From: chessmylitis@hotmail.com To: manningc2@actrix.gen.nz; yaffs@lists.aleph1.co.uk Subject: RE: [Yaffs] (no subject) Date: Thu, 9 Jun 2011 14:39:45 +0000 > From: manningc2@actrix.gen.nz > To: yaffs@lists.aleph1.co.uk > Subject: Re: [Yaffs] (no subject) > Date: Thu, 9 Jun 2011 06:23:38 +1200 > CC: chessmylitis@hotmail.com > > On Wednesday 08 June 2011 18:51:36 Rhykie Rhykie wrote: > > From: chessmylitis@hotmail.com > > To: manningc2@actrix.gen.nz > > Subject: RE: [Yaffs] (no subject) > > Date: Wed, 8 Jun 2011 06:47:08 +0000 > > > > > From: manningc2@actrix.gen.nz > > > To: yaffs@lists.aleph1.co.uk > > > Subject: Re: [Yaffs] (no subject) > > > Date: Wed, 8 Jun 2011 17:01:01 +1200 > > > CC: chessmylitis@hotmail.com > > > > > > On Wednesday 08 June 2011 02:10:42 Rhykie Rhykie wrote: > > > > Hi, > > > > I have two questions: > > > > > > > > 1) In the cramfs file system i have a source code in which i want to > > > > use fread()/fwrite() functions to read/write to a text file in the > > > > yaffs file system, all this in a nand flash memory in two different > > > > partitions. Unfortunately when compiling i get the "trying to access > > > > read-only file system" error. Any idea of how i can achieve what i want > > > > to do. > > > > > > That is very little info to work on/ Can you explain more? > > > > Ok, the nand flash is divided into four MTD block partitions; in mtdblock2 > > there is a cramfs file system which comprises my source code. Now since > > cramfs is read-only, I want to permanently store some text files in > > mtdblock3 which is a yaffs file system, allowing read and write. Then from > > the cramfs[mtdblock2] I want to access those files in [yaffs]mtdblock3 to > > perform read/write. For example I have the following instruction, in my > > source code [mtdblock2], to open the file in mtdblock3: FILE*ft = > > fopen("/dev/mtdblock3/myfile.txt", "r+"); So I get I get the error! If the > > file myfile.txt is in mtdblock3 yaffs partition, is its directory written > > as: /dev/mtdblock3/myfile.txt? > > I am curious about the file names. Are those you are really using? > It does not look like you have mounted the yaffs partition. Once you have > mounted the partition, the files become available at the mount pooint, not on > the partition. > > When you type "mount" on a console, what do you get? When typing mount on a console, just after boot-up, I get the following: rootfs on / type rootfs (rw) /dev/root on / type cramfs (ro) proc on /proc type proc (rw) none on /tmp type ramfs (rw) mdev on /dev type ramfs (rw) sysfs on /sys type sysfs (rw) which shows that mtdblock3 is not mounted I then typed: $mount -t yaffs /dev/mtdblock3 /mnt/, followed by: $mount This is what I got: /dev/root on / type cramfs (ro) proc on /proc type proc (rw) none on /tmp type ramfs (rw) mdev on /dev type ramfs (rw) sysfs on /sys type sysfs (rw) /dev/mtdblock3 on /mnt type yaffs (rw) which shows that mtdblock3 is NOW mounted! Now in the yaffs mount point /mnt, I have a file myfile.txt which I want to read and write from within the cramfs file system. So I now see that I can open the file by using the instruction: fopen("/mnt/myfile.txt", "r+"); The problem now is that I want mtdblock3 to be mounted automatically during boot-up, I included the following instruction in the /etc/fstab file: /dev/mtdblock3 /mnt/ yaffs defaults 0 0 But during boot-up I get the following error message: mount: mounting mtdblock3 on /mnt/ failed: No such file or directory The /dev/mtdblock3 and /mnt directories exist!!!! I even issued the following instruction in the /etc/init.d/rcS file but couldnt get any help!!!: /bin/mount -t yaffs /dev/mtdblock3 /mnt/ Any idea of how I can solve the problem? > > > > > > > > > 2)When the cramfs file system is configured to be the root after kernel > > > > boot-up, i have read that i can mount the yaffs to mtdblock3 partition > > > > by using the command mount -t yaffs /dev/mtdblock3 /mnt/. > > > > > > > > In the /mnt directory, i get the empty yaffs folder. As i was > > > > researching about how to get going with yaffs i got a couple yaffs > > > > source code which i dont know how to use them. Please help, how do i > > > > get a yaffs file system in the nand partition. > > > > > > First, start off with an empty flash (before you mouint yaffs). You can > > > use flash_eraseall to do this. Mount yaffs, then copy the files in from > > > another source. > > > -- Charles > >