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 2008 Sun Microsystems, Inc. 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/mpage.h>
58 #include <linux/writeback.h>
59 #include <linux/stat.h>
60 #include <asm/uaccess.h>
62 #include <linux/pagemap.h>
63 #include <linux/smp_lock.h>
65 #define DEBUG_SUBSYSTEM S_LLITE
67 //#include <lustre_mdc.h>
68 #include <lustre_lite.h>
69 #include "llite_internal.h"
70 #include <linux/lustre_compat25.h>
72 static int ll_writepage_26(struct page *page, struct writeback_control *wbc)
74 return ll_writepage(page);
77 /* It is safe to not check anything in invalidatepage/releasepage below
78 because they are run with page locked and all our io is happening with
80 #ifdef HAVE_INVALIDATEPAGE_RETURN_INT
81 static int ll_invalidatepage(struct page *page, unsigned long offset)
85 if (PagePrivate(page))
90 static void ll_invalidatepage(struct page *page, unsigned long offset)
92 if (offset == 0 && PagePrivate(page))
96 static int ll_releasepage(struct page *page, gfp_t gfp_mask)
98 if (PagePrivate(page))
103 static int ll_set_page_dirty(struct page *page)
105 struct ll_async_page *llap;
108 llap = llap_from_page(page, LLAP_ORIGIN_UNKNOWN);
110 RETURN(PTR_ERR(llap));
112 llap_write_pending(page->mapping->host, llap);
113 RETURN(__set_page_dirty_nobuffers(page));
116 #define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL
118 static inline int ll_get_user_pages(int rw, unsigned long user_addr,
119 size_t size, struct page ***pages)
121 int result = -ENOMEM;
124 /* set an arbitrary limit to prevent arithmetic overflow */
125 if (size > MAX_DIRECTIO_SIZE) {
130 page_count = (user_addr + size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
131 page_count -= user_addr >> CFS_PAGE_SHIFT;
133 OBD_ALLOC_WAIT(*pages, page_count * sizeof(**pages));
135 down_read(¤t->mm->mmap_sem);
136 result = get_user_pages(current, current->mm, user_addr,
137 page_count, (rw == READ), 0, *pages,
139 up_read(¤t->mm->mmap_sem);
141 OBD_FREE(*pages, page_count * sizeof(**pages));
147 /* ll_free_user_pages - tear down page struct array
148 * @pages: array of page struct pointers underlying target buffer */
149 static void ll_free_user_pages(struct page **pages, int npages, int do_dirty)
153 for (i = 0; i < npages; i++) {
155 set_page_dirty_lock(pages[i]);
156 page_cache_release(pages[i]);
159 OBD_FREE(pages, npages * sizeof(*pages));
162 static ssize_t ll_direct_IO_26_seg(int rw, struct inode *inode,
163 struct address_space *mapping,
164 struct obd_info *oinfo,
165 struct ptlrpc_request_set *set,
166 size_t size, loff_t file_offset,
167 struct page **pages, int page_count)
169 struct brw_page *pga;
174 OBD_ALLOC(pga, sizeof(*pga) * page_count);
176 CDEBUG(D_VFSTRACE, "sizeof(*pga) = %u page_count = %u\n",
177 (int)sizeof(*pga), page_count);
181 for (i = 0, length = size; length > 0;
182 length -=pga[i].count, file_offset +=pga[i].count,i++) {/*i last!*/
183 pga[i].pg = pages[i];
184 pga[i].off = file_offset;
185 /* To the end of the page, or the length, whatever is less */
186 pga[i].count = min_t(int, CFS_PAGE_SIZE -
187 (file_offset & ~CFS_PAGE_MASK),
191 POISON_PAGE(pages[i], 0x0d);
194 rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
195 ll_i2dtexp(inode), oinfo, page_count,
200 OBD_FREE(pga, sizeof(*pga) * page_count);
204 /* This is the maximum size of a single O_DIRECT request, based on a 128kB
205 * kmalloc limit. We need to fit all of the brw_page structs, each one
206 * representing PAGE_SIZE worth of user data, into a single buffer, and
207 * then truncate this to be a full-sized RPC. This is 22MB for 4kB pages. */
208 #define MAX_DIO_SIZE ((128 * 1024 / sizeof(struct brw_page) * CFS_PAGE_SIZE) & \
209 ~(PTLRPC_MAX_BRW_SIZE - 1))
210 static ssize_t ll_direct_IO_26(int rw, struct kiocb *iocb,
211 const struct iovec *iov, loff_t file_offset,
212 unsigned long nr_segs)
214 struct file *file = iocb->ki_filp;
215 struct inode *inode = file->f_mapping->host;
216 ssize_t count = iov_length(iov, nr_segs), tot_bytes = 0;
217 struct ll_inode_info *lli = ll_i2info(inode);
218 struct lov_stripe_md *lsm = lli->lli_smd;
219 struct ptlrpc_request_set *set;
220 struct obd_info oinfo;
222 unsigned long seg = 0;
223 size_t size = MAX_DIO_SIZE;
227 if (!lli->lli_smd || !lli->lli_smd->lsm_object_id)
230 /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
231 if ((file_offset & ~CFS_PAGE_MASK) || (count & ~CFS_PAGE_MASK))
234 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), size="LPSZ" (max %lu), "
235 "offset=%lld=%llx, pages "LPSZ" (max %lu)\n",
236 inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE,
237 file_offset, file_offset, count >> CFS_PAGE_SHIFT,
238 MAX_DIO_SIZE >> CFS_PAGE_SHIFT);
241 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_WRITE, count);
242 opc = CAPA_OPC_OSS_WRITE;
243 llap_write_pending(inode, NULL);
245 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_READ, count);
246 opc = CAPA_OPC_OSS_RW;
249 /* Check that all user buffers are aligned as well */
250 for (seg = 0; seg < nr_segs; seg++) {
251 if (((unsigned long)iov[seg].iov_base & ~CFS_PAGE_MASK) ||
252 (iov[seg].iov_len & ~CFS_PAGE_MASK))
256 set = ptlrpc_prep_set();
260 ll_inode_fill_obdo(inode, rw, &oa);
263 oinfo.oi_capa = ll_osscapa_get(inode, opc);
265 /* need locking between buffered and direct access. and race with
266 *size changing by concurrent truncates and writes. */
268 LOCK_INODE_MUTEX(inode);
270 for (seg = 0; seg < nr_segs; seg++) {
271 size_t iov_left = iov[seg].iov_len;
272 unsigned long user_addr = (unsigned long)iov[seg].iov_base;
275 if (file_offset >= inode->i_size)
277 if (file_offset + iov_left > inode->i_size)
278 iov_left = inode->i_size - file_offset;
281 while (iov_left > 0) {
286 page_count = ll_get_user_pages(rw, user_addr,
289 LASSERT(page_count != 0);
290 if (page_count > 0) {
291 result = ll_direct_IO_26_seg(rw, inode,
297 ll_free_user_pages(pages, page_count, rw==READ);
301 if (page_count < 0 || result <= 0) {
302 /* If we can't allocate a large enough buffer
303 * for the request, shrink it to a smaller
304 * PAGE_SIZE multiple and try again.
305 * We should always be able to kmalloc for a
306 * page worth of page pointers = 4MB on i386. */
307 if ((page_count == -ENOMEM||result == -ENOMEM)&&
308 size > (CFS_PAGE_SIZE / sizeof(*pages)) *
310 size = ((((size / 2) - 1) |
311 ~CFS_PAGE_MASK) + 1) &
313 CDEBUG(D_VFSTRACE, "DIO size now %u\n",
319 tot_bytes = page_count < 0 ? page_count : result;
320 GOTO(out, tot_bytes);
324 file_offset += result;
331 UNLOCK_INODE_MUTEX(inode);
336 rc = ptlrpc_set_wait(set);
339 } else if (rw == WRITE) {
340 lov_stripe_lock(lsm);
341 obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0);
342 lov_stripe_unlock(lsm);
346 capa_put(oinfo.oi_capa);
347 ptlrpc_set_destroy(set);
351 struct address_space_operations ll_aops = {
352 .readpage = ll_readpage,
353 // .readpages = ll_readpages,
354 .direct_IO = ll_direct_IO_26,
355 .writepage = ll_writepage_26,
356 .writepages = generic_writepages,
357 .set_page_dirty = ll_set_page_dirty,
359 .prepare_write = ll_prepare_write,
360 .commit_write = ll_commit_write,
361 .invalidatepage = ll_invalidatepage,
362 .releasepage = ll_releasepage,