Linux - SoftwareThis forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
We have an ARM based platform running kernel v2.6.18.For a particular driver, a physical space of around 2MB is required which would be shared by the device, driver and the application. The memory requirement
changes from application to application, so a memory manager manages the physical memory allocation on this shared area.
The device has MMU so, it doesn't require contiguous physical memory. The only condition is that the user space address must be contigous.
In the implementation we have used mmap to get a range of user virtual address, but have delayed the association of user virtual address with kernel virtual address till the our memory manager gives us the physical pages. Which means that remap_pfn_range is not called will memory is allocated by the manager.
We are able to associate a non-contiguous physical memory with contiguous user space address. The problem is that, we want to dissociate the user space address and the physical memory when the memory manager frees the space.
We tried using zap_page_range which doesn't work. Also unmap_range was used which gave kernel panic.
Could anybody let us know what is the way to unmap in such cases, or else an alternate way to achieve the same.