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R0.15a

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Nov 22, 2024

Fixed a complie error when FF_FS_LOCK != 0. (appeared at R0.15)

Fixed a potential issue when work FatFs concurrency with FF_FS_REENTRANT, FF_VOLUMES >= 2 and FF_FS_LOCK > 0.

Made f_setlabel accept a volume label with Unix style volume ID when FF_STR_VOLUME_ID == 2.

Made FatFs update PercInUse field in exFAT VBR. (A preceding f_getfree is needed for the accuracy)
This commit is contained in:
Christopher Williams
2024-11-25 16:44:32 -07:00
parent b11f089319
commit 44b3c38b23
59 changed files with 940 additions and 939 deletions
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documents/doc/mkfs.html
+11 -12
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@@ -3,8 +3,6 @@
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mkfs.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mkfs</title>
</head>
@@ -36,12 +34,12 @@ FRESULT f_mkfs (
<dd>Specifies a combination of FAT type flags, <tt>FM_FAT</tt>, <tt>FM_FAT32</tt>, <tt>FM_EXFAT</tt> and bitwise-or of these three, <tt>FM_ANY</tt>. <tt>FM_EXFAT</tt> is ignored when exFAT is not enabled. These flags specify which type of FAT volume to be created. If two or more types are specified, one out of them will be selected depends on the volume size and <tt class="arg">au_size</tt>. The flag <tt>FM_SFD</tt> specifies to create the volume on the drive in SFD format. The default value is <tt>FM_ANY</tt>.</dd>
<dt>BYTE n_fat</dt>
<dd>Specifies number of FAT copies on the FAT/FAT32 volume. Valid value for this member is 1 or 2. The default value (0) and any invaid value gives 1. If the FAT type is exFAT, this member has no effect.</dd>
<dt>UINT n_align</dt>
<dd>Specifies alignment of the volume data area (file allocation pool, usually erase block boundary of flash memory media) in unit of sector. The valid value for this member is between 1 and 32768 inclusive in power of 2. If a zero (the default value) or any invalid value is given, the function obtains the block size from lower layer with <tt>disk_ioctl</tt> function.</dd>
<dt>DWORD au_size</dt>
<dd>Specifies size of the allocation unit (cluter) in unit of byte. The valid value is power of 2 between sector size and 128 * sector size inclusive for FAT/FAT32 volume, or up to 16 MB for exFAT volume. If a zero (default value) or any invalid value is given, the function uses default allocation unit size depends on the volume size.</dd>
<dt>UINT align</dt>
<dd>Specifies alignment of the volume data area (file allocation pool, usually erase block boundary of flash memory media) <em>in unit of sector</em>. The valid value for this member is between 1 and 32768 inclusive in power of 2. If a zero (the default value) or any invalid value is given, the function obtains the block size from lower layer with <tt>disk_ioctl</tt> function.</dd>
<dt>UINT n_root</dt>
<dd>Specifies number of root directory entries on the FAT volume. Valid value for this member is up to 32768 and aligned to sector size / 32. The default value (0) and any invaid value gives 512. If the FAT type is FAT32 or exFAT, this member has no effect.</dd>
<dt>DWORD au_size</dt>
<dd>Specifies size of the cluster (allocation unit) <em>in unit of byte</em>. The valid value for this member is between sector size and 128 * sector size inclusive in power of 2 for FAT/FAT32 volume and up to 16 MB in power of 2 for exFAT volume. If a zero (default value) or any invalid value is given, the function uses a default cluster size depends on the volume size.</dd>
</dl>
<dt>work</dt>
<dd>Pointer to the working buffer used for the format process. If a null pointer is given with <tt><a href="config.html#use_lfn">FF_USE_LFN</a> == 3</tt>, the function uses a <tt>len</tt> bytes of heap memory in this function.</dd>
@@ -69,7 +67,7 @@ FRESULT f_mkfs (
<p>The FAT sub-type, FAT12/FAT16/FAT32, of FAT volume except exFAT is determined by only number of clusters on the volume and nothing else, according to the FAT specification issued by Microsoft. Thus the FAT sub-type of created volume depends on the volume size and the cluster size. In case of the combination of FAT type and cluter size specified by argument is not valid for the volume size, the function will fail with <tt>FR_MKFS_ABORTED</tt>.</p>
<p>The allocation unit, also known as <em>cluster</em>, is a unit of disk space allocation for files. When the size of allocation unit is 32768 bytes, a file with 100 bytes in size occupies 32768 bytes of disk space. The space efficiency of disk usage gets worse as increasing size of allocation unit, but, on the other hand, the read/write performance increases. Therefore the size of allocation unit is a trade-off between space efficiency and performance. For the large volumes in GB order, 32768 bytes or larger, automatically selected by default, is recommended for most case unless extremely many small files are created in the volume.</p>
<p>When the logical drive to be formatted is associated with a physical drive (<tt><a href="config.html#multi_partition">FF_MULTI_PARTITION</a> == 0</tt> or <tt>VolToPart[].pt == 0</tt>) and <tt>FM_SFD</tt> flag is not specified, a partition occupies entire drive space is created and then the FAT volume is created in the partition. When <tt>FM_SFD</tt> flag is specified, the FAT volume is created without any disk partitioning.</p>
<p>When the logical drive to be formatted is associated with a specific partition by multiple partition feature (<tt>FF_MULTI_PARTITION == 1</tt> and <tt>VolToPart[].pt &gt; 0</tt>), the FAT volume is created in the partition of the physical drive specified by <a href="filename.html#vol">volume mapping table</a> and <tt>FM_SFD</tt> flag is ignored. The hosting physical drive needs to be partitioned with <tt>f_fdisk</tt> function or any partitioning tool prior to create the FAT volume with this function. If the partition is not exist, the function aborts with <tt>FR_MKFS_ABORTED</tt>.</p>
<p>When the logical drive to be formatted is associated with a specific partition by multiple partition feature (<tt>FF_MULTI_PARTITION == 1</tt> and <tt>VolToPart[].pt &gt; 0</tt>), the FAT volume is created in the partition of the physical drive specified by <a href="filename.html#vol">volume mapping table</a> and <tt>FM_SFD</tt> flag is ignored. The hosting physical drive needs to be partitioned with <tt>f_fdisk</tt> function or some partitioning tool prior to create the FAT volume with this function. If the partition is not exist, the function fails with <tt>FR_MKFS_ABORTED</tt>.</p>
<p>There are three standard disk partitioning formats, MBR, GPT and SFD. The MBR format, also known as FDISK format, is usually used for harddisk, memory card and U disk. It can divide a physical drive into one or more partitions with a partition table. The GPT, GUID Partition Table, is a newly defined patitioning format for large storage devices. FatFs suppors the GPT only when 64-bit LBA is enabled. The SFD, Super-Floppy Disk, is non-partitioned disk format. The FAT volume is located at LBA 0 and occupies the entire physical drive without any disk partitioning. It is usually used for floppy disk, optical disk and most super-floppy media. Some combination of systems and media support only either partitioned format or non-partitioned format and the other is not supported.</p>
<p>Some systems manage the partitions in the on-board storage in non-standard format. The partitions are mapped as physical drives identified by <tt class="arg">pdrv</tt> in <tt>disk_*</tt> functions. For such systems, SFD format is suitable to create the FAT volume in the partition.</p>
</div>
@@ -97,21 +95,21 @@ int main (void)
if (res) ...
<span class="c">/* Give a work area to the default drive */</span>
f_mount(&amp;fs, "", 0);
<em>f_mount</em>(&amp;fs, "", 0);
<span class="c">/* Create a file as new */</span>
res = f_open(&amp;fil, "hello.txt", FA_CREATE_NEW | FA_WRITE);
res = <em>f_open</em>(&amp;fil, "hello.txt", FA_CREATE_NEW | FA_WRITE);
if (res) ...
<span class="c">/* Write a message */</span>
f_write(&amp;fil, "Hello, World!\r\n", 15, &amp;bw);
<em>f_write</em>(&amp;fil, "Hello, World!\r\n", 15, &amp;bw);
if (bw != 15) ...
<span class="c">/* Close the file */</span>
f_close(&amp;fil);
<em>f_close</em>(&amp;fil);
<span class="c">/* Unregister work area */</span>
f_mount(0, "", 0);
<em>f_mount</em>(0, "", 0);
...
</pre>
@@ -122,6 +120,7 @@ int main (void)
<p><a href="../res/mkfs.xlsx">Example of volume size and format parameters</a>, <a href="filename.html#vol">Volume management</a>, <tt><a href="fdisk.html">f_fdisk</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>