1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Lustre Lite I/O page cache routines for the 2.5/2.6 kernel version
6 * Copyright (c) 2001-2003 Cluster File Systems, Inc.
8 * This file is part of Lustre, http://www.lustre.org.
10 * Lustre is free software; you can redistribute it and/or
11 * modify it under the terms of version 2 of the GNU General Public
12 * License as published by the Free Software Foundation.
14 * Lustre is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with Lustre; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #ifndef AUTOCONF_INCLUDED
25 #include <linux/config.h>
27 #include <linux/kernel.h>
29 #include <linux/string.h>
30 #include <linux/stat.h>
31 #include <linux/errno.h>
32 #include <linux/smp_lock.h>
33 #include <linux/unistd.h>
34 #include <linux/version.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
39 #include <linux/buffer_head.h>
40 #include <linux/mpage.h>
41 #include <linux/writeback.h>
42 #include <linux/stat.h>
43 #include <asm/uaccess.h>
45 #include <linux/pagemap.h>
46 #include <linux/smp_lock.h>
48 #define DEBUG_SUBSYSTEM S_LLITE
50 //#include <lustre_mdc.h>
51 #include <lustre_lite.h>
52 #include "llite_internal.h"
53 #include <linux/lustre_compat25.h>
55 static int ll_writepage_26(struct page *page, struct writeback_control *wbc)
57 return ll_writepage(page);
60 /* It is safe to not check anything in invalidatepage/releasepage below
61 because they are run with page locked and all our io is happening with
63 #ifdef HAVE_INVALIDATEPAGE_RETURN_INT
64 static int ll_invalidatepage(struct page *page, unsigned long offset)
68 if (PagePrivate(page))
73 static void ll_invalidatepage(struct page *page, unsigned long offset)
75 if (offset == 0 && PagePrivate(page))
79 static int ll_releasepage(struct page *page, gfp_t gfp_mask)
81 if (PagePrivate(page))
86 static int ll_set_page_dirty(struct page *page)
88 struct ll_async_page *llap;
91 llap = llap_from_page(page, LLAP_ORIGIN_UNKNOWN);
93 RETURN(PTR_ERR(llap));
95 llap_write_pending(page->mapping->host, llap);
96 RETURN(__set_page_dirty_nobuffers(page));
99 #define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL
101 static inline int ll_get_user_pages(int rw, unsigned long user_addr,
102 size_t size, struct page ***pages)
104 int result = -ENOMEM;
107 /* set an arbitrary limit to prevent arithmetic overflow */
108 if (size > MAX_DIRECTIO_SIZE) {
113 page_count = (user_addr + size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
114 page_count -= user_addr >> CFS_PAGE_SHIFT;
116 OBD_ALLOC_WAIT(*pages, page_count * sizeof(**pages));
118 down_read(¤t->mm->mmap_sem);
119 result = get_user_pages(current, current->mm, user_addr,
120 page_count, (rw == READ), 0, *pages,
122 up_read(¤t->mm->mmap_sem);
124 OBD_FREE(*pages, page_count * sizeof(**pages));
130 /* ll_free_user_pages - tear down page struct array
131 * @pages: array of page struct pointers underlying target buffer */
132 static void ll_free_user_pages(struct page **pages, int npages, int do_dirty)
136 for (i = 0; i < npages; i++) {
138 set_page_dirty_lock(pages[i]);
139 page_cache_release(pages[i]);
142 OBD_FREE(pages, npages * sizeof(*pages));
145 static ssize_t ll_direct_IO_26_seg(int rw, struct inode *inode,
146 struct address_space *mapping,
147 struct obd_info *oinfo,
148 struct ptlrpc_request_set *set,
149 size_t size, loff_t file_offset,
150 struct page **pages, int page_count)
152 struct brw_page *pga;
157 OBD_ALLOC(pga, sizeof(*pga) * page_count);
159 CDEBUG(D_VFSTRACE, "sizeof(*pga) = %u page_count = %u\n",
160 (int)sizeof(*pga), page_count);
164 for (i = 0, length = size; length > 0;
165 length -=pga[i].count, file_offset +=pga[i].count,i++) {/*i last!*/
166 pga[i].pg = pages[i];
167 pga[i].off = file_offset;
168 /* To the end of the page, or the length, whatever is less */
169 pga[i].count = min_t(int, CFS_PAGE_SIZE -
170 (file_offset & ~CFS_PAGE_MASK),
174 POISON_PAGE(pages[i], 0x0d);
177 rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
178 ll_i2dtexp(inode), oinfo, page_count,
183 OBD_FREE(pga, sizeof(*pga) * page_count);
187 /* This is the maximum size of a single O_DIRECT request, based on a 128kB
188 * kmalloc limit. We need to fit all of the brw_page structs, each one
189 * representing PAGE_SIZE worth of user data, into a single buffer, and
190 * then truncate this to be a full-sized RPC. This is 22MB for 4kB pages. */
191 #define MAX_DIO_SIZE ((128 * 1024 / sizeof(struct brw_page) * CFS_PAGE_SIZE) & \
192 ~(PTLRPC_MAX_BRW_SIZE - 1))
193 static ssize_t ll_direct_IO_26(int rw, struct kiocb *iocb,
194 const struct iovec *iov, loff_t file_offset,
195 unsigned long nr_segs)
197 struct file *file = iocb->ki_filp;
198 struct inode *inode = file->f_mapping->host;
199 ssize_t count = iov_length(iov, nr_segs), tot_bytes = 0;
200 struct ll_inode_info *lli = ll_i2info(inode);
201 struct lov_stripe_md *lsm = lli->lli_smd;
202 struct ptlrpc_request_set *set;
203 struct obd_info oinfo;
205 unsigned long seg = 0;
206 size_t size = MAX_DIO_SIZE;
210 if (!lli->lli_smd || !lli->lli_smd->lsm_object_id)
213 /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
214 if ((file_offset & ~CFS_PAGE_MASK) || (count & ~CFS_PAGE_MASK))
217 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), size="LPSZ" (max %lu), "
218 "offset=%lld=%llx, pages "LPSZ" (max %lu)\n",
219 inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE,
220 file_offset, file_offset, count >> CFS_PAGE_SHIFT,
221 MAX_DIO_SIZE >> CFS_PAGE_SHIFT);
224 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_WRITE, count);
225 opc = CAPA_OPC_OSS_WRITE;
226 llap_write_pending(inode, NULL);
228 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_READ, count);
229 opc = CAPA_OPC_OSS_RW;
232 /* Check that all user buffers are aligned as well */
233 for (seg = 0; seg < nr_segs; seg++) {
234 if (((unsigned long)iov[seg].iov_base & ~CFS_PAGE_MASK) ||
235 (iov[seg].iov_len & ~CFS_PAGE_MASK))
239 set = ptlrpc_prep_set();
243 ll_inode_fill_obdo(inode, rw, &oa);
246 oinfo.oi_capa = ll_osscapa_get(inode, opc);
248 /* need locking between buffered and direct access. and race with
249 *size changing by concurrent truncates and writes. */
251 LOCK_INODE_MUTEX(inode);
253 for (seg = 0; seg < nr_segs; seg++) {
254 size_t iov_left = iov[seg].iov_len;
255 unsigned long user_addr = (unsigned long)iov[seg].iov_base;
258 if (file_offset >= inode->i_size)
260 if (file_offset + iov_left > inode->i_size)
261 iov_left = inode->i_size - file_offset;
264 while (iov_left > 0) {
269 page_count = ll_get_user_pages(rw, user_addr,
272 LASSERT(page_count != 0);
273 if (page_count > 0) {
274 result = ll_direct_IO_26_seg(rw, inode,
280 ll_free_user_pages(pages, page_count, rw==READ);
284 if (page_count < 0 || result <= 0) {
285 /* If we can't allocate a large enough buffer
286 * for the request, shrink it to a smaller
287 * PAGE_SIZE multiple and try again.
288 * We should always be able to kmalloc for a
289 * page worth of page pointers = 4MB on i386. */
290 if ((page_count == -ENOMEM||result == -ENOMEM)&&
291 size > (CFS_PAGE_SIZE / sizeof(*pages)) *
293 size = ((((size / 2) - 1) |
294 ~CFS_PAGE_MASK) + 1) &
296 CDEBUG(D_VFSTRACE, "DIO size now %u\n",
302 tot_bytes = page_count < 0 ? page_count : result;
303 GOTO(out, tot_bytes);
307 file_offset += result;
314 UNLOCK_INODE_MUTEX(inode);
319 rc = ptlrpc_set_wait(set);
322 } else if (rw == WRITE) {
323 lov_stripe_lock(lsm);
324 obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0);
325 lov_stripe_unlock(lsm);
329 capa_put(oinfo.oi_capa);
330 ptlrpc_set_destroy(set);
334 struct address_space_operations ll_aops = {
335 .readpage = ll_readpage,
336 // .readpages = ll_readpages,
337 .direct_IO = ll_direct_IO_26,
338 .writepage = ll_writepage_26,
339 .writepages = generic_writepages,
340 .set_page_dirty = ll_set_page_dirty,
342 .prepare_write = ll_prepare_write,
343 .commit_write = ll_commit_write,
344 .invalidatepage = ll_invalidatepage,
345 .releasepage = ll_releasepage,