From mboxrd@z Thu Jan 1 00:00:00 1970 From: jeshkumar555@gmail.com (Jeshwanth Kumar N K) Date: Tue, 8 Jul 2014 01:26:26 +0530 Subject: USB file mmap In-Reply-To: <20140707163430.GA1137@kroah.com> References: <20140707163430.GA1137@kroah.com> Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Hi Greg, Thanks for the reply. I recently purchased an mbed board https://mbed.org/platforms/mbed-LPC1768/ (friend recommended) to learn USB Mass storage class. And used OpenLPC usb stack with fatfs example to check how it works (used protocol analyser and stuff, to know whats happening). In that they are reading each buffer, i mean copying buffer (8k) of data to RAM and process it. And other idea I found is using diskio function in openLPC stack to read the data in USB flash (but this is without file system). As a Linux user I knew in Linux we can do mmap easily for a file (with filesystem). So thought of asking from where to start understanding these concepts :). Greg is it OK to ask this question here? Thanks On 07-Jul-2014 10:00 pm, "Greg KH" wrote: > On Mon, Jul 07, 2014 at 07:30:07PM +0530, Jeshwanth Kumar N K wrote: > > Hello List, > > I am trying to understand mmap on files residing in USB flash, so can you > > please give a pointer from where I can start to understand this? I mean > how it > > works, and which part in kernel takes care of it. > > That's a _huge_ stack you are talking about here involving a vfs, the > memory management core, a filesystem, block layer, SCSI, and USB, at the > very least. > > What _exactly_ are you looking to understand here? And where in the > code have you looked and need help with? What documents have you read > that were unclear? And why do you need this information? > > greg k-h > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20140708/06775a0d/attachment.html