1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * lustre/lib/fsfilt_extN.c
5 * Lustre filesystem abstraction routines
7 * Copyright (C) 2002, 2003 Cluster File Systems, Inc.
8 * Author: Andreas Dilger <adilger@clusterfs.com>
10 * This file is part of Lustre, http://www.lustre.org.
12 * Lustre is free software; you can redistribute it and/or
13 * modify it under the terms of version 2 of the GNU General Public
14 * License as published by the Free Software Foundation.
16 * Lustre is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with Lustre; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #define DEBUG_SUBSYSTEM S_FILTER
29 #include <linux/jbd.h>
30 #include <linux/slab.h>
31 #include <linux/pagemap.h>
32 #include <linux/quotaops.h>
33 #include <linux/extN_fs.h>
34 #include <linux/extN_jbd.h>
35 #include <linux/extN_xattr.h>
36 #include <linux/kp30.h>
37 #include <linux/lustre_fsfilt.h>
38 #include <linux/obd.h>
39 #include <linux/obd_class.h>
40 #include <linux/module.h>
42 static kmem_cache_t *fcb_cache;
43 static int fcb_cache_count;
45 struct fsfilt_cb_data {
46 struct journal_callback cb_jcb; /* data private to jbd */
47 fsfilt_cb_t cb_func; /* MDS/OBD completion function */
48 struct obd_device *cb_obd; /* MDS/OBD completion device */
49 __u64 cb_last_rcvd; /* MDS/OST last committed operation */
52 #define EXTN_XATTR_INDEX_LUSTRE 5
53 #define XATTR_LUSTRE_MDS_OBJID "system.lustre_mds_objid"
56 * We don't currently need any additional blocks for rmdir and
57 * unlink transactions because we are storing the OST oa_id inside
58 * the inode (which we will be changing anyways as part of this
61 static void *fsfilt_extN_start(struct inode *inode, int op)
63 /* For updates to the last recieved file */
64 int nblocks = EXTN_DATA_TRANS_BLOCKS;
69 case FSFILT_OP_UNLINK:
70 nblocks += EXTN_DELETE_TRANS_BLOCKS;
72 case FSFILT_OP_RENAME:
73 /* modify additional directory */
74 nblocks += EXTN_DATA_TRANS_BLOCKS;
76 case FSFILT_OP_SYMLINK:
77 /* additional block + block bitmap + GDT for long symlink */
80 case FSFILT_OP_CREATE:
83 /* modify one inode + block bitmap + GDT */
87 /* modify parent directory */
88 nblocks += EXTN_INDEX_EXTRA_TRANS_BLOCKS+EXTN_DATA_TRANS_BLOCKS;
90 case FSFILT_OP_SETATTR:
91 /* Setattr on inode */
94 default: CERROR("unknown transaction start op %d\n", op);
98 LASSERT(!current->journal_info);
100 handle = journal_start(EXTN_JOURNAL(inode), nblocks);
107 * Calculate the number of buffer credits needed to write multiple pages in
108 * a single extN transaction. No, this shouldn't be here, but as yet extN
109 * doesn't have a nice API for calculating this sort of thing in advance.
111 * See comment above extN_writepage_trans_blocks for details. We assume
112 * no data journaling is being done, but it does allow for all of the pages
113 * being non-contiguous. If we are guaranteed contiguous pages we could
114 * reduce the number of (d)indirect blocks a lot.
116 * With N blocks per page and P pages, for each inode we have at most:
118 * min(N*P, blocksize/4 + 1) dindirect blocks
121 * For the entire filesystem, we have at most:
122 * min(sum(nindir + P), ngroups) bitmap blocks (from the above)
123 * min(sum(nindir + P), gdblocks) group descriptor blocks (from the above)
124 * objcount inode blocks
126 * 2 * EXTN_SINGLEDATA_TRANS_BLOCKS for the quota files
128 * 1 EXTN_DATA_TRANS_BLOCKS for the last_rcvd update.
130 static int fsfilt_extN_credits_needed(int objcount, struct fsfilt_objinfo *fso)
132 struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
133 int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
134 int addrpp = EXTN_ADDR_PER_BLOCK(sb) * blockpp;
137 int needed = objcount + 1;
140 for (i = 0; i < objcount; i++, fso++) {
141 int nblocks = fso->fso_bufcnt * blockpp;
142 int ndindirect = min(nblocks, addrpp + 1);
143 int nindir = nblocks + ndindirect + 1;
145 nbitmaps += nindir + nblocks;
146 ngdblocks += nindir + nblocks;
151 /* Assumes extN and extN have same sb_info layout at the start. */
152 if (nbitmaps > EXTN_SB(sb)->s_groups_count)
153 nbitmaps = EXTN_SB(sb)->s_groups_count;
154 if (ngdblocks > EXTN_SB(sb)->s_gdb_count)
155 ngdblocks = EXTN_SB(sb)->s_gdb_count;
157 needed += nbitmaps + ngdblocks;
159 /* last_rcvd update */
160 needed += EXTN_DATA_TRANS_BLOCKS;
163 /* We assume that there will be 1 bit set in s_dquot.flags for each
164 * quota file that is active. This is at least true for now.
166 needed += hweight32(sb_any_quota_enabled(sb)) *
167 EXTN_SINGLEDATA_TRANS_BLOCKS;
173 /* We have to start a huge journal transaction here to hold all of the
174 * metadata for the pages being written here. This is necessitated by
175 * the fact that we do lots of prepare_write operations before we do
176 * any of the matching commit_write operations, so even if we split
177 * up to use "smaller" transactions none of them could complete until
178 * all of them were opened. By having a single journal transaction,
179 * we eliminate duplicate reservations for common blocks like the
180 * superblock and group descriptors or bitmaps.
182 * We will start the transaction here, but each prepare_write will
183 * add a refcount to the transaction, and each commit_write will
184 * remove a refcount. The transaction will be closed when all of
185 * the pages have been written.
187 static void *fsfilt_extN_brw_start(int objcount, struct fsfilt_objinfo *fso,
188 int niocount, struct niobuf_remote *nb)
195 LASSERT(!current->journal_info);
196 journal = EXTN_SB(fso->fso_dentry->d_inode->i_sb)->s_journal;
197 needed = fsfilt_extN_credits_needed(objcount, fso);
199 /* The number of blocks we could _possibly_ dirty can very large.
200 * We reduce our request if it is absurd (and we couldn't get that
201 * many credits for a single handle anyways).
203 * At some point we have to limit the size of I/Os sent at one time,
204 * increase the size of the journal, or we have to calculate the
205 * actual journal requirements more carefully by checking all of
206 * the blocks instead of being maximally pessimistic. It remains to
207 * be seen if this is a real problem or not.
209 if (needed > journal->j_max_transaction_buffers) {
210 CERROR("want too many journal credits (%d) using %d instead\n",
211 needed, journal->j_max_transaction_buffers);
212 needed = journal->j_max_transaction_buffers;
216 handle = journal_start(journal, needed);
219 CERROR("can't get handle for %d credits: rc = %ld\n", needed,
225 static int fsfilt_extN_commit(struct inode *inode, void *h /*, force_sync */)
228 handle_t *handle = h;
232 handle->h_sync = 1; /* recovery likes this */
236 rc = journal_stop(handle);
242 static int fsfilt_extN_setattr(struct dentry *dentry, void *handle,
245 struct inode *inode = dentry->d_inode;
250 /* A _really_ horrible hack to avoid removing the data stored
251 * in the block pointers; this is really the "small" stripe MD data.
252 * We can avoid further hackery by virtue of the MDS file size being
253 * zero all the time (which doesn't invoke block truncate at unlink
254 * time), so we assert we never change the MDS file size from zero.
256 if (iattr->ia_valid & ATTR_SIZE) {
257 CERROR("hmm, setting %*s file size to %lld\n",
258 dentry->d_name.len, dentry->d_name.name, iattr->ia_size);
259 LASSERT(iattr->ia_size == 0);
261 /* ATTR_SIZE would invoke truncate: clear it */
262 iattr->ia_valid &= ~ATTR_SIZE;
263 inode->i_size = iattr->ia_size;
265 /* make sure _something_ gets set - so new inode
266 * goes to disk (probably won't work over XFS
268 if (!iattr->ia_valid & ATTR_MODE) {
269 iattr->ia_valid |= ATTR_MODE;
270 iattr->ia_mode = inode->i_mode;
274 if (inode->i_op->setattr)
275 rc = inode->i_op->setattr(dentry, iattr);
277 rc = inode_setattr(inode, iattr);
284 static int fsfilt_extN_set_md(struct inode *inode, void *handle,
285 void *lmm, int lmm_size)
289 /* Nasty hack city - store stripe MD data in the block pointers if
290 * it will fit, because putting it in an EA currently kills the MDS
291 * performance. We'll fix this with "fast EAs" in the future.
293 if (lmm_size <= sizeof(EXTN_I(inode)->i_data) -
294 sizeof(EXTN_I(inode)->i_data[0])) {
295 /* XXX old_size is debugging only */
296 int old_size = EXTN_I(inode)->i_data[0];
298 LASSERT(old_size < sizeof(EXTN_I(inode)->i_data));
299 CERROR("setting EA on %lu again... interesting\n",
303 EXTN_I(inode)->i_data[0] = cpu_to_le32(lmm_size);
304 memcpy(&EXTN_I(inode)->i_data[1], lmm, lmm_size);
305 mark_inode_dirty(inode);
310 rc = extN_xattr_set(handle, inode, EXTN_XATTR_INDEX_LUSTRE,
311 XATTR_LUSTRE_MDS_OBJID, lmm, lmm_size, 0);
317 CERROR("error adding MD data to inode %lu: rc = %d\n",
322 static int fsfilt_extN_get_md(struct inode *inode, void *lmm, int lmm_size)
326 if (EXTN_I(inode)->i_data[0]) {
327 int size = le32_to_cpu(EXTN_I(inode)->i_data[0]);
328 LASSERT(size < sizeof(EXTN_I(inode)->i_data));
332 memcpy(lmm, &EXTN_I(inode)->i_data[1], size);
339 rc = extN_xattr_get(inode, EXTN_XATTR_INDEX_LUSTRE,
340 XATTR_LUSTRE_MDS_OBJID, lmm, lmm_size);
344 /* This gives us the MD size */
346 return (rc == -ENODATA) ? 0 : rc;
349 CDEBUG(D_INFO, "error getting EA %s from inode %lu: "
350 "rc = %d\n", XATTR_LUSTRE_MDS_OBJID, inode->i_ino, rc);
351 memset(lmm, 0, lmm_size);
352 return (rc == -ENODATA) ? 0 : rc;
358 static ssize_t fsfilt_extN_readpage(struct file *file, char *buf, size_t count,
361 struct inode *inode = file->f_dentry->d_inode;
364 if (S_ISREG(inode->i_mode))
365 rc = file->f_op->read(file, buf, count, off);
367 const int blkbits = inode->i_sb->s_blocksize_bits;
368 const int blksize = inode->i_sb->s_blocksize;
370 CDEBUG(D_EXT2, "reading "LPSZ" at dir %lu+%llu\n",
371 count, inode->i_ino, *off);
373 struct buffer_head *bh;
376 if (*off < inode->i_size) {
379 bh = extN_bread(NULL, inode, *off >> blkbits,
382 CDEBUG(D_EXT2, "read %u@%llu\n", blksize, *off);
385 memcpy(buf, bh->b_data, blksize);
388 /* XXX in theory we should just fake
389 * this buffer and continue like ext3,
390 * especially if this is a partial read
392 CERROR("error read dir %lu+%llu: %d\n",
393 inode->i_ino, *off, err);
398 struct extN_dir_entry_2 *fake = (void *)buf;
400 CDEBUG(D_EXT2, "fake %u@%llu\n", blksize, *off);
401 memset(fake, 0, sizeof(*fake));
402 fake->rec_len = cpu_to_le32(blksize);
414 static void fsfilt_extN_cb_func(struct journal_callback *jcb, int error)
416 struct fsfilt_cb_data *fcb = (struct fsfilt_cb_data *)jcb;
418 fcb->cb_func(fcb->cb_obd, fcb->cb_last_rcvd, error);
420 kmem_cache_free(fcb_cache, fcb);
424 static int fsfilt_extN_set_last_rcvd(struct obd_device *obd, __u64 last_rcvd,
425 void *handle, fsfilt_cb_t cb_func)
427 struct fsfilt_cb_data *fcb;
429 fcb = kmem_cache_alloc(fcb_cache, GFP_NOFS);
434 fcb->cb_func = cb_func;
436 fcb->cb_last_rcvd = last_rcvd;
438 CDEBUG(D_EXT2, "set callback for last_rcvd: "LPD64"\n", last_rcvd);
440 /* Note that an "incompatible pointer" warning here is OK for now */
441 journal_callback_set(handle, fsfilt_extN_cb_func,
442 (struct journal_callback *)fcb);
448 static int fsfilt_extN_journal_data(struct file *filp)
450 struct inode *inode = filp->f_dentry->d_inode;
452 EXTN_I(inode)->i_flags |= EXTN_JOURNAL_DATA_FL;
458 * We need to hack the return value for the free inode counts because
459 * the current EA code requires one filesystem block per inode with EAs,
460 * so it is possible to run out of blocks before we run out of inodes.
462 * This can be removed when the extN EA code is fixed.
464 static int fsfilt_extN_statfs(struct super_block *sb, struct obd_statfs *osfs)
467 int rc = vfs_statfs(sb, &sfs);
469 if (!rc && sfs.f_bfree < sfs.f_ffree)
470 sfs.f_ffree = sfs.f_bfree;
472 statfs_pack(osfs, &sfs);
476 static int fsfilt_extN_sync(struct super_block *sb)
478 return extN_force_commit(sb);
481 static struct fsfilt_operations fsfilt_extN_ops = {
483 fs_owner: THIS_MODULE,
484 fs_start: fsfilt_extN_start,
485 fs_brw_start: fsfilt_extN_brw_start,
486 fs_commit: fsfilt_extN_commit,
487 fs_setattr: fsfilt_extN_setattr,
488 fs_set_md: fsfilt_extN_set_md,
489 fs_get_md: fsfilt_extN_get_md,
490 fs_readpage: fsfilt_extN_readpage,
491 fs_journal_data: fsfilt_extN_journal_data,
492 fs_set_last_rcvd: fsfilt_extN_set_last_rcvd,
493 fs_statfs: fsfilt_extN_statfs,
494 fs_sync: fsfilt_extN_sync,
497 static int __init fsfilt_extN_init(void)
501 //rc = extN_xattr_register();
502 fcb_cache = kmem_cache_create("fsfilt_extN_fcb",
503 sizeof(struct fsfilt_cb_data), 0,
506 CERROR("error allocating fsfilt journal callback cache\n");
507 GOTO(out, rc = -ENOMEM);
510 rc = fsfilt_register_ops(&fsfilt_extN_ops);
513 kmem_cache_destroy(fcb_cache);
518 static void __exit fsfilt_extN_exit(void)
522 fsfilt_unregister_ops(&fsfilt_extN_ops);
523 rc = kmem_cache_destroy(fcb_cache);
525 if (rc || fcb_cache_count) {
526 CERROR("can't free fsfilt callback cache: count %d, rc = %d\n",
527 fcb_cache_count, rc);
530 //rc = extN_xattr_unregister();
533 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
534 MODULE_DESCRIPTION("Lustre extN Filesystem Helper v0.1");
535 MODULE_LICENSE("GPL");
537 module_init(fsfilt_extN_init);
538 module_exit(fsfilt_extN_exit);