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, 2014, 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 "llite_internal.h"
55 #include <lustre_compat.h>
57 static const struct vm_operations_struct ll_file_vm_ops;
59 void policy_from_vma(ldlm_policy_data_t *policy,
60 struct vm_area_struct *vma, unsigned long addr,
63 policy->l_extent.start = ((addr - vma->vm_start) & PAGE_MASK) +
64 (vma->vm_pgoff << PAGE_CACHE_SHIFT);
65 policy->l_extent.end = (policy->l_extent.start + count - 1) |
69 struct vm_area_struct *our_vma(struct mm_struct *mm, unsigned long addr,
72 struct vm_area_struct *vma, *ret = NULL;
75 /* mmap_sem must have been held by caller. */
76 LASSERT(!down_write_trylock(&mm->mmap_sem));
78 for(vma = find_vma(mm, addr);
79 vma != NULL && vma->vm_start < (addr + count); vma = vma->vm_next) {
80 if (vma->vm_ops && vma->vm_ops == &ll_file_vm_ops &&
81 vma->vm_flags & VM_SHARED) {
90 * API independent part for page fault initialization.
91 * \param vma - virtual memory area addressed to page fault
92 * \param env - corespondent lu_env to processing
93 * \param nest - nested level
94 * \param index - page index corespondent to fault.
95 * \parm ra_flags - vma readahead flags.
97 * \return allocated and initialized env for fault operation.
98 * \retval EINVAL if env can't allocated
99 * \return other error codes from cl_io_init.
101 static struct cl_io *
102 ll_fault_io_init(struct vm_area_struct *vma, struct lu_env **env_ret,
103 struct cl_env_nest *nest, pgoff_t index,
104 unsigned long *ra_flags)
106 struct file *file = vma->vm_file;
107 struct inode *inode = file->f_dentry->d_inode;
109 struct cl_fault_io *fio;
115 if (ll_file_nolock(file))
116 RETURN(ERR_PTR(-EOPNOTSUPP));
119 * page fault can be called when lustre IO is
120 * already active for the current thread, e.g., when doing read/write
121 * against user level buffer mapped from Lustre buffer. To avoid
122 * stomping on existing context, optionally force an allocation of a new
125 env = cl_env_nested_get(nest);
127 RETURN(ERR_PTR(-EINVAL));
131 io = vvp_env_thread_io(env);
132 io->ci_obj = ll_i2info(inode)->lli_clob;
133 LASSERT(io->ci_obj != NULL);
135 fio = &io->u.ci_fault;
136 fio->ft_index = index;
137 fio->ft_executable = vma->vm_flags&VM_EXEC;
140 * disable VM_SEQ_READ and use VM_RAND_READ to make sure that
141 * the kernel will not read other pages not covered by ldlm in
142 * filemap_nopage. we do our readahead in ll_readpage.
144 if (ra_flags != NULL)
145 *ra_flags = vma->vm_flags & (VM_RAND_READ|VM_SEQ_READ);
146 vma->vm_flags &= ~VM_SEQ_READ;
147 vma->vm_flags |= VM_RAND_READ;
149 CDEBUG(D_MMAP, "vm_flags: %lx (%lu %d)\n", vma->vm_flags,
150 fio->ft_index, fio->ft_executable);
152 rc = cl_io_init(env, io, CIT_FAULT, io->ci_obj);
154 struct vvp_io *vio = vvp_env_io(env);
155 struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
157 LASSERT(vio->vui_cl.cis_io == io);
159 /* mmap lock must be MANDATORY it has to cache
161 io->ci_lockreq = CILR_MANDATORY;
166 cl_env_nested_put(nest, env);
173 /* Sharing code of page_mkwrite method for rhel5 and rhel6 */
174 static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage,
180 struct cl_env_nest nest;
184 struct ll_inode_info *lli;
187 LASSERT(vmpage != NULL);
189 io = ll_fault_io_init(vma, &env, &nest, vmpage->index, NULL);
191 GOTO(out, result = PTR_ERR(io));
193 result = io->ci_result;
195 GOTO(out_io, result);
197 io->u.ci_fault.ft_mkwrite = 1;
198 io->u.ci_fault.ft_writable = 1;
200 vio = vvp_env_io(env);
201 vio->u.fault.ft_vma = vma;
202 vio->u.fault.ft_vmpage = vmpage;
204 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
206 /* we grab lli_trunc_sem to exclude truncate case.
207 * Otherwise, we could add dirty pages into osc cache
208 * while truncate is on-going. */
209 inode = vvp_object_inode(io->ci_obj);
210 lli = ll_i2info(inode);
211 down_read(&lli->lli_trunc_sem);
213 result = cl_io_loop(env, io);
215 up_read(&lli->lli_trunc_sem);
217 cfs_restore_sigs(set);
220 struct inode *inode = vma->vm_file->f_dentry->d_inode;
221 struct ll_inode_info *lli = ll_i2info(inode);
224 if (vmpage->mapping == NULL) {
227 /* page was truncated and lock was cancelled, return
228 * ENODATA so that VM_FAULT_NOPAGE will be returned
229 * to handle_mm_fault(). */
232 } else if (!PageDirty(vmpage)) {
233 /* race, the page has been cleaned by ptlrpcd after
234 * it was unlocked, it has to be added into dirty
235 * cache again otherwise this soon-to-dirty page won't
236 * consume any grants, even worse if this page is being
237 * transferred because it will break RPC checksum.
241 CDEBUG(D_MMAP, "Race on page_mkwrite %p/%lu, page has "
242 "been written out, retry.\n",
243 vmpage, vmpage->index);
250 spin_lock(&lli->lli_lock);
251 lli->lli_flags |= LLIF_DATA_MODIFIED;
252 spin_unlock(&lli->lli_lock);
259 cl_env_nested_put(&nest, env);
261 CDEBUG(D_MMAP, "%s mkwrite with %d\n", current->comm, result);
262 LASSERT(ergo(result == 0, PageLocked(vmpage)));
267 static inline int to_fault_error(int result)
271 result = VM_FAULT_LOCKED;
274 result = VM_FAULT_NOPAGE;
277 result = VM_FAULT_OOM;
280 result = VM_FAULT_SIGBUS;
287 * Lustre implementation of a vm_operations_struct::fault() method, called by
288 * VM to server page fault (both in kernel and user space).
290 * \param vma - is virtiual area struct related to page fault
291 * \param vmf - structure which describe type and address where hit fault
293 * \return allocated and filled _locked_ page for address
294 * \retval VM_FAULT_ERROR on general error
295 * \retval NOPAGE_OOM not have memory for allocate new page
297 static int ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
301 struct vvp_io *vio = NULL;
303 unsigned long ra_flags;
304 struct cl_env_nest nest;
309 io = ll_fault_io_init(vma, &env, &nest, vmf->pgoff, &ra_flags);
311 RETURN(to_fault_error(PTR_ERR(io)));
313 result = io->ci_result;
315 vio = vvp_env_io(env);
316 vio->u.fault.ft_vma = vma;
317 vio->u.fault.ft_vmpage = NULL;
318 vio->u.fault.ft_vmf = vmf;
319 vio->u.fault.ft_flags = 0;
320 vio->u.fault.ft_flags_valid = 0;
322 /* May call ll_readpage() */
323 ll_cl_add(vma->vm_file, env, io);
325 result = cl_io_loop(env, io);
327 ll_cl_remove(vma->vm_file, env);
329 /* ft_flags are only valid if we reached
330 * the call to filemap_fault */
331 if (vio->u.fault.ft_flags_valid)
332 fault_ret = vio->u.fault.ft_flags;
334 vmpage = vio->u.fault.ft_vmpage;
335 if (result != 0 && vmpage != NULL) {
336 page_cache_release(vmpage);
341 cl_env_nested_put(&nest, env);
343 vma->vm_flags |= ra_flags;
344 if (result != 0 && !(fault_ret & VM_FAULT_RETRY))
345 fault_ret |= to_fault_error(result);
347 CDEBUG(D_MMAP, "%s fault %d/%d\n",
348 current->comm, fault_ret, result);
352 static int ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
355 bool printed = false;
359 /* Only SIGKILL and SIGTERM is allowed for fault/nopage/mkwrite
360 * so that it can be killed by admin but not cause segfault by
362 set = cfs_block_sigsinv(sigmask(SIGKILL) | sigmask(SIGTERM));
365 result = ll_fault0(vma, vmf);
366 LASSERT(!(result & VM_FAULT_LOCKED));
368 struct page *vmpage = vmf->page;
370 /* check if this page has been truncated */
372 if (unlikely(vmpage->mapping == NULL)) { /* unlucky */
374 page_cache_release(vmpage);
377 if (!printed && ++count > 16) {
378 CWARN("the page is under heavy contention,"
379 "maybe your app(%s) needs revising :-)\n",
387 result |= VM_FAULT_LOCKED;
389 cfs_restore_sigs(set);
393 static int ll_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
396 bool printed = false;
402 result = ll_page_mkwrite0(vma, vmf->page, &retry);
404 if (!printed && ++count > 16) {
405 CWARN("app(%s): the page %lu of file "DFID" is under"
406 " heavy contention\n",
407 current->comm, vmf->pgoff,
408 PFID(ll_inode2fid(vma->vm_file->f_dentry->d_inode)));
415 LASSERT(PageLocked(vmf->page));
416 result = VM_FAULT_LOCKED;
420 result = VM_FAULT_NOPAGE;
423 result = VM_FAULT_OOM;
426 result = VM_FAULT_RETRY;
429 result = VM_FAULT_SIGBUS;
437 * To avoid cancel the locks covering mmapped region for lock cache pressure,
438 * we track the mapped vma count in vvp_object::vob_mmap_cnt.
440 static void ll_vm_open(struct vm_area_struct * vma)
442 struct inode *inode = vma->vm_file->f_dentry->d_inode;
443 struct vvp_object *vob = cl_inode2vvp(inode);
446 LASSERT(vma->vm_file);
447 LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
448 atomic_inc(&vob->vob_mmap_cnt);
453 * Dual to ll_vm_open().
455 static void ll_vm_close(struct vm_area_struct *vma)
457 struct inode *inode = vma->vm_file->f_dentry->d_inode;
458 struct vvp_object *vob = cl_inode2vvp(inode);
461 LASSERT(vma->vm_file);
462 atomic_dec(&vob->vob_mmap_cnt);
463 LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
467 /* XXX put nice comment here. talk about __free_pte -> dirty pages and
468 * nopage's reference passing to the pte */
469 int ll_teardown_mmaps(struct address_space *mapping, __u64 first, __u64 last)
474 LASSERTF(last > first, "last "LPU64" first "LPU64"\n", last, first);
475 if (mapping_mapped(mapping)) {
477 unmap_mapping_range(mapping, first + PAGE_CACHE_SIZE - 1,
478 last - first + 1, 0);
484 static const struct vm_operations_struct ll_file_vm_ops = {
486 .page_mkwrite = ll_page_mkwrite,
488 .close = ll_vm_close,
491 int ll_file_mmap(struct file *file, struct vm_area_struct * vma)
493 struct inode *inode = file->f_dentry->d_inode;
497 if (ll_file_nolock(file))
500 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MAP, 1);
501 rc = generic_file_mmap(file, vma);
503 vma->vm_ops = &ll_file_vm_ops;
504 vma->vm_ops->open(vma);
505 /* update the inode's size and mtime */
506 rc = ll_glimpse_size(inode);