xref: /linux/fs/gfs2/inode.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #include <linux/slab.h>
8 #include <linux/spinlock.h>
9 #include <linux/completion.h>
10 #include <linux/buffer_head.h>
11 #include <linux/namei.h>
12 #include <linux/mm.h>
13 #include <linux/cred.h>
14 #include <linux/xattr.h>
15 #include <linux/posix_acl.h>
16 #include <linux/gfs2_ondisk.h>
17 #include <linux/crc32.h>
18 #include <linux/iomap.h>
19 #include <linux/security.h>
20 #include <linux/uaccess.h>
21 
22 #include "gfs2.h"
23 #include "incore.h"
24 #include "acl.h"
25 #include "bmap.h"
26 #include "dir.h"
27 #include "xattr.h"
28 #include "glock.h"
29 #include "inode.h"
30 #include "meta_io.h"
31 #include "quota.h"
32 #include "rgrp.h"
33 #include "trans.h"
34 #include "util.h"
35 #include "super.h"
36 #include "glops.h"
37 
38 static int iget_test(struct inode *inode, void *opaque)
39 {
40 	u64 no_addr = *(u64 *)opaque;
41 
42 	return GFS2_I(inode)->i_no_addr == no_addr;
43 }
44 
45 static int iget_set(struct inode *inode, void *opaque)
46 {
47 	u64 no_addr = *(u64 *)opaque;
48 
49 	GFS2_I(inode)->i_no_addr = no_addr;
50 	inode->i_ino = no_addr;
51 	return 0;
52 }
53 
54 static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr)
55 {
56 	struct inode *inode;
57 
58 repeat:
59 	inode = iget5_locked(sb, no_addr, iget_test, iget_set, &no_addr);
60 	if (!inode)
61 		return inode;
62 	if (is_bad_inode(inode)) {
63 		iput(inode);
64 		goto repeat;
65 	}
66 	return inode;
67 }
68 
69 /**
70  * gfs2_set_iop - Sets inode operations
71  * @inode: The inode with correct i_mode filled in
72  *
73  * GFS2 lookup code fills in vfs inode contents based on info obtained
74  * from directory entry inside gfs2_inode_lookup().
75  */
76 
77 static void gfs2_set_iop(struct inode *inode)
78 {
79 	struct gfs2_sbd *sdp = GFS2_SB(inode);
80 	umode_t mode = inode->i_mode;
81 
82 	if (S_ISREG(mode)) {
83 		inode->i_op = &gfs2_file_iops;
84 		if (gfs2_localflocks(sdp))
85 			inode->i_fop = &gfs2_file_fops_nolock;
86 		else
87 			inode->i_fop = &gfs2_file_fops;
88 	} else if (S_ISDIR(mode)) {
89 		inode->i_op = &gfs2_dir_iops;
90 		if (gfs2_localflocks(sdp))
91 			inode->i_fop = &gfs2_dir_fops_nolock;
92 		else
93 			inode->i_fop = &gfs2_dir_fops;
94 	} else if (S_ISLNK(mode)) {
95 		inode->i_op = &gfs2_symlink_iops;
96 	} else {
97 		inode->i_op = &gfs2_file_iops;
98 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
99 	}
100 }
101 
102 /**
103  * gfs2_inode_lookup - Lookup an inode
104  * @sb: The super block
105  * @type: The type of the inode
106  * @no_addr: The inode number
107  * @no_formal_ino: The inode generation number
108  * @blktype: Requested block type (GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED;
109  *           GFS2_BLKST_FREE to indicate not to verify)
110  *
111  * If @type is DT_UNKNOWN, the inode type is fetched from disk.
112  *
113  * If @blktype is anything other than GFS2_BLKST_FREE (which is used as a
114  * placeholder because it doesn't otherwise make sense), the on-disk block type
115  * is verified to be @blktype.
116  *
117  * Returns: A VFS inode, or an error
118  */
119 
120 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
121 				u64 no_addr, u64 no_formal_ino,
122 				unsigned int blktype)
123 {
124 	struct inode *inode;
125 	struct gfs2_inode *ip;
126 	struct gfs2_glock *io_gl = NULL;
127 	struct gfs2_holder i_gh;
128 	int error;
129 
130 	gfs2_holder_mark_uninitialized(&i_gh);
131 	inode = gfs2_iget(sb, no_addr);
132 	if (!inode)
133 		return ERR_PTR(-ENOMEM);
134 
135 	ip = GFS2_I(inode);
136 
137 	if (inode->i_state & I_NEW) {
138 		struct gfs2_sbd *sdp = GFS2_SB(inode);
139 		ip->i_no_formal_ino = no_formal_ino;
140 
141 		error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
142 		if (unlikely(error))
143 			goto fail;
144 		flush_delayed_work(&ip->i_gl->gl_work);
145 
146 		error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
147 		if (unlikely(error))
148 			goto fail_put;
149 
150 		if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
151 			/*
152 			 * The GL_SKIP flag indicates to skip reading the inode
153 			 * block.  We read the inode with gfs2_inode_refresh
154 			 * after possibly checking the block type.
155 			 */
156 			error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE,
157 						   GL_SKIP, &i_gh);
158 			if (error)
159 				goto fail_put;
160 
161 			if (blktype != GFS2_BLKST_FREE) {
162 				error = gfs2_check_blk_type(sdp, no_addr,
163 							    blktype);
164 				if (error)
165 					goto fail_put;
166 			}
167 		}
168 
169 		glock_set_object(ip->i_gl, ip);
170 		set_bit(GIF_INVALID, &ip->i_flags);
171 		error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
172 		if (unlikely(error))
173 			goto fail_put;
174 		glock_set_object(ip->i_iopen_gh.gh_gl, ip);
175 		gfs2_glock_put(io_gl);
176 		io_gl = NULL;
177 
178 		if (type == DT_UNKNOWN) {
179 			/* Inode glock must be locked already */
180 			error = gfs2_inode_refresh(GFS2_I(inode));
181 			if (error)
182 				goto fail_refresh;
183 		} else {
184 			inode->i_mode = DT2IF(type);
185 		}
186 
187 		gfs2_set_iop(inode);
188 
189 		/* Lowest possible timestamp; will be overwritten in gfs2_dinode_in. */
190 		inode->i_atime.tv_sec = 1LL << (8 * sizeof(inode->i_atime.tv_sec) - 1);
191 		inode->i_atime.tv_nsec = 0;
192 
193 		unlock_new_inode(inode);
194 	}
195 
196 	if (gfs2_holder_initialized(&i_gh))
197 		gfs2_glock_dq_uninit(&i_gh);
198 	return inode;
199 
200 fail_refresh:
201 	ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
202 	glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
203 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
204 fail_put:
205 	if (io_gl)
206 		gfs2_glock_put(io_gl);
207 	glock_clear_object(ip->i_gl, ip);
208 	if (gfs2_holder_initialized(&i_gh))
209 		gfs2_glock_dq_uninit(&i_gh);
210 fail:
211 	iget_failed(inode);
212 	return ERR_PTR(error);
213 }
214 
215 struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
216 				  u64 *no_formal_ino, unsigned int blktype)
217 {
218 	struct super_block *sb = sdp->sd_vfs;
219 	struct inode *inode;
220 	int error;
221 
222 	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0, blktype);
223 	if (IS_ERR(inode))
224 		return inode;
225 
226 	/* Two extra checks for NFS only */
227 	if (no_formal_ino) {
228 		error = -ESTALE;
229 		if (GFS2_I(inode)->i_no_formal_ino != *no_formal_ino)
230 			goto fail_iput;
231 
232 		error = -EIO;
233 		if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
234 			goto fail_iput;
235 	}
236 	return inode;
237 
238 fail_iput:
239 	iput(inode);
240 	return ERR_PTR(error);
241 }
242 
243 
244 struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
245 {
246 	struct qstr qstr;
247 	struct inode *inode;
248 	gfs2_str2qstr(&qstr, name);
249 	inode = gfs2_lookupi(dip, &qstr, 1);
250 	/* gfs2_lookupi has inconsistent callers: vfs
251 	 * related routines expect NULL for no entry found,
252 	 * gfs2_lookup_simple callers expect ENOENT
253 	 * and do not check for NULL.
254 	 */
255 	if (inode == NULL)
256 		return ERR_PTR(-ENOENT);
257 	else
258 		return inode;
259 }
260 
261 
262 /**
263  * gfs2_lookupi - Look up a filename in a directory and return its inode
264  * @d_gh: An initialized holder for the directory glock
265  * @name: The name of the inode to look for
266  * @is_root: If 1, ignore the caller's permissions
267  * @i_gh: An uninitialized holder for the new inode glock
268  *
269  * This can be called via the VFS filldir function when NFS is doing
270  * a readdirplus and the inode which its intending to stat isn't
271  * already in cache. In this case we must not take the directory glock
272  * again, since the readdir call will have already taken that lock.
273  *
274  * Returns: errno
275  */
276 
277 struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
278 			   int is_root)
279 {
280 	struct super_block *sb = dir->i_sb;
281 	struct gfs2_inode *dip = GFS2_I(dir);
282 	struct gfs2_holder d_gh;
283 	int error = 0;
284 	struct inode *inode = NULL;
285 
286 	gfs2_holder_mark_uninitialized(&d_gh);
287 	if (!name->len || name->len > GFS2_FNAMESIZE)
288 		return ERR_PTR(-ENAMETOOLONG);
289 
290 	if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
291 	    (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
292 	     dir == d_inode(sb->s_root))) {
293 		igrab(dir);
294 		return dir;
295 	}
296 
297 	if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
298 		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
299 		if (error)
300 			return ERR_PTR(error);
301 	}
302 
303 	if (!is_root) {
304 		error = gfs2_permission(dir, MAY_EXEC);
305 		if (error)
306 			goto out;
307 	}
308 
309 	inode = gfs2_dir_search(dir, name, false);
310 	if (IS_ERR(inode))
311 		error = PTR_ERR(inode);
312 out:
313 	if (gfs2_holder_initialized(&d_gh))
314 		gfs2_glock_dq_uninit(&d_gh);
315 	if (error == -ENOENT)
316 		return NULL;
317 	return inode ? inode : ERR_PTR(error);
318 }
319 
320 /**
321  * create_ok - OK to create a new on-disk inode here?
322  * @dip:  Directory in which dinode is to be created
323  * @name:  Name of new dinode
324  * @mode:
325  *
326  * Returns: errno
327  */
328 
329 static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
330 		     umode_t mode)
331 {
332 	int error;
333 
334 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
335 	if (error)
336 		return error;
337 
338 	/*  Don't create entries in an unlinked directory  */
339 	if (!dip->i_inode.i_nlink)
340 		return -ENOENT;
341 
342 	if (dip->i_entries == (u32)-1)
343 		return -EFBIG;
344 	if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
345 		return -EMLINK;
346 
347 	return 0;
348 }
349 
350 static void munge_mode_uid_gid(const struct gfs2_inode *dip,
351 			       struct inode *inode)
352 {
353 	if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
354 	    (dip->i_inode.i_mode & S_ISUID) &&
355 	    !uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
356 		if (S_ISDIR(inode->i_mode))
357 			inode->i_mode |= S_ISUID;
358 		else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
359 			inode->i_mode &= ~07111;
360 		inode->i_uid = dip->i_inode.i_uid;
361 	} else
362 		inode->i_uid = current_fsuid();
363 
364 	if (dip->i_inode.i_mode & S_ISGID) {
365 		if (S_ISDIR(inode->i_mode))
366 			inode->i_mode |= S_ISGID;
367 		inode->i_gid = dip->i_inode.i_gid;
368 	} else
369 		inode->i_gid = current_fsgid();
370 }
371 
372 static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
373 {
374 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
375 	struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
376 	int error;
377 
378 	error = gfs2_quota_lock_check(ip, &ap);
379 	if (error)
380 		goto out;
381 
382 	error = gfs2_inplace_reserve(ip, &ap);
383 	if (error)
384 		goto out_quota;
385 
386 	error = gfs2_trans_begin(sdp, (*dblocks * RES_RG_BIT) + RES_STATFS + RES_QUOTA, 0);
387 	if (error)
388 		goto out_ipreserv;
389 
390 	error = gfs2_alloc_blocks(ip, &ip->i_no_addr, dblocks, 1, &ip->i_generation);
391 	ip->i_no_formal_ino = ip->i_generation;
392 	ip->i_inode.i_ino = ip->i_no_addr;
393 	ip->i_goal = ip->i_no_addr;
394 
395 	gfs2_trans_end(sdp);
396 
397 out_ipreserv:
398 	gfs2_inplace_release(ip);
399 out_quota:
400 	gfs2_quota_unlock(ip);
401 out:
402 	return error;
403 }
404 
405 static void gfs2_init_dir(struct buffer_head *dibh,
406 			  const struct gfs2_inode *parent)
407 {
408 	struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
409 	struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
410 
411 	gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
412 	dent->de_inum = di->di_num; /* already GFS2 endian */
413 	dent->de_type = cpu_to_be16(DT_DIR);
414 
415 	dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
416 	gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
417 	gfs2_inum_out(parent, dent);
418 	dent->de_type = cpu_to_be16(DT_DIR);
419 
420 }
421 
422 /**
423  * gfs2_init_xattr - Initialise an xattr block for a new inode
424  * @ip: The inode in question
425  *
426  * This sets up an empty xattr block for a new inode, ready to
427  * take any ACLs, LSM xattrs, etc.
428  */
429 
430 static void gfs2_init_xattr(struct gfs2_inode *ip)
431 {
432 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
433 	struct buffer_head *bh;
434 	struct gfs2_ea_header *ea;
435 
436 	bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
437 	gfs2_trans_add_meta(ip->i_gl, bh);
438 	gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
439 	gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
440 
441 	ea = GFS2_EA_BH2FIRST(bh);
442 	ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
443 	ea->ea_type = GFS2_EATYPE_UNUSED;
444 	ea->ea_flags = GFS2_EAFLAG_LAST;
445 
446 	brelse(bh);
447 }
448 
449 /**
450  * init_dinode - Fill in a new dinode structure
451  * @dip: The directory this inode is being created in
452  * @ip: The inode
453  * @symname: The symlink destination (if a symlink)
454  * @bhp: The buffer head (returned to caller)
455  *
456  */
457 
458 static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
459 			const char *symname)
460 {
461 	struct gfs2_dinode *di;
462 	struct buffer_head *dibh;
463 
464 	dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
465 	gfs2_trans_add_meta(ip->i_gl, dibh);
466 	di = (struct gfs2_dinode *)dibh->b_data;
467 	gfs2_dinode_out(ip, di);
468 
469 	di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
470 	di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
471 	di->__pad1 = 0;
472 	di->__pad2 = 0;
473 	di->__pad3 = 0;
474 	memset(&di->__pad4, 0, sizeof(di->__pad4));
475 	memset(&di->di_reserved, 0, sizeof(di->di_reserved));
476 	gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
477 
478 	switch(ip->i_inode.i_mode & S_IFMT) {
479 	case S_IFDIR:
480 		gfs2_init_dir(dibh, dip);
481 		break;
482 	case S_IFLNK:
483 		memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
484 		break;
485 	}
486 
487 	set_buffer_uptodate(dibh);
488 	brelse(dibh);
489 }
490 
491 /**
492  * gfs2_trans_da_blocks - Calculate number of blocks to link inode
493  * @dip: The directory we are linking into
494  * @da: The dir add information
495  * @nr_inodes: The number of inodes involved
496  *
497  * This calculate the number of blocks we need to reserve in a
498  * transaction to link @nr_inodes into a directory. In most cases
499  * @nr_inodes will be 2 (the directory plus the inode being linked in)
500  * but in case of rename, 4 may be required.
501  *
502  * Returns: Number of blocks
503  */
504 
505 static unsigned gfs2_trans_da_blks(const struct gfs2_inode *dip,
506 				   const struct gfs2_diradd *da,
507 				   unsigned nr_inodes)
508 {
509 	return da->nr_blocks + gfs2_rg_blocks(dip, da->nr_blocks) +
510 	       (nr_inodes * RES_DINODE) + RES_QUOTA + RES_STATFS;
511 }
512 
513 static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
514 		       struct gfs2_inode *ip, struct gfs2_diradd *da)
515 {
516 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
517 	struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
518 	int error;
519 
520 	if (da->nr_blocks) {
521 		error = gfs2_quota_lock_check(dip, &ap);
522 		if (error)
523 			goto fail_quota_locks;
524 
525 		error = gfs2_inplace_reserve(dip, &ap);
526 		if (error)
527 			goto fail_quota_locks;
528 
529 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 0);
530 		if (error)
531 			goto fail_ipreserv;
532 	} else {
533 		error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
534 		if (error)
535 			goto fail_quota_locks;
536 	}
537 
538 	error = gfs2_dir_add(&dip->i_inode, name, ip, da);
539 
540 	gfs2_trans_end(sdp);
541 fail_ipreserv:
542 	gfs2_inplace_release(dip);
543 fail_quota_locks:
544 	gfs2_quota_unlock(dip);
545 	return error;
546 }
547 
548 static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
549 		    void *fs_info)
550 {
551 	const struct xattr *xattr;
552 	int err = 0;
553 
554 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
555 		err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
556 				       xattr->value_len, 0,
557 				       GFS2_EATYPE_SECURITY);
558 		if (err < 0)
559 			break;
560 	}
561 	return err;
562 }
563 
564 /**
565  * gfs2_create_inode - Create a new inode
566  * @dir: The parent directory
567  * @dentry: The new dentry
568  * @file: If non-NULL, the file which is being opened
569  * @mode: The permissions on the new inode
570  * @dev: For device nodes, this is the device number
571  * @symname: For symlinks, this is the link destination
572  * @size: The initial size of the inode (ignored for directories)
573  *
574  * Returns: 0 on success, or error code
575  */
576 
577 static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
578 			     struct file *file,
579 			     umode_t mode, dev_t dev, const char *symname,
580 			     unsigned int size, int excl)
581 {
582 	const struct qstr *name = &dentry->d_name;
583 	struct posix_acl *default_acl, *acl;
584 	struct gfs2_holder ghs[2];
585 	struct inode *inode = NULL;
586 	struct gfs2_inode *dip = GFS2_I(dir), *ip;
587 	struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
588 	struct gfs2_glock *io_gl = NULL;
589 	int error, free_vfs_inode = 1;
590 	u32 aflags = 0;
591 	unsigned blocks = 1;
592 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
593 
594 	if (!name->len || name->len > GFS2_FNAMESIZE)
595 		return -ENAMETOOLONG;
596 
597 	error = gfs2_rsqa_alloc(dip);
598 	if (error)
599 		return error;
600 
601 	error = gfs2_rindex_update(sdp);
602 	if (error)
603 		return error;
604 
605 	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
606 	if (error)
607 		goto fail;
608 	gfs2_holder_mark_uninitialized(ghs + 1);
609 
610 	error = create_ok(dip, name, mode);
611 	if (error)
612 		goto fail_gunlock;
613 
614 	inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
615 	error = PTR_ERR(inode);
616 	if (!IS_ERR(inode)) {
617 		if (S_ISDIR(inode->i_mode)) {
618 			iput(inode);
619 			inode = ERR_PTR(-EISDIR);
620 			goto fail_gunlock;
621 		}
622 		d_instantiate(dentry, inode);
623 		error = 0;
624 		if (file) {
625 			if (S_ISREG(inode->i_mode))
626 				error = finish_open(file, dentry, gfs2_open_common);
627 			else
628 				error = finish_no_open(file, NULL);
629 		}
630 		gfs2_glock_dq_uninit(ghs);
631 		return error;
632 	} else if (error != -ENOENT) {
633 		goto fail_gunlock;
634 	}
635 
636 	error = gfs2_diradd_alloc_required(dir, name, &da);
637 	if (error < 0)
638 		goto fail_gunlock;
639 
640 	inode = new_inode(sdp->sd_vfs);
641 	error = -ENOMEM;
642 	if (!inode)
643 		goto fail_gunlock;
644 
645 	error = posix_acl_create(dir, &mode, &default_acl, &acl);
646 	if (error)
647 		goto fail_gunlock;
648 
649 	ip = GFS2_I(inode);
650 	error = gfs2_rsqa_alloc(ip);
651 	if (error)
652 		goto fail_free_acls;
653 
654 	inode->i_mode = mode;
655 	set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
656 	inode->i_rdev = dev;
657 	inode->i_size = size;
658 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
659 	gfs2_set_inode_blocks(inode, 1);
660 	munge_mode_uid_gid(dip, inode);
661 	check_and_update_goal(dip);
662 	ip->i_goal = dip->i_goal;
663 	ip->i_diskflags = 0;
664 	ip->i_eattr = 0;
665 	ip->i_height = 0;
666 	ip->i_depth = 0;
667 	ip->i_entries = 0;
668 	ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */
669 
670 	switch(mode & S_IFMT) {
671 	case S_IFREG:
672 		if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
673 		    gfs2_tune_get(sdp, gt_new_files_jdata))
674 			ip->i_diskflags |= GFS2_DIF_JDATA;
675 		gfs2_set_aops(inode);
676 		break;
677 	case S_IFDIR:
678 		ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
679 		ip->i_diskflags |= GFS2_DIF_JDATA;
680 		ip->i_entries = 2;
681 		break;
682 	}
683 
684 	/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
685 	if (dip->i_diskflags & GFS2_DIF_SYSTEM)
686 		ip->i_diskflags |= GFS2_DIF_SYSTEM;
687 
688 	gfs2_set_inode_flags(inode);
689 
690 	if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
691 	    (dip->i_diskflags & GFS2_DIF_TOPDIR))
692 		aflags |= GFS2_AF_ORLOV;
693 
694 	if (default_acl || acl)
695 		blocks++;
696 
697 	error = alloc_dinode(ip, aflags, &blocks);
698 	if (error)
699 		goto fail_free_inode;
700 
701 	gfs2_set_inode_blocks(inode, blocks);
702 
703 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
704 	if (error)
705 		goto fail_free_inode;
706 	flush_delayed_work(&ip->i_gl->gl_work);
707 	glock_set_object(ip->i_gl, ip);
708 
709 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
710 	if (error)
711 		goto fail_free_inode;
712 
713 	error = gfs2_trans_begin(sdp, blocks, 0);
714 	if (error)
715 		goto fail_gunlock2;
716 
717 	if (blocks > 1) {
718 		ip->i_eattr = ip->i_no_addr + 1;
719 		gfs2_init_xattr(ip);
720 	}
721 	init_dinode(dip, ip, symname);
722 	gfs2_trans_end(sdp);
723 
724 	error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
725 	if (error)
726 		goto fail_gunlock2;
727 
728 	BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags));
729 
730 	error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
731 	if (error)
732 		goto fail_gunlock2;
733 
734 	glock_set_object(ip->i_iopen_gh.gh_gl, ip);
735 	gfs2_glock_put(io_gl);
736 	gfs2_set_iop(inode);
737 	insert_inode_hash(inode);
738 
739 	free_vfs_inode = 0; /* After this point, the inode is no longer
740 			       considered free. Any failures need to undo
741 			       the gfs2 structures. */
742 	if (default_acl) {
743 		error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
744 		if (error)
745 			goto fail_gunlock3;
746 		posix_acl_release(default_acl);
747 		default_acl = NULL;
748 	}
749 	if (acl) {
750 		error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
751 		if (error)
752 			goto fail_gunlock3;
753 		posix_acl_release(acl);
754 		acl = NULL;
755 	}
756 
757 	error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
758 					     &gfs2_initxattrs, NULL);
759 	if (error)
760 		goto fail_gunlock3;
761 
762 	error = link_dinode(dip, name, ip, &da);
763 	if (error)
764 		goto fail_gunlock3;
765 
766 	mark_inode_dirty(inode);
767 	d_instantiate(dentry, inode);
768 	if (file) {
769 		file->f_mode |= FMODE_CREATED;
770 		error = finish_open(file, dentry, gfs2_open_common);
771 	}
772 	gfs2_glock_dq_uninit(ghs);
773 	gfs2_glock_dq_uninit(ghs + 1);
774 	clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
775 	return error;
776 
777 fail_gunlock3:
778 	glock_clear_object(io_gl, ip);
779 	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
780 	gfs2_glock_put(io_gl);
781 fail_gunlock2:
782 	if (io_gl)
783 		clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
784 fail_free_inode:
785 	if (ip->i_gl) {
786 		glock_clear_object(ip->i_gl, ip);
787 		gfs2_glock_put(ip->i_gl);
788 	}
789 	gfs2_rsqa_delete(ip, NULL);
790 fail_free_acls:
791 	posix_acl_release(default_acl);
792 	posix_acl_release(acl);
793 fail_gunlock:
794 	gfs2_dir_no_add(&da);
795 	gfs2_glock_dq_uninit(ghs);
796 	if (inode && !IS_ERR(inode)) {
797 		clear_nlink(inode);
798 		if (!free_vfs_inode)
799 			mark_inode_dirty(inode);
800 		set_bit(free_vfs_inode ? GIF_FREE_VFS_INODE : GIF_ALLOC_FAILED,
801 			&GFS2_I(inode)->i_flags);
802 		iput(inode);
803 	}
804 	if (gfs2_holder_initialized(ghs + 1))
805 		gfs2_glock_dq_uninit(ghs + 1);
806 fail:
807 	return error;
808 }
809 
810 /**
811  * gfs2_create - Create a file
812  * @dir: The directory in which to create the file
813  * @dentry: The dentry of the new file
814  * @mode: The mode of the new file
815  *
816  * Returns: errno
817  */
818 
819 static int gfs2_create(struct inode *dir, struct dentry *dentry,
820 		       umode_t mode, bool excl)
821 {
822 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
823 }
824 
825 /**
826  * __gfs2_lookup - Look up a filename in a directory and return its inode
827  * @dir: The directory inode
828  * @dentry: The dentry of the new inode
829  * @file: File to be opened
830  *
831  *
832  * Returns: errno
833  */
834 
835 static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
836 				    struct file *file)
837 {
838 	struct inode *inode;
839 	struct dentry *d;
840 	struct gfs2_holder gh;
841 	struct gfs2_glock *gl;
842 	int error;
843 
844 	inode = gfs2_lookupi(dir, &dentry->d_name, 0);
845 	if (inode == NULL) {
846 		d_add(dentry, NULL);
847 		return NULL;
848 	}
849 	if (IS_ERR(inode))
850 		return ERR_CAST(inode);
851 
852 	gl = GFS2_I(inode)->i_gl;
853 	error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
854 	if (error) {
855 		iput(inode);
856 		return ERR_PTR(error);
857 	}
858 
859 	d = d_splice_alias(inode, dentry);
860 	if (IS_ERR(d)) {
861 		gfs2_glock_dq_uninit(&gh);
862 		return d;
863 	}
864 	if (file && S_ISREG(inode->i_mode))
865 		error = finish_open(file, dentry, gfs2_open_common);
866 
867 	gfs2_glock_dq_uninit(&gh);
868 	if (error) {
869 		dput(d);
870 		return ERR_PTR(error);
871 	}
872 	return d;
873 }
874 
875 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
876 				  unsigned flags)
877 {
878 	return __gfs2_lookup(dir, dentry, NULL);
879 }
880 
881 /**
882  * gfs2_link - Link to a file
883  * @old_dentry: The inode to link
884  * @dir: Add link to this directory
885  * @dentry: The name of the link
886  *
887  * Link the inode in "old_dentry" into the directory "dir" with the
888  * name in "dentry".
889  *
890  * Returns: errno
891  */
892 
893 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
894 		     struct dentry *dentry)
895 {
896 	struct gfs2_inode *dip = GFS2_I(dir);
897 	struct gfs2_sbd *sdp = GFS2_SB(dir);
898 	struct inode *inode = d_inode(old_dentry);
899 	struct gfs2_inode *ip = GFS2_I(inode);
900 	struct gfs2_holder ghs[2];
901 	struct buffer_head *dibh;
902 	struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
903 	int error;
904 
905 	if (S_ISDIR(inode->i_mode))
906 		return -EPERM;
907 
908 	error = gfs2_rsqa_alloc(dip);
909 	if (error)
910 		return error;
911 
912 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
913 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
914 
915 	error = gfs2_glock_nq(ghs); /* parent */
916 	if (error)
917 		goto out_parent;
918 
919 	error = gfs2_glock_nq(ghs + 1); /* child */
920 	if (error)
921 		goto out_child;
922 
923 	error = -ENOENT;
924 	if (inode->i_nlink == 0)
925 		goto out_gunlock;
926 
927 	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
928 	if (error)
929 		goto out_gunlock;
930 
931 	error = gfs2_dir_check(dir, &dentry->d_name, NULL);
932 	switch (error) {
933 	case -ENOENT:
934 		break;
935 	case 0:
936 		error = -EEXIST;
937 	default:
938 		goto out_gunlock;
939 	}
940 
941 	error = -EINVAL;
942 	if (!dip->i_inode.i_nlink)
943 		goto out_gunlock;
944 	error = -EFBIG;
945 	if (dip->i_entries == (u32)-1)
946 		goto out_gunlock;
947 	error = -EPERM;
948 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
949 		goto out_gunlock;
950 	error = -EINVAL;
951 	if (!ip->i_inode.i_nlink)
952 		goto out_gunlock;
953 	error = -EMLINK;
954 	if (ip->i_inode.i_nlink == (u32)-1)
955 		goto out_gunlock;
956 
957 	error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
958 	if (error < 0)
959 		goto out_gunlock;
960 
961 	if (da.nr_blocks) {
962 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
963 		error = gfs2_quota_lock_check(dip, &ap);
964 		if (error)
965 			goto out_gunlock;
966 
967 		error = gfs2_inplace_reserve(dip, &ap);
968 		if (error)
969 			goto out_gunlock_q;
970 
971 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
972 		if (error)
973 			goto out_ipres;
974 	} else {
975 		error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
976 		if (error)
977 			goto out_ipres;
978 	}
979 
980 	error = gfs2_meta_inode_buffer(ip, &dibh);
981 	if (error)
982 		goto out_end_trans;
983 
984 	error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
985 	if (error)
986 		goto out_brelse;
987 
988 	gfs2_trans_add_meta(ip->i_gl, dibh);
989 	inc_nlink(&ip->i_inode);
990 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
991 	ihold(inode);
992 	d_instantiate(dentry, inode);
993 	mark_inode_dirty(inode);
994 
995 out_brelse:
996 	brelse(dibh);
997 out_end_trans:
998 	gfs2_trans_end(sdp);
999 out_ipres:
1000 	if (da.nr_blocks)
1001 		gfs2_inplace_release(dip);
1002 out_gunlock_q:
1003 	if (da.nr_blocks)
1004 		gfs2_quota_unlock(dip);
1005 out_gunlock:
1006 	gfs2_dir_no_add(&da);
1007 	gfs2_glock_dq(ghs + 1);
1008 out_child:
1009 	gfs2_glock_dq(ghs);
1010 out_parent:
1011 	gfs2_holder_uninit(ghs);
1012 	gfs2_holder_uninit(ghs + 1);
1013 	return error;
1014 }
1015 
1016 /*
1017  * gfs2_unlink_ok - check to see that a inode is still in a directory
1018  * @dip: the directory
1019  * @name: the name of the file
1020  * @ip: the inode
1021  *
1022  * Assumes that the lock on (at least) @dip is held.
1023  *
1024  * Returns: 0 if the parent/child relationship is correct, errno if it isn't
1025  */
1026 
1027 static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
1028 			  const struct gfs2_inode *ip)
1029 {
1030 	int error;
1031 
1032 	if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
1033 		return -EPERM;
1034 
1035 	if ((dip->i_inode.i_mode & S_ISVTX) &&
1036 	    !uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
1037 	    !uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
1038 		return -EPERM;
1039 
1040 	if (IS_APPEND(&dip->i_inode))
1041 		return -EPERM;
1042 
1043 	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
1044 	if (error)
1045 		return error;
1046 
1047 	return gfs2_dir_check(&dip->i_inode, name, ip);
1048 }
1049 
1050 /**
1051  * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
1052  * @dip: The parent directory
1053  * @name: The name of the entry in the parent directory
1054  * @inode: The inode to be removed
1055  *
1056  * Called with all the locks and in a transaction. This will only be
1057  * called for a directory after it has been checked to ensure it is empty.
1058  *
1059  * Returns: 0 on success, or an error
1060  */
1061 
1062 static int gfs2_unlink_inode(struct gfs2_inode *dip,
1063 			     const struct dentry *dentry)
1064 {
1065 	struct inode *inode = d_inode(dentry);
1066 	struct gfs2_inode *ip = GFS2_I(inode);
1067 	int error;
1068 
1069 	error = gfs2_dir_del(dip, dentry);
1070 	if (error)
1071 		return error;
1072 
1073 	ip->i_entries = 0;
1074 	inode->i_ctime = current_time(inode);
1075 	if (S_ISDIR(inode->i_mode))
1076 		clear_nlink(inode);
1077 	else
1078 		drop_nlink(inode);
1079 	mark_inode_dirty(inode);
1080 	if (inode->i_nlink == 0)
1081 		gfs2_unlink_di(inode);
1082 	return 0;
1083 }
1084 
1085 
1086 /**
1087  * gfs2_unlink - Unlink an inode (this does rmdir as well)
1088  * @dir: The inode of the directory containing the inode to unlink
1089  * @dentry: The file itself
1090  *
1091  * This routine uses the type of the inode as a flag to figure out
1092  * whether this is an unlink or an rmdir.
1093  *
1094  * Returns: errno
1095  */
1096 
1097 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1098 {
1099 	struct gfs2_inode *dip = GFS2_I(dir);
1100 	struct gfs2_sbd *sdp = GFS2_SB(dir);
1101 	struct inode *inode = d_inode(dentry);
1102 	struct gfs2_inode *ip = GFS2_I(inode);
1103 	struct gfs2_holder ghs[3];
1104 	struct gfs2_rgrpd *rgd;
1105 	int error;
1106 
1107 	error = gfs2_rindex_update(sdp);
1108 	if (error)
1109 		return error;
1110 
1111 	error = -EROFS;
1112 
1113 	gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1114 	gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1115 
1116 	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1117 	if (!rgd)
1118 		goto out_inodes;
1119 
1120 	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
1121 
1122 
1123 	error = gfs2_glock_nq(ghs); /* parent */
1124 	if (error)
1125 		goto out_parent;
1126 
1127 	error = gfs2_glock_nq(ghs + 1); /* child */
1128 	if (error)
1129 		goto out_child;
1130 
1131 	error = -ENOENT;
1132 	if (inode->i_nlink == 0)
1133 		goto out_rgrp;
1134 
1135 	if (S_ISDIR(inode->i_mode)) {
1136 		error = -ENOTEMPTY;
1137 		if (ip->i_entries > 2 || inode->i_nlink > 2)
1138 			goto out_rgrp;
1139 	}
1140 
1141 	error = gfs2_glock_nq(ghs + 2); /* rgrp */
1142 	if (error)
1143 		goto out_rgrp;
1144 
1145 	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1146 	if (error)
1147 		goto out_gunlock;
1148 
1149 	error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1150 	if (error)
1151 		goto out_gunlock;
1152 
1153 	error = gfs2_unlink_inode(dip, dentry);
1154 	gfs2_trans_end(sdp);
1155 
1156 out_gunlock:
1157 	gfs2_glock_dq(ghs + 2);
1158 out_rgrp:
1159 	gfs2_glock_dq(ghs + 1);
1160 out_child:
1161 	gfs2_glock_dq(ghs);
1162 out_parent:
1163 	gfs2_holder_uninit(ghs + 2);
1164 out_inodes:
1165 	gfs2_holder_uninit(ghs + 1);
1166 	gfs2_holder_uninit(ghs);
1167 	return error;
1168 }
1169 
1170 /**
1171  * gfs2_symlink - Create a symlink
1172  * @dir: The directory to create the symlink in
1173  * @dentry: The dentry to put the symlink in
1174  * @symname: The thing which the link points to
1175  *
1176  * Returns: errno
1177  */
1178 
1179 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
1180 			const char *symname)
1181 {
1182 	unsigned int size;
1183 
1184 	size = strlen(symname);
1185 	if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
1186 		return -ENAMETOOLONG;
1187 
1188 	return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
1189 }
1190 
1191 /**
1192  * gfs2_mkdir - Make a directory
1193  * @dir: The parent directory of the new one
1194  * @dentry: The dentry of the new directory
1195  * @mode: The mode of the new directory
1196  *
1197  * Returns: errno
1198  */
1199 
1200 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1201 {
1202 	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
1203 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
1204 }
1205 
1206 /**
1207  * gfs2_mknod - Make a special file
1208  * @dir: The directory in which the special file will reside
1209  * @dentry: The dentry of the special file
1210  * @mode: The mode of the special file
1211  * @dev: The device specification of the special file
1212  *
1213  */
1214 
1215 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
1216 		      dev_t dev)
1217 {
1218 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
1219 }
1220 
1221 /**
1222  * gfs2_atomic_open - Atomically open a file
1223  * @dir: The directory
1224  * @dentry: The proposed new entry
1225  * @file: The proposed new struct file
1226  * @flags: open flags
1227  * @mode: File mode
1228  *
1229  * Returns: error code or 0 for success
1230  */
1231 
1232 static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
1233 			    struct file *file, unsigned flags,
1234 			    umode_t mode)
1235 {
1236 	struct dentry *d;
1237 	bool excl = !!(flags & O_EXCL);
1238 
1239 	if (!d_in_lookup(dentry))
1240 		goto skip_lookup;
1241 
1242 	d = __gfs2_lookup(dir, dentry, file);
1243 	if (IS_ERR(d))
1244 		return PTR_ERR(d);
1245 	if (d != NULL)
1246 		dentry = d;
1247 	if (d_really_is_positive(dentry)) {
1248 		if (!(file->f_mode & FMODE_OPENED))
1249 			return finish_no_open(file, d);
1250 		dput(d);
1251 		return 0;
1252 	}
1253 
1254 	BUG_ON(d != NULL);
1255 
1256 skip_lookup:
1257 	if (!(flags & O_CREAT))
1258 		return -ENOENT;
1259 
1260 	return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl);
1261 }
1262 
1263 /*
1264  * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1265  * @this: move this
1266  * @to: to here
1267  *
1268  * Follow @to back to the root and make sure we don't encounter @this
1269  * Assumes we already hold the rename lock.
1270  *
1271  * Returns: errno
1272  */
1273 
1274 static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1275 {
1276 	struct inode *dir = &to->i_inode;
1277 	struct super_block *sb = dir->i_sb;
1278 	struct inode *tmp;
1279 	int error = 0;
1280 
1281 	igrab(dir);
1282 
1283 	for (;;) {
1284 		if (dir == &this->i_inode) {
1285 			error = -EINVAL;
1286 			break;
1287 		}
1288 		if (dir == d_inode(sb->s_root)) {
1289 			error = 0;
1290 			break;
1291 		}
1292 
1293 		tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1294 		if (!tmp) {
1295 			error = -ENOENT;
1296 			break;
1297 		}
1298 		if (IS_ERR(tmp)) {
1299 			error = PTR_ERR(tmp);
1300 			break;
1301 		}
1302 
1303 		iput(dir);
1304 		dir = tmp;
1305 	}
1306 
1307 	iput(dir);
1308 
1309 	return error;
1310 }
1311 
1312 /**
1313  * update_moved_ino - Update an inode that's being moved
1314  * @ip: The inode being moved
1315  * @ndip: The parent directory of the new filename
1316  * @dir_rename: True of ip is a directory
1317  *
1318  * Returns: errno
1319  */
1320 
1321 static int update_moved_ino(struct gfs2_inode *ip, struct gfs2_inode *ndip,
1322 			    int dir_rename)
1323 {
1324 	if (dir_rename)
1325 		return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1326 
1327 	ip->i_inode.i_ctime = current_time(&ip->i_inode);
1328 	mark_inode_dirty_sync(&ip->i_inode);
1329 	return 0;
1330 }
1331 
1332 
1333 /**
1334  * gfs2_rename - Rename a file
1335  * @odir: Parent directory of old file name
1336  * @odentry: The old dentry of the file
1337  * @ndir: Parent directory of new file name
1338  * @ndentry: The new dentry of the file
1339  *
1340  * Returns: errno
1341  */
1342 
1343 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1344 		       struct inode *ndir, struct dentry *ndentry)
1345 {
1346 	struct gfs2_inode *odip = GFS2_I(odir);
1347 	struct gfs2_inode *ndip = GFS2_I(ndir);
1348 	struct gfs2_inode *ip = GFS2_I(d_inode(odentry));
1349 	struct gfs2_inode *nip = NULL;
1350 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1351 	struct gfs2_holder ghs[5], r_gh;
1352 	struct gfs2_rgrpd *nrgd;
1353 	unsigned int num_gh;
1354 	int dir_rename = 0;
1355 	struct gfs2_diradd da = { .nr_blocks = 0, .save_loc = 0, };
1356 	unsigned int x;
1357 	int error;
1358 
1359 	gfs2_holder_mark_uninitialized(&r_gh);
1360 	if (d_really_is_positive(ndentry)) {
1361 		nip = GFS2_I(d_inode(ndentry));
1362 		if (ip == nip)
1363 			return 0;
1364 	}
1365 
1366 	error = gfs2_rindex_update(sdp);
1367 	if (error)
1368 		return error;
1369 
1370 	error = gfs2_rsqa_alloc(ndip);
1371 	if (error)
1372 		return error;
1373 
1374 	if (odip != ndip) {
1375 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1376 					   0, &r_gh);
1377 		if (error)
1378 			goto out;
1379 
1380 		if (S_ISDIR(ip->i_inode.i_mode)) {
1381 			dir_rename = 1;
1382 			/* don't move a directory into its subdir */
1383 			error = gfs2_ok_to_move(ip, ndip);
1384 			if (error)
1385 				goto out_gunlock_r;
1386 		}
1387 	}
1388 
1389 	num_gh = 1;
1390 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1391 	if (odip != ndip) {
1392 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1393 		num_gh++;
1394 	}
1395 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1396 	num_gh++;
1397 
1398 	if (nip) {
1399 		gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1400 		num_gh++;
1401 		/* grab the resource lock for unlink flag twiddling
1402 		 * this is the case of the target file already existing
1403 		 * so we unlink before doing the rename
1404 		 */
1405 		nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1406 		if (nrgd)
1407 			gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
1408 	}
1409 
1410 	for (x = 0; x < num_gh; x++) {
1411 		error = gfs2_glock_nq(ghs + x);
1412 		if (error)
1413 			goto out_gunlock;
1414 	}
1415 
1416 	error = -ENOENT;
1417 	if (ip->i_inode.i_nlink == 0)
1418 		goto out_gunlock;
1419 
1420 	/* Check out the old directory */
1421 
1422 	error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1423 	if (error)
1424 		goto out_gunlock;
1425 
1426 	/* Check out the new directory */
1427 
1428 	if (nip) {
1429 		error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1430 		if (error)
1431 			goto out_gunlock;
1432 
1433 		if (nip->i_inode.i_nlink == 0) {
1434 			error = -EAGAIN;
1435 			goto out_gunlock;
1436 		}
1437 
1438 		if (S_ISDIR(nip->i_inode.i_mode)) {
1439 			if (nip->i_entries < 2) {
1440 				gfs2_consist_inode(nip);
1441 				error = -EIO;
1442 				goto out_gunlock;
1443 			}
1444 			if (nip->i_entries > 2) {
1445 				error = -ENOTEMPTY;
1446 				goto out_gunlock;
1447 			}
1448 		}
1449 	} else {
1450 		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
1451 		if (error)
1452 			goto out_gunlock;
1453 
1454 		error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1455 		switch (error) {
1456 		case -ENOENT:
1457 			error = 0;
1458 			break;
1459 		case 0:
1460 			error = -EEXIST;
1461 		default:
1462 			goto out_gunlock;
1463 		};
1464 
1465 		if (odip != ndip) {
1466 			if (!ndip->i_inode.i_nlink) {
1467 				error = -ENOENT;
1468 				goto out_gunlock;
1469 			}
1470 			if (ndip->i_entries == (u32)-1) {
1471 				error = -EFBIG;
1472 				goto out_gunlock;
1473 			}
1474 			if (S_ISDIR(ip->i_inode.i_mode) &&
1475 			    ndip->i_inode.i_nlink == (u32)-1) {
1476 				error = -EMLINK;
1477 				goto out_gunlock;
1478 			}
1479 		}
1480 	}
1481 
1482 	/* Check out the dir to be renamed */
1483 
1484 	if (dir_rename) {
1485 		error = gfs2_permission(d_inode(odentry), MAY_WRITE);
1486 		if (error)
1487 			goto out_gunlock;
1488 	}
1489 
1490 	if (nip == NULL) {
1491 		error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name, &da);
1492 		if (error)
1493 			goto out_gunlock;
1494 	}
1495 
1496 	if (da.nr_blocks) {
1497 		struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
1498 		error = gfs2_quota_lock_check(ndip, &ap);
1499 		if (error)
1500 			goto out_gunlock;
1501 
1502 		error = gfs2_inplace_reserve(ndip, &ap);
1503 		if (error)
1504 			goto out_gunlock_q;
1505 
1506 		error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(ndip, &da, 4) +
1507 					 4 * RES_LEAF + 4, 0);
1508 		if (error)
1509 			goto out_ipreserv;
1510 	} else {
1511 		error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1512 					 5 * RES_LEAF + 4, 0);
1513 		if (error)
1514 			goto out_gunlock;
1515 	}
1516 
1517 	/* Remove the target file, if it exists */
1518 
1519 	if (nip)
1520 		error = gfs2_unlink_inode(ndip, ndentry);
1521 
1522 	error = update_moved_ino(ip, ndip, dir_rename);
1523 	if (error)
1524 		goto out_end_trans;
1525 
1526 	error = gfs2_dir_del(odip, odentry);
1527 	if (error)
1528 		goto out_end_trans;
1529 
1530 	error = gfs2_dir_add(ndir, &ndentry->d_name, ip, &da);
1531 	if (error)
1532 		goto out_end_trans;
1533 
1534 out_end_trans:
1535 	gfs2_trans_end(sdp);
1536 out_ipreserv:
1537 	if (da.nr_blocks)
1538 		gfs2_inplace_release(ndip);
1539 out_gunlock_q:
1540 	if (da.nr_blocks)
1541 		gfs2_quota_unlock(ndip);
1542 out_gunlock:
1543 	gfs2_dir_no_add(&da);
1544 	while (x--) {
1545 		gfs2_glock_dq(ghs + x);
1546 		gfs2_holder_uninit(ghs + x);
1547 	}
1548 out_gunlock_r:
1549 	if (gfs2_holder_initialized(&r_gh))
1550 		gfs2_glock_dq_uninit(&r_gh);
1551 out:
1552 	return error;
1553 }
1554 
1555 /**
1556  * gfs2_exchange - exchange two files
1557  * @odir: Parent directory of old file name
1558  * @odentry: The old dentry of the file
1559  * @ndir: Parent directory of new file name
1560  * @ndentry: The new dentry of the file
1561  * @flags: The rename flags
1562  *
1563  * Returns: errno
1564  */
1565 
1566 static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
1567 			 struct inode *ndir, struct dentry *ndentry,
1568 			 unsigned int flags)
1569 {
1570 	struct gfs2_inode *odip = GFS2_I(odir);
1571 	struct gfs2_inode *ndip = GFS2_I(ndir);
1572 	struct gfs2_inode *oip = GFS2_I(odentry->d_inode);
1573 	struct gfs2_inode *nip = GFS2_I(ndentry->d_inode);
1574 	struct gfs2_sbd *sdp = GFS2_SB(odir);
1575 	struct gfs2_holder ghs[5], r_gh;
1576 	unsigned int num_gh;
1577 	unsigned int x;
1578 	umode_t old_mode = oip->i_inode.i_mode;
1579 	umode_t new_mode = nip->i_inode.i_mode;
1580 	int error;
1581 
1582 	gfs2_holder_mark_uninitialized(&r_gh);
1583 	error = gfs2_rindex_update(sdp);
1584 	if (error)
1585 		return error;
1586 
1587 	if (odip != ndip) {
1588 		error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1589 					   0, &r_gh);
1590 		if (error)
1591 			goto out;
1592 
1593 		if (S_ISDIR(old_mode)) {
1594 			/* don't move a directory into its subdir */
1595 			error = gfs2_ok_to_move(oip, ndip);
1596 			if (error)
1597 				goto out_gunlock_r;
1598 		}
1599 
1600 		if (S_ISDIR(new_mode)) {
1601 			/* don't move a directory into its subdir */
1602 			error = gfs2_ok_to_move(nip, odip);
1603 			if (error)
1604 				goto out_gunlock_r;
1605 		}
1606 	}
1607 
1608 	num_gh = 1;
1609 	gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1610 	if (odip != ndip) {
1611 		gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1612 		num_gh++;
1613 	}
1614 	gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1615 	num_gh++;
1616 
1617 	gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1618 	num_gh++;
1619 
1620 	for (x = 0; x < num_gh; x++) {
1621 		error = gfs2_glock_nq(ghs + x);
1622 		if (error)
1623 			goto out_gunlock;
1624 	}
1625 
1626 	error = -ENOENT;
1627 	if (oip->i_inode.i_nlink == 0 || nip->i_inode.i_nlink == 0)
1628 		goto out_gunlock;
1629 
1630 	error = gfs2_unlink_ok(odip, &odentry->d_name, oip);
1631 	if (error)
1632 		goto out_gunlock;
1633 	error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1634 	if (error)
1635 		goto out_gunlock;
1636 
1637 	if (S_ISDIR(old_mode)) {
1638 		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
1639 		if (error)
1640 			goto out_gunlock;
1641 	}
1642 	if (S_ISDIR(new_mode)) {
1643 		error = gfs2_permission(ndentry->d_inode, MAY_WRITE);
1644 		if (error)
1645 			goto out_gunlock;
1646 	}
1647 	error = gfs2_trans_begin(sdp, 4 * RES_DINODE + 4 * RES_LEAF, 0);
1648 	if (error)
1649 		goto out_gunlock;
1650 
1651 	error = update_moved_ino(oip, ndip, S_ISDIR(old_mode));
1652 	if (error)
1653 		goto out_end_trans;
1654 
1655 	error = update_moved_ino(nip, odip, S_ISDIR(new_mode));
1656 	if (error)
1657 		goto out_end_trans;
1658 
1659 	error = gfs2_dir_mvino(ndip, &ndentry->d_name, oip,
1660 			       IF2DT(old_mode));
1661 	if (error)
1662 		goto out_end_trans;
1663 
1664 	error = gfs2_dir_mvino(odip, &odentry->d_name, nip,
1665 			       IF2DT(new_mode));
1666 	if (error)
1667 		goto out_end_trans;
1668 
1669 	if (odip != ndip) {
1670 		if (S_ISDIR(new_mode) && !S_ISDIR(old_mode)) {
1671 			inc_nlink(&odip->i_inode);
1672 			drop_nlink(&ndip->i_inode);
1673 		} else if (S_ISDIR(old_mode) && !S_ISDIR(new_mode)) {
1674 			inc_nlink(&ndip->i_inode);
1675 			drop_nlink(&odip->i_inode);
1676 		}
1677 	}
1678 	mark_inode_dirty(&ndip->i_inode);
1679 	if (odip != ndip)
1680 		mark_inode_dirty(&odip->i_inode);
1681 
1682 out_end_trans:
1683 	gfs2_trans_end(sdp);
1684 out_gunlock:
1685 	while (x--) {
1686 		gfs2_glock_dq(ghs + x);
1687 		gfs2_holder_uninit(ghs + x);
1688 	}
1689 out_gunlock_r:
1690 	if (gfs2_holder_initialized(&r_gh))
1691 		gfs2_glock_dq_uninit(&r_gh);
1692 out:
1693 	return error;
1694 }
1695 
1696 static int gfs2_rename2(struct inode *odir, struct dentry *odentry,
1697 			struct inode *ndir, struct dentry *ndentry,
1698 			unsigned int flags)
1699 {
1700 	flags &= ~RENAME_NOREPLACE;
1701 
1702 	if (flags & ~RENAME_EXCHANGE)
1703 		return -EINVAL;
1704 
1705 	if (flags & RENAME_EXCHANGE)
1706 		return gfs2_exchange(odir, odentry, ndir, ndentry, flags);
1707 
1708 	return gfs2_rename(odir, odentry, ndir, ndentry);
1709 }
1710 
1711 /**
1712  * gfs2_get_link - Follow a symbolic link
1713  * @dentry: The dentry of the link
1714  * @inode: The inode of the link
1715  * @done: destructor for return value
1716  *
1717  * This can handle symlinks of any size.
1718  *
1719  * Returns: 0 on success or error code
1720  */
1721 
1722 static const char *gfs2_get_link(struct dentry *dentry,
1723 				 struct inode *inode,
1724 				 struct delayed_call *done)
1725 {
1726 	struct gfs2_inode *ip = GFS2_I(inode);
1727 	struct gfs2_holder i_gh;
1728 	struct buffer_head *dibh;
1729 	unsigned int size;
1730 	char *buf;
1731 	int error;
1732 
1733 	if (!dentry)
1734 		return ERR_PTR(-ECHILD);
1735 
1736 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1737 	error = gfs2_glock_nq(&i_gh);
1738 	if (error) {
1739 		gfs2_holder_uninit(&i_gh);
1740 		return ERR_PTR(error);
1741 	}
1742 
1743 	size = (unsigned int)i_size_read(&ip->i_inode);
1744 	if (size == 0) {
1745 		gfs2_consist_inode(ip);
1746 		buf = ERR_PTR(-EIO);
1747 		goto out;
1748 	}
1749 
1750 	error = gfs2_meta_inode_buffer(ip, &dibh);
1751 	if (error) {
1752 		buf = ERR_PTR(error);
1753 		goto out;
1754 	}
1755 
1756 	buf = kzalloc(size + 1, GFP_NOFS);
1757 	if (!buf)
1758 		buf = ERR_PTR(-ENOMEM);
1759 	else
1760 		memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1761 	brelse(dibh);
1762 out:
1763 	gfs2_glock_dq_uninit(&i_gh);
1764 	if (!IS_ERR(buf))
1765 		set_delayed_call(done, kfree_link, buf);
1766 	return buf;
1767 }
1768 
1769 /**
1770  * gfs2_permission -
1771  * @inode: The inode
1772  * @mask: The mask to be tested
1773  * @flags: Indicates whether this is an RCU path walk or not
1774  *
1775  * This may be called from the VFS directly, or from within GFS2 with the
1776  * inode locked, so we look to see if the glock is already locked and only
1777  * lock the glock if its not already been done.
1778  *
1779  * Returns: errno
1780  */
1781 
1782 int gfs2_permission(struct inode *inode, int mask)
1783 {
1784 	struct gfs2_inode *ip;
1785 	struct gfs2_holder i_gh;
1786 	int error;
1787 
1788 	gfs2_holder_mark_uninitialized(&i_gh);
1789 	ip = GFS2_I(inode);
1790 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1791 		if (mask & MAY_NOT_BLOCK)
1792 			return -ECHILD;
1793 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1794 		if (error)
1795 			return error;
1796 	}
1797 
1798 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1799 		error = -EPERM;
1800 	else
1801 		error = generic_permission(inode, mask);
1802 	if (gfs2_holder_initialized(&i_gh))
1803 		gfs2_glock_dq_uninit(&i_gh);
1804 
1805 	return error;
1806 }
1807 
1808 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1809 {
1810 	setattr_copy(inode, attr);
1811 	mark_inode_dirty(inode);
1812 	return 0;
1813 }
1814 
1815 /**
1816  * gfs2_setattr_simple -
1817  * @ip:
1818  * @attr:
1819  *
1820  * Returns: errno
1821  */
1822 
1823 int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1824 {
1825 	int error;
1826 
1827 	if (current->journal_info)
1828 		return __gfs2_setattr_simple(inode, attr);
1829 
1830 	error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1831 	if (error)
1832 		return error;
1833 
1834 	error = __gfs2_setattr_simple(inode, attr);
1835 	gfs2_trans_end(GFS2_SB(inode));
1836 	return error;
1837 }
1838 
1839 static int setattr_chown(struct inode *inode, struct iattr *attr)
1840 {
1841 	struct gfs2_inode *ip = GFS2_I(inode);
1842 	struct gfs2_sbd *sdp = GFS2_SB(inode);
1843 	kuid_t ouid, nuid;
1844 	kgid_t ogid, ngid;
1845 	int error;
1846 	struct gfs2_alloc_parms ap;
1847 
1848 	ouid = inode->i_uid;
1849 	ogid = inode->i_gid;
1850 	nuid = attr->ia_uid;
1851 	ngid = attr->ia_gid;
1852 
1853 	if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
1854 		ouid = nuid = NO_UID_QUOTA_CHANGE;
1855 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
1856 		ogid = ngid = NO_GID_QUOTA_CHANGE;
1857 
1858 	error = gfs2_rsqa_alloc(ip);
1859 	if (error)
1860 		goto out;
1861 
1862 	error = gfs2_rindex_update(sdp);
1863 	if (error)
1864 		goto out;
1865 
1866 	error = gfs2_quota_lock(ip, nuid, ngid);
1867 	if (error)
1868 		goto out;
1869 
1870 	ap.target = gfs2_get_inode_blocks(&ip->i_inode);
1871 
1872 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1873 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1874 		error = gfs2_quota_check(ip, nuid, ngid, &ap);
1875 		if (error)
1876 			goto out_gunlock_q;
1877 	}
1878 
1879 	error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1880 	if (error)
1881 		goto out_gunlock_q;
1882 
1883 	error = gfs2_setattr_simple(inode, attr);
1884 	if (error)
1885 		goto out_end_trans;
1886 
1887 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
1888 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
1889 		gfs2_quota_change(ip, -(s64)ap.target, ouid, ogid);
1890 		gfs2_quota_change(ip, ap.target, nuid, ngid);
1891 	}
1892 
1893 out_end_trans:
1894 	gfs2_trans_end(sdp);
1895 out_gunlock_q:
1896 	gfs2_quota_unlock(ip);
1897 out:
1898 	return error;
1899 }
1900 
1901 /**
1902  * gfs2_setattr - Change attributes on an inode
1903  * @dentry: The dentry which is changing
1904  * @attr: The structure describing the change
1905  *
1906  * The VFS layer wants to change one or more of an inodes attributes.  Write
1907  * that change out to disk.
1908  *
1909  * Returns: errno
1910  */
1911 
1912 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1913 {
1914 	struct inode *inode = d_inode(dentry);
1915 	struct gfs2_inode *ip = GFS2_I(inode);
1916 	struct gfs2_holder i_gh;
1917 	int error;
1918 
1919 	error = gfs2_rsqa_alloc(ip);
1920 	if (error)
1921 		return error;
1922 
1923 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1924 	if (error)
1925 		return error;
1926 
1927 	error = -EPERM;
1928 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1929 		goto out;
1930 
1931 	error = setattr_prepare(dentry, attr);
1932 	if (error)
1933 		goto out;
1934 
1935 	if (attr->ia_valid & ATTR_SIZE)
1936 		error = gfs2_setattr_size(inode, attr->ia_size);
1937 	else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1938 		error = setattr_chown(inode, attr);
1939 	else {
1940 		error = gfs2_setattr_simple(inode, attr);
1941 		if (!error && attr->ia_valid & ATTR_MODE)
1942 			error = posix_acl_chmod(inode, inode->i_mode);
1943 	}
1944 
1945 out:
1946 	if (!error)
1947 		mark_inode_dirty(inode);
1948 	gfs2_glock_dq_uninit(&i_gh);
1949 	return error;
1950 }
1951 
1952 /**
1953  * gfs2_getattr - Read out an inode's attributes
1954  * @path: Object to query
1955  * @stat: The inode's stats
1956  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
1957  * @flags: AT_STATX_xxx setting
1958  *
1959  * This may be called from the VFS directly, or from within GFS2 with the
1960  * inode locked, so we look to see if the glock is already locked and only
1961  * lock the glock if its not already been done. Note that its the NFS
1962  * readdirplus operation which causes this to be called (from filldir)
1963  * with the glock already held.
1964  *
1965  * Returns: errno
1966  */
1967 
1968 static int gfs2_getattr(const struct path *path, struct kstat *stat,
1969 			u32 request_mask, unsigned int flags)
1970 {
1971 	struct inode *inode = d_inode(path->dentry);
1972 	struct gfs2_inode *ip = GFS2_I(inode);
1973 	struct gfs2_holder gh;
1974 	u32 gfsflags;
1975 	int error;
1976 
1977 	gfs2_holder_mark_uninitialized(&gh);
1978 	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1979 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1980 		if (error)
1981 			return error;
1982 	}
1983 
1984 	gfsflags = ip->i_diskflags;
1985 	if (gfsflags & GFS2_DIF_APPENDONLY)
1986 		stat->attributes |= STATX_ATTR_APPEND;
1987 	if (gfsflags & GFS2_DIF_IMMUTABLE)
1988 		stat->attributes |= STATX_ATTR_IMMUTABLE;
1989 
1990 	stat->attributes_mask |= (STATX_ATTR_APPEND |
1991 				  STATX_ATTR_COMPRESSED |
1992 				  STATX_ATTR_ENCRYPTED |
1993 				  STATX_ATTR_IMMUTABLE |
1994 				  STATX_ATTR_NODUMP);
1995 
1996 	generic_fillattr(inode, stat);
1997 
1998 	if (gfs2_holder_initialized(&gh))
1999 		gfs2_glock_dq_uninit(&gh);
2000 
2001 	return 0;
2002 }
2003 
2004 static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2005 		       u64 start, u64 len)
2006 {
2007 	struct gfs2_inode *ip = GFS2_I(inode);
2008 	struct gfs2_holder gh;
2009 	int ret;
2010 
2011 	inode_lock_shared(inode);
2012 
2013 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2014 	if (ret)
2015 		goto out;
2016 
2017 	ret = iomap_fiemap(inode, fieinfo, start, len, &gfs2_iomap_ops);
2018 
2019 	gfs2_glock_dq_uninit(&gh);
2020 
2021 out:
2022 	inode_unlock_shared(inode);
2023 	return ret;
2024 }
2025 
2026 loff_t gfs2_seek_data(struct file *file, loff_t offset)
2027 {
2028 	struct inode *inode = file->f_mapping->host;
2029 	struct gfs2_inode *ip = GFS2_I(inode);
2030 	struct gfs2_holder gh;
2031 	loff_t ret;
2032 
2033 	inode_lock_shared(inode);
2034 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2035 	if (!ret)
2036 		ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);
2037 	gfs2_glock_dq_uninit(&gh);
2038 	inode_unlock_shared(inode);
2039 
2040 	if (ret < 0)
2041 		return ret;
2042 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2043 }
2044 
2045 loff_t gfs2_seek_hole(struct file *file, loff_t offset)
2046 {
2047 	struct inode *inode = file->f_mapping->host;
2048 	struct gfs2_inode *ip = GFS2_I(inode);
2049 	struct gfs2_holder gh;
2050 	loff_t ret;
2051 
2052 	inode_lock_shared(inode);
2053 	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
2054 	if (!ret)
2055 		ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);
2056 	gfs2_glock_dq_uninit(&gh);
2057 	inode_unlock_shared(inode);
2058 
2059 	if (ret < 0)
2060 		return ret;
2061 	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
2062 }
2063 
2064 const struct inode_operations gfs2_file_iops = {
2065 	.permission = gfs2_permission,
2066 	.setattr = gfs2_setattr,
2067 	.getattr = gfs2_getattr,
2068 	.listxattr = gfs2_listxattr,
2069 	.fiemap = gfs2_fiemap,
2070 	.get_acl = gfs2_get_acl,
2071 	.set_acl = gfs2_set_acl,
2072 };
2073 
2074 const struct inode_operations gfs2_dir_iops = {
2075 	.create = gfs2_create,
2076 	.lookup = gfs2_lookup,
2077 	.link = gfs2_link,
2078 	.unlink = gfs2_unlink,
2079 	.symlink = gfs2_symlink,
2080 	.mkdir = gfs2_mkdir,
2081 	.rmdir = gfs2_unlink,
2082 	.mknod = gfs2_mknod,
2083 	.rename = gfs2_rename2,
2084 	.permission = gfs2_permission,
2085 	.setattr = gfs2_setattr,
2086 	.getattr = gfs2_getattr,
2087 	.listxattr = gfs2_listxattr,
2088 	.fiemap = gfs2_fiemap,
2089 	.get_acl = gfs2_get_acl,
2090 	.set_acl = gfs2_set_acl,
2091 	.atomic_open = gfs2_atomic_open,
2092 };
2093 
2094 const struct inode_operations gfs2_symlink_iops = {
2095 	.get_link = gfs2_get_link,
2096 	.permission = gfs2_permission,
2097 	.setattr = gfs2_setattr,
2098 	.getattr = gfs2_getattr,
2099 	.listxattr = gfs2_listxattr,
2100 	.fiemap = gfs2_fiemap,
2101 };
2102 
2103