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allocate a large page in front of a FIXED mapping if start addr is not large page aligned so that the mapping remains physically contiguous

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Balazs Gerofi bgerofi@riken.jp
2012-11-03 16:58:52 +09:00
committed by Masamichi Takagi m-takagi@ab.jp.nec.com
parent a21fe11b00
commit 8979ccf5b8
1 changed files with 13 additions and 26 deletions
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39
kernel/syscall.c
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@@ -369,45 +369,32 @@ SYSCALL_DECLARE(mmap)
#ifdef USE_LARGE_PAGES
// use large pages if mapping is big enough
if (e - s >= LARGE_PAGE_SIZE) {
unsigned long old_s = s;
unsigned long p;
unsigned long p_aligned;
unsigned long s_orig = s;
unsigned long head_space = 0;
// fill in gap with regular pages until the first large
// page aligned address
// compute head space before the first large page aligned
// virtual address
if ((s & (LARGE_PAGE_SIZE - 1)) != 0) {
s = (s + (LARGE_PAGE_SIZE - 1)) & LARGE_PAGE_MASK;
// allocate physical address
pa = virt_to_phys(aal_mc_alloc_pages(
(s - old_s) >> PAGE_SHIFT, 0));
// add page_table, add memory-range
add_process_memory_range(cpu_local_var(current),
old_s, s, pa, 0);
dkprintf("filled in gap for LARGE_PAGE_SIZE aligned start: 0x%lX -> 0x%lX\n",
old_s, s);
head_space = (s - s_orig);
}
e = (e + (LARGE_PAGE_SIZE - 1)) & LARGE_PAGE_MASK;
p = (unsigned long)aal_mc_alloc_pages((e - s + LARGE_PAGE_SIZE)
>> PAGE_SHIFT, 0);
p_aligned = (p + (LARGE_PAGE_SIZE - 1)) & LARGE_PAGE_MASK;
p = (unsigned long)aal_mc_alloc_pages(
(e - s + 2 * LARGE_PAGE_SIZE) >> PAGE_SHIFT, 0);
// free unneeded
if (p_aligned > p) {
free_pages((void *)p, (p_aligned - (unsigned long)p)
>> PAGE_SHIFT);
}
p_aligned = (p + LARGE_PAGE_SIZE + (LARGE_PAGE_SIZE - 1))
& LARGE_PAGE_MASK;
// add range, mapping
add_process_memory_range(cpu_local_var(current), s, e,
virt_to_phys((void *)p_aligned), 0);
add_process_memory_range(cpu_local_var(current), s_orig, e,
virt_to_phys((void *)(p_aligned - head_space)), 0);
dkprintf("largePTE area: 0x%lX - 0x%lX (s: %lu) -> 0x%lX -\n",
s, e, (e - s), virt_to_phys((void *)p_aligned));
s_orig, e, (e - s_orig),
virt_to_phys((void *)(p_aligned - head_space)));
}
else {
#endif