1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see
20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lustre/lustre/llite/rw26.c
38 * Lustre Lite I/O page cache routines for the 2.5/2.6 kernel version
41 #ifndef AUTOCONF_INCLUDED
42 #include <linux/config.h>
44 #include <linux/kernel.h>
46 #include <linux/string.h>
47 #include <linux/stat.h>
48 #include <linux/errno.h>
49 #include <linux/smp_lock.h>
50 #include <linux/unistd.h>
51 #include <linux/version.h>
52 #include <asm/system.h>
53 #include <asm/uaccess.h>
56 #include <linux/buffer_head.h>
57 #include <linux/writeback.h>
58 #include <linux/stat.h>
59 #include <asm/uaccess.h>
61 #include <linux/pagemap.h>
62 #include <linux/smp_lock.h>
64 #define DEBUG_SUBSYSTEM S_LLITE
66 //#include <lustre_mdc.h>
67 #include <lustre_lite.h>
68 #include "llite_internal.h"
69 #include <linux/lustre_compat25.h>
72 * Implements Linux VM address_space::invalidatepage() method. This method is
73 * called when the page is truncate from a file, either as a result of
74 * explicit truncate, or when inode is removed from memory (as a result of
75 * final iput(), umount, or memory pressure induced icache shrinking).
77 * [0, offset] bytes of the page remain valid (this is for a case of not-page
78 * aligned truncate). Lustre leaves partially truncated page in the cache,
79 * relying on struct inode::i_size to limit further accesses.
81 static int cl_invalidatepage(struct page *vmpage, unsigned long offset)
86 struct cl_object *obj;
91 LASSERT(PageLocked(vmpage));
92 LASSERT(!PageWriteback(vmpage));
95 * It is safe to not check anything in invalidatepage/releasepage
96 * below because they are run with page locked and all our io is
97 * happening with locked page too
101 env = cl_env_get(&refcheck);
103 inode = vmpage->mapping->host;
104 obj = ll_i2info(inode)->lli_clob;
106 page = cl_vmpage_page(vmpage, obj);
108 lu_ref_add(&page->cp_reference,
110 cl_page_delete(env, page);
112 lu_ref_del(&page->cp_reference,
114 cl_page_put(env, page);
117 LASSERT(vmpage->private == 0);
118 cl_env_put(env, &refcheck);
124 #ifdef HAVE_INVALIDATEPAGE_RETURN_INT
125 static int ll_invalidatepage(struct page *page, unsigned long offset)
127 return cl_invalidatepage(page, offset);
129 #else /* !HAVE_INVALIDATEPAGE_RETURN_INT */
130 static void ll_invalidatepage(struct page *page, unsigned long offset)
132 cl_invalidatepage(page, offset);
136 #ifdef HAVE_RELEASEPAGE_WITH_INT
137 #define RELEASEPAGE_ARG_TYPE int
139 #define RELEASEPAGE_ARG_TYPE gfp_t
141 static int ll_releasepage(struct page *page, RELEASEPAGE_ARG_TYPE gfp_mask)
145 cookie = cl_env_reenter();
146 ll_invalidatepage(page, 0);
147 cl_env_reexit(cookie);
151 static int ll_set_page_dirty(struct page *vmpage)
154 struct cl_page *page = vvp_vmpage_page_transient(vmpage);
155 struct vvp_object *obj = cl_inode2vvp(vmpage->mapping->host);
156 struct vvp_page *cpg;
159 * XXX should page method be called here?
161 LASSERT(&obj->co_cl == page->cp_obj);
162 cpg = cl2vvp_page(cl_page_at(page, &vvp_device_type));
164 * XXX cannot do much here, because page is possibly not locked:
166 * ->unmap_page_range()->zap_pte_range()->set_page_dirty().
168 vvp_write_pending(obj, cpg);
170 RETURN(__set_page_dirty_nobuffers(vmpage));
173 #define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL
175 static inline int ll_get_user_pages(int rw, unsigned long user_addr,
176 size_t size, struct page ***pages,
179 int result = -ENOMEM;
181 /* set an arbitrary limit to prevent arithmetic overflow */
182 if (size > MAX_DIRECTIO_SIZE) {
187 *max_pages = (user_addr + size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
188 *max_pages -= user_addr >> CFS_PAGE_SHIFT;
190 OBD_ALLOC_LARGE(*pages, *max_pages * sizeof(**pages));
192 down_read(¤t->mm->mmap_sem);
193 result = get_user_pages(current, current->mm, user_addr,
194 *max_pages, (rw == READ), 0, *pages,
196 up_read(¤t->mm->mmap_sem);
197 if (unlikely(result <= 0))
198 OBD_FREE_LARGE(*pages, *max_pages * sizeof(**pages));
204 /* ll_free_user_pages - tear down page struct array
205 * @pages: array of page struct pointers underlying target buffer */
206 static void ll_free_user_pages(struct page **pages, int npages, int do_dirty)
210 for (i = 0; i < npages; i++) {
211 if (pages[i] == NULL)
214 set_page_dirty_lock(pages[i]);
215 page_cache_release(pages[i]);
218 OBD_FREE_LARGE(pages, npages * sizeof(*pages));
221 ssize_t ll_direct_rw_pages(const struct lu_env *env, struct cl_io *io,
222 int rw, struct inode *inode,
223 struct ll_dio_pages *pv)
226 struct cl_2queue *queue;
227 struct cl_object *obj = io->ci_obj;
230 loff_t file_offset = pv->ldp_start_offset;
231 long size = pv->ldp_size;
232 int page_count = pv->ldp_nr;
233 struct page **pages = pv->ldp_pages;
234 long page_size = cl_page_size(obj);
239 queue = &io->ci_queue;
240 cl_2queue_init(queue);
241 for (i = 0; i < page_count; i++) {
243 file_offset = pv->ldp_offsets[i];
245 LASSERT(!(file_offset & (page_size - 1)));
246 clp = cl_page_find(env, obj, cl_index(obj, file_offset),
247 pv->ldp_pages[i], CPT_TRANSIENT);
253 rc = cl_page_own(env, io, clp);
255 LASSERT(clp->cp_state == CPS_FREEING);
256 cl_page_put(env, clp);
262 /* check the page type: if the page is a host page, then do
264 if (clp->cp_type == CPT_CACHEABLE) {
265 cfs_page_t *vmpage = cl_page_vmpage(env, clp);
266 cfs_page_t *src_page;
267 cfs_page_t *dst_page;
271 src_page = (rw == WRITE) ? pages[i] : vmpage;
272 dst_page = (rw == WRITE) ? vmpage : pages[i];
274 src = kmap_atomic(src_page, KM_USER0);
275 dst = kmap_atomic(dst_page, KM_USER1);
276 memcpy(dst, src, min(page_size, size));
277 kunmap_atomic(dst, KM_USER1);
278 kunmap_atomic(src, KM_USER0);
280 /* make sure page will be added to the transfer by
281 * cl_io_submit()->...->vvp_page_prep_write(). */
283 set_page_dirty(vmpage);
286 /* do not issue the page for read, since it
287 * may reread a ra page which has NOT uptodate
289 cl_page_disown(env, io, clp);
295 cl_2queue_add(queue, clp);
298 * Set page clip to tell transfer formation engine
299 * that page has to be sent even if it is beyond KMS.
301 cl_page_clip(env, clp, 0, min(size, page_size));
306 /* drop the reference count for cl_page_find */
307 cl_page_put(env, clp);
309 file_offset += page_size;
312 if (rc == 0 && io_pages) {
313 rc = cl_io_submit_sync(env, io,
314 rw == READ ? CRT_READ : CRT_WRITE,
315 queue, CRP_NORMAL, 0);
320 cl_2queue_discard(env, io, queue);
321 cl_2queue_disown(env, io, queue);
322 cl_2queue_fini(env, queue);
325 EXPORT_SYMBOL(ll_direct_rw_pages);
327 static ssize_t ll_direct_IO_26_seg(const struct lu_env *env, struct cl_io *io,
328 int rw, struct inode *inode,
329 struct address_space *mapping,
330 size_t size, loff_t file_offset,
331 struct page **pages, int page_count)
333 struct ll_dio_pages pvec = { .ldp_pages = pages,
334 .ldp_nr = page_count,
337 .ldp_start_offset = file_offset
340 return ll_direct_rw_pages(env, io, rw, inode, &pvec);
343 /* This is the maximum size of a single O_DIRECT request, based on a 128kB
344 * kmalloc limit. We need to fit all of the brw_page structs, each one
345 * representing PAGE_SIZE worth of user data, into a single buffer, and
346 * then truncate this to be a full-sized RPC. This is 22MB for 4kB pages. */
347 #define MAX_DIO_SIZE ((128 * 1024 / sizeof(struct brw_page) * CFS_PAGE_SIZE) & \
348 ~(PTLRPC_MAX_BRW_SIZE - 1))
349 static ssize_t ll_direct_IO_26(int rw, struct kiocb *iocb,
350 const struct iovec *iov, loff_t file_offset,
351 unsigned long nr_segs)
355 struct file *file = iocb->ki_filp;
356 struct inode *inode = file->f_mapping->host;
357 struct ccc_object *obj = cl_inode2ccc(inode);
358 long count = iov_length(iov, nr_segs);
359 long tot_bytes = 0, result = 0;
360 struct ll_inode_info *lli = ll_i2info(inode);
361 struct lov_stripe_md *lsm = lli->lli_smd;
362 unsigned long seg = 0;
363 long size = MAX_DIO_SIZE;
367 if (!lli->lli_smd || !lli->lli_smd->lsm_object_id)
370 /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
371 if ((file_offset & ~CFS_PAGE_MASK) || (count & ~CFS_PAGE_MASK))
374 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), size=%lu (max %lu), "
375 "offset=%lld=%llx, pages %lu (max %lu)\n",
376 inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE,
377 file_offset, file_offset, count >> CFS_PAGE_SHIFT,
378 MAX_DIO_SIZE >> CFS_PAGE_SHIFT);
380 /* Check that all user buffers are aligned as well */
381 for (seg = 0; seg < nr_segs; seg++) {
382 if (((unsigned long)iov[seg].iov_base & ~CFS_PAGE_MASK) ||
383 (iov[seg].iov_len & ~CFS_PAGE_MASK))
387 env = cl_env_get(&refcheck);
388 LASSERT(!IS_ERR(env));
389 io = ccc_env_io(env)->cui_cl.cis_io;
392 /* 0. Need locking between buffered and direct access. and race with
393 *size changing by concurrent truncates and writes.
394 * 1. Need inode sem to operate transient pages. */
396 LOCK_INODE_MUTEX(inode);
398 LASSERT(obj->cob_transient_pages == 0);
399 for (seg = 0; seg < nr_segs; seg++) {
400 long iov_left = iov[seg].iov_len;
401 unsigned long user_addr = (unsigned long)iov[seg].iov_base;
404 if (file_offset >= inode->i_size)
406 if (file_offset + iov_left > inode->i_size)
407 iov_left = inode->i_size - file_offset;
410 while (iov_left > 0) {
412 int page_count, max_pages = 0;
415 bytes = min(size,iov_left);
416 page_count = ll_get_user_pages(rw, user_addr, bytes,
418 if (likely(page_count > 0)) {
419 if (unlikely(page_count < max_pages))
420 bytes = page_count << CFS_PAGE_SHIFT;
421 result = ll_direct_IO_26_seg(env, io, rw, inode,
426 ll_free_user_pages(pages, max_pages, rw==READ);
427 } else if (page_count == 0) {
428 GOTO(out, result = -EFAULT);
432 if (unlikely(result <= 0)) {
433 /* If we can't allocate a large enough buffer
434 * for the request, shrink it to a smaller
435 * PAGE_SIZE multiple and try again.
436 * We should always be able to kmalloc for a
437 * page worth of page pointers = 4MB on i386. */
438 if (result == -ENOMEM &&
439 size > (CFS_PAGE_SIZE / sizeof(*pages)) *
441 size = ((((size / 2) - 1) |
442 ~CFS_PAGE_MASK) + 1) &
444 CDEBUG(D_VFSTRACE,"DIO size now %lu\n",
453 file_offset += result;
459 LASSERT(obj->cob_transient_pages == 0);
461 UNLOCK_INODE_MUTEX(inode);
465 lov_stripe_lock(lsm);
466 obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0);
467 lov_stripe_unlock(lsm);
471 cl_env_put(env, &refcheck);
472 RETURN(tot_bytes ? : result);
475 #ifdef HAVE_KERNEL_WRITE_BEGIN_END
476 static int ll_write_begin(struct file *file, struct address_space *mapping,
477 loff_t pos, unsigned len, unsigned flags,
478 struct page **pagep, void **fsdata)
480 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
483 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
486 page = grab_cache_page_write_begin(mapping, index, flags);
492 rc = ll_prepare_write(file, page, from, from + len);
495 page_cache_release(page);
500 static int ll_write_end(struct file *file, struct address_space *mapping,
501 loff_t pos, unsigned len, unsigned copied,
502 struct page *page, void *fsdata)
504 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
506 rc = ll_commit_write(file, page, from, from + copied);
509 page_cache_release(page);
514 #ifdef CONFIG_MIGRATION
515 int ll_migratepage(struct address_space *mapping,
516 struct page *newpage, struct page *page)
518 /* Always fail page migration until we have a proper implementation */
523 struct address_space_operations ll_aops = {
524 .readpage = ll_readpage,
525 // .readpages = ll_readpages,
526 .direct_IO = ll_direct_IO_26,
527 .writepage = ll_writepage,
528 .writepages = generic_writepages,
529 .set_page_dirty = ll_set_page_dirty,
531 #ifdef HAVE_KERNEL_WRITE_BEGIN_END
532 .write_begin = ll_write_begin,
533 .write_end = ll_write_end,
535 .prepare_write = ll_prepare_write,
536 .commit_write = ll_commit_write,
538 .invalidatepage = ll_invalidatepage,
539 .releasepage = (void *)ll_releasepage,
540 #ifdef CONFIG_MIGRATION
541 .migratepage = ll_migratepage,