From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH 0/29] Page Table Interface Explanation From: Peter Zijlstra In-Reply-To: <20070113024540.29682.27024.sendpatchset@weill.orchestra.cse.unsw.EDU.AU> References: <20070113024540.29682.27024.sendpatchset@weill.orchestra.cse.unsw.EDU.AU> Content-Type: text/plain Date: Sat, 13 Jan 2007 20:29:01 +0100 Message-Id: <1168716541.5975.23.camel@lappy> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Paul Davies Cc: linux-mm@kvack.org List-ID: > PAGE TABLE INTERFACE > > int create_user_page_table(struct mm_struct *mm); > > void destroy_user_page_table(struct mm_struct *mm); > > pte_t *build_page_table(struct mm_struct *mm, unsigned long address, > pt_path_t *pt_path); > > pte_t *lookup_page_table(struct mm_struct *mm, unsigned long address, > pt_path_t *pt_path); > void free_pt_range(struct mmu_gather **tlb, unsigned long addr, > unsigned long end, unsigned long floor, unsigned long ceiling); > > int copy_dual_iterator(struct mm_struct *dst_mm, struct mm_struct *src_mm, > unsigned long addr, unsigned long end, struct vm_area_struct *vma); > > unsigned long unmap_page_range_iterator(struct mmu_gather *tlb, > struct vm_area_struct *vma, unsigned long addr, unsigned long end, > long *zap_work, struct zap_details *details); > > int zeromap_build_iterator(struct mm_struct *mm, > unsigned long addr, unsigned long end, pgprot_t prot); > > int remap_build_iterator(struct mm_struct *mm, > unsigned long addr, unsigned long end, unsigned long pfn, > pgprot_t prot); > > void change_protection_read_iterator(struct vm_area_struct *vma, > unsigned long addr, unsigned long end, pgprot_t newprot, > int dirty_accountable); > > void vunmap_read_iterator(unsigned long addr, unsigned long end); > > int vmap_build_iterator(unsigned long addr, > unsigned long end, pgprot_t prot, struct page ***pages); > > int unuse_vma_read_iterator(struct vm_area_struct *vma, > unsigned long addr, unsigned long end, swp_entry_t entry, struct page *page); > > void smaps_read_iterator(struct vm_area_struct *vma, > unsigned long addr, unsigned long end, struct mem_size_stats *mss); > > int check_policy_read_iterator(struct vm_area_struct *vma, > unsigned long addr, unsigned long end, const nodemask_t *nodes, > unsigned long flags, void *private); > > unsigned long move_page_tables(struct vm_area_struct *vma, > unsigned long old_addr, struct vm_area_struct *new_vma, > unsigned long new_addr, unsigned long len); > weird naming, functions are not iterators, if named after what they do it should be *_iteration. But still, I would have expected an iterator based interface; something along the lines of: typedef struct pti_struct { struct mm_struct *mm; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; spinlock_t *ptl; unsigned long address; } pti_t with accessors like: #define pti_address(pti) (pti).address #define pti_pte(pti) (pti).pte and methods like: bool pti_valid(pti_t *pti); pti_t pti_lookup(struct mm_struct *mm, unsigned long address); pti_t pti_acquire(struct mm_struct *mm, unsigned long address); void pti_release(pti_t *pti); bool pti_next(pti_t *pti); so that you could write the typical loops like: int ret = 0; pti_t *pri = pti_lookup(mm, start); do_for_each_pti_range(pti, end) { if (per_pte_op(pti_pte(pti))) { ret = -EFOO; break; } } while_for_each_pti_range(pti, end); pti_release(pti); return ret; where do_for_each_pti_range() and while_for_each_pti_range() look something like: #define do_for_each_pti_range(pti, end) \ if (pti_valid(pti) && pti_address(pti) < end) do #define while_for_each_pti_range(pti, end) \ while (pti_next(pti) && pti_valid(pti) && pti_address(pti) < end) -- 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