Changes between Version 3 and Version 4 of file_system

Timestamp:

May 27, 2015, 10:04:17 AM (10 years ago)

Author:

alain

Comment:

--

file_system

@@ -9 +9 @@
 This implementation supports only block devices with block_size = 512 bytes.
 
+The max file size is 4 Gbytes.
+ 
 In the context of the FAT32, a cluster is the smallest storage allocation unit on the block device : any file  (or directory) occupies at least one cluster, and one cluster cannot be shared by 2 different files.
 
@@ -48 +50 @@
 
 == 4) Block Device Drivers ==
+
+To support varions block device peripheral, this FAT32 implementation defines a generic _fat_ioc_access() function to access the physical block device defined in the target architecture. This function transfer one or several blocks between the block device and the file_cache by calling the relevant driver.
+
+=== int '''_fat_ioc_access'''( unsigned int use_irq ,  unsigned int to_mem ,  unsigned int lba , unsigned int buf_vaddr , unsigned int count ) ===
+ * '''use_irq''' : boolean (RX transfer if non zero)
+ * '''to_mem''' : boolean (from block device to memory if non zero) 
+ * '''lba''' : logical block address on block device
+ * '''buf_vaddr''' : memory buffer virtual address
+ * ''' count''' : number of blocks to be transfered