From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-we0-f177.google.com ([74.125.82.177]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TE5hs-0004tk-Dp for barebox@lists.infradead.org; Tue, 18 Sep 2012 21:51:49 +0000 Received: by weyr3 with SMTP id r3so196164wey.36 for ; Tue, 18 Sep 2012 14:51:46 -0700 (PDT) From: Franck Jullien Date: Tue, 18 Sep 2012 23:51:36 +0200 Message-Id: <1348005096-3419-2-git-send-email-franck.jullien@gmail.com> In-Reply-To: <1348005096-3419-1-git-send-email-franck.jullien@gmail.com> References: <1348005096-3419-1-git-send-email-franck.jullien@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 2/2] [v2] fs/fat: Handle MBR on the first sector To: barebox@lists.infradead.org Use filetype to detect FAT boot sector. Add support for disk with MBR on the first sector. Signed-off-by: Franck Jullien --- fs/fat/ff.c | 37 +++++++++++++++++++------------------ 1 files changed, 19 insertions(+), 18 deletions(-) diff --git a/fs/fat/ff.c b/fs/fat/ff.c index 66db1d6..33f8b61 100644 --- a/fs/fat/ff.c +++ b/fs/fat/ff.c @@ -93,6 +93,7 @@ #include #include #include +#include #include "ff.h" /* FatFs configurations and declarations */ #include "diskio.h" /* Declarations of low level disk I/O functions */ @@ -1531,29 +1532,20 @@ int follow_path ( /* 0(0): successful, !=0: error code */ /* * Load boot record and check if it is an FAT boot record */ -static int check_fs ( /* 0:The FAT BR, 1:Valid BR but not an FAT, 2:Not a BR, 3:Disk error */ +static enum filetype check_fs ( /* 0:The FAT BR, 1:Valid BR but not an FAT, 2:Not a BR, 3:Disk error */ FATFS *fs, /* File system object */ - DWORD sect /* Sector# (lba) to check if it is an FAT boot record or not */ + DWORD sect, /* Sector# (lba) to check if it is an FAT boot record or not */ + DWORD *bootsec ) { - int ret; + enum filetype ret; /* Load boot record */ ret = disk_read(fs, fs->win, sect, 1); if (ret) - return ret; - /* Check record signature (always placed at offset 510 even if the sector size is>512) */ - if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55) - return -ENODEV; - - /* Check "FAT" string */ - if ((LD_DWORD(&fs->win[BS_FilSysType]) & 0xFFFFFF) == 0x544146) - return 0; - - if ((LD_DWORD(&fs->win[BS_FilSysType32]) & 0xFFFFFF) == 0x544146) - return 0; + return filetype_unknown; - return -ENODEV; + return is_fat_or_mbr(fs->win, bootsec); } /* @@ -1565,8 +1557,10 @@ static int chk_mounted ( /* 0(0): successful, !=0: any error occurred */ ) { BYTE fmt, b; + DWORD first_boot_sect; DWORD bsect, fasize, tsect, sysect, nclst, szbfat; WORD nrsv; + enum filetype type; INIT_LIST_HEAD(&fs->dirtylist); @@ -1579,9 +1573,16 @@ static int chk_mounted ( /* 0(0): successful, !=0: any error occurred */ return -EIO; #endif /* Search FAT partition on the drive. Supports only generic partitionings, FDISK and SFD. */ - fmt = check_fs(fs, bsect = 0); /* Check sector 0 if it is a VBR */ - if (fmt) - return fmt; /* No FAT volume is found */ + type = check_fs(fs, bsect = 0, &first_boot_sect); /* Check sector 0 if it is a VBR */ + if (type == filetype_mbr) { + /* Sector 0 is an MBR, now check for FAT in the first partition */ + type = check_fs(fs, bsect = first_boot_sect, NULL); + if (type != filetype_fat) + return -ENODEV; + } + + if (type == filetype_unknown) + return -ENODEV; /* Following code initializes the file system object */ -- 1.7.1 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox