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1/*2 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.3 *4 * This software may be freely redistributed under the terms of the5 * GNU General Public License.6 *7 * You should have received a copy of the GNU General Public License8 * along with this program; if not, write to the Free Software9 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.10 *11 * Authors: David Woodhouse <dwmw2@infradead.org>12 * David Howells <dhowells@redhat.com>13 *14 */15 16#include <linux/kernel.h>17#include <linux/module.h>18#include <linux/init.h>19#include <linux/fs.h>20#include <linux/pagemap.h>21#include <linux/sched.h>22#include <linux/mount.h>23#include <linux/namei.h>24#include <linux/iversion.h>25#include "internal.h"26#include "afs_fs.h"27 28static const struct inode_operations afs_symlink_inode_operations = {29 .get_link = page_get_link,30};31 32static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)33{34 static unsigned long once_only;35 36 pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);37 pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",38 vnode->status.abort_code,39 vnode->status.mode,40 vnode->status.size,41 vnode->status.data_version);42 pr_warn("kAFS: vnode %llx:%llx:%x\n",43 vnode->fid.vid,44 vnode->fid.vnode,45 vnode->fid.unique);46 if (parent_vnode)47 pr_warn("kAFS: dir %llx:%llx:%x\n",48 parent_vnode->fid.vid,49 parent_vnode->fid.vnode,50 parent_vnode->fid.unique);51 52 if (!test_and_set_bit(0, &once_only))53 dump_stack();54}55 56/*57 * Set parameters for the netfs library58 */59static void afs_set_netfs_context(struct afs_vnode *vnode)60{61 netfs_inode_init(&vnode->netfs, &afs_req_ops, true);62}63 64/*65 * Initialise an inode from the vnode status.66 */67static int afs_inode_init_from_status(struct afs_operation *op,68 struct afs_vnode_param *vp,69 struct afs_vnode *vnode)70{71 struct afs_file_status *status = &vp->scb.status;72 struct inode *inode = AFS_VNODE_TO_I(vnode);73 struct timespec64 t;74 75 _enter("{%llx:%llu.%u} %s",76 vp->fid.vid, vp->fid.vnode, vp->fid.unique,77 op->type ? op->type->name : "???");78 79 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",80 status->type,81 status->nlink,82 (unsigned long long) status->size,83 status->data_version,84 status->mode);85 86 write_seqlock(&vnode->cb_lock);87 88 vnode->cb_v_check = op->cb_v_break;89 vnode->status = *status;90 91 t = status->mtime_client;92 inode_set_ctime_to_ts(inode, t);93 inode_set_mtime_to_ts(inode, t);94 inode_set_atime_to_ts(inode, t);95 inode->i_flags |= S_NOATIME;96 inode->i_uid = make_kuid(&init_user_ns, status->owner);97 inode->i_gid = make_kgid(&init_user_ns, status->group);98 set_nlink(&vnode->netfs.inode, status->nlink);99 100 switch (status->type) {101 case AFS_FTYPE_FILE:102 inode->i_mode = S_IFREG | (status->mode & S_IALLUGO);103 inode->i_op = &afs_file_inode_operations;104 inode->i_fop = &afs_file_operations;105 inode->i_mapping->a_ops = &afs_file_aops;106 mapping_set_large_folios(inode->i_mapping);107 break;108 case AFS_FTYPE_DIR:109 inode->i_mode = S_IFDIR | (status->mode & S_IALLUGO);110 inode->i_op = &afs_dir_inode_operations;111 inode->i_fop = &afs_dir_file_operations;112 inode->i_mapping->a_ops = &afs_dir_aops;113 mapping_set_large_folios(inode->i_mapping);114 break;115 case AFS_FTYPE_SYMLINK:116 /* Symlinks with a mode of 0644 are actually mountpoints. */117 if ((status->mode & 0777) == 0644) {118 inode->i_flags |= S_AUTOMOUNT;119 120 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);121 122 inode->i_mode = S_IFDIR | 0555;123 inode->i_op = &afs_mntpt_inode_operations;124 inode->i_fop = &afs_mntpt_file_operations;125 inode->i_mapping->a_ops = &afs_symlink_aops;126 } else {127 inode->i_mode = S_IFLNK | status->mode;128 inode->i_op = &afs_symlink_inode_operations;129 inode->i_mapping->a_ops = &afs_symlink_aops;130 }131 inode_nohighmem(inode);132 break;133 default:134 dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);135 write_sequnlock(&vnode->cb_lock);136 return afs_protocol_error(NULL, afs_eproto_file_type);137 }138 139 afs_set_i_size(vnode, status->size);140 afs_set_netfs_context(vnode);141 142 vnode->invalid_before = status->data_version;143 inode_set_iversion_raw(&vnode->netfs.inode, status->data_version);144 145 if (!vp->scb.have_cb) {146 /* it's a symlink we just created (the fileserver147 * didn't give us a callback) */148 atomic64_set(&vnode->cb_expires_at, AFS_NO_CB_PROMISE);149 } else {150 vnode->cb_server = op->server;151 atomic64_set(&vnode->cb_expires_at, vp->scb.callback.expires_at);152 }153 154 write_sequnlock(&vnode->cb_lock);155 return 0;156}157 158/*159 * Update the core inode struct from a returned status record.160 */161static void afs_apply_status(struct afs_operation *op,162 struct afs_vnode_param *vp)163{164 struct afs_file_status *status = &vp->scb.status;165 struct afs_vnode *vnode = vp->vnode;166 struct inode *inode = &vnode->netfs.inode;167 struct timespec64 t;168 umode_t mode;169 bool unexpected_jump = false;170 bool data_changed = false;171 bool change_size = vp->set_size;172 173 _enter("{%llx:%llu.%u} %s",174 vp->fid.vid, vp->fid.vnode, vp->fid.unique,175 op->type ? op->type->name : "???");176 177 BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));178 179 if (status->type != vnode->status.type) {180 pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",181 vnode->fid.vid,182 vnode->fid.vnode,183 vnode->fid.unique,184 status->type, vnode->status.type);185 afs_protocol_error(NULL, afs_eproto_bad_status);186 return;187 }188 189 if (status->nlink != vnode->status.nlink)190 set_nlink(inode, status->nlink);191 192 if (status->owner != vnode->status.owner)193 inode->i_uid = make_kuid(&init_user_ns, status->owner);194 195 if (status->group != vnode->status.group)196 inode->i_gid = make_kgid(&init_user_ns, status->group);197 198 if (status->mode != vnode->status.mode) {199 mode = inode->i_mode;200 mode &= ~S_IALLUGO;201 mode |= status->mode & S_IALLUGO;202 WRITE_ONCE(inode->i_mode, mode);203 }204 205 t = status->mtime_client;206 inode_set_mtime_to_ts(inode, t);207 if (vp->update_ctime)208 inode_set_ctime_to_ts(inode, op->ctime);209 210 if (vnode->status.data_version != status->data_version)211 data_changed = true;212 213 vnode->status = *status;214 215 if (vp->dv_before + vp->dv_delta != status->data_version) {216 if (vnode->cb_ro_snapshot == atomic_read(&vnode->volume->cb_ro_snapshot) &&217 atomic64_read(&vnode->cb_expires_at) != AFS_NO_CB_PROMISE)218 pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s (op=%x)\n",219 vnode->fid.vid, vnode->fid.vnode,220 (unsigned long long)vp->dv_before + vp->dv_delta,221 (unsigned long long)status->data_version,222 op->type ? op->type->name : "???",223 op->debug_id);224 225 vnode->invalid_before = status->data_version;226 if (vnode->status.type == AFS_FTYPE_DIR) {227 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))228 afs_stat_v(vnode, n_inval);229 } else {230 set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);231 }232 change_size = true;233 data_changed = true;234 unexpected_jump = true;235 } else if (vnode->status.type == AFS_FTYPE_DIR) {236 /* Expected directory change is handled elsewhere so237 * that we can locally edit the directory and save on a238 * download.239 */240 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))241 data_changed = false;242 change_size = true;243 }244 245 if (data_changed) {246 inode_set_iversion_raw(inode, status->data_version);247 248 /* Only update the size if the data version jumped. If the249 * file is being modified locally, then we might have our own250 * idea of what the size should be that's not the same as251 * what's on the server.252 */253 vnode->netfs.remote_i_size = status->size;254 if (change_size || status->size > i_size_read(inode)) {255 afs_set_i_size(vnode, status->size);256 if (unexpected_jump)257 vnode->netfs.zero_point = status->size;258 inode_set_ctime_to_ts(inode, t);259 inode_set_atime_to_ts(inode, t);260 }261 }262}263 264/*265 * Apply a callback to a vnode.266 */267static void afs_apply_callback(struct afs_operation *op,268 struct afs_vnode_param *vp)269{270 struct afs_callback *cb = &vp->scb.callback;271 struct afs_vnode *vnode = vp->vnode;272 273 if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {274 if (op->volume->type == AFSVL_RWVOL)275 vnode->cb_server = op->server;276 atomic64_set(&vnode->cb_expires_at, cb->expires_at);277 }278}279 280/*281 * Apply the received status and callback to an inode all in the same critical282 * section to avoid races with afs_validate().283 */284void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)285{286 struct afs_vnode *vnode = vp->vnode;287 288 _enter("");289 290 write_seqlock(&vnode->cb_lock);291 292 if (vp->scb.have_error) {293 /* A YFS server will return this from RemoveFile2 and AFS and294 * YFS will return this from InlineBulkStatus.295 */296 if (vp->scb.status.abort_code == VNOVNODE) {297 set_bit(AFS_VNODE_DELETED, &vnode->flags);298 clear_nlink(&vnode->netfs.inode);299 __afs_break_callback(vnode, afs_cb_break_for_deleted);300 op->flags &= ~AFS_OPERATION_DIR_CONFLICT;301 }302 } else if (vp->scb.have_status) {303 if (vp->speculative &&304 (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||305 vp->dv_before != vnode->status.data_version))306 /* Ignore the result of a speculative bulk status fetch307 * if it splits around a modification op, thereby308 * appearing to regress the data version.309 */310 goto out;311 afs_apply_status(op, vp);312 if (vp->scb.have_cb)313 afs_apply_callback(op, vp);314 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {315 drop_nlink(&vnode->netfs.inode);316 if (vnode->netfs.inode.i_nlink == 0) {317 set_bit(AFS_VNODE_DELETED, &vnode->flags);318 __afs_break_callback(vnode, afs_cb_break_for_deleted);319 }320 }321 322out:323 write_sequnlock(&vnode->cb_lock);324 325 if (vp->scb.have_status)326 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);327}328 329static void afs_fetch_status_success(struct afs_operation *op)330{331 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];332 struct afs_vnode *vnode = vp->vnode;333 int ret;334 335 if (vnode->netfs.inode.i_state & I_NEW) {336 ret = afs_inode_init_from_status(op, vp, vnode);337 afs_op_set_error(op, ret);338 if (ret == 0)339 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);340 } else {341 afs_vnode_commit_status(op, vp);342 }343}344 345const struct afs_operation_ops afs_fetch_status_operation = {346 .issue_afs_rpc = afs_fs_fetch_status,347 .issue_yfs_rpc = yfs_fs_fetch_status,348 .success = afs_fetch_status_success,349 .aborted = afs_check_for_remote_deletion,350};351 352/*353 * Fetch file status from the volume.354 */355int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,356 afs_access_t *_caller_access)357{358 struct afs_operation *op;359 360 _enter("%s,{%llx:%llu.%u,S=%lx}",361 vnode->volume->name,362 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,363 vnode->flags);364 365 op = afs_alloc_operation(key, vnode->volume);366 if (IS_ERR(op))367 return PTR_ERR(op);368 369 afs_op_set_vnode(op, 0, vnode);370 371 op->nr_files = 1;372 op->ops = &afs_fetch_status_operation;373 afs_begin_vnode_operation(op);374 afs_wait_for_operation(op);375 376 if (_caller_access)377 *_caller_access = op->file[0].scb.status.caller_access;378 return afs_put_operation(op);379}380 381/*382 * ilookup() comparator383 */384int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)385{386 struct afs_vnode *vnode = AFS_FS_I(inode);387 struct afs_fid *fid = opaque;388 389 return (fid->vnode == vnode->fid.vnode &&390 fid->vnode_hi == vnode->fid.vnode_hi &&391 fid->unique == vnode->fid.unique);392}393 394/*395 * iget5() comparator396 */397static int afs_iget5_test(struct inode *inode, void *opaque)398{399 struct afs_vnode_param *vp = opaque;400 //struct afs_vnode *vnode = AFS_FS_I(inode);401 402 return afs_ilookup5_test_by_fid(inode, &vp->fid);403}404 405/*406 * iget5() inode initialiser407 */408static int afs_iget5_set(struct inode *inode, void *opaque)409{410 struct afs_vnode_param *vp = opaque;411 struct afs_super_info *as = AFS_FS_S(inode->i_sb);412 struct afs_vnode *vnode = AFS_FS_I(inode);413 414 vnode->volume = as->volume;415 vnode->fid = vp->fid;416 417 /* YFS supports 96-bit vnode IDs, but Linux only supports418 * 64-bit inode numbers.419 */420 inode->i_ino = vnode->fid.vnode;421 inode->i_generation = vnode->fid.unique;422 return 0;423}424 425/*426 * Get a cache cookie for an inode.427 */428static void afs_get_inode_cache(struct afs_vnode *vnode)429{430#ifdef CONFIG_AFS_FSCACHE431 struct {432 __be32 vnode_id;433 __be32 unique;434 __be32 vnode_id_ext[2]; /* Allow for a 96-bit key */435 } __packed key;436 struct afs_vnode_cache_aux aux;437 438 if (vnode->status.type != AFS_FTYPE_FILE) {439 vnode->netfs.cache = NULL;440 return;441 }442 443 key.vnode_id = htonl(vnode->fid.vnode);444 key.unique = htonl(vnode->fid.unique);445 key.vnode_id_ext[0] = htonl(vnode->fid.vnode >> 32);446 key.vnode_id_ext[1] = htonl(vnode->fid.vnode_hi);447 afs_set_cache_aux(vnode, &aux);448 449 afs_vnode_set_cache(vnode,450 fscache_acquire_cookie(451 vnode->volume->cache,452 vnode->status.type == AFS_FTYPE_FILE ?453 0 : FSCACHE_ADV_SINGLE_CHUNK,454 &key, sizeof(key),455 &aux, sizeof(aux),456 i_size_read(&vnode->netfs.inode)));457#endif458}459 460/*461 * inode retrieval462 */463struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)464{465 struct afs_vnode_param *dvp = &op->file[0];466 struct super_block *sb = dvp->vnode->netfs.inode.i_sb;467 struct afs_vnode *vnode;468 struct inode *inode;469 int ret;470 471 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);472 473 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);474 if (!inode) {475 _leave(" = -ENOMEM");476 return ERR_PTR(-ENOMEM);477 }478 479 vnode = AFS_FS_I(inode);480 481 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",482 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);483 484 /* deal with an existing inode */485 if (!(inode->i_state & I_NEW)) {486 _leave(" = %p", inode);487 return inode;488 }489 490 ret = afs_inode_init_from_status(op, vp, vnode);491 if (ret < 0)492 goto bad_inode;493 494 afs_get_inode_cache(vnode);495 496 /* success */497 clear_bit(AFS_VNODE_UNSET, &vnode->flags);498 unlock_new_inode(inode);499 _leave(" = %p", inode);500 return inode;501 502 /* failure */503bad_inode:504 iget_failed(inode);505 _leave(" = %d [bad]", ret);506 return ERR_PTR(ret);507}508 509static int afs_iget5_set_root(struct inode *inode, void *opaque)510{511 struct afs_super_info *as = AFS_FS_S(inode->i_sb);512 struct afs_vnode *vnode = AFS_FS_I(inode);513 514 vnode->volume = as->volume;515 vnode->fid.vid = as->volume->vid;516 vnode->fid.vnode = 1;517 vnode->fid.unique = 1;518 inode->i_ino = 1;519 inode->i_generation = 1;520 return 0;521}522 523/*524 * Set up the root inode for a volume. This is always vnode 1, unique 1 within525 * the volume.526 */527struct inode *afs_root_iget(struct super_block *sb, struct key *key)528{529 struct afs_super_info *as = AFS_FS_S(sb);530 struct afs_operation *op;531 struct afs_vnode *vnode;532 struct inode *inode;533 int ret;534 535 _enter(",{%llx},,", as->volume->vid);536 537 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);538 if (!inode) {539 _leave(" = -ENOMEM");540 return ERR_PTR(-ENOMEM);541 }542 543 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);544 545 BUG_ON(!(inode->i_state & I_NEW));546 547 vnode = AFS_FS_I(inode);548 vnode->cb_v_check = atomic_read(&as->volume->cb_v_break);549 afs_set_netfs_context(vnode);550 551 op = afs_alloc_operation(key, as->volume);552 if (IS_ERR(op)) {553 ret = PTR_ERR(op);554 goto error;555 }556 557 afs_op_set_vnode(op, 0, vnode);558 559 op->nr_files = 1;560 op->ops = &afs_fetch_status_operation;561 ret = afs_do_sync_operation(op);562 if (ret < 0)563 goto error;564 565 afs_get_inode_cache(vnode);566 567 clear_bit(AFS_VNODE_UNSET, &vnode->flags);568 unlock_new_inode(inode);569 _leave(" = %p", inode);570 return inode;571 572error:573 iget_failed(inode);574 _leave(" = %d [bad]", ret);575 return ERR_PTR(ret);576}577 578/*579 * read the attributes of an inode580 */581int afs_getattr(struct mnt_idmap *idmap, const struct path *path,582 struct kstat *stat, u32 request_mask, unsigned int query_flags)583{584 struct inode *inode = d_inode(path->dentry);585 struct afs_vnode *vnode = AFS_FS_I(inode);586 struct key *key;587 int ret, seq;588 589 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);590 591 if (vnode->volume &&592 !(query_flags & AT_STATX_DONT_SYNC) &&593 atomic64_read(&vnode->cb_expires_at) == AFS_NO_CB_PROMISE) {594 key = afs_request_key(vnode->volume->cell);595 if (IS_ERR(key))596 return PTR_ERR(key);597 ret = afs_validate(vnode, key);598 key_put(key);599 if (ret < 0)600 return ret;601 }602 603 do {604 seq = read_seqbegin(&vnode->cb_lock);605 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);606 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&607 stat->nlink > 0)608 stat->nlink -= 1;609 610 /* Lie about the size of directories. We maintain a locally611 * edited copy and may make different allocation decisions on612 * it, but we need to give userspace the server's size.613 */614 if (S_ISDIR(inode->i_mode))615 stat->size = vnode->netfs.remote_i_size;616 } while (read_seqretry(&vnode->cb_lock, seq));617 618 return 0;619}620 621/*622 * discard an AFS inode623 */624int afs_drop_inode(struct inode *inode)625{626 _enter("");627 628 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))629 return generic_delete_inode(inode);630 else631 return generic_drop_inode(inode);632}633 634/*635 * clear an AFS inode636 */637void afs_evict_inode(struct inode *inode)638{639 struct afs_vnode_cache_aux aux;640 struct afs_vnode *vnode = AFS_FS_I(inode);641 642 _enter("{%llx:%llu.%d}",643 vnode->fid.vid,644 vnode->fid.vnode,645 vnode->fid.unique);646 647 _debug("CLEAR INODE %p", inode);648 649 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);650 651 netfs_wait_for_outstanding_io(inode);652 truncate_inode_pages_final(&inode->i_data);653 654 afs_set_cache_aux(vnode, &aux);655 netfs_clear_inode_writeback(inode, &aux);656 clear_inode(inode);657 658 while (!list_empty(&vnode->wb_keys)) {659 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,660 struct afs_wb_key, vnode_link);661 list_del(&wbk->vnode_link);662 afs_put_wb_key(wbk);663 }664 665 fscache_relinquish_cookie(afs_vnode_cache(vnode),666 test_bit(AFS_VNODE_DELETED, &vnode->flags));667 668 afs_prune_wb_keys(vnode);669 afs_put_permits(rcu_access_pointer(vnode->permit_cache));670 key_put(vnode->silly_key);671 vnode->silly_key = NULL;672 key_put(vnode->lock_key);673 vnode->lock_key = NULL;674 _leave("");675}676 677static void afs_setattr_success(struct afs_operation *op)678{679 struct afs_vnode_param *vp = &op->file[0];680 struct inode *inode = &vp->vnode->netfs.inode;681 loff_t old_i_size = i_size_read(inode);682 683 op->setattr.old_i_size = old_i_size;684 afs_vnode_commit_status(op, vp);685 /* inode->i_size has now been changed. */686 687 if (op->setattr.attr->ia_valid & ATTR_SIZE) {688 loff_t size = op->setattr.attr->ia_size;689 if (size > old_i_size)690 pagecache_isize_extended(inode, old_i_size, size);691 }692}693 694static void afs_setattr_edit_file(struct afs_operation *op)695{696 struct afs_vnode_param *vp = &op->file[0];697 struct afs_vnode *vnode = vp->vnode;698 struct inode *inode = &vnode->netfs.inode;699 700 if (op->setattr.attr->ia_valid & ATTR_SIZE) {701 loff_t size = op->setattr.attr->ia_size;702 loff_t old = op->setattr.old_i_size;703 704 /* Note: inode->i_size was updated by afs_apply_status() inside705 * the I/O and callback locks.706 */707 708 if (size != old) {709 truncate_pagecache(inode, size);710 netfs_resize_file(&vnode->netfs, size, true);711 fscache_resize_cookie(afs_vnode_cache(vnode), size);712 }713 }714}715 716static const struct afs_operation_ops afs_setattr_operation = {717 .issue_afs_rpc = afs_fs_setattr,718 .issue_yfs_rpc = yfs_fs_setattr,719 .success = afs_setattr_success,720 .edit_dir = afs_setattr_edit_file,721};722 723/*724 * set the attributes of an inode725 */726int afs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,727 struct iattr *attr)728{729 const unsigned int supported =730 ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |731 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET | ATTR_TOUCH;732 struct afs_operation *op;733 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));734 struct inode *inode = &vnode->netfs.inode;735 loff_t i_size;736 int ret;737 738 _enter("{%llx:%llu},{n=%pd},%x",739 vnode->fid.vid, vnode->fid.vnode, dentry,740 attr->ia_valid);741 742 if (!(attr->ia_valid & supported)) {743 _leave(" = 0 [unsupported]");744 return 0;745 }746 747 i_size = i_size_read(inode);748 if (attr->ia_valid & ATTR_SIZE) {749 if (!S_ISREG(inode->i_mode))750 return -EISDIR;751 752 ret = inode_newsize_ok(inode, attr->ia_size);753 if (ret)754 return ret;755 756 if (attr->ia_size == i_size)757 attr->ia_valid &= ~ATTR_SIZE;758 }759 760 fscache_use_cookie(afs_vnode_cache(vnode), true);761 762 /* Prevent any new writebacks from starting whilst we do this. */763 down_write(&vnode->validate_lock);764 765 if ((attr->ia_valid & ATTR_SIZE) && S_ISREG(inode->i_mode)) {766 loff_t size = attr->ia_size;767 768 /* Wait for any outstanding writes to the server to complete */769 loff_t from = min(size, i_size);770 loff_t to = max(size, i_size);771 ret = filemap_fdatawait_range(inode->i_mapping, from, to);772 if (ret < 0)773 goto out_unlock;774 775 /* Don't talk to the server if we're just shortening in-memory776 * writes that haven't gone to the server yet.777 */778 if (!(attr->ia_valid & (supported & ~ATTR_SIZE & ~ATTR_MTIME)) &&779 attr->ia_size < i_size &&780 attr->ia_size > vnode->netfs.remote_i_size) {781 truncate_setsize(inode, attr->ia_size);782 netfs_resize_file(&vnode->netfs, size, false);783 fscache_resize_cookie(afs_vnode_cache(vnode),784 attr->ia_size);785 ret = 0;786 goto out_unlock;787 }788 }789 790 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?791 afs_file_key(attr->ia_file) : NULL),792 vnode->volume);793 if (IS_ERR(op)) {794 ret = PTR_ERR(op);795 goto out_unlock;796 }797 798 afs_op_set_vnode(op, 0, vnode);799 op->setattr.attr = attr;800 801 if (attr->ia_valid & ATTR_SIZE) {802 op->file[0].dv_delta = 1;803 op->file[0].set_size = true;804 }805 op->ctime = attr->ia_ctime;806 op->file[0].update_ctime = 1;807 op->file[0].modification = true;808 809 op->ops = &afs_setattr_operation;810 ret = afs_do_sync_operation(op);811 812out_unlock:813 up_write(&vnode->validate_lock);814 fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);815 _leave(" = %d", ret);816 return ret;817}818