xen_mm_pin_all()/unpin_all() are used to implement full guest instance suspend/restore. It's a stop-all method that needs to iterate through all allocated pgds in the system to fix them up for Xen's use.
This code uses pgd_list, probably because it was an easy interface. But we want to remove the pgd_list, so convert the code over to walk all tasks in the system. This is an equivalent method. (As I don't use Xen this is was only build tested.) Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Waiman Long <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/xen/mmu.c | 34 ++++++++++++++++++++++++++++------ 1 file changed, 28 insertions(+), 6 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index dd151b2045b0..87a8354435f8 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -853,18 +853,29 @@ static void xen_pgd_pin(struct mm_struct *mm) */ void xen_mm_pin_all(void) { - struct page *page; + struct task_struct *g, *p; + rcu_read_lock(); spin_lock(&pgd_lock); - list_for_each_entry(page, &pgd_list, lru) { + for_each_process_thread(g, p) { + struct page *page; + pgd_t *pgd; + + if (!p->mm) + continue; + + pgd = p->mm->pgd; + page = virt_to_page(pgd); + if (!PagePinned(page)) { - __xen_pgd_pin(&init_mm, (pgd_t *)page_address(page)); + __xen_pgd_pin(&init_mm, pgd); SetPageSavePinned(page); } } spin_unlock(&pgd_lock); + rcu_read_unlock(); } /* @@ -967,19 +978,30 @@ static void xen_pgd_unpin(struct mm_struct *mm) */ void xen_mm_unpin_all(void) { - struct page *page; + struct task_struct *g, *p; + rcu_read_lock(); spin_lock(&pgd_lock); - list_for_each_entry(page, &pgd_list, lru) { + for_each_process_thread(g, p) { + struct page *page; + pgd_t *pgd; + + if (!p->mm) + continue; + + pgd = p->mm->pgd; + page = virt_to_page(pgd); + if (PageSavePinned(page)) { BUG_ON(!PagePinned(page)); - __xen_pgd_unpin(&init_mm, (pgd_t *)page_address(page)); + __xen_pgd_unpin(&init_mm, pgd); ClearPageSavePinned(page); } } spin_unlock(&pgd_lock); + rcu_read_unlock(); } static void xen_activate_mm(struct mm_struct *prev, struct mm_struct *next) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
