diff options
| -rw-r--r-- | fs/fat/fat.c | 1 | ||||
| -rw-r--r-- | fs/fat/fat_write.c | 31 | ||||
| -rw-r--r-- | include/fat.h | 1 |
3 files changed, 21 insertions, 12 deletions
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index 826bd85..df9f2b5 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -876,6 +876,7 @@ int do_fat_read_at(const char *filename, loff_t pos, void *buffer, } mydata->fatbufnum = -1; + mydata->fat_dirty = 0; mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE); if (mydata->fatbuf == NULL) { debug("Error: allocating memory\n"); diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 961ccd8..babe9c8 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -104,13 +104,19 @@ static __u8 num_of_fats; /* * Write fat buffer into block device */ -static int flush_fat_buffer(fsdata *mydata) +static int flush_dirty_fat_buffer(fsdata *mydata) { int getsize = FATBUFBLOCKS; __u32 fatlength = mydata->fatlength; __u8 *bufptr = mydata->fatbuf; __u32 startblock = mydata->fatbufnum * FATBUFBLOCKS; + debug("debug: evicting %d, dirty: %d\n", mydata->fatbufnum, + (int)mydata->fat_dirty); + + if ((!mydata->fat_dirty) || (mydata->fatbufnum == -1)) + return 0; + startblock += mydata->fat_sect; if (getsize > fatlength) @@ -130,6 +136,7 @@ static int flush_fat_buffer(fsdata *mydata) return -1; } } + mydata->fat_dirty = 0; return 0; } @@ -186,10 +193,8 @@ static __u32 get_fatent_value(fsdata *mydata, __u32 entry) startblock += mydata->fat_sect; /* Offset from start of disk */ /* Write back the fatbuf to the disk */ - if (mydata->fatbufnum != -1) { - if (flush_fat_buffer(mydata) < 0) - return -1; - } + if (flush_dirty_fat_buffer(mydata) < 0) + return -1; if (disk_read(startblock, getsize, bufptr) < 0) { debug("Error reading FAT blocks\n"); @@ -494,10 +499,8 @@ static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value) if (getsize > fatlength) getsize = fatlength; - if (mydata->fatbufnum != -1) { - if (flush_fat_buffer(mydata) < 0) - return -1; - } + if (flush_dirty_fat_buffer(mydata) < 0) + return -1; if (disk_read(startblock, getsize, bufptr) < 0) { debug("Error reading FAT blocks\n"); @@ -506,6 +509,9 @@ static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value) mydata->fatbufnum = bufnum; } + /* Mark as dirty */ + mydata->fat_dirty = 1; + /* Set the actual entry */ switch (mydata->fatsize) { case 32: @@ -645,7 +651,7 @@ static void flush_dir_table(fsdata *mydata, dir_entry **dentptr) dir_curclust = dir_newclust; - if (flush_fat_buffer(mydata) < 0) + if (flush_dirty_fat_buffer(mydata) < 0) return; memset(get_dentfromdir_block, 0x00, @@ -675,7 +681,7 @@ static int clear_fatent(fsdata *mydata, __u32 entry) } /* Flush fat buffer */ - if (flush_fat_buffer(mydata) < 0) + if (flush_dirty_fat_buffer(mydata) < 0) return -1; return 0; @@ -1011,6 +1017,7 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size, } mydata->fatbufnum = -1; + mydata->fat_dirty = 0; mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE); if (mydata->fatbuf == NULL) { debug("Error: allocating memory\n"); @@ -1111,7 +1118,7 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size, debug("attempt to write 0x%llx bytes\n", *actwrite); /* Flush fat buffer */ - ret = flush_fat_buffer(mydata); + ret = flush_dirty_fat_buffer(mydata); if (ret) { printf("Error: flush fat buffer\n"); goto exit; diff --git a/include/fat.h b/include/fat.h index 9d053e6..8ec91cd 100644 --- a/include/fat.h +++ b/include/fat.h @@ -169,6 +169,7 @@ typedef struct { int fatsize; /* Size of FAT in bits */ __u32 fatlength; /* Length of FAT in sectors */ __u16 fat_sect; /* Starting sector of the FAT */ + __u8 fat_dirty; /* Set if fatbuf has been modified */ __u32 rootdir_sect; /* Start sector of root directory */ __u16 sect_size; /* Size of sectors in bytes */ __u16 clust_size; /* Size of clusters in sectors */ |