|
{
|
||||||
|
#if !defined(LFS_NO_INTRINSICS) && defined(__GNUC__)
|
||||||
|
return __builtin_ctz(a);
|
||||||
|
#else
|
||||||
|
return lfs_npw2((a & -a) + 1) - 1;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Count the number of binary ones in a */
|
||||||
|
|
||||||
|
static inline uint32_t lfs_popc(uint32_t a)
|
||||||
|
{
|
||||||
|
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
|
||||||
|
return __builtin_popcount(a);
|
||||||
|
#else
|
||||||
|
a = a - ((a >> 1) & 0x55555555);
|
||||||
|
a = (a & 0x33333333) + ((a >> 2) & 0x33333333);
|
||||||
|
return (((a + (a >> 4)) & 0xf0f0f0f) * 0x1010101) >> 24;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Find the sequence comparison of a and b, this is the distance
|
||||||
|
* between a and b ignoring overflow
|
||||||
|
*/
|
||||||
|
|
||||||
|
static inline int lfs_scmp(uint32_t a, uint32_t b)
|
||||||
|
{
|
||||||
|
return (int)(unsigned)(a - b);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Convert from 32-bit little-endian to native order */
|
||||||
|
|
||||||
|
static inline uint32_t lfs_fromle32(uint32_t a)
|
||||||
|
{
|
||||||
|
#if !defined(LFS_NO_INTRINSICS) && \
|
||||||
|
((defined(BYTE_ORDER) && BYTE_ORDER == ORDER_LITTLE_ENDIAN) || \
|
||||||
|
(defined(__BYTE_ORDER) && __BYTE_ORDER == __ORDER_LITTLE_ENDIAN) || \
|
||||||
|
(defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
|
||||||
|
return a;
|
||||||
|
#elif !defined(LFS_NO_INTRINSICS) && \
|
||||||
|
((defined(BYTE_ORDER) && BYTE_ORDER == ORDER_BIG_ENDIAN) || \
|
||||||
|
(defined(__BYTE_ORDER) && __BYTE_ORDER == __ORDER_BIG_ENDIAN) || \
|
||||||
|
(defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))
|
||||||
|
return __builtin_bswap32(a);
|
||||||
|
#else
|
||||||
|
return (((uint8_t *)&a)[0] << 0) | (((uint8_t *)&a)[1] << 8) |
|
||||||
|
(((uint8_t *)&a)[2] << 16) | (((uint8_t *)&a)[3] << 24);
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Convert to 32-bit little-endian from native order */
|
||||||
|
|
||||||
|
static inline uint32_t lfs_tole32(uint32_t a)
|
||||||
|
{
|
||||||
|
return lfs_fromle32(a);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Allocate memory, only used if buffers are not provided to littlefs */
|
||||||
|
|
||||||
|
static inline void *lfs_malloc(size_t size)
|
||||||
|
{
|
||||||
|
#ifndef LFS_NO_MALLOC
|
||||||
|
return malloc(size);
|
||||||
|
#else
|
||||||
|
return NULL;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Deallocate memory, only used if buffers are not provided to littlefs */
|
||||||
|
|
||||||
|
static inline void lfs_free(FAR void *p)
|
||||||
|
{
|
||||||
|
#ifndef LFS_NO_MALLOC
|
||||||
|
free(p);
|
||||||
|
#else
|
||||||
|
(void)p;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
/****************************************************************************
|
||||||
|
* Public Function Prototypes
|
||||||
|
****************************************************************************/
|
||||||
|
|
||||||
|
/* Calculate CRC-32 with polynomial = 0x04c11db7 */
|
||||||
|
|
||||||
|
void lfs_crc(uint32_t *crc, const void *buffer, size_t size);
|
||||||
|
|
||||||
|
#ifdef __cplusplus
|
||||||
|
} /* extern "C" */
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#endif
|
||||||
|
#endif /* __FS_LITTLEFS_LFS_UTIL_H */
|
||||||
File diff suppressed because it is too large
Load Diff
@@ -114,6 +114,12 @@ FAR const char *fs_gettype(FAR struct statfs *statbuf)
|
|||||||
break;
|
break;
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
#ifdef CONFIG_FS_LITTLEFS
|
||||||
|
case LITTLEFS_SUPER_MAGIC:
|
||||||
|
fstype = "littlefs";
|
||||||
|
break;
|
||||||
|
#endif
|
||||||
|
|
||||||
#ifdef CONFIG_NFS
|
#ifdef CONFIG_NFS
|
||||||
case NFS_SUPER_MAGIC:
|
case NFS_SUPER_MAGIC:
|
||||||
fstype = "nfs";
|
fstype = "nfs";
|
||||||
|
|||||||
+8
-1
@@ -78,7 +78,7 @@
|
|||||||
|
|
||||||
/* These file systems require MTD drivers */
|
/* These file systems require MTD drivers */
|
||||||
|
|
||||||
#ifdef CONFIG_FS_SPIFFS
|
#if defined(CONFIG_FS_SPIFFS) || defined(CONFIG_FS_LITTLEFS)
|
||||||
# define MDFS_SUPPORT 1
|
# define MDFS_SUPPORT 1
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
@@ -140,11 +140,18 @@ static const struct fsmap_t g_bdfsmap[] =
|
|||||||
extern const struct mountpt_operations spiffs_operations;
|
extern const struct mountpt_operations spiffs_operations;
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
#ifdef CONFIG_FS_LITTLEFS
|
||||||
|
extern const struct mountpt_operations littlefs_operations;
|
||||||
|
#endif
|
||||||
|
|
||||||
static const struct fsmap_t g_mdfsmap[] =
|
static const struct fsmap_t g_mdfsmap[] =
|
||||||
{
|
{
|
||||||
#ifdef CONFIG_FS_SPIFFS
|
#ifdef CONFIG_FS_SPIFFS
|
||||||
{ "spiffs", &spiffs_operations },
|
{ "spiffs", &spiffs_operations },
|
||||||
#endif
|
#endif
|
||||||
|
#ifdef CONFIG_FS_LITTLEFS
|
||||||
|
{ "littlefs", &littlefs_operations },
|
||||||
|
#endif
|
||||||
};
|
};
|
||||||
#endif /* MDFS_SUPPORT */
|
#endif /* MDFS_SUPPORT */
|
||||||
|
|
||||||
|
|||||||
@@ -222,6 +222,29 @@ struct fs_hostfsdir_s
|
|||||||
|
|
||||||
#endif /* CONFIG_DISABLE_MOUNTPOINT */
|
#endif /* CONFIG_DISABLE_MOUNTPOINT */
|
||||||
|
|
||||||
|
#ifdef CONFIG_FS_LITTLEFS
|
||||||
|
typedef uint32_t _lfs_block_t;
|
||||||
|
typedef uint32_t _lfs_size_t;
|
||||||
|
typedef uint32_t _lfs_off_t;
|
||||||
|
|
||||||
|
typedef struct _lfs_dir
|
||||||
|
{
|
||||||
|
struct _lfs_dir *next;
|
||||||
|
_lfs_block_t pair[2];
|
||||||
|
_lfs_off_t off;
|
||||||
|
|
||||||
|
_lfs_block_t head[2];
|
||||||
|
_lfs_off_t pos;
|
||||||
|
|
||||||
|
struct _lfs_disk_dir
|
||||||
|
{
|
||||||
|
uint32_t rev;
|
||||||
|
_lfs_size_t size;
|
||||||
|
_lfs_block_t tail[2];
|
||||||
|
} d;
|
||||||
|
} _lfs_dir_t;
|
||||||
|
#endif
|
||||||
|
|
||||||
struct fs_dirent_s
|
struct fs_dirent_s
|
||||||
{
|
{
|
||||||
/* This is the node that was opened by opendir. The type of the inode
|
/* This is the node that was opened by opendir. The type of the inode
|
||||||
@@ -289,6 +312,9 @@ struct fs_dirent_s
|
|||||||
#ifdef CONFIG_FS_SPIFFS
|
#ifdef CONFIG_FS_SPIFFS
|
||||||
struct fs_spiffsdir_s spiffs;
|
struct fs_spiffsdir_s spiffs;
|
||||||
#endif
|
#endif
|
||||||
|
#ifdef CONFIG_FS_LITTLEFS
|
||||||
|
_lfs_dir_t littlefs;
|
||||||
|
#endif
|
||||||
#ifdef CONFIG_FS_UNIONFS
|
#ifdef CONFIG_FS_UNIONFS
|
||||||
struct fs_unionfsdir_s unionfs;
|
struct fs_unionfsdir_s unionfs;
|
||||||
#endif
|
#endif
|
||||||
|
|||||||
@@ -96,6 +96,7 @@
|
|||||||
#define XFS_SUPER_MAGIC 0x58465342
|
#define XFS_SUPER_MAGIC 0x58465342
|
||||||
#define _XIAFS_SUPER_MAGIC 0x012fd16d
|
#define _XIAFS_SUPER_MAGIC 0x012fd16d
|
||||||
#define SPIFFS_SUPER_MAGIC 0x20090315
|
#define SPIFFS_SUPER_MAGIC 0x20090315
|
||||||
|
#define LITTLEFS_SUPER_MAGIC 0x0a732923
|
||||||
|
|
||||||
/* NuttX specific file-systems */
|
/* NuttX specific file-systems */
|
||||||
|
|
||||||
|
|||||||
Reference in New Issue
Block a user