linux/fs/gfs2/inode.c
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   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
   4 *
   5 * This copyrighted material is made available to anyone wishing to use,
   6 * modify, copy, or redistribute it subject to the terms and conditions
   7 * of the GNU General Public License version 2.
   8 */
   9
  10#include <linux/slab.h>
  11#include <linux/spinlock.h>
  12#include <linux/completion.h>
  13#include <linux/buffer_head.h>
  14#include <linux/namei.h>
  15#include <linux/mm.h>
  16#include <linux/xattr.h>
  17#include <linux/posix_acl.h>
  18#include <linux/gfs2_ondisk.h>
  19#include <linux/crc32.h>
  20#include <linux/fiemap.h>
  21#include <linux/security.h>
  22#include <asm/uaccess.h>
  23
  24#include "gfs2.h"
  25#include "incore.h"
  26#include "acl.h"
  27#include "bmap.h"
  28#include "dir.h"
  29#include "xattr.h"
  30#include "glock.h"
  31#include "inode.h"
  32#include "meta_io.h"
  33#include "quota.h"
  34#include "rgrp.h"
  35#include "trans.h"
  36#include "util.h"
  37#include "super.h"
  38#include "glops.h"
  39
  40struct gfs2_skip_data {
  41        u64 no_addr;
  42        int skipped;
  43        int non_block;
  44};
  45
  46static int iget_test(struct inode *inode, void *opaque)
  47{
  48        struct gfs2_inode *ip = GFS2_I(inode);
  49        struct gfs2_skip_data *data = opaque;
  50
  51        if (ip->i_no_addr == data->no_addr) {
  52                if (data->non_block &&
  53                    inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)) {
  54                        data->skipped = 1;
  55                        return 0;
  56                }
  57                return 1;
  58        }
  59        return 0;
  60}
  61
  62static int iget_set(struct inode *inode, void *opaque)
  63{
  64        struct gfs2_inode *ip = GFS2_I(inode);
  65        struct gfs2_skip_data *data = opaque;
  66
  67        if (data->skipped)
  68                return -ENOENT;
  69        inode->i_ino = (unsigned long)(data->no_addr);
  70        ip->i_no_addr = data->no_addr;
  71        return 0;
  72}
  73
  74struct inode *gfs2_ilookup(struct super_block *sb, u64 no_addr, int non_block)
  75{
  76        unsigned long hash = (unsigned long)no_addr;
  77        struct gfs2_skip_data data;
  78
  79        data.no_addr = no_addr;
  80        data.skipped = 0;
  81        data.non_block = non_block;
  82        return ilookup5(sb, hash, iget_test, &data);
  83}
  84
  85static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr,
  86                               int non_block)
  87{
  88        struct gfs2_skip_data data;
  89        unsigned long hash = (unsigned long)no_addr;
  90
  91        data.no_addr = no_addr;
  92        data.skipped = 0;
  93        data.non_block = non_block;
  94        return iget5_locked(sb, hash, iget_test, iget_set, &data);
  95}
  96
  97/**
  98 * gfs2_set_iop - Sets inode operations
  99 * @inode: The inode with correct i_mode filled in
 100 *
 101 * GFS2 lookup code fills in vfs inode contents based on info obtained
 102 * from directory entry inside gfs2_inode_lookup().
 103 */
 104
 105static void gfs2_set_iop(struct inode *inode)
 106{
 107        struct gfs2_sbd *sdp = GFS2_SB(inode);
 108        umode_t mode = inode->i_mode;
 109
 110        if (S_ISREG(mode)) {
 111                inode->i_op = &gfs2_file_iops;
 112                if (gfs2_localflocks(sdp))
 113                        inode->i_fop = &gfs2_file_fops_nolock;
 114                else
 115                        inode->i_fop = &gfs2_file_fops;
 116        } else if (S_ISDIR(mode)) {
 117                inode->i_op = &gfs2_dir_iops;
 118                if (gfs2_localflocks(sdp))
 119                        inode->i_fop = &gfs2_dir_fops_nolock;
 120                else
 121                        inode->i_fop = &gfs2_dir_fops;
 122        } else if (S_ISLNK(mode)) {
 123                inode->i_op = &gfs2_symlink_iops;
 124        } else {
 125                inode->i_op = &gfs2_file_iops;
 126                init_special_inode(inode, inode->i_mode, inode->i_rdev);
 127        }
 128}
 129
 130/**
 131 * gfs2_inode_lookup - Lookup an inode
 132 * @sb: The super block
 133 * @no_addr: The inode number
 134 * @type: The type of the inode
 135 * non_block: Can we block on inodes that are being freed?
 136 *
 137 * Returns: A VFS inode, or an error
 138 */
 139
 140struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
 141                                u64 no_addr, u64 no_formal_ino, int non_block)
 142{
 143        struct inode *inode;
 144        struct gfs2_inode *ip;
 145        struct gfs2_glock *io_gl = NULL;
 146        int error;
 147
 148        inode = gfs2_iget(sb, no_addr, non_block);
 149        ip = GFS2_I(inode);
 150
 151        if (!inode)
 152                return ERR_PTR(-ENOBUFS);
 153
 154        if (inode->i_state & I_NEW) {
 155                struct gfs2_sbd *sdp = GFS2_SB(inode);
 156                ip->i_no_formal_ino = no_formal_ino;
 157
 158                error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
 159                if (unlikely(error))
 160                        goto fail;
 161                ip->i_gl->gl_object = ip;
 162
 163                error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
 164                if (unlikely(error))
 165                        goto fail_put;
 166
 167                set_bit(GIF_INVALID, &ip->i_flags);
 168                error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
 169                if (unlikely(error))
 170                        goto fail_iopen;
 171
 172                ip->i_iopen_gh.gh_gl->gl_object = ip;
 173                gfs2_glock_put(io_gl);
 174                io_gl = NULL;
 175
 176                if (type == DT_UNKNOWN) {
 177                        /* Inode glock must be locked already */
 178                        error = gfs2_inode_refresh(GFS2_I(inode));
 179                        if (error)
 180                                goto fail_refresh;
 181                } else {
 182                        inode->i_mode = DT2IF(type);
 183                }
 184
 185                gfs2_set_iop(inode);
 186                unlock_new_inode(inode);
 187        }
 188
 189        return inode;
 190
 191fail_refresh:
 192        ip->i_iopen_gh.gh_gl->gl_object = NULL;
 193        gfs2_glock_dq_uninit(&ip->i_iopen_gh);
 194fail_iopen:
 195        if (io_gl)
 196                gfs2_glock_put(io_gl);
 197fail_put:
 198        ip->i_gl->gl_object = NULL;
 199        gfs2_glock_put(ip->i_gl);
 200fail:
 201        iget_failed(inode);
 202        return ERR_PTR(error);
 203}
 204
 205struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
 206                                  u64 *no_formal_ino, unsigned int blktype)
 207{
 208        struct super_block *sb = sdp->sd_vfs;
 209        struct gfs2_holder i_gh;
 210        struct inode *inode = NULL;
 211        int error;
 212
 213        /* Must not read in block until block type is verified */
 214        error = gfs2_glock_nq_num(sdp, no_addr, &gfs2_inode_glops,
 215                                  LM_ST_EXCLUSIVE, GL_SKIP, &i_gh);
 216        if (error)
 217                return ERR_PTR(error);
 218
 219        error = gfs2_check_blk_type(sdp, no_addr, blktype);
 220        if (error)
 221                goto fail;
 222
 223        inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0, 1);
 224        if (IS_ERR(inode))
 225                goto fail;
 226
 227        /* Two extra checks for NFS only */
 228        if (no_formal_ino) {
 229                error = -ESTALE;
 230                if (GFS2_I(inode)->i_no_formal_ino != *no_formal_ino)
 231                        goto fail_iput;
 232
 233                error = -EIO;
 234                if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
 235                        goto fail_iput;
 236
 237                error = 0;
 238        }
 239
 240fail:
 241        gfs2_glock_dq_uninit(&i_gh);
 242        return error ? ERR_PTR(error) : inode;
 243fail_iput:
 244        iput(inode);
 245        goto fail;
 246}
 247
 248
 249struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
 250{
 251        struct qstr qstr;
 252        struct inode *inode;
 253        gfs2_str2qstr(&qstr, name);
 254        inode = gfs2_lookupi(dip, &qstr, 1);
 255        /* gfs2_lookupi has inconsistent callers: vfs
 256         * related routines expect NULL for no entry found,
 257         * gfs2_lookup_simple callers expect ENOENT
 258         * and do not check for NULL.
 259         */
 260        if (inode == NULL)
 261                return ERR_PTR(-ENOENT);
 262        else
 263                return inode;
 264}
 265
 266
 267/**
 268 * gfs2_lookupi - Look up a filename in a directory and return its inode
 269 * @d_gh: An initialized holder for the directory glock
 270 * @name: The name of the inode to look for
 271 * @is_root: If 1, ignore the caller's permissions
 272 * @i_gh: An uninitialized holder for the new inode glock
 273 *
 274 * This can be called via the VFS filldir function when NFS is doing
 275 * a readdirplus and the inode which its intending to stat isn't
 276 * already in cache. In this case we must not take the directory glock
 277 * again, since the readdir call will have already taken that lock.
 278 *
 279 * Returns: errno
 280 */
 281
 282struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
 283                           int is_root)
 284{
 285        struct super_block *sb = dir->i_sb;
 286        struct gfs2_inode *dip = GFS2_I(dir);
 287        struct gfs2_holder d_gh;
 288        int error = 0;
 289        struct inode *inode = NULL;
 290        int unlock = 0;
 291
 292        if (!name->len || name->len > GFS2_FNAMESIZE)
 293                return ERR_PTR(-ENAMETOOLONG);
 294
 295        if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
 296            (name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
 297             dir == sb->s_root->d_inode)) {
 298                igrab(dir);
 299                return dir;
 300        }
 301
 302        if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
 303                error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
 304                if (error)
 305                        return ERR_PTR(error);
 306                unlock = 1;
 307        }
 308
 309        if (!is_root) {
 310                error = gfs2_permission(dir, MAY_EXEC);
 311                if (error)
 312                        goto out;
 313        }
 314
 315        inode = gfs2_dir_search(dir, name);
 316        if (IS_ERR(inode))
 317                error = PTR_ERR(inode);
 318out:
 319        if (unlock)
 320                gfs2_glock_dq_uninit(&d_gh);
 321        if (error == -ENOENT)
 322                return NULL;
 323        return inode ? inode : ERR_PTR(error);
 324}
 325
 326/**
 327 * create_ok - OK to create a new on-disk inode here?
 328 * @dip:  Directory in which dinode is to be created
 329 * @name:  Name of new dinode
 330 * @mode:
 331 *
 332 * Returns: errno
 333 */
 334
 335static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
 336                     umode_t mode)
 337{
 338        int error;
 339
 340        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
 341        if (error)
 342                return error;
 343
 344        /*  Don't create entries in an unlinked directory  */
 345        if (!dip->i_inode.i_nlink)
 346                return -ENOENT;
 347
 348        error = gfs2_dir_check(&dip->i_inode, name, NULL);
 349        switch (error) {
 350        case -ENOENT:
 351                error = 0;
 352                break;
 353        case 0:
 354                return -EEXIST;
 355        default:
 356                return error;
 357        }
 358
 359        if (dip->i_entries == (u32)-1)
 360                return -EFBIG;
 361        if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
 362                return -EMLINK;
 363
 364        return 0;
 365}
 366
 367static void munge_mode_uid_gid(struct gfs2_inode *dip, umode_t *mode,
 368                               unsigned int *uid, unsigned int *gid)
 369{
 370        if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
 371            (dip->i_inode.i_mode & S_ISUID) && dip->i_inode.i_uid) {
 372                if (S_ISDIR(*mode))
 373                        *mode |= S_ISUID;
 374                else if (dip->i_inode.i_uid != current_fsuid())
 375                        *mode &= ~07111;
 376                *uid = dip->i_inode.i_uid;
 377        } else
 378                *uid = current_fsuid();
 379
 380        if (dip->i_inode.i_mode & S_ISGID) {
 381                if (S_ISDIR(*mode))
 382                        *mode |= S_ISGID;
 383                *gid = dip->i_inode.i_gid;
 384        } else
 385                *gid = current_fsgid();
 386}
 387
 388static int alloc_dinode(struct gfs2_inode *dip, u64 *no_addr, u64 *generation)
 389{
 390        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
 391        int error;
 392        int dblocks = 1;
 393
 394        error = gfs2_inplace_reserve(dip, RES_DINODE);
 395        if (error)
 396                goto out;
 397
 398        error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS, 0);
 399        if (error)
 400                goto out_ipreserv;
 401
 402        error = gfs2_alloc_blocks(dip, no_addr, &dblocks, 1, generation);
 403
 404        gfs2_trans_end(sdp);
 405
 406out_ipreserv:
 407        gfs2_inplace_release(dip);
 408out:
 409        return error;
 410}
 411
 412static void gfs2_init_dir(struct buffer_head *dibh,
 413                          const struct gfs2_inode *parent)
 414{
 415        struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
 416        struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
 417
 418        gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
 419        dent->de_inum = di->di_num; /* already GFS2 endian */
 420        dent->de_type = cpu_to_be16(DT_DIR);
 421
 422        dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
 423        gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
 424        gfs2_inum_out(parent, dent);
 425        dent->de_type = cpu_to_be16(DT_DIR);
 426        
 427}
 428
 429/**
 430 * init_dinode - Fill in a new dinode structure
 431 * @dip: The directory this inode is being created in
 432 * @gl: The glock covering the new inode
 433 * @inum: The inode number
 434 * @mode: The file permissions
 435 * @uid: The uid of the new inode
 436 * @gid: The gid of the new inode
 437 * @generation: The generation number of the new inode
 438 * @dev: The device number (if a device node)
 439 * @symname: The symlink destination (if a symlink)
 440 * @size: The inode size (ignored for directories)
 441 * @bhp: The buffer head (returned to caller)
 442 *
 443 */
 444
 445static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
 446                        const struct gfs2_inum_host *inum, umode_t mode,
 447                        unsigned int uid, unsigned int gid,
 448                        const u64 *generation, dev_t dev, const char *symname,
 449                        unsigned size, struct buffer_head **bhp)
 450{
 451        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
 452        struct gfs2_dinode *di;
 453        struct buffer_head *dibh;
 454        struct timespec tv = CURRENT_TIME;
 455
 456        dibh = gfs2_meta_new(gl, inum->no_addr);
 457        gfs2_trans_add_bh(gl, dibh, 1);
 458        gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
 459        gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
 460        di = (struct gfs2_dinode *)dibh->b_data;
 461
 462        di->di_num.no_formal_ino = cpu_to_be64(inum->no_formal_ino);
 463        di->di_num.no_addr = cpu_to_be64(inum->no_addr);
 464        di->di_mode = cpu_to_be32(mode);
 465        di->di_uid = cpu_to_be32(uid);
 466        di->di_gid = cpu_to_be32(gid);
 467        di->di_nlink = 0;
 468        di->di_size = cpu_to_be64(size);
 469        di->di_blocks = cpu_to_be64(1);
 470        di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(tv.tv_sec);
 471        di->di_major = cpu_to_be32(MAJOR(dev));
 472        di->di_minor = cpu_to_be32(MINOR(dev));
 473        di->di_goal_meta = di->di_goal_data = cpu_to_be64(inum->no_addr);
 474        di->di_generation = cpu_to_be64(*generation);
 475        di->di_flags = 0;
 476        di->__pad1 = 0;
 477        di->di_payload_format = cpu_to_be32(S_ISDIR(mode) ? GFS2_FORMAT_DE : 0);
 478        di->di_height = 0;
 479        di->__pad2 = 0;
 480        di->__pad3 = 0;
 481        di->di_depth = 0;
 482        di->di_entries = 0;
 483        memset(&di->__pad4, 0, sizeof(di->__pad4));
 484        di->di_eattr = 0;
 485        di->di_atime_nsec = cpu_to_be32(tv.tv_nsec);
 486        di->di_mtime_nsec = cpu_to_be32(tv.tv_nsec);
 487        di->di_ctime_nsec = cpu_to_be32(tv.tv_nsec);
 488        memset(&di->di_reserved, 0, sizeof(di->di_reserved));
 489
 490        switch(mode & S_IFMT) { 
 491        case S_IFREG:
 492                if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
 493                    gfs2_tune_get(sdp, gt_new_files_jdata))
 494                        di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
 495                break;
 496        case S_IFDIR:
 497                di->di_flags |= cpu_to_be32(dip->i_diskflags &
 498                                            GFS2_DIF_INHERIT_JDATA);
 499                di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
 500                di->di_size = cpu_to_be64(sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode));
 501                di->di_entries = cpu_to_be32(2);
 502                gfs2_init_dir(dibh, dip);
 503                break;
 504        case S_IFLNK:
 505                memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, size);
 506                break;
 507        }
 508
 509        set_buffer_uptodate(dibh);
 510
 511        *bhp = dibh;
 512}
 513
 514static int make_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
 515                       umode_t mode, const struct gfs2_inum_host *inum,
 516                       const u64 *generation, dev_t dev, const char *symname,
 517                       unsigned int size, struct buffer_head **bhp)
 518{
 519        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
 520        unsigned int uid, gid;
 521        int error;
 522
 523        munge_mode_uid_gid(dip, &mode, &uid, &gid);
 524        error = gfs2_rindex_update(sdp);
 525        if (error)
 526                return error;
 527
 528        error = gfs2_quota_lock(dip, uid, gid);
 529        if (error)
 530                return error;
 531
 532        error = gfs2_quota_check(dip, uid, gid);
 533        if (error)
 534                goto out_quota;
 535
 536        error = gfs2_trans_begin(sdp, RES_DINODE + RES_QUOTA, 0);
 537        if (error)
 538                goto out_quota;
 539
 540        init_dinode(dip, gl, inum, mode, uid, gid, generation, dev, symname, size, bhp);
 541        gfs2_quota_change(dip, +1, uid, gid);
 542        gfs2_trans_end(sdp);
 543
 544out_quota:
 545        gfs2_quota_unlock(dip);
 546        return error;
 547}
 548
 549static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
 550                       struct gfs2_inode *ip)
 551{
 552        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
 553        int alloc_required;
 554        struct buffer_head *dibh;
 555        int error;
 556
 557        error = gfs2_rindex_update(sdp);
 558        if (error)
 559                return error;
 560
 561        error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
 562        if (error)
 563                goto fail;
 564
 565        error = alloc_required = gfs2_diradd_alloc_required(&dip->i_inode, name);
 566        if (alloc_required < 0)
 567                goto fail_quota_locks;
 568        if (alloc_required) {
 569                error = gfs2_quota_check(dip, dip->i_inode.i_uid, dip->i_inode.i_gid);
 570                if (error)
 571                        goto fail_quota_locks;
 572
 573                error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres);
 574                if (error)
 575                        goto fail_quota_locks;
 576
 577                error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 578                                         dip->i_rgd->rd_length +
 579                                         2 * RES_DINODE +
 580                                         RES_STATFS + RES_QUOTA, 0);
 581                if (error)
 582                        goto fail_ipreserv;
 583        } else {
 584                error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
 585                if (error)
 586                        goto fail_quota_locks;
 587        }
 588
 589        error = gfs2_dir_add(&dip->i_inode, name, ip);
 590        if (error)
 591                goto fail_end_trans;
 592
 593        error = gfs2_meta_inode_buffer(ip, &dibh);
 594        if (error)
 595                goto fail_end_trans;
 596        set_nlink(&ip->i_inode, S_ISDIR(ip->i_inode.i_mode) ? 2 : 1);
 597        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 598        gfs2_dinode_out(ip, dibh->b_data);
 599        brelse(dibh);
 600        return 0;
 601
 602fail_end_trans:
 603        gfs2_trans_end(sdp);
 604
 605fail_ipreserv:
 606        if (alloc_required)
 607                gfs2_inplace_release(dip);
 608
 609fail_quota_locks:
 610        gfs2_quota_unlock(dip);
 611
 612fail:
 613        return error;
 614}
 615
 616static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
 617                    void *fs_info)
 618{
 619        const struct xattr *xattr;
 620        int err = 0;
 621
 622        for (xattr = xattr_array; xattr->name != NULL; xattr++) {
 623                err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
 624                                       xattr->value_len, 0,
 625                                       GFS2_EATYPE_SECURITY);
 626                if (err < 0)
 627                        break;
 628        }
 629        return err;
 630}
 631
 632static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip,
 633                              const struct qstr *qstr)
 634{
 635        return security_inode_init_security(&ip->i_inode, &dip->i_inode, qstr,
 636                                            &gfs2_initxattrs, NULL);
 637}
 638
 639/**
 640 * gfs2_create_inode - Create a new inode
 641 * @dir: The parent directory
 642 * @dentry: The new dentry
 643 * @mode: The permissions on the new inode
 644 * @dev: For device nodes, this is the device number
 645 * @symname: For symlinks, this is the link destination
 646 * @size: The initial size of the inode (ignored for directories)
 647 *
 648 * Returns: 0 on success, or error code
 649 */
 650
 651static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
 652                             umode_t mode, dev_t dev, const char *symname,
 653                             unsigned int size, int excl)
 654{
 655        const struct qstr *name = &dentry->d_name;
 656        struct gfs2_holder ghs[2];
 657        struct inode *inode = NULL;
 658        struct gfs2_inode *dip = GFS2_I(dir), *ip;
 659        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
 660        struct gfs2_inum_host inum = { .no_addr = 0, .no_formal_ino = 0 };
 661        int error;
 662        u64 generation;
 663        struct buffer_head *bh = NULL;
 664
 665        if (!name->len || name->len > GFS2_FNAMESIZE)
 666                return -ENAMETOOLONG;
 667
 668        /* We need a reservation to allocate the new dinode block. The
 669           directory ip temporarily points to the reservation, but this is
 670           being done to get a set of contiguous blocks for the new dinode.
 671           Since this is a create, we don't have a sizehint yet, so it will
 672           have to use the minimum reservation size. */
 673        error = gfs2_rs_alloc(dip);
 674        if (error)
 675                return error;
 676
 677        error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 678        if (error)
 679                goto fail;
 680
 681        error = create_ok(dip, name, mode);
 682        if ((error == -EEXIST) && S_ISREG(mode) && !excl) {
 683                inode = gfs2_lookupi(dir, &dentry->d_name, 0);
 684                gfs2_glock_dq_uninit(ghs);
 685                d_instantiate(dentry, inode);
 686                return IS_ERR(inode) ? PTR_ERR(inode) : 0;
 687        }
 688        if (error)
 689                goto fail_gunlock;
 690
 691        error = alloc_dinode(dip, &inum.no_addr, &generation);
 692        if (error)
 693                goto fail_gunlock;
 694        inum.no_formal_ino = generation;
 695
 696        error = gfs2_glock_nq_num(sdp, inum.no_addr, &gfs2_inode_glops,
 697                                  LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
 698        if (error)
 699                goto fail_gunlock;
 700
 701        error = make_dinode(dip, ghs[1].gh_gl, mode, &inum, &generation, dev, symname, size, &bh);
 702        if (error)
 703                goto fail_gunlock2;
 704
 705        inode = gfs2_inode_lookup(dir->i_sb, IF2DT(mode), inum.no_addr,
 706                                  inum.no_formal_ino, 0);
 707        if (IS_ERR(inode))
 708                goto fail_gunlock2;
 709
 710        ip = GFS2_I(inode);
 711        error = gfs2_inode_refresh(ip);
 712        if (error)
 713                goto fail_gunlock2;
 714
 715        error = gfs2_rs_alloc(ip);
 716        if (error)
 717                goto fail_gunlock2;
 718
 719        error = gfs2_acl_create(dip, inode);
 720        if (error)
 721                goto fail_gunlock2;
 722
 723        error = gfs2_security_init(dip, ip, name);
 724        if (error)
 725                goto fail_gunlock2;
 726
 727        error = link_dinode(dip, name, ip);
 728        if (error)
 729                goto fail_gunlock2;
 730
 731        if (bh)
 732                brelse(bh);
 733
 734        gfs2_trans_end(sdp);
 735        gfs2_inplace_release(dip);
 736        gfs2_quota_unlock(dip);
 737        mark_inode_dirty(inode);
 738        gfs2_glock_dq_uninit_m(2, ghs);
 739        d_instantiate(dentry, inode);
 740        return 0;
 741
 742fail_gunlock2:
 743        gfs2_glock_dq_uninit(ghs + 1);
 744fail_gunlock:
 745        gfs2_glock_dq_uninit(ghs);
 746        if (inode && !IS_ERR(inode)) {
 747                set_bit(GIF_ALLOC_FAILED, &GFS2_I(inode)->i_flags);
 748                iput(inode);
 749        }
 750fail:
 751        gfs2_rs_delete(dip);
 752        if (bh)
 753                brelse(bh);
 754        return error;
 755}
 756
 757/**
 758 * gfs2_create - Create a file
 759 * @dir: The directory in which to create the file
 760 * @dentry: The dentry of the new file
 761 * @mode: The mode of the new file
 762 *
 763 * Returns: errno
 764 */
 765
 766static int gfs2_create(struct inode *dir, struct dentry *dentry,
 767                       umode_t mode, bool excl)
 768{
 769        return gfs2_create_inode(dir, dentry, S_IFREG | mode, 0, NULL, 0, excl);
 770}
 771
 772/**
 773 * gfs2_lookup - Look up a filename in a directory and return its inode
 774 * @dir: The directory inode
 775 * @dentry: The dentry of the new inode
 776 * @nd: passed from Linux VFS, ignored by us
 777 *
 778 * Called by the VFS layer. Lock dir and call gfs2_lookupi()
 779 *
 780 * Returns: errno
 781 */
 782
 783static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
 784                                  unsigned int flags)
 785{
 786        struct inode *inode = gfs2_lookupi(dir, &dentry->d_name, 0);
 787        if (inode && !IS_ERR(inode)) {
 788                struct gfs2_glock *gl = GFS2_I(inode)->i_gl;
 789                struct gfs2_holder gh;
 790                int error;
 791                error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
 792                if (error) {
 793                        iput(inode);
 794                        return ERR_PTR(error);
 795                }
 796                gfs2_glock_dq_uninit(&gh);
 797        }
 798        return d_splice_alias(inode, dentry);
 799}
 800
 801/**
 802 * gfs2_link - Link to a file
 803 * @old_dentry: The inode to link
 804 * @dir: Add link to this directory
 805 * @dentry: The name of the link
 806 *
 807 * Link the inode in "old_dentry" into the directory "dir" with the
 808 * name in "dentry".
 809 *
 810 * Returns: errno
 811 */
 812
 813static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 814                     struct dentry *dentry)
 815{
 816        struct gfs2_inode *dip = GFS2_I(dir);
 817        struct gfs2_sbd *sdp = GFS2_SB(dir);
 818        struct inode *inode = old_dentry->d_inode;
 819        struct gfs2_inode *ip = GFS2_I(inode);
 820        struct gfs2_holder ghs[2];
 821        struct buffer_head *dibh;
 822        int alloc_required;
 823        int error;
 824
 825        if (S_ISDIR(inode->i_mode))
 826                return -EPERM;
 827
 828        error = gfs2_rs_alloc(dip);
 829        if (error)
 830                return error;
 831
 832        gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 833        gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 834
 835        error = gfs2_glock_nq(ghs); /* parent */
 836        if (error)
 837                goto out_parent;
 838
 839        error = gfs2_glock_nq(ghs + 1); /* child */
 840        if (error)
 841                goto out_child;
 842
 843        error = -ENOENT;
 844        if (inode->i_nlink == 0)
 845                goto out_gunlock;
 846
 847        error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
 848        if (error)
 849                goto out_gunlock;
 850
 851        error = gfs2_dir_check(dir, &dentry->d_name, NULL);
 852        switch (error) {
 853        case -ENOENT:
 854                break;
 855        case 0:
 856                error = -EEXIST;
 857        default:
 858                goto out_gunlock;
 859        }
 860
 861        error = -EINVAL;
 862        if (!dip->i_inode.i_nlink)
 863                goto out_gunlock;
 864        error = -EFBIG;
 865        if (dip->i_entries == (u32)-1)
 866                goto out_gunlock;
 867        error = -EPERM;
 868        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 869                goto out_gunlock;
 870        error = -EINVAL;
 871        if (!ip->i_inode.i_nlink)
 872                goto out_gunlock;
 873        error = -EMLINK;
 874        if (ip->i_inode.i_nlink == (u32)-1)
 875                goto out_gunlock;
 876
 877        alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
 878        if (error < 0)
 879                goto out_gunlock;
 880        error = 0;
 881
 882        if (alloc_required) {
 883                error = gfs2_quota_lock_check(dip);
 884                if (error)
 885                        goto out_gunlock;
 886
 887                error = gfs2_inplace_reserve(dip, sdp->sd_max_dirres);
 888                if (error)
 889                        goto out_gunlock_q;
 890
 891                error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 892                                         gfs2_rg_blocks(dip, sdp->sd_max_dirres) +
 893                                         2 * RES_DINODE + RES_STATFS +
 894                                         RES_QUOTA, 0);
 895                if (error)
 896                        goto out_ipres;
 897        } else {
 898                error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
 899                if (error)
 900                        goto out_ipres;
 901        }
 902
 903        error = gfs2_meta_inode_buffer(ip, &dibh);
 904        if (error)
 905                goto out_end_trans;
 906
 907        error = gfs2_dir_add(dir, &dentry->d_name, ip);
 908        if (error)
 909                goto out_brelse;
 910
 911        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 912        inc_nlink(&ip->i_inode);
 913        ip->i_inode.i_ctime = CURRENT_TIME;
 914        ihold(inode);
 915        d_instantiate(dentry, inode);
 916        mark_inode_dirty(inode);
 917
 918out_brelse:
 919        brelse(dibh);
 920out_end_trans:
 921        gfs2_trans_end(sdp);
 922out_ipres:
 923        if (alloc_required)
 924                gfs2_inplace_release(dip);
 925out_gunlock_q:
 926        if (alloc_required)
 927                gfs2_quota_unlock(dip);
 928out_gunlock:
 929        gfs2_glock_dq(ghs + 1);
 930out_child:
 931        gfs2_glock_dq(ghs);
 932out_parent:
 933        gfs2_holder_uninit(ghs);
 934        gfs2_holder_uninit(ghs + 1);
 935        return error;
 936}
 937
 938/*
 939 * gfs2_unlink_ok - check to see that a inode is still in a directory
 940 * @dip: the directory
 941 * @name: the name of the file
 942 * @ip: the inode
 943 *
 944 * Assumes that the lock on (at least) @dip is held.
 945 *
 946 * Returns: 0 if the parent/child relationship is correct, errno if it isn't
 947 */
 948
 949static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
 950                          const struct gfs2_inode *ip)
 951{
 952        int error;
 953
 954        if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
 955                return -EPERM;
 956
 957        if ((dip->i_inode.i_mode & S_ISVTX) &&
 958            dip->i_inode.i_uid != current_fsuid() &&
 959            ip->i_inode.i_uid != current_fsuid() && !capable(CAP_FOWNER))
 960                return -EPERM;
 961
 962        if (IS_APPEND(&dip->i_inode))
 963                return -EPERM;
 964
 965        error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
 966        if (error)
 967                return error;
 968
 969        error = gfs2_dir_check(&dip->i_inode, name, ip);
 970        if (error)
 971                return error;
 972
 973        return 0;
 974}
 975
 976/**
 977 * gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
 978 * @dip: The parent directory
 979 * @name: The name of the entry in the parent directory
 980 * @bh: The inode buffer for the inode to be removed
 981 * @inode: The inode to be removed
 982 *
 983 * Called with all the locks and in a transaction. This will only be
 984 * called for a directory after it has been checked to ensure it is empty.
 985 *
 986 * Returns: 0 on success, or an error
 987 */
 988
 989static int gfs2_unlink_inode(struct gfs2_inode *dip,
 990                             const struct dentry *dentry,
 991                             struct buffer_head *bh)
 992{
 993        struct inode *inode = dentry->d_inode;
 994        struct gfs2_inode *ip = GFS2_I(inode);
 995        int error;
 996
 997        error = gfs2_dir_del(dip, dentry);
 998        if (error)
 999                return error;
1000
1001        ip->i_entries = 0;
1002        inode->i_ctime = CURRENT_TIME;
1003        if (S_ISDIR(inode->i_mode))
1004                clear_nlink(inode);
1005        else
1006                drop_nlink(inode);
1007        mark_inode_dirty(inode);
1008        if (inode->i_nlink == 0)
1009                gfs2_unlink_di(inode);
1010        return 0;
1011}
1012
1013
1014/**
1015 * gfs2_unlink - Unlink an inode (this does rmdir as well)
1016 * @dir: The inode of the directory containing the inode to unlink
1017 * @dentry: The file itself
1018 *
1019 * This routine uses the type of the inode as a flag to figure out
1020 * whether this is an unlink or an rmdir.
1021 *
1022 * Returns: errno
1023 */
1024
1025static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
1026{
1027        struct gfs2_inode *dip = GFS2_I(dir);
1028        struct gfs2_sbd *sdp = GFS2_SB(dir);
1029        struct inode *inode = dentry->d_inode;
1030        struct gfs2_inode *ip = GFS2_I(inode);
1031        struct buffer_head *bh;
1032        struct gfs2_holder ghs[3];
1033        struct gfs2_rgrpd *rgd;
1034        int error;
1035
1036        error = gfs2_rindex_update(sdp);
1037        if (error)
1038                return error;
1039
1040        error = -EROFS;
1041
1042        gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1043        gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
1044
1045        rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1046        if (!rgd)
1047                goto out_inodes;
1048
1049        gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
1050
1051
1052        error = gfs2_glock_nq(ghs); /* parent */
1053        if (error)
1054                goto out_parent;
1055
1056        error = gfs2_glock_nq(ghs + 1); /* child */
1057        if (error)
1058                goto out_child;
1059
1060        error = -ENOENT;
1061        if (inode->i_nlink == 0)
1062                goto out_rgrp;
1063
1064        if (S_ISDIR(inode->i_mode)) {
1065                error = -ENOTEMPTY;
1066                if (ip->i_entries > 2 || inode->i_nlink > 2)
1067                        goto out_rgrp;
1068        }
1069
1070        error = gfs2_glock_nq(ghs + 2); /* rgrp */
1071        if (error)
1072                goto out_rgrp;
1073
1074        error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
1075        if (error)
1076                goto out_gunlock;
1077
1078        error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
1079        if (error)
1080                goto out_gunlock;
1081
1082        error = gfs2_meta_inode_buffer(ip, &bh);
1083        if (error)
1084                goto out_end_trans;
1085
1086        error = gfs2_unlink_inode(dip, dentry, bh);
1087        brelse(bh);
1088
1089out_end_trans:
1090        gfs2_trans_end(sdp);
1091out_gunlock:
1092        gfs2_glock_dq(ghs + 2);
1093out_rgrp:
1094        gfs2_glock_dq(ghs + 1);
1095out_child:
1096        gfs2_glock_dq(ghs);
1097out_parent:
1098        gfs2_holder_uninit(ghs + 2);
1099out_inodes:
1100        gfs2_holder_uninit(ghs + 1);
1101        gfs2_holder_uninit(ghs);
1102        return error;
1103}
1104
1105/**
1106 * gfs2_symlink - Create a symlink
1107 * @dir: The directory to create the symlink in
1108 * @dentry: The dentry to put the symlink in
1109 * @symname: The thing which the link points to
1110 *
1111 * Returns: errno
1112 */
1113
1114static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
1115                        const char *symname)
1116{
1117        struct gfs2_sbd *sdp = GFS2_SB(dir);
1118        unsigned int size;
1119
1120        size = strlen(symname);
1121        if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
1122                return -ENAMETOOLONG;
1123
1124        return gfs2_create_inode(dir, dentry, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
1125}
1126
1127/**
1128 * gfs2_mkdir - Make a directory
1129 * @dir: The parent directory of the new one
1130 * @dentry: The dentry of the new directory
1131 * @mode: The mode of the new directory
1132 *
1133 * Returns: errno
1134 */
1135
1136static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1137{
1138        return gfs2_create_inode(dir, dentry, S_IFDIR | mode, 0, NULL, 0, 0);
1139}
1140
1141/**
1142 * gfs2_mknod - Make a special file
1143 * @dir: The directory in which the special file will reside
1144 * @dentry: The dentry of the special file
1145 * @mode: The mode of the special file
1146 * @dev: The device specification of the special file
1147 *
1148 */
1149
1150static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
1151                      dev_t dev)
1152{
1153        return gfs2_create_inode(dir, dentry, mode, dev, NULL, 0, 0);
1154}
1155
1156/*
1157 * gfs2_ok_to_move - check if it's ok to move a directory to another directory
1158 * @this: move this
1159 * @to: to here
1160 *
1161 * Follow @to back to the root and make sure we don't encounter @this
1162 * Assumes we already hold the rename lock.
1163 *
1164 * Returns: errno
1165 */
1166
1167static int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
1168{
1169        struct inode *dir = &to->i_inode;
1170        struct super_block *sb = dir->i_sb;
1171        struct inode *tmp;
1172        int error = 0;
1173
1174        igrab(dir);
1175
1176        for (;;) {
1177                if (dir == &this->i_inode) {
1178                        error = -EINVAL;
1179                        break;
1180                }
1181                if (dir == sb->s_root->d_inode) {
1182                        error = 0;
1183                        break;
1184                }
1185
1186                tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
1187                if (IS_ERR(tmp)) {
1188                        error = PTR_ERR(tmp);
1189                        break;
1190                }
1191
1192                iput(dir);
1193                dir = tmp;
1194        }
1195
1196        iput(dir);
1197
1198        return error;
1199}
1200
1201/**
1202 * gfs2_rename - Rename a file
1203 * @odir: Parent directory of old file name
1204 * @odentry: The old dentry of the file
1205 * @ndir: Parent directory of new file name
1206 * @ndentry: The new dentry of the file
1207 *
1208 * Returns: errno
1209 */
1210
1211static int gfs2_rename(struct inode *odir, struct dentry *odentry,
1212                       struct inode *ndir, struct dentry *ndentry)
1213{
1214        struct gfs2_inode *odip = GFS2_I(odir);
1215        struct gfs2_inode *ndip = GFS2_I(ndir);
1216        struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
1217        struct gfs2_inode *nip = NULL;
1218        struct gfs2_sbd *sdp = GFS2_SB(odir);
1219        struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, };
1220        struct gfs2_rgrpd *nrgd;
1221        unsigned int num_gh;
1222        int dir_rename = 0;
1223        int alloc_required = 0;
1224        unsigned int x;
1225        int error;
1226
1227        if (ndentry->d_inode) {
1228                nip = GFS2_I(ndentry->d_inode);
1229                if (ip == nip)
1230                        return 0;
1231        }
1232
1233        error = gfs2_rindex_update(sdp);
1234        if (error)
1235                return error;
1236
1237        error = gfs2_rs_alloc(ndip);
1238        if (error)
1239                return error;
1240
1241        if (odip != ndip) {
1242                error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
1243                                           0, &r_gh);
1244                if (error)
1245                        goto out;
1246
1247                if (S_ISDIR(ip->i_inode.i_mode)) {
1248                        dir_rename = 1;
1249                        /* don't move a dirctory into it's subdir */
1250                        error = gfs2_ok_to_move(ip, ndip);
1251                        if (error)
1252                                goto out_gunlock_r;
1253                }
1254        }
1255
1256        num_gh = 1;
1257        gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
1258        if (odip != ndip) {
1259                gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1260                num_gh++;
1261        }
1262        gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1263        num_gh++;
1264
1265        if (nip) {
1266                gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
1267                num_gh++;
1268                /* grab the resource lock for unlink flag twiddling 
1269                 * this is the case of the target file already existing
1270                 * so we unlink before doing the rename
1271                 */
1272                nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
1273                if (nrgd)
1274                        gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
1275        }
1276
1277        for (x = 0; x < num_gh; x++) {
1278                error = gfs2_glock_nq(ghs + x);
1279                if (error)
1280                        goto out_gunlock;
1281        }
1282
1283        error = -ENOENT;
1284        if (ip->i_inode.i_nlink == 0)
1285                goto out_gunlock;
1286
1287        /* Check out the old directory */
1288
1289        error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
1290        if (error)
1291                goto out_gunlock;
1292
1293        /* Check out the new directory */
1294
1295        if (nip) {
1296                error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
1297                if (error)
1298                        goto out_gunlock;
1299
1300                if (nip->i_inode.i_nlink == 0) {
1301                        error = -EAGAIN;
1302                        goto out_gunlock;
1303                }
1304
1305                if (S_ISDIR(nip->i_inode.i_mode)) {
1306                        if (nip->i_entries < 2) {
1307                                gfs2_consist_inode(nip);
1308                                error = -EIO;
1309                                goto out_gunlock;
1310                        }
1311                        if (nip->i_entries > 2) {
1312                                error = -ENOTEMPTY;
1313                                goto out_gunlock;
1314                        }
1315                }
1316        } else {
1317                error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
1318                if (error)
1319                        goto out_gunlock;
1320
1321                error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
1322                switch (error) {
1323                case -ENOENT:
1324                        error = 0;
1325                        break;
1326                case 0:
1327                        error = -EEXIST;
1328                default:
1329                        goto out_gunlock;
1330                };
1331
1332                if (odip != ndip) {
1333                        if (!ndip->i_inode.i_nlink) {
1334                                error = -ENOENT;
1335                                goto out_gunlock;
1336                        }
1337                        if (ndip->i_entries == (u32)-1) {
1338                                error = -EFBIG;
1339                                goto out_gunlock;
1340                        }
1341                        if (S_ISDIR(ip->i_inode.i_mode) &&
1342                            ndip->i_inode.i_nlink == (u32)-1) {
1343                                error = -EMLINK;
1344                                goto out_gunlock;
1345                        }
1346                }
1347        }
1348
1349        /* Check out the dir to be renamed */
1350
1351        if (dir_rename) {
1352                error = gfs2_permission(odentry->d_inode, MAY_WRITE);
1353                if (error)
1354                        goto out_gunlock;
1355        }
1356
1357        if (nip == NULL)
1358                alloc_required = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
1359        error = alloc_required;
1360        if (error < 0)
1361                goto out_gunlock;
1362
1363        if (alloc_required) {
1364                error = gfs2_quota_lock_check(ndip);
1365                if (error)
1366                        goto out_gunlock;
1367
1368                error = gfs2_inplace_reserve(ndip, sdp->sd_max_dirres);
1369                if (error)
1370                        goto out_gunlock_q;
1371
1372                error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
1373                                         gfs2_rg_blocks(ndip, sdp->sd_max_dirres) +
1374                                         4 * RES_DINODE + 4 * RES_LEAF +
1375                                         RES_STATFS + RES_QUOTA + 4, 0);
1376                if (error)
1377                        goto out_ipreserv;
1378        } else {
1379                error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
1380                                         5 * RES_LEAF + 4, 0);
1381                if (error)
1382                        goto out_gunlock;
1383        }
1384
1385        /* Remove the target file, if it exists */
1386
1387        if (nip) {
1388                struct buffer_head *bh;
1389                error = gfs2_meta_inode_buffer(nip, &bh);
1390                if (error)
1391                        goto out_end_trans;
1392                error = gfs2_unlink_inode(ndip, ndentry, bh);
1393                brelse(bh);
1394        }
1395
1396        if (dir_rename) {
1397                error = gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
1398                if (error)
1399                        goto out_end_trans;
1400        } else {
1401                struct buffer_head *dibh;
1402                error = gfs2_meta_inode_buffer(ip, &dibh);
1403                if (error)
1404                        goto out_end_trans;
1405                ip->i_inode.i_ctime = CURRENT_TIME;
1406                gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1407                gfs2_dinode_out(ip, dibh->b_data);
1408                brelse(dibh);
1409        }
1410
1411        error = gfs2_dir_del(odip, odentry);
1412        if (error)
1413                goto out_end_trans;
1414
1415        error = gfs2_dir_add(ndir, &ndentry->d_name, ip);
1416        if (error)
1417                goto out_end_trans;
1418
1419out_end_trans:
1420        gfs2_trans_end(sdp);
1421out_ipreserv:
1422        if (alloc_required)
1423                gfs2_inplace_release(ndip);
1424out_gunlock_q:
1425        if (alloc_required)
1426                gfs2_quota_unlock(ndip);
1427out_gunlock:
1428        while (x--) {
1429                gfs2_glock_dq(ghs + x);
1430                gfs2_holder_uninit(ghs + x);
1431        }
1432out_gunlock_r:
1433        if (r_gh.gh_gl)
1434                gfs2_glock_dq_uninit(&r_gh);
1435out:
1436        return error;
1437}
1438
1439/**
1440 * gfs2_follow_link - Follow a symbolic link
1441 * @dentry: The dentry of the link
1442 * @nd: Data that we pass to vfs_follow_link()
1443 *
1444 * This can handle symlinks of any size.
1445 *
1446 * Returns: 0 on success or error code
1447 */
1448
1449static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
1450{
1451        struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
1452        struct gfs2_holder i_gh;
1453        struct buffer_head *dibh;
1454        unsigned int size;
1455        char *buf;
1456        int error;
1457
1458        gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1459        error = gfs2_glock_nq(&i_gh);
1460        if (error) {
1461                gfs2_holder_uninit(&i_gh);
1462                nd_set_link(nd, ERR_PTR(error));
1463                return NULL;
1464        }
1465
1466        size = (unsigned int)i_size_read(&ip->i_inode);
1467        if (size == 0) {
1468                gfs2_consist_inode(ip);
1469                buf = ERR_PTR(-EIO);
1470                goto out;
1471        }
1472
1473        error = gfs2_meta_inode_buffer(ip, &dibh);
1474        if (error) {
1475                buf = ERR_PTR(error);
1476                goto out;
1477        }
1478
1479        buf = kzalloc(size + 1, GFP_NOFS);
1480        if (!buf)
1481                buf = ERR_PTR(-ENOMEM);
1482        else
1483                memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
1484        brelse(dibh);
1485out:
1486        gfs2_glock_dq_uninit(&i_gh);
1487        nd_set_link(nd, buf);
1488        return NULL;
1489}
1490
1491static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1492{
1493        char *s = nd_get_link(nd);
1494        if (!IS_ERR(s))
1495                kfree(s);
1496}
1497
1498/**
1499 * gfs2_permission -
1500 * @inode: The inode
1501 * @mask: The mask to be tested
1502 * @flags: Indicates whether this is an RCU path walk or not
1503 *
1504 * This may be called from the VFS directly, or from within GFS2 with the
1505 * inode locked, so we look to see if the glock is already locked and only
1506 * lock the glock if its not already been done.
1507 *
1508 * Returns: errno
1509 */
1510
1511int gfs2_permission(struct inode *inode, int mask)
1512{
1513        struct gfs2_inode *ip;
1514        struct gfs2_holder i_gh;
1515        int error;
1516        int unlock = 0;
1517
1518
1519        ip = GFS2_I(inode);
1520        if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1521                if (mask & MAY_NOT_BLOCK)
1522                        return -ECHILD;
1523                error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
1524                if (error)
1525                        return error;
1526                unlock = 1;
1527        }
1528
1529        if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
1530                error = -EACCES;
1531        else
1532                error = generic_permission(inode, mask);
1533        if (unlock)
1534                gfs2_glock_dq_uninit(&i_gh);
1535
1536        return error;
1537}
1538
1539static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1540{
1541        setattr_copy(inode, attr);
1542        mark_inode_dirty(inode);
1543        return 0;
1544}
1545
1546/**
1547 * gfs2_setattr_simple -
1548 * @ip:
1549 * @attr:
1550 *
1551 * Returns: errno
1552 */
1553
1554int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
1555{
1556        int error;
1557
1558        if (current->journal_info)
1559                return __gfs2_setattr_simple(inode, attr);
1560
1561        error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
1562        if (error)
1563                return error;
1564
1565        error = __gfs2_setattr_simple(inode, attr);
1566        gfs2_trans_end(GFS2_SB(inode));
1567        return error;
1568}
1569
1570static int setattr_chown(struct inode *inode, struct iattr *attr)
1571{
1572        struct gfs2_inode *ip = GFS2_I(inode);
1573        struct gfs2_sbd *sdp = GFS2_SB(inode);
1574        u32 ouid, ogid, nuid, ngid;
1575        int error;
1576
1577        ouid = inode->i_uid;
1578        ogid = inode->i_gid;
1579        nuid = attr->ia_uid;
1580        ngid = attr->ia_gid;
1581
1582        if (!(attr->ia_valid & ATTR_UID) || ouid == nuid)
1583                ouid = nuid = NO_QUOTA_CHANGE;
1584        if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
1585                ogid = ngid = NO_QUOTA_CHANGE;
1586
1587        error = gfs2_quota_lock(ip, nuid, ngid);
1588        if (error)
1589                return error;
1590
1591        if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
1592                error = gfs2_quota_check(ip, nuid, ngid);
1593                if (error)
1594                        goto out_gunlock_q;
1595        }
1596
1597        error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
1598        if (error)
1599                goto out_gunlock_q;
1600
1601        error = gfs2_setattr_simple(inode, attr);
1602        if (error)
1603                goto out_end_trans;
1604
1605        if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
1606                u64 blocks = gfs2_get_inode_blocks(&ip->i_inode);
1607                gfs2_quota_change(ip, -blocks, ouid, ogid);
1608                gfs2_quota_change(ip, blocks, nuid, ngid);
1609        }
1610
1611out_end_trans:
1612        gfs2_trans_end(sdp);
1613out_gunlock_q:
1614        gfs2_quota_unlock(ip);
1615        return error;
1616}
1617
1618/**
1619 * gfs2_setattr - Change attributes on an inode
1620 * @dentry: The dentry which is changing
1621 * @attr: The structure describing the change
1622 *
1623 * The VFS layer wants to change one or more of an inodes attributes.  Write
1624 * that change out to disk.
1625 *
1626 * Returns: errno
1627 */
1628
1629static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1630{
1631        struct inode *inode = dentry->d_inode;
1632        struct gfs2_inode *ip = GFS2_I(inode);
1633        struct gfs2_holder i_gh;
1634        int error;
1635
1636        error = gfs2_rs_alloc(ip);
1637        if (error)
1638                return error;
1639
1640        error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1641        if (error)
1642                return error;
1643
1644        error = -EPERM;
1645        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1646                goto out;
1647
1648        error = inode_change_ok(inode, attr);
1649        if (error)
1650                goto out;
1651
1652        if (attr->ia_valid & ATTR_SIZE)
1653                error = gfs2_setattr_size(inode, attr->ia_size);
1654        else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1655                error = setattr_chown(inode, attr);
1656        else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1657                error = gfs2_acl_chmod(ip, attr);
1658        else
1659                error = gfs2_setattr_simple(inode, attr);
1660
1661out:
1662        if (!error)
1663                mark_inode_dirty(inode);
1664        gfs2_glock_dq_uninit(&i_gh);
1665        return error;
1666}
1667
1668/**
1669 * gfs2_getattr - Read out an inode's attributes
1670 * @mnt: The vfsmount the inode is being accessed from
1671 * @dentry: The dentry to stat
1672 * @stat: The inode's stats
1673 *
1674 * This may be called from the VFS directly, or from within GFS2 with the
1675 * inode locked, so we look to see if the glock is already locked and only
1676 * lock the glock if its not already been done. Note that its the NFS
1677 * readdirplus operation which causes this to be called (from filldir)
1678 * with the glock already held.
1679 *
1680 * Returns: errno
1681 */
1682
1683static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1684                        struct kstat *stat)
1685{
1686        struct inode *inode = dentry->d_inode;
1687        struct gfs2_inode *ip = GFS2_I(inode);
1688        struct gfs2_holder gh;
1689        int error;
1690        int unlock = 0;
1691
1692        if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1693                error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1694                if (error)
1695                        return error;
1696                unlock = 1;
1697        }
1698
1699        generic_fillattr(inode, stat);
1700        if (unlock)
1701                gfs2_glock_dq_uninit(&gh);
1702
1703        return 0;
1704}
1705
1706static int gfs2_setxattr(struct dentry *dentry, const char *name,
1707                         const void *data, size_t size, int flags)
1708{
1709        struct inode *inode = dentry->d_inode;
1710        struct gfs2_inode *ip = GFS2_I(inode);
1711        struct gfs2_holder gh;
1712        int ret;
1713
1714        gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1715        ret = gfs2_glock_nq(&gh);
1716        if (ret == 0) {
1717                ret = gfs2_rs_alloc(ip);
1718                if (ret == 0)
1719                        ret = generic_setxattr(dentry, name, data, size, flags);
1720                gfs2_glock_dq(&gh);
1721        }
1722        gfs2_holder_uninit(&gh);
1723        return ret;
1724}
1725
1726static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1727                             void *data, size_t size)
1728{
1729        struct inode *inode = dentry->d_inode;
1730        struct gfs2_inode *ip = GFS2_I(inode);
1731        struct gfs2_holder gh;
1732        int ret;
1733
1734        gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1735        ret = gfs2_glock_nq(&gh);
1736        if (ret == 0) {
1737                ret = generic_getxattr(dentry, name, data, size);
1738                gfs2_glock_dq(&gh);
1739        }
1740        gfs2_holder_uninit(&gh);
1741        return ret;
1742}
1743
1744static int gfs2_removexattr(struct dentry *dentry, const char *name)
1745{
1746        struct inode *inode = dentry->d_inode;
1747        struct gfs2_inode *ip = GFS2_I(inode);
1748        struct gfs2_holder gh;
1749        int ret;
1750
1751        gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
1752        ret = gfs2_glock_nq(&gh);
1753        if (ret == 0) {
1754                ret = gfs2_rs_alloc(ip);
1755                if (ret == 0)
1756                        ret = generic_removexattr(dentry, name);
1757                gfs2_glock_dq(&gh);
1758        }
1759        gfs2_holder_uninit(&gh);
1760        return ret;
1761}
1762
1763static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1764                       u64 start, u64 len)
1765{
1766        struct gfs2_inode *ip = GFS2_I(inode);
1767        struct gfs2_holder gh;
1768        int ret;
1769
1770        ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1771        if (ret)
1772                return ret;
1773
1774        mutex_lock(&inode->i_mutex);
1775
1776        ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
1777        if (ret)
1778                goto out;
1779
1780        if (gfs2_is_stuffed(ip)) {
1781                u64 phys = ip->i_no_addr << inode->i_blkbits;
1782                u64 size = i_size_read(inode);
1783                u32 flags = FIEMAP_EXTENT_LAST|FIEMAP_EXTENT_NOT_ALIGNED|
1784                            FIEMAP_EXTENT_DATA_INLINE;
1785                phys += sizeof(struct gfs2_dinode);
1786                phys += start;
1787                if (start + len > size)
1788                        len = size - start;
1789                if (start < size)
1790                        ret = fiemap_fill_next_extent(fieinfo, start, phys,
1791                                                      len, flags);
1792                if (ret == 1)
1793                        ret = 0;
1794        } else {
1795                ret = __generic_block_fiemap(inode, fieinfo, start, len,
1796                                             gfs2_block_map);
1797        }
1798
1799        gfs2_glock_dq_uninit(&gh);
1800out:
1801        mutex_unlock(&inode->i_mutex);
1802        return ret;
1803}
1804
1805const struct inode_operations gfs2_file_iops = {
1806        .permission = gfs2_permission,
1807        .setattr = gfs2_setattr,
1808        .getattr = gfs2_getattr,
1809        .setxattr = gfs2_setxattr,
1810        .getxattr = gfs2_getxattr,
1811        .listxattr = gfs2_listxattr,
1812        .removexattr = gfs2_removexattr,
1813        .fiemap = gfs2_fiemap,
1814        .get_acl = gfs2_get_acl,
1815};
1816
1817const struct inode_operations gfs2_dir_iops = {
1818        .create = gfs2_create,
1819        .lookup = gfs2_lookup,
1820        .link = gfs2_link,
1821        .unlink = gfs2_unlink,
1822        .symlink = gfs2_symlink,
1823        .mkdir = gfs2_mkdir,
1824        .rmdir = gfs2_unlink,
1825        .mknod = gfs2_mknod,
1826        .rename = gfs2_rename,
1827        .permission = gfs2_permission,
1828        .setattr = gfs2_setattr,
1829        .getattr = gfs2_getattr,
1830        .setxattr = gfs2_setxattr,
1831        .getxattr = gfs2_getxattr,
1832        .listxattr = gfs2_listxattr,
1833        .removexattr = gfs2_removexattr,
1834        .fiemap = gfs2_fiemap,
1835        .get_acl = gfs2_get_acl,
1836};
1837
1838const struct inode_operations gfs2_symlink_iops = {
1839        .readlink = generic_readlink,
1840        .follow_link = gfs2_follow_link,
1841        .put_link = gfs2_put_link,
1842        .permission = gfs2_permission,
1843        .setattr = gfs2_setattr,
1844        .getattr = gfs2_getattr,
1845        .setxattr = gfs2_setxattr,
1846        .getxattr = gfs2_getxattr,
1847        .listxattr = gfs2_listxattr,
1848        .removexattr = gfs2_removexattr,
1849        .fiemap = gfs2_fiemap,
1850        .get_acl = gfs2_get_acl,
1851};
1852
1853
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