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 *lli = ll_i2info(inode);
41 struct lov_stripe_md *md = lli->lli_smd;
44 struct io_cb_data *cbd = ll_init_cb();
52 pg.off = ((obd_off)page->index) << PAGE_SHIFT;
53 pg.flag = create ? OBD_BRW_CREATE : 0;
55 err = obd_brw(rw, ll_i2obdconn(inode), md, 1, &pg, ll_sync_io_cb, cbd);
60 /* returns the page unlocked, but with a reference */
61 static int ll_readpage(struct file *file, struct page *page)
63 struct inode *inode = page->mapping->host;
67 if (!PageLocked(page))
70 if (((inode->i_size + PAGE_SIZE - 1) >> PAGE_SHIFT) <= page->index) {
71 memset(kmap(page), 0, PAGE_SIZE);
73 GOTO(readpage_out, rc);
76 if (Page_Uptodate(page)) {
77 CERROR("Explain this please?\n");
78 GOTO(readpage_out, rc);
81 rc = ll_brw(OBD_BRW_READ, inode, page, 0);
86 SetPageUptodate(page);
92 static int ll_prepare_write(struct file *file, struct page *page, unsigned from,
95 struct inode *inode = page->mapping->host;
96 //obd_off offset = ((obd_off)page->index) << PAGE_SHIFT;
102 if (!PageLocked(page))
105 if (Page_Uptodate(page))
106 GOTO(prepare_done, rc);
108 memset(addr, 0, PAGE_SIZE);
110 /* We're completely overwriting an existing page, so _don't_ set it up
111 * to date until commit_write */
112 if (from == 0 && to == PAGE_SIZE)
115 /* 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 *lli = ll_i2info(inode);
157 struct lov_stripe_md *md = lli->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);
198 } /* ll_commit_write */
200 void ll_truncate(struct inode *inode)
202 struct obdo oa = {0};
203 struct lov_stripe_md *md = ll_i2info(inode)->lli_smd;
208 /* object not yet allocated */
209 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
213 CDEBUG(D_INFO, "calling punch for %ld (all bytes after %Ld)\n",
214 (long)oa.o_id, (unsigned long long)oa.o_size);
216 oa.o_id = md->lmd_object_id;
217 oa.o_valid = OBD_MD_FLID;
218 /* truncate == punch to/from start from/to end:
219 set end to -1 for that. */
220 err = obd_punch(ll_i2obdconn(inode), &oa, md, inode->i_size,
223 CERROR("obd_truncate fails (%d)\n", err);
225 /* This is done for us at the OST and MDS, but the
226 * updated timestamps are not sent back to us.
229 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
235 int ll_direct_IO(int rw, struct inode *inode, struct kiobuf *iobuf,
236 unsigned long blocknr, int blocksize)
238 obd_count bufs_per_obdo = iobuf->nr_pages;
239 struct ll_inode_info *lli = ll_i2info(inode);
240 struct lov_stripe_md *md = lli->lli_smd;
241 struct brw_page *pga;
244 struct io_cb_data *cbd = ll_init_cb();
250 if (blocksize != PAGE_SIZE) {
251 CERROR("direct_IO blocksize != PAGE_SIZE\n");
255 OBD_ALLOC(pga, sizeof(*pga) * bufs_per_obdo);
257 GOTO(out, rc = -ENOMEM);
259 /* NB: we can't use iobuf->maplist[i]->index for the offset
260 * instead of "blocknr" because ->index contains garbage.
262 for (i = 0; i < bufs_per_obdo; i++, blocknr++) {
263 pga[i].pg = iobuf->maplist[i];
264 pga[i].count = PAGE_SIZE;
265 pga[i].off = (obd_off)blocknr << PAGE_SHIFT;
266 pga[i].flag = OBD_BRW_CREATE;
269 if (!md || !md->lmd_object_id)
270 GOTO(out, rc = -ENOMEM);
272 rc = obd_brw(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
273 ll_i2obdconn(inode), md, bufs_per_obdo, pga,
276 rc = bufs_per_obdo * PAGE_SIZE;
279 OBD_FREE(pga, sizeof(*pga) * bufs_per_obdo);
284 int ll_flush_inode_pages(struct inode * inode)
286 obd_count bufs_per_obdo = 0;
287 obd_size *count = NULL;
288 obd_off *offset = NULL;
289 obd_flag *flags = NULL;
294 spin_lock(&pagecache_lock);
296 spin_unlock(&pagecache_lock);
299 OBD_ALLOC(count, sizeof(*count) * bufs_per_obdo);
300 OBD_ALLOC(offset, sizeof(*offset) * bufs_per_obdo);
301 OBD_ALLOC(flags, sizeof(*flags) * bufs_per_obdo);
302 if (!count || !offset || !flags)
303 GOTO(out, err=-ENOMEM);
306 for (i = 0 ; i < bufs_per_obdo ; i++) {
307 count[i] = PAGE_SIZE;
308 offset[i] = ((obd_off)(iobuf->maplist[i])->index) << PAGE_SHIFT;
309 flags[i] = OBD_BRW_CREATE;
312 err = obd_brw(OBD_BRW_WRITE, ll_i2obdconn(inode),
313 ll_i2info(inode)->lli_smd, bufs_per_obdo,
314 iobuf->maplist, count, offset, flags, NULL, NULL);
316 err = bufs_per_obdo * 4096;
319 OBD_FREE(flags, sizeof(*flags) * bufs_per_obdo);
320 OBD_FREE(count, sizeof(*count) * bufs_per_obdo);
321 OBD_FREE(offset, sizeof(*offset) * bufs_per_obdo);
327 struct address_space_operations ll_aops = {
328 readpage: ll_readpage,
329 writepage: ll_writepage,
330 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,4,17))
331 direct_IO: ll_direct_IO,
333 sync_page: block_sync_page,
334 prepare_write: ll_prepare_write,
335 commit_write: ll_commit_write,