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, Whamcloud, Inc.
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 << CFS_PAGE_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;
118 if (ll_file_nolock(file))
119 RETURN(ERR_PTR(-EOPNOTSUPP));
122 * page fault can be called when lustre IO is
123 * already active for the current thread, e.g., when doing read/write
124 * against user level buffer mapped from Lustre buffer. To avoid
125 * stomping on existing context, optionally force an allocation of a new
128 env = cl_env_nested_get(nest);
130 RETURN(ERR_PTR(-EINVAL));
134 io = ccc_env_thread_io(env);
135 io->ci_obj = ll_i2info(inode)->lli_clob;
136 LASSERT(io->ci_obj != NULL);
138 fio = &io->u.ci_fault;
139 fio->ft_index = index;
140 fio->ft_executable = vma->vm_flags&VM_EXEC;
143 * disable VM_SEQ_READ and use VM_RAND_READ to make sure that
144 * the kernel will not read other pages not covered by ldlm in
145 * filemap_nopage. we do our readahead in ll_readpage.
147 if (ra_flags != NULL)
148 *ra_flags = vma->vm_flags & (VM_RAND_READ|VM_SEQ_READ);
149 vma->vm_flags &= ~VM_SEQ_READ;
150 vma->vm_flags |= VM_RAND_READ;
152 CDEBUG(D_MMAP, "vm_flags: %lx (%lu %d)\n", vma->vm_flags,
153 fio->ft_index, fio->ft_executable);
155 if (cl_io_init(env, io, CIT_FAULT, io->ci_obj) == 0) {
156 struct ccc_io *cio = ccc_env_io(env);
157 struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
159 LASSERT(cio->cui_cl.cis_io == io);
161 /* mmap lock must be MANDATORY
162 * it has to cache pages. */
163 io->ci_lockreq = CILR_MANDATORY;
171 /* Sharing code of page_mkwrite method for rhel5 and rhel6 */
172 static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage,
178 struct cl_env_nest nest;
183 LASSERT(vmpage != NULL);
185 io = ll_fault_io_init(vma, &env, &nest, vmpage->index, NULL);
187 GOTO(out, result = PTR_ERR(io));
189 result = io->ci_result;
193 /* Don't enqueue new locks for page_mkwrite().
194 * If the lock has been cancelled then page must have been
195 * truncated, in that case, kernel will handle it.
197 io->ci_lockreq = CILR_PEEK;
198 io->u.ci_fault.ft_mkwrite = 1;
199 io->u.ci_fault.ft_writable = 1;
201 vio = vvp_env_io(env);
202 vio->u.fault.ft_vma = vma;
203 vio->u.fault.ft_vmpage = vmpage;
205 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
206 result = cl_io_loop(env, io);
207 cfs_restore_sigs(set);
209 if (result == -ENODATA) /* peek failed, no lock caching. */
210 CDEBUG(D_MMAP, "race on page_mkwrite: %lx (%lu %p)\n",
211 vma->vm_flags, io->u.ci_fault.ft_index, vmpage);
213 if (result == 0 || result == -ENODATA) {
215 if (vmpage->mapping == NULL) {
218 /* page was truncated and lock was cancelled, return
219 * ENODATA so that VM_FAULT_NOPAGE will be returned
220 * to handle_mm_fault(). */
223 } else if (result == -ENODATA) {
224 /* Invalidate it if the cl_lock is being revoked.
225 * This piece of code is definitely needed for RHEL5,
226 * otherwise, SIGBUS will be wrongly returned to
228 write_one_page(vmpage, 1);
230 if (vmpage->mapping != NULL) {
231 ll_invalidate_page(vmpage);
232 LASSERT(vmpage->mapping == NULL);
235 } else if (!PageDirty(vmpage)) {
236 /* race, the page has been cleaned by ptlrpcd after
237 * it was unlocked, it has to be added into dirty
238 * cache again otherwise this soon-to-dirty page won't
239 * consume any grants, even worse if this page is being
240 * transferred because it will break RPC checksum.
244 CDEBUG(D_MMAP, "Race on page_mkwrite %p/%lu, page has "
245 "been written out, retry.\n",
246 vmpage, vmpage->index);
256 cl_env_nested_put(&nest, env);
258 CDEBUG(D_MMAP, "%s mkwrite with %d\n", cfs_current()->comm, result);
260 LASSERT(ergo(result == 0, PageLocked(vmpage)));
265 #ifndef HAVE_VM_OP_FAULT
267 * Lustre implementation of a vm_operations_struct::nopage() method, called by
268 * VM to server page fault (both in kernel and user space).
270 * This function sets up CIT_FAULT cl_io that does the job.
272 * \param vma - is virtiual area struct related to page fault
273 * \param address - address when hit fault
274 * \param type - of fault
276 * \return allocated and filled _unlocked_ page for address
277 * \retval NOPAGE_SIGBUS if page not exist on this address
278 * \retval NOPAGE_OOM not have memory for allocate new page
280 struct page *ll_nopage(struct vm_area_struct *vma, unsigned long address,
284 struct cl_env_nest nest;
286 struct page *page = NOPAGE_SIGBUS;
287 struct vvp_io *vio = NULL;
288 unsigned long ra_flags;
291 const unsigned long writable = VM_SHARED|VM_WRITE;
295 pg_offset = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
296 io = ll_fault_io_init(vma, &env, &nest, pg_offset, &ra_flags);
298 return NOPAGE_SIGBUS;
300 result = io->ci_result;
304 io->u.ci_fault.ft_writable = (vma->vm_flags&writable) == writable;
306 vio = vvp_env_io(env);
307 vio->u.fault.ft_vma = vma;
308 vio->u.fault.nopage.ft_address = address;
309 vio->u.fault.nopage.ft_type = type;
310 vio->u.fault.ft_vmpage = NULL;
312 set = cfs_block_sigsinv(sigmask(SIGKILL)|sigmask(SIGTERM));
313 result = cl_io_loop(env, io);
314 cfs_restore_sigs(set);
316 page = vio->u.fault.ft_vmpage;
317 if (result != 0 && page != NULL) {
318 page_cache_release(page);
319 page = NOPAGE_SIGBUS;
323 if (result == -ENOMEM)
326 vma->vm_flags &= ~VM_RAND_READ;
327 vma->vm_flags |= ra_flags;
330 cl_env_nested_put(&nest, env);
337 static inline int to_fault_error(int result)
341 result = VM_FAULT_LOCKED;
344 result = VM_FAULT_NOPAGE;
347 result = VM_FAULT_OOM;
350 result = VM_FAULT_SIGBUS;
357 * Lustre implementation of a vm_operations_struct::fault() method, called by
358 * VM to server page fault (both in kernel and user space).
360 * \param vma - is virtiual area struct related to page fault
361 * \param vmf - structure which describe type and address where hit fault
363 * \return allocated and filled _locked_ page for address
364 * \retval VM_FAULT_ERROR on general error
365 * \retval NOPAGE_OOM not have memory for allocate new page
367 static int ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
371 struct vvp_io *vio = NULL;
373 unsigned long ra_flags;
374 struct cl_env_nest nest;
379 io = ll_fault_io_init(vma, &env, &nest, vmf->pgoff, &ra_flags);
381 RETURN(to_fault_error(PTR_ERR(io)));
383 result = io->ci_result;
385 vio = vvp_env_io(env);
386 vio->u.fault.ft_vma = vma;
387 vio->u.fault.ft_vmpage = NULL;
388 vio->u.fault.fault.ft_vmf = vmf;
390 result = cl_io_loop(env, io);
392 fault_ret = vio->u.fault.fault.ft_flags;
393 vmpage = vio->u.fault.ft_vmpage;
394 if (result != 0 && vmpage != NULL) {
395 page_cache_release(vmpage);
400 cl_env_nested_put(&nest, env);
402 vma->vm_flags |= ra_flags;
403 if (result != 0 && !(fault_ret & VM_FAULT_RETRY))
404 fault_ret |= to_fault_error(result);
406 CDEBUG(D_MMAP, "%s fault %d/%d\n",
407 cfs_current()->comm, fault_ret, result);
411 static int ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
414 bool printed = false;
418 /* Only SIGKILL and SIGTERM is allowed for fault/nopage/mkwrite
419 * so that it can be killed by admin but not cause segfault by
421 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
424 result = ll_fault0(vma, vmf);
425 LASSERT(!(result & VM_FAULT_LOCKED));
427 struct page *vmpage = vmf->page;
429 /* check if this page has been truncated */
431 if (unlikely(vmpage->mapping == NULL)) { /* unlucky */
433 page_cache_release(vmpage);
436 if (!printed && ++count > 16) {
437 CWARN("the page is under heavy contention,"
438 "maybe your app(%s) needs revising :-)\n",
446 result |= VM_FAULT_LOCKED;
448 cfs_restore_sigs(set);
453 #ifndef HAVE_PGMKWRITE_USE_VMFAULT
454 static int ll_page_mkwrite(struct vm_area_struct *vma, struct page *vmpage)
457 bool printed = false;
463 result = ll_page_mkwrite0(vma, vmpage, &retry);
465 if (!printed && ++count > 16) {
466 CWARN("app(%s): the page %lu of file %lu is under heavy"
468 current->comm, page_index(vmpage),
469 vma->vm_file->f_dentry->d_inode->i_ino);
476 else if (result == -ENODATA)
477 result = 0; /* kernel will know truncate has happened and
483 static int ll_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
486 bool printed = false;
492 result = ll_page_mkwrite0(vma, vmf->page, &retry);
494 if (!printed && ++count > 16) {
495 CWARN("app(%s): the page %lu of file %lu is under heavy"
497 current->comm, vmf->pgoff,
498 vma->vm_file->f_dentry->d_inode->i_ino);
505 LASSERT(PageLocked(vmf->page));
506 result = VM_FAULT_LOCKED;
510 result = VM_FAULT_NOPAGE;
513 result = VM_FAULT_OOM;
516 result = VM_FAULT_RETRY;
519 result = VM_FAULT_SIGBUS;
528 * To avoid cancel the locks covering mmapped region for lock cache pressure,
529 * we track the mapped vma count in ccc_object::cob_mmap_cnt.
531 static void ll_vm_open(struct vm_area_struct * vma)
533 struct inode *inode = vma->vm_file->f_dentry->d_inode;
534 struct ccc_object *vob = cl_inode2ccc(inode);
537 LASSERT(vma->vm_file);
538 LASSERT(cfs_atomic_read(&vob->cob_mmap_cnt) >= 0);
539 cfs_atomic_inc(&vob->cob_mmap_cnt);
544 * Dual to ll_vm_open().
546 static void ll_vm_close(struct vm_area_struct *vma)
548 struct inode *inode = vma->vm_file->f_dentry->d_inode;
549 struct ccc_object *vob = cl_inode2ccc(inode);
552 LASSERT(vma->vm_file);
553 cfs_atomic_dec(&vob->cob_mmap_cnt);
554 LASSERT(cfs_atomic_read(&vob->cob_mmap_cnt) >= 0);
558 #ifndef HAVE_VM_OP_FAULT
559 #ifndef HAVE_FILEMAP_POPULATE
560 static int (*filemap_populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock);
562 static int ll_populate(struct vm_area_struct *area, unsigned long address,
563 unsigned long len, pgprot_t prot, unsigned long pgoff,
569 /* always set nonblock as true to avoid page read ahead */
570 rc = filemap_populate(area, address, len, prot, pgoff, 1);
575 /* return the user space pointer that maps to a file offset via a vma */
576 static inline unsigned long file_to_user(struct vm_area_struct *vma, __u64 byte)
578 return vma->vm_start + (byte - ((__u64)vma->vm_pgoff << CFS_PAGE_SHIFT));
582 /* XXX put nice comment here. talk about __free_pte -> dirty pages and
583 * nopage's reference passing to the pte */
584 int ll_teardown_mmaps(struct address_space *mapping, __u64 first, __u64 last)
589 LASSERTF(last > first, "last "LPU64" first "LPU64"\n", last, first);
590 if (mapping_mapped(mapping)) {
592 unmap_mapping_range(mapping, first + CFS_PAGE_SIZE - 1,
593 last - first + 1, 0);
599 static struct vm_operations_struct ll_file_vm_ops = {
600 #ifndef HAVE_VM_OP_FAULT
602 .populate = ll_populate,
606 #ifndef HAVE_PGMKWRITE_COMPACT
607 .page_mkwrite = ll_page_mkwrite,
609 ._pmkw.page_mkwrite = ll_page_mkwrite,
612 .close = ll_vm_close,
615 int ll_file_mmap(struct file *file, struct vm_area_struct * vma)
617 struct inode *inode = file->f_dentry->d_inode;
621 if (ll_file_nolock(file))
624 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MAP, 1);
625 rc = generic_file_mmap(file, vma);
627 #if !defined(HAVE_FILEMAP_POPULATE) && !defined(HAVE_VM_OP_FAULT)
628 if (!filemap_populate)
629 filemap_populate = vma->vm_ops->populate;
631 vma->vm_ops = &ll_file_vm_ops;
632 vma->vm_ops->open(vma);
633 /* update the inode's size and mtime */
634 rc = ll_glimpse_size(inode);