Sorry for the confusion. I include how I wrote the page allocation and de-allocation code at the end of this email. And the full source code is attached as well.
Using vmalloc? So it's a large array. Thousands of entries, right?
Yes. The array is vmalloc-ed. So the array can have many entries.
> and each page is allocated by get_free_page(GFP_ATOMIC). And after
^
You are NOT using get_free_pages, right?
My design is: each element of the array can only hold one page of memory. So I just use get_free_page, not get_free_pages.
Not really. Memory allocation is a tricky area. You need to show the real
code. Not just explanation -- actual code that does not work for you.
Here is the code:
#This is the part of page allocation
// alloc page array
pg_array = (void *)vmalloc(nr_pages * sizeof(void *));
if (!pg_array) {
printk("<1>error vmalloc pg_array\n");
goto jump;
} else {
for (i = 0; i < nr_pages; i++) {
pg_array[i] = NULL;
}
for (i = 0; i < nr_pages; i++) {
pg_array[i] = (void *)get_free_page(GFP_ATOMIC);
if (!pg_array[i]) {
printk("<1>error get_free_page pg_array[%lu]\n", i);
}
}
}
#This is the part of page allocation
// alloc page array
pg_array = (void *)vmalloc(nr_pages * sizeof(void *));
if (!pg_array) {
printk("<1>error vmalloc pg_array\n");
goto jump;
} else {
for (i = 0; i < nr_pages; i++) {
pg_array[i] = NULL;
}
for (i = 0; i < nr_pages; i++) {
pg_array[i] = (void *)get_free_page(GFP_ATOMIC);
if (!pg_array[i]) {
printk("<1>error get_free_page pg_array[%lu]\n", i);
}
}
}
# This is the part of the page de-allocation
if (pg_array) {
for (i = 0; i < nr_pages; i++)
if (pg_array[i]) {
__free_page(pg_array[i]);
pg_array[i] = NULL;
}
vfree(pg_array);
pg_array = NULL;
}
Note: The full source code is included in the attachment. Thanks for your help.
Best Regards!
Fei
Attachment:
client-mem.c
Description: Binary data
