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>
44 #include <asm/segment.h>
46 #include <linux/pagemap.h>
47 #include <linux/smp_lock.h>
49 #define DEBUG_SUBSYSTEM S_LLITE
51 //#include <lustre_mdc.h>
52 #include <lustre_lite.h>
53 #include "llite_internal.h"
54 #include <linux/lustre_compat25.h>
56 static int ll_writepage_26(struct page *page, struct writeback_control *wbc)
58 return ll_writepage(page);
61 /* It is safe to not check anything in invalidatepage/releasepage below
62 because they are run with page locked and all our io is happening with
64 #ifdef HAVE_INVALIDATEPAGE_RETURN_INT
65 static int ll_invalidatepage(struct page *page, unsigned long offset)
69 if (PagePrivate(page))
74 static void ll_invalidatepage(struct page *page, unsigned long offset)
76 if (offset == 0 && PagePrivate(page))
80 static int ll_releasepage(struct page *page, int gfp_mask)
82 if (PagePrivate(page))
87 static int ll_set_page_dirty(struct page *page)
89 struct ll_async_page *llap;
92 llap = llap_from_page(page, LLAP_ORIGIN_UNKNOWN);
94 RETURN(PTR_ERR(llap));
96 llap_write_pending(page->mapping->host, llap);
97 RETURN(__set_page_dirty_nobuffers(page));
100 #define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL
102 static inline int ll_get_user_pages(int rw, unsigned long user_addr,
103 size_t size, struct page ***pages)
105 int result = -ENOMEM;
108 /* set an arbitrary limit to prevent arithmetic overflow */
109 if (size > MAX_DIRECTIO_SIZE) {
114 page_count = (user_addr + size + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
115 page_count -= user_addr >> CFS_PAGE_SHIFT;
117 OBD_ALLOC_WAIT(*pages, page_count * sizeof(**pages));
119 down_read(¤t->mm->mmap_sem);
120 result = get_user_pages(current, current->mm, user_addr,
121 page_count, (rw == READ), 0, *pages,
123 up_read(¤t->mm->mmap_sem);
125 OBD_FREE(*pages, page_count * sizeof(**pages));
131 /* ll_free_user_pages - tear down page struct array
132 * @pages: array of page struct pointers underlying target buffer */
133 static void ll_free_user_pages(struct page **pages, int npages, int do_dirty)
137 for (i = 0; i < npages; i++) {
139 set_page_dirty_lock(pages[i]);
140 page_cache_release(pages[i]);
143 OBD_FREE(pages, npages * sizeof(*pages));
146 static ssize_t ll_direct_IO_26_seg(int rw, struct inode *inode,
147 struct address_space *mapping,
148 struct obd_info *oinfo,
149 struct ptlrpc_request_set *set,
150 size_t size, loff_t file_offset,
151 struct page **pages, int page_count)
153 struct brw_page *pga;
158 OBD_ALLOC(pga, sizeof(*pga) * page_count);
160 CDEBUG(D_VFSTRACE, "sizeof(*pga) = %u page_count = %u\n",
161 (int)sizeof(*pga), page_count);
165 for (i = 0, length = size; length > 0;
166 length -=pga[i].count, file_offset +=pga[i].count,i++) {/*i last!*/
167 pga[i].pg = pages[i];
168 pga[i].off = file_offset;
169 /* To the end of the page, or the length, whatever is less */
170 pga[i].count = min_t(int, CFS_PAGE_SIZE -
171 (file_offset & ~CFS_PAGE_MASK),
175 POISON_PAGE(pages[i], 0x0d);
178 rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
179 ll_i2dtexp(inode), oinfo, page_count,
184 OBD_FREE(pga, sizeof(*pga) * page_count);
188 /* This is the maximum size of a single O_DIRECT request, based on a 128kB
189 * kmalloc limit. We need to fit all of the brw_page structs, each one
190 * representing PAGE_SIZE worth of user data, into a single buffer, and
191 * then truncate this to be a full-sized RPC. This is 22MB for 4kB pages. */
192 #define MAX_DIO_SIZE ((128 * 1024 / sizeof(struct brw_page) * CFS_PAGE_SIZE) & \
193 ~(PTLRPC_MAX_BRW_SIZE - 1))
194 static ssize_t ll_direct_IO_26(int rw, struct kiocb *iocb,
195 const struct iovec *iov, loff_t file_offset,
196 unsigned long nr_segs)
198 struct file *file = iocb->ki_filp;
199 struct inode *inode = file->f_mapping->host;
200 ssize_t count = iov_length(iov, nr_segs), tot_bytes = 0;
201 struct ll_inode_info *lli = ll_i2info(inode);
202 struct lov_stripe_md *lsm = lli->lli_smd;
203 struct ptlrpc_request_set *set;
204 struct obd_info oinfo;
206 unsigned long seg = 0;
207 size_t size = MAX_DIO_SIZE;
211 if (!lli->lli_smd || !lli->lli_smd->lsm_object_id)
214 /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
215 if ((file_offset & ~CFS_PAGE_MASK) || (count & ~CFS_PAGE_MASK))
218 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p), size="LPSZ" (max %lu), "
219 "offset=%lld=%llx, pages "LPSZ" (max %lu)\n",
220 inode->i_ino, inode->i_generation, inode, count, MAX_DIO_SIZE,
221 file_offset, file_offset, count >> CFS_PAGE_SHIFT,
222 MAX_DIO_SIZE >> CFS_PAGE_SHIFT);
225 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_WRITE, count);
226 opc = CAPA_OPC_OSS_WRITE;
227 llap_write_pending(inode, NULL);
229 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRECT_READ, count);
230 opc = CAPA_OPC_OSS_RW;
233 /* Check that all user buffers are aligned as well */
234 for (seg = 0; seg < nr_segs; seg++) {
235 if (((unsigned long)iov[seg].iov_base & ~CFS_PAGE_MASK) ||
236 (iov[seg].iov_len & ~CFS_PAGE_MASK))
240 set = ptlrpc_prep_set();
244 ll_inode_fill_obdo(inode, rw, &oa);
247 oinfo.oi_capa = ll_osscapa_get(inode, opc);
249 /* need locking between buffered and direct access. and race with
250 *size changing by concurrent truncates and writes. */
252 LOCK_INODE_MUTEX(inode);
254 for (seg = 0; seg < nr_segs; seg++) {
255 size_t iov_left = iov[seg].iov_len;
256 unsigned long user_addr = (unsigned long)iov[seg].iov_base;
259 if (file_offset >= inode->i_size)
261 if (file_offset + iov_left > inode->i_size)
262 iov_left = inode->i_size - file_offset;
265 while (iov_left > 0) {
270 page_count = ll_get_user_pages(rw, user_addr,
273 LASSERT(page_count != 0);
274 if (page_count > 0) {
275 result = ll_direct_IO_26_seg(rw, inode,
281 ll_free_user_pages(pages, page_count, rw==READ);
285 if (page_count < 0 || result <= 0) {
286 /* If we can't allocate a large enough buffer
287 * for the request, shrink it to a smaller
288 * PAGE_SIZE multiple and try again.
289 * We should always be able to kmalloc for a
290 * page worth of page pointers = 4MB on i386. */
291 if ((page_count == -ENOMEM||result == -ENOMEM)&&
292 size > (CFS_PAGE_SIZE / sizeof(*pages)) *
294 size = ((((size / 2) - 1) |
295 ~CFS_PAGE_MASK) + 1) &
297 CDEBUG(D_VFSTRACE, "DIO size now %u\n",
303 tot_bytes = page_count < 0 ? page_count : result;
304 GOTO(out, tot_bytes);
308 file_offset += result;
315 UNLOCK_INODE_MUTEX(inode);
320 rc = ptlrpc_set_wait(set);
323 } else if (rw == WRITE) {
324 lov_stripe_lock(lsm);
325 obd_adjust_kms(ll_i2dtexp(inode), lsm, file_offset, 0);
326 lov_stripe_unlock(lsm);
330 capa_put(oinfo.oi_capa);
331 ptlrpc_set_destroy(set);
335 struct address_space_operations ll_aops = {
336 .readpage = ll_readpage,
337 // .readpages = ll_readpages,
338 .direct_IO = ll_direct_IO_26,
339 .writepage = ll_writepage_26,
340 .writepages = generic_writepages,
341 .set_page_dirty = ll_set_page_dirty,
343 .prepare_write = ll_prepare_write,
344 .commit_write = ll_commit_write,
345 .invalidatepage = ll_invalidatepage,
346 .releasepage = ll_releasepage,