4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2011, 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
37 #include <linux/kernel.h>
39 #include <linux/string.h>
40 #include <linux/stat.h>
41 #include <linux/errno.h>
42 #include <linux/unistd.h>
43 #include <linux/version.h>
44 #include <asm/uaccess.h>
47 #include <linux/stat.h>
48 #include <asm/uaccess.h>
50 #include <linux/pagemap.h>
52 #define DEBUG_SUBSYSTEM S_LLITE
54 #include <lustre_lite.h>
55 #include "llite_internal.h"
56 #include <linux/lustre_compat25.h>
58 struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
61 static struct vm_operations_struct ll_file_vm_ops;
63 void policy_from_vma(ldlm_policy_data_t *policy,
64 struct vm_area_struct *vma, unsigned long addr,
67 policy->l_extent.start = ((addr - vma->vm_start) & CFS_PAGE_MASK) +
68 (vma->vm_pgoff << PAGE_CACHE_SHIFT);
69 policy->l_extent.end = (policy->l_extent.start + count - 1) |
73 struct vm_area_struct *our_vma(struct mm_struct *mm, unsigned long addr,
76 struct vm_area_struct *vma, *ret = NULL;
79 /* mmap_sem must have been held by caller. */
80 LASSERT(!down_write_trylock(&mm->mmap_sem));
82 for(vma = find_vma(mm, addr);
83 vma != NULL && vma->vm_start < (addr + count); vma = vma->vm_next) {
84 if (vma->vm_ops && vma->vm_ops == &ll_file_vm_ops &&
85 vma->vm_flags & VM_SHARED) {
94 * API independent part for page fault initialization.
95 * \param vma - virtual memory area addressed to page fault
96 * \param env - corespondent lu_env to processing
97 * \param nest - nested level
98 * \param index - page index corespondent to fault.
99 * \parm ra_flags - vma readahead flags.
101 * \return allocated and initialized env for fault operation.
102 * \retval EINVAL if env can't allocated
103 * \return other error codes from cl_io_init.
105 struct cl_io *ll_fault_io_init(struct vm_area_struct *vma,
106 struct lu_env **env_ret,
107 struct cl_env_nest *nest,
108 pgoff_t index, unsigned long *ra_flags)
110 struct file *file = vma->vm_file;
111 struct inode *inode = file->f_dentry->d_inode;
113 struct cl_fault_io *fio;
119 if (ll_file_nolock(file))
120 RETURN(ERR_PTR(-EOPNOTSUPP));
123 * page fault can be called when lustre IO is
124 * already active for the current thread, e.g., when doing read/write
125 * against user level buffer mapped from Lustre buffer. To avoid
126 * stomping on existing context, optionally force an allocation of a new
129 env = cl_env_nested_get(nest);
131 RETURN(ERR_PTR(-EINVAL));
135 io = ccc_env_thread_io(env);
136 io->ci_obj = ll_i2info(inode)->lli_clob;
137 LASSERT(io->ci_obj != NULL);
139 fio = &io->u.ci_fault;
140 fio->ft_index = index;
141 fio->ft_executable = vma->vm_flags&VM_EXEC;
144 * disable VM_SEQ_READ and use VM_RAND_READ to make sure that
145 * the kernel will not read other pages not covered by ldlm in
146 * filemap_nopage. we do our readahead in ll_readpage.
148 if (ra_flags != NULL)
149 *ra_flags = vma->vm_flags & (VM_RAND_READ|VM_SEQ_READ);
150 vma->vm_flags &= ~VM_SEQ_READ;
151 vma->vm_flags |= VM_RAND_READ;
153 CDEBUG(D_MMAP, "vm_flags: %lx (%lu %d)\n", vma->vm_flags,
154 fio->ft_index, fio->ft_executable);
156 rc = cl_io_init(env, io, CIT_FAULT, io->ci_obj);
158 struct ccc_io *cio = ccc_env_io(env);
159 struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
161 LASSERT(cio->cui_cl.cis_io == io);
163 /* mmap lock must be MANDATORY it has to cache
165 io->ci_lockreq = CILR_MANDATORY;
170 cl_env_nested_put(nest, env);
177 /* Sharing code of page_mkwrite method for rhel5 and rhel6 */
178 static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage,
184 struct cl_env_nest nest;
188 struct ll_inode_info *lli;
191 LASSERT(vmpage != NULL);
193 io = ll_fault_io_init(vma, &env, &nest, vmpage->index, NULL);
195 GOTO(out, result = PTR_ERR(io));
197 result = io->ci_result;
199 GOTO(out_io, result);
201 io->u.ci_fault.ft_mkwrite = 1;
202 io->u.ci_fault.ft_writable = 1;
204 vio = vvp_env_io(env);
205 vio->u.fault.ft_vma = vma;
206 vio->u.fault.ft_vmpage = vmpage;
208 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
210 /* we grab lli_trunc_sem to exclude truncate case.
211 * Otherwise, we could add dirty pages into osc cache
212 * while truncate is on-going. */
213 inode = ccc_object_inode(io->ci_obj);
214 lli = ll_i2info(inode);
215 down_read(&lli->lli_trunc_sem);
217 result = cl_io_loop(env, io);
219 up_read(&lli->lli_trunc_sem);
221 cfs_restore_sigs(set);
224 struct inode *inode = vma->vm_file->f_dentry->d_inode;
225 struct ll_inode_info *lli = ll_i2info(inode);
228 if (vmpage->mapping == NULL) {
231 /* page was truncated and lock was cancelled, return
232 * ENODATA so that VM_FAULT_NOPAGE will be returned
233 * to handle_mm_fault(). */
236 } else if (!PageDirty(vmpage)) {
237 /* race, the page has been cleaned by ptlrpcd after
238 * it was unlocked, it has to be added into dirty
239 * cache again otherwise this soon-to-dirty page won't
240 * consume any grants, even worse if this page is being
241 * transferred because it will break RPC checksum.
245 CDEBUG(D_MMAP, "Race on page_mkwrite %p/%lu, page has "
246 "been written out, retry.\n",
247 vmpage, vmpage->index);
254 spin_lock(&lli->lli_lock);
255 lli->lli_flags |= LLIF_DATA_MODIFIED;
256 spin_unlock(&lli->lli_lock);
263 cl_env_nested_put(&nest, env);
265 CDEBUG(D_MMAP, "%s mkwrite with %d\n", current->comm, result);
266 LASSERT(ergo(result == 0, PageLocked(vmpage)));
271 static inline int to_fault_error(int result)
275 result = VM_FAULT_LOCKED;
278 result = VM_FAULT_NOPAGE;
281 result = VM_FAULT_OOM;
284 result = VM_FAULT_SIGBUS;
291 * Lustre implementation of a vm_operations_struct::fault() method, called by
292 * VM to server page fault (both in kernel and user space).
294 * \param vma - is virtiual area struct related to page fault
295 * \param vmf - structure which describe type and address where hit fault
297 * \return allocated and filled _locked_ page for address
298 * \retval VM_FAULT_ERROR on general error
299 * \retval NOPAGE_OOM not have memory for allocate new page
301 static int ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
305 struct vvp_io *vio = NULL;
307 unsigned long ra_flags;
308 struct cl_env_nest nest;
313 io = ll_fault_io_init(vma, &env, &nest, vmf->pgoff, &ra_flags);
315 RETURN(to_fault_error(PTR_ERR(io)));
317 result = io->ci_result;
319 vio = vvp_env_io(env);
320 vio->u.fault.ft_vma = vma;
321 vio->u.fault.ft_vmpage = NULL;
322 vio->u.fault.fault.ft_vmf = vmf;
324 result = cl_io_loop(env, io);
326 fault_ret = vio->u.fault.fault.ft_flags;
327 vmpage = vio->u.fault.ft_vmpage;
328 if (result != 0 && vmpage != NULL) {
329 page_cache_release(vmpage);
334 cl_env_nested_put(&nest, env);
336 vma->vm_flags |= ra_flags;
337 if (result != 0 && !(fault_ret & VM_FAULT_RETRY))
338 fault_ret |= to_fault_error(result);
340 CDEBUG(D_MMAP, "%s fault %d/%d\n",
341 current->comm, fault_ret, result);
345 static int ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
348 bool printed = false;
352 /* Only SIGKILL and SIGTERM is allowed for fault/nopage/mkwrite
353 * so that it can be killed by admin but not cause segfault by
355 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
358 result = ll_fault0(vma, vmf);
359 LASSERT(!(result & VM_FAULT_LOCKED));
361 struct page *vmpage = vmf->page;
363 /* check if this page has been truncated */
365 if (unlikely(vmpage->mapping == NULL)) { /* unlucky */
367 page_cache_release(vmpage);
370 if (!printed && ++count > 16) {
371 CWARN("the page is under heavy contention,"
372 "maybe your app(%s) needs revising :-)\n",
380 result |= VM_FAULT_LOCKED;
382 cfs_restore_sigs(set);
386 static int ll_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
389 bool printed = false;
395 result = ll_page_mkwrite0(vma, vmf->page, &retry);
397 if (!printed && ++count > 16) {
398 CWARN("app(%s): the page %lu of file "DFID" is under"
399 " heavy contention\n",
400 current->comm, vmf->pgoff,
401 PFID(ll_inode2fid(vma->vm_file->f_dentry->d_inode)));
408 LASSERT(PageLocked(vmf->page));
409 result = VM_FAULT_LOCKED;
413 result = VM_FAULT_NOPAGE;
416 result = VM_FAULT_OOM;
419 result = VM_FAULT_RETRY;
422 result = VM_FAULT_SIGBUS;
430 * To avoid cancel the locks covering mmapped region for lock cache pressure,
431 * we track the mapped vma count in ccc_object::cob_mmap_cnt.
433 static void ll_vm_open(struct vm_area_struct * vma)
435 struct inode *inode = vma->vm_file->f_dentry->d_inode;
436 struct ccc_object *vob = cl_inode2ccc(inode);
439 LASSERT(vma->vm_file);
440 LASSERT(cfs_atomic_read(&vob->cob_mmap_cnt) >= 0);
441 cfs_atomic_inc(&vob->cob_mmap_cnt);
446 * Dual to ll_vm_open().
448 static void ll_vm_close(struct vm_area_struct *vma)
450 struct inode *inode = vma->vm_file->f_dentry->d_inode;
451 struct ccc_object *vob = cl_inode2ccc(inode);
454 LASSERT(vma->vm_file);
455 cfs_atomic_dec(&vob->cob_mmap_cnt);
456 LASSERT(cfs_atomic_read(&vob->cob_mmap_cnt) >= 0);
460 /* return the user space pointer that maps to a file offset via a vma */
461 static inline unsigned long file_to_user(struct vm_area_struct *vma, __u64 byte)
463 return vma->vm_start +
464 (byte - ((__u64)vma->vm_pgoff << PAGE_CACHE_SHIFT));
468 /* XXX put nice comment here. talk about __free_pte -> dirty pages and
469 * nopage's reference passing to the pte */
470 int ll_teardown_mmaps(struct address_space *mapping, __u64 first, __u64 last)
475 LASSERTF(last > first, "last "LPU64" first "LPU64"\n", last, first);
476 if (mapping_mapped(mapping)) {
478 unmap_mapping_range(mapping, first + PAGE_CACHE_SIZE - 1,
479 last - first + 1, 0);
485 static struct vm_operations_struct ll_file_vm_ops = {
487 .page_mkwrite = ll_page_mkwrite,
489 .close = ll_vm_close,
492 int ll_file_mmap(struct file *file, struct vm_area_struct * vma)
494 struct inode *inode = file->f_dentry->d_inode;
498 if (ll_file_nolock(file))
501 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MAP, 1);
502 rc = generic_file_mmap(file, vma);
504 vma->vm_ops = &ll_file_vm_ops;
505 vma->vm_ops->open(vma);
506 /* update the inode's size and mtime */
507 rc = ll_glimpse_size(inode);