Hello:
I looked at the implementation of kiovec (map_user_kiobuf() routine).
I understood how to get the 'struct page *' for the user buffer.
What I want to know is,
If I want to print the contents of the user buffer (in the kernel)
using this 'struct page *' how do I do it ('struct page *' points
to the physical page right)?
I want to use kiovec for my driver, but I do not want to use the same
interface, but something similar to it.
Thanks,
Pramodh
I have the relevant code here. Please comment on this.
This is what I have done in the code similar to map_user_kiobuf(). I have
cut n pasted the relevant code only.
my_user_buf_map_routine(unsigned long addr) /* user addr */
{
int offset;
unsigned long ptr;
struct vm_area_struct *vma;
struct page *map;
unsigned long buf;
char *page_buffer;
offset = addr & PAGE_MASK;
ptr = addr & PAGE_MASK;
vma = find_vma(current->mm, ptr);
handle_mm_fault(current, vma, ptr, (rw==READ));
map = follow_page(ptr);
buf = page_address(map);
page_buffer = (char *) (buf + offset);
/* If i try to print the page_buffer it seg_faults
but I get a valid pointer to the map (struct page *)
*/
}
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