Github/littlefs
1
Fork 0
Code Actions Activity

Extended lfsr_mount to accept mount flags

Browse Source 
This has been a long-time coming, mount flags are just too useful for
configuring a filesystem at runtime.

Currently this is limited to LFS_M_RDONLY and LFS_M_CKPROGS, but there
are a few more planned in the future:

  LFS_M_RDWR     = 0x0000, // Mount the filesystem as read and write
  LFS_M_RDONLY   = 0x0001, // Mount the filesystem as readonly
  LFS_M_STRICT*  = 0x0002, // Error if on-disk config does not match
  LFS_M_FORCE*   = 0x0004, // Ignore compat flags, mount readonly
  LFS_M_FORCEWITHRECKLESSABANDON*
                 = 0x0008, // Ignore compat flags, mount read write

  LFS_M_CKPROGS  = 0x0010, // Check progs by reading back progged data
  LFS_M_CKREADS* = 0x0020, // Check reads via checksums

  * Hypothetical

As a convenience, we also return mount flags in the struct lfs_fsinfo's
flags field as their relevant LFS_I_* variants. Though only to match
statvfs, and only because it's cheap, littlefs's API is low-level and we
should expect users to know what flags they passed to lfsr_mount.

As for the new mount flags:

- LFS_M_RDONLY - For consistency with existing APIs, this just asserts
  on write operations, which makes it a bit useless... But the info flag
  LFS_I_RDONLY may be useful for falling back to a readonly mode if
  we encounter on-disk compat issues.

  At least if implement the theoretical LFS_UNTRUSTED_USER mode
  LFS_M_RDONLY could become a runtime error.

- LFS_M_RDWR - This really just exists to compliment LFS_M_RDONLY and to
  match LFS_O_RDONLY/LFS_O_RDWR. It's just an alias for 0, and I don't
  think there will ever be a reason to make it non-0 (but I can always
  be wrong!).

- LFS_M_CKPROGS - This replaces the check_progs config option and avoids
  using a full byte to store a bool.

  We should probably also have a compile-time option to compile this out
  (LFS_NO_CKPROGS?), but that's a future thing to do.

This ended up adding a surprising bit of code, considering we're just
moving flags around, and noise in lfs_alloc added a bit of stack again:

           code          stack
  before: 35880           2672
  after:  35932 (+0.1%)   2680 (+0.3%)
This commit is contained in:
Christopher Haster
2024-07-15 01:48:37 -05:00
parent 0a3cb2dd3a
commit acfae9e072
25 changed files with 1322 additions and 1126 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/test_fsync.toml
+30 -30
View File
@@ -7,7 +7,7 @@ after = 'test_fwrite'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - reader kept open, recvs updates from a
@@ -108,7 +108,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -228,7 +228,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -362,7 +362,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -498,7 +498,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -549,7 +549,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = SEED;
@@ -612,7 +612,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -703,7 +703,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -804,7 +804,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -890,7 +890,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -981,7 +981,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -1084,7 +1084,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -1196,7 +1196,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -1298,7 +1298,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -1411,7 +1411,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint32_t prng = 42;
uint8_t between[RW][SIZE];
@@ -1546,7 +1546,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint32_t prng = 42;
uint8_t between[RW][SIZE];
@@ -1714,7 +1714,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - reader kept open, recvs updates from a
@@ -1801,7 +1801,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - reader kept open, recvs updates from a
@@ -1881,7 +1881,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -2002,7 +2002,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -2104,7 +2104,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - reader kept open, recvs updates from a
@@ -2206,7 +2206,7 @@ code = '''
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// a - writer
// b - writer
@@ -2352,7 +2352,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2448,7 +2448,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2554,7 +2554,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2642,7 +2642,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2740,7 +2740,7 @@ defines.CHUNK = '(SIZE+16-1) / 16'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2851,7 +2851,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
// create a file
uint32_t prng = 42;
@@ -2969,7 +2969,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint32_t prng = 42;
uint8_t between[RW][SIZE];
@@ -3119,7 +3119,7 @@ fuzz = 'SEED'
code = '''
lfs_t lfs;
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint32_t prng = 42;
uint8_t between[RW][SIZE];