From patchwork Thu Jul 19 22:03:06 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Beno=C3=AEt_Th=C3=A9baudeau?= X-Patchwork-Id: 172092 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from theia.denx.de (theia.denx.de [85.214.87.163]) by ozlabs.org (Postfix) with ESMTP id CD8F62C02AD for ; Fri, 20 Jul 2012 07:58:18 +1000 (EST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 40E8A280D6; Thu, 19 Jul 2012 23:58:17 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9cPkpDz7J514; Thu, 19 Jul 2012 23:58:17 +0200 (CEST) Received: from theia.denx.de (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 72AB1280C3; Thu, 19 Jul 2012 23:58:15 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id D52EA280B8 for ; Thu, 19 Jul 2012 23:58:11 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id GHxmmju3CJkd for ; Thu, 19 Jul 2012 23:58:10 +0200 (CEST) X-policyd-weight: NOT_IN_SBL_XBL_SPAMHAUS=-1.5 NOT_IN_SPAMCOP=-1.5 NOT_IN_BL_NJABL=-1.5 (only DNSBL check requested) Received: from zose-mta12.web4all.fr (zose-mta12.web4all.fr [178.33.204.89]) by theia.denx.de (Postfix) with ESMTP id 3724F280D1 for ; Thu, 19 Jul 2012 23:58:10 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by zose-mta12.web4all.fr (Postfix) with ESMTP id 18D91904F0; Fri, 20 Jul 2012 00:00:38 +0200 (CEST) X-Virus-Scanned: amavisd-new at zose1.web4all.fr Received: from zose-mta12.web4all.fr ([127.0.0.1]) by localhost (zose-mta12.web4all.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id aMLD+1YOBNDl; Fri, 20 Jul 2012 00:00:37 +0200 (CEST) Received: from zose-store12.web4all.fr (zose-store12.web4all.fr [178.33.204.49]) by zose-mta12.web4all.fr (Postfix) with ESMTP id 8772D904EF; Fri, 20 Jul 2012 00:00:37 +0200 (CEST) Date: Fri, 20 Jul 2012 00:03:06 +0200 (CEST) From: =?utf-8?Q?Beno=C3=AEt_Th=C3=A9baudeau?= To: u-boot@lists.denx.de Message-ID: <895920526.294134.1342735386480.JavaMail.root@advansee.com> MIME-Version: 1.0 X-Originating-IP: [88.188.188.98] X-Mailer: Zimbra 7.2.0_GA_2669 (ZimbraWebClient - FF3.0 (Win)/7.2.0_GA_2669) Subject: [U-Boot] [PATCH 7/7] FAT: Make it possible to read from any file position X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.11 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: u-boot-bounces@lists.denx.de Errors-To: u-boot-bounces@lists.denx.de When storage devices contain files larger than the embedded RAM, it is useful to be able to read these files by chunks, e.g. for a software update to the embedded NAND Flash from an external storage device (USB stick, SD card, etc.). Hence, this patch makes it possible by adding a new FAT API to read files from a given position. Signed-off-by: Benoît Thébaudeau Cc: Wolfgang Denk --- .../fs/fat/fat.c | 90 ++++++++++++++++---- 1 file changed, 72 insertions(+), 18 deletions(-) diff --git u-boot-66714b1.orig/fs/fat/fat.c u-boot-66714b1/fs/fat/fat.c index 8ac8b85..709a5eb 100644 --- u-boot-66714b1.orig/fs/fat/fat.c +++ u-boot-66714b1/fs/fat/fat.c @@ -329,13 +329,16 @@ get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer, } /* - * Read at most 'maxsize' bytes from the file associated with 'dentptr' + * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr' * into 'buffer'. * Return the number of bytes read or -1 on fatal errors. */ +__u8 get_contents_vfatname_block[MAX_CLUSTSIZE] + __aligned(ARCH_DMA_MINALIGN); + static long -get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer, - unsigned long maxsize) +get_contents (fsdata *mydata, dir_entry *dentptr, unsigned long pos, + __u8 *buffer, unsigned long maxsize) { unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0; unsigned int bytesperclust = mydata->clust_size * mydata->sect_size; @@ -345,12 +348,59 @@ get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer, debug("Filesize: %ld bytes\n", filesize); - if (maxsize > 0 && filesize > maxsize) - filesize = maxsize; + if (pos >= filesize) { + debug("Read position past EOF: %lu\n", pos); + return gotsize; + } + + if (maxsize > 0 && filesize > pos + maxsize) + filesize = pos + maxsize; debug("%ld bytes\n", filesize); actsize = bytesperclust; + + /* go to cluster at pos */ + while (actsize <= pos) { + curclust = get_fatent(mydata, curclust); + if (CHECK_CLUST(curclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return gotsize; + } + actsize += bytesperclust; + } + + /* actsize > pos */ + actsize -= bytesperclust; + filesize -= actsize; + pos -= actsize; + + /* align to beginning of next cluster if any */ + if (pos) { + actsize = min(filesize, bytesperclust); + if (get_cluster(mydata, curclust, get_contents_vfatname_block, + (int)actsize) != 0) { + printf("Error reading cluster\n"); + return -1; + } + filesize -= actsize; + actsize -= pos; + memcpy(buffer, get_contents_vfatname_block + pos, actsize); + gotsize += actsize; + if (!filesize) + return gotsize; + buffer += actsize; + + curclust = get_fatent(mydata, curclust); + if (CHECK_CLUST(curclust, mydata->fatsize)) { + debug("curclust: 0x%x\n", curclust); + debug("Invalid FAT entry\n"); + return gotsize; + } + } + + actsize = bytesperclust; endclust = curclust; do { @@ -434,9 +484,6 @@ static int slot2str (dir_slot *slotptr, char *l_name, int *idx) * into 'retdent' * Return 0 on success, -1 otherwise. */ -__u8 get_vfatname_block[MAX_CLUSTSIZE] - __aligned(ARCH_DMA_MINALIGN); - static int get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, dir_entry *retdent, char *l_name) @@ -475,13 +522,13 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, return -1; } - if (get_cluster(mydata, curclust, get_vfatname_block, + if (get_cluster(mydata, curclust, get_contents_vfatname_block, mydata->clust_size * mydata->sect_size) != 0) { debug("Error: reading directory block\n"); return -1; } - slotptr2 = (dir_slot *)get_vfatname_block; + slotptr2 = (dir_slot *)get_contents_vfatname_block; while (counter > 0) { if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter) @@ -492,7 +539,7 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, /* Save the real directory entry */ realdent = (dir_entry *)slotptr2; - while ((__u8 *)slotptr2 > get_vfatname_block) { + while ((__u8 *)slotptr2 > get_contents_vfatname_block) { slotptr2--; slot2str(slotptr2, l_name, &idx); } @@ -771,12 +818,12 @@ exit: return ret; } -__u8 do_fat_read_block[MAX_CLUSTSIZE] +__u8 do_fat_read_at_block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); long -do_fat_read (const char *filename, void *buffer, unsigned long maxsize, - int dols) +do_fat_read_at (const char *filename, unsigned long pos, void *buffer, + unsigned long maxsize, int dols) { char fnamecopy[2048]; boot_sector bs; @@ -890,12 +937,12 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, (mydata->fatsize == 32) ? (mydata->clust_size) : PREFETCH_BLOCKS, - do_fat_read_block) < 0) { + do_fat_read_at_block) < 0) { debug("Error: reading rootdir block\n"); goto exit; } - dentptr = (dir_entry *) do_fat_read_block; + dentptr = (dir_entry *) do_fat_read_at_block; } for (i = 0; i < DIRENTSPERBLOCK; i++) { @@ -915,7 +962,7 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, get_vfatname(mydata, root_cluster, - do_fat_read_block, + do_fat_read_at_block, dentptr, l_name); if (dols == LS_ROOT) { @@ -1118,7 +1165,7 @@ rootdir_done: subname = nextname; } - ret = get_contents(mydata, dentptr, buffer, maxsize); + ret = get_contents(mydata, dentptr, pos, buffer, maxsize); debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret); exit: @@ -1126,6 +1173,13 @@ exit: return ret; } +long +do_fat_read (const char *filename, void *buffer, unsigned long maxsize, + int dols) +{ + return do_fat_read_at(filename, 0, buffer, maxsize, dols); +} + int file_fat_detectfs (void) { boot_sector bs;