From bae473a423f65e480db83c85b5e92254f6dfcb28 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 26 Jul 2016 15:25:20 -0700 Subject: mm: introduce fault_env The idea borrowed from Peter's patch from patchset on speculative page faults[1]: Instead of passing around the endless list of function arguments, replace the lot with a single structure so we can change context without endless function signature changes. The changes are mostly mechanical with exception of faultaround code: filemap_map_pages() got reworked a bit. This patch is preparation for the next one. [1] http://lkml.kernel.org/r/20141020222841.302891540@infradead.org Link: http://lkml.kernel.org/r/1466021202-61880-9-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Acked-by: Peter Zijlstra (Intel) Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/userfaultfd.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'fs/userfaultfd.c') diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 2d97952e341a..85959d8324df 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -257,10 +257,9 @@ out: * fatal_signal_pending()s, and the mmap_sem must be released before * returning it. */ -int handle_userfault(struct vm_area_struct *vma, unsigned long address, - unsigned int flags, unsigned long reason) +int handle_userfault(struct fault_env *fe, unsigned long reason) { - struct mm_struct *mm = vma->vm_mm; + struct mm_struct *mm = fe->vma->vm_mm; struct userfaultfd_ctx *ctx; struct userfaultfd_wait_queue uwq; int ret; @@ -269,7 +268,7 @@ int handle_userfault(struct vm_area_struct *vma, unsigned long address, BUG_ON(!rwsem_is_locked(&mm->mmap_sem)); ret = VM_FAULT_SIGBUS; - ctx = vma->vm_userfaultfd_ctx.ctx; + ctx = fe->vma->vm_userfaultfd_ctx.ctx; if (!ctx) goto out; @@ -302,17 +301,17 @@ int handle_userfault(struct vm_area_struct *vma, unsigned long address, * without first stopping userland access to the memory. For * VM_UFFD_MISSING userfaults this is enough for now. */ - if (unlikely(!(flags & FAULT_FLAG_ALLOW_RETRY))) { + if (unlikely(!(fe->flags & FAULT_FLAG_ALLOW_RETRY))) { /* * Validate the invariant that nowait must allow retry * to be sure not to return SIGBUS erroneously on * nowait invocations. */ - BUG_ON(flags & FAULT_FLAG_RETRY_NOWAIT); + BUG_ON(fe->flags & FAULT_FLAG_RETRY_NOWAIT); #ifdef CONFIG_DEBUG_VM if (printk_ratelimit()) { printk(KERN_WARNING - "FAULT_FLAG_ALLOW_RETRY missing %x\n", flags); + "FAULT_FLAG_ALLOW_RETRY missing %x\n", fe->flags); dump_stack(); } #endif @@ -324,7 +323,7 @@ int handle_userfault(struct vm_area_struct *vma, unsigned long address, * and wait. */ ret = VM_FAULT_RETRY; - if (flags & FAULT_FLAG_RETRY_NOWAIT) + if (fe->flags & FAULT_FLAG_RETRY_NOWAIT) goto out; /* take the reference before dropping the mmap_sem */ @@ -332,10 +331,11 @@ int handle_userfault(struct vm_area_struct *vma, unsigned long address, init_waitqueue_func_entry(&uwq.wq, userfaultfd_wake_function); uwq.wq.private = current; - uwq.msg = userfault_msg(address, flags, reason); + uwq.msg = userfault_msg(fe->address, fe->flags, reason); uwq.ctx = ctx; - return_to_userland = (flags & (FAULT_FLAG_USER|FAULT_FLAG_KILLABLE)) == + return_to_userland = + (fe->flags & (FAULT_FLAG_USER|FAULT_FLAG_KILLABLE)) == (FAULT_FLAG_USER|FAULT_FLAG_KILLABLE); spin_lock(&ctx->fault_pending_wqh.lock); @@ -353,7 +353,7 @@ int handle_userfault(struct vm_area_struct *vma, unsigned long address, TASK_KILLABLE); spin_unlock(&ctx->fault_pending_wqh.lock); - must_wait = userfaultfd_must_wait(ctx, address, flags, reason); + must_wait = userfaultfd_must_wait(ctx, fe->address, fe->flags, reason); up_read(&mm->mmap_sem); if (likely(must_wait && !ACCESS_ONCE(ctx->released) && -- cgit