From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <441FEFB4.6050700@yahoo.com.au> Date: Tue, 21 Mar 2006 23:21:08 +1100 From: Nick Piggin MIME-Version: 1.0 Subject: Re: PATCH][1/8] 2.6.15 mlock: make_pages_wired/unwired References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Stone Wang Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Stone Wang wrote: > 1. Add make_pages_unwired routine. Unfortunately you forgot wire_page and unwire_page, so this patch will not even compile. > 2. Replace make_pages_present with make_pages_wired, support rollback. What does support rollback mean? > 3. Pass 1 more param ("wire") to get_user_pages. > As others have pointed out, wire may be a BSD / other unix thing, but it does not feature in Linux memory management terminology. If you want to introduce it, you need to do a better job of specifying it. > Signed-off-by: Shaoping Wang > > +void make_pages_unwired(struct mm_struct *mm, > + unsigned long start,unsigned long end) > +{ > + struct vm_area_struct *vma; > + struct page *page; > + unsigned int foll_flags; > + > + foll_flags =0; > + > + vma=find_vma(mm,start); > + if(!vma) > + BUG(); > + if(is_vm_hugetlb_page(vma)) > + return; > + > + for(; start + page=follow_page(vma,start,foll_flags); > + if(page) > + unwire_page(page); > + } > +} > + What happens when start goes past vma->vm_end? > int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, > - unsigned long start, int len, int write, int force, > + unsigned long start, int len, int write,int force, int wire, > struct page **pages, struct vm_area_struct **vmas) > { > int i; > @@ -973,6 +995,7 @@ > if (!vma && in_gate_area(tsk, start)) { > unsigned long pg = start & PAGE_MASK; > struct vm_area_struct *gate_vma = get_gate_vma(tsk); > + struct page *page; > pgd_t *pgd; > pud_t *pud; > pmd_t *pmd; > @@ -994,6 +1017,7 @@ > pte_unmap(pte); > return i ? : -EFAULT; > } > + page = vm_normal_page(gate_vma, start, *pte); You wire gate_vma pages? But it doesn't look like you can unwire them with make_pages_unwired. > if (pages) { > struct page *page = vm_normal_page(gate_vma, start, *pte); This can go now? > pages[i] = page; > @@ -1003,9 +1027,12 @@ > pte_unmap(pte); > if (vmas) > vmas[i] = gate_vma; > + if(wire) > + wire_page(page); > i++; > start += PAGE_SIZE; > len--; > + > continue; > } > > @@ -1013,6 +1040,7 @@ > || !(vm_flags & vma->vm_flags)) > return i ? : -EFAULT; > > + /* We dont account wired HugeTLB pages */ You don't account wired HugeTLB pages? If you can wire them you should be able to unwire them as well shouldn't you? -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org