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
6 * Copyright (C) 2002 Cluster File Systems, Inc.
9 #include <linux/config.h>
10 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/stat.h>
14 #include <linux/iobuf.h>
15 #include <linux/errno.h>
16 #include <linux/locks.h>
17 #include <linux/unistd.h>
18 #include <linux/version.h>
19 #include <asm/system.h>
20 #include <asm/uaccess.h>
23 #include <linux/stat.h>
24 #include <asm/uaccess.h>
25 #include <asm/segment.h>
27 #include <linux/pagemap.h>
28 #include <linux/smp_lock.h>
30 #define DEBUG_SUBSYSTEM S_LLITE
32 #include <linux/lustre_mds.h>
33 #include <linux/lustre_lite.h>
34 #include <linux/lustre_lib.h>
37 /* SYNCHRONOUS I/O to object storage for an inode */
38 static int ll_brw(int rw, struct inode *inode, struct page *page, int create)
40 struct ll_inode_info *lii = ll_i2info(inode);
41 struct lov_stripe_md *md = lii->lli_smd;
44 struct io_cb_data *cbd = ll_init_cb();
51 pg.off = ((obd_off)page->index) << PAGE_SHIFT;
52 pg.flag = create ? OBD_BRW_CREATE : 0;
54 err = obd_brw(rw, ll_i2obdconn(inode), md, 1, &pg, ll_sync_io_cb, cbd);
58 /* returns the page unlocked, but with a reference */
59 static int ll_readpage(struct file *file, struct page *page)
61 struct inode *inode = page->mapping->host;
65 if (!PageLocked(page))
68 if (((inode->i_size + PAGE_SIZE - 1) >> PAGE_SHIFT) <= page->index) {
69 memset(kmap(page), 0, PAGE_SIZE);
71 GOTO(readpage_out, rc);
74 if (Page_Uptodate(page)) {
75 CERROR("Explain this please?\n");
76 GOTO(readpage_out, rc);
79 rc = ll_brw(OBD_BRW_READ, inode, page, 0);
84 SetPageUptodate(page);
90 static int ll_prepare_write(struct file *file, struct page *page, unsigned from,
93 struct inode *inode = page->mapping->host;
94 //obd_off offset = ((obd_off)page->index) << PAGE_SHIFT;
100 if (!PageLocked(page))
103 if (Page_Uptodate(page))
104 GOTO(prepare_done, rc);
106 memset(addr, 0, PAGE_SIZE);
108 /* We're completely overwriting an existing page, so _don't_ set it up
109 * to date until commit_write */
110 if (from == 0 && to == PAGE_SIZE)
113 /* prepare write should not read what lies beyond the end of
117 rc = ll_brw(OBD_BRW_READ, inode, page, 0);
122 SetPageUptodate(page);
127 /* returns the page unlocked, but with a reference */
128 static int ll_writepage(struct page *page)
130 struct inode *inode = page->mapping->host;
134 if (!PageLocked(page))
137 err = ll_brw(OBD_BRW_WRITE, inode, page, 1);
139 //SetPageUptodate(page);
140 set_page_clean(page);
142 CERROR("ll_brw failure %d\n", err);
149 /* SYNCHRONOUS I/O to object storage for an inode -- object attr will be updated
151 static int ll_commit_write(struct file *file, struct page *page,
152 unsigned from, unsigned to)
155 struct inode *inode = page->mapping->host;
156 struct ll_inode_info *lii = ll_i2info(inode);
157 struct lov_stripe_md *md = lii->lli_smd;
161 struct io_cb_data *cbd = ll_init_cb();
165 pg.off = (((obd_off)page->index) << PAGE_SHIFT);
166 pg.flag = create ? OBD_BRW_CREATE : 0;
172 SetPageUptodate(page);
174 if (!PageLocked(page))
177 CDEBUG(D_INODE, "commit_page writing (at %d) to %d, count %Ld\n",
178 from, to, (unsigned long long)pg.count);
180 err = obd_brw(OBD_BRW_WRITE, ll_i2obdconn(inode), md,
181 1, &pg, ll_sync_io_cb, cbd);
184 iattr.ia_size = pg.off + pg.count;
185 if (iattr.ia_size > inode->i_size) {
186 /* do NOT truncate when writing in the middle of a file */
187 inode->i_size = iattr.ia_size;
188 iattr.ia_valid = ATTR_SIZE;
190 err = ll_inode_setattr(inode, &iattr, 0);
192 CERROR("failed - %d.\n", err);
199 } /* ll_commit_write */
201 void ll_truncate(struct inode *inode)
203 struct obdo oa = {0};
204 struct lov_stripe_md *md = ll_i2info(inode)->lli_smd;
209 /* object not yet allocated */
210 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
214 CDEBUG(D_INFO, "calling punch for %ld (all bytes after %Ld)\n",
215 (long)oa.o_id, (unsigned long long)oa.o_size);
217 oa.o_id = md->lmd_object_id;
218 oa.o_valid = OBD_MD_FLID;
219 /* truncate == punch to/from start from/to end:
220 set end to -1 for that. */
221 err = obd_punch(ll_i2obdconn(inode), &oa, md, inode->i_size,
224 CERROR("obd_truncate fails (%d)\n", err);
226 /* This is done for us at the OST and MDS, but the
227 * updated timestamps are not sent back to us.
230 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
236 int ll_direct_IO(int rw, struct inode *inode, struct kiobuf *iobuf,
237 unsigned long blocknr, int blocksize)
239 obd_count bufs_per_obdo = iobuf->nr_pages;
240 struct ll_inode_info *lii = ll_i2info(inode);
241 struct lov_stripe_md *md = lii->lli_smd;
242 struct brw_page *pga;
245 struct io_cb_data *cbd = ll_init_cb();
251 if (blocksize != PAGE_SIZE) {
252 CERROR("direct_IO blocksize != PAGE_SIZE\n");
256 OBD_ALLOC(pga, sizeof(*pga) * bufs_per_obdo);
258 GOTO(out, rc = -ENOMEM);
260 /* NB: we can't use iobuf->maplist[i]->index for the offset
261 * instead of "blocknr" because ->index contains garbage.
263 for (i = 0; i < bufs_per_obdo; i++, blocknr++) {
264 pga[i].pg = iobuf->maplist[i];
265 pga[i].count = PAGE_SIZE;
266 pga[i].off = (obd_off)blocknr << PAGE_SHIFT;
267 pga[i].flag = OBD_BRW_CREATE;
270 if (!md || !md->lmd_object_id)
271 GOTO(out, rc = -ENOMEM);
273 rc = obd_brw(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
274 ll_i2obdconn(inode), md, bufs_per_obdo, pga,
277 rc = bufs_per_obdo * PAGE_SIZE;
280 OBD_FREE(pga, sizeof(*pga) * bufs_per_obdo);
285 int ll_flush_inode_pages(struct inode * inode)
287 obd_count bufs_per_obdo = 0;
288 obd_size *count = NULL;
289 obd_off *offset = NULL;
290 obd_flag *flags = NULL;
295 spin_lock(&pagecache_lock);
297 spin_unlock(&pagecache_lock);
300 OBD_ALLOC(count, sizeof(*count) * bufs_per_obdo);
301 OBD_ALLOC(offset, sizeof(*offset) * bufs_per_obdo);
302 OBD_ALLOC(flags, sizeof(*flags) * bufs_per_obdo);
303 if (!count || !offset || !flags)
304 GOTO(out, err=-ENOMEM);
307 for (i = 0 ; i < bufs_per_obdo ; i++) {
308 count[i] = PAGE_SIZE;
309 offset[i] = ((obd_off)(iobuf->maplist[i])->index) << PAGE_SHIFT;
310 flags[i] = OBD_BRW_CREATE;
313 err = obd_brw(OBD_BRW_WRITE, ll_i2obdconn(inode),
314 ll_i2info(inode)->lli_smd, bufs_per_obdo,
315 iobuf->maplist, count, offset, flags, NULL, NULL);
317 err = bufs_per_obdo * 4096;
320 OBD_FREE(flags, sizeof(*flags) * bufs_per_obdo);
321 OBD_FREE(count, sizeof(*count) * bufs_per_obdo);
322 OBD_FREE(offset, sizeof(*offset) * bufs_per_obdo);
328 struct address_space_operations ll_aops = {
329 readpage: ll_readpage,
330 writepage: ll_writepage,
331 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,4,17))
332 direct_IO: ll_direct_IO,
334 sync_page: block_sync_page,
335 prepare_write: ll_prepare_write,
336 commit_write: ll_commit_write,