1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/nfs/file.c 4 * 5 * Copyright (C) 1992 Rick Sladkey 6 */ 7 #include <linux/fs.h> 8 #include <linux/file.h> 9 #include <linux/falloc.h> 10 #include <linux/mount.h> 11 #include <linux/nfs_fs.h> 12 #include <linux/nfs_ssc.h> 13 #include "delegation.h" 14 #include "internal.h" 15 #include "iostat.h" 16 #include "fscache.h" 17 #include "pnfs.h" 18 19 #include "nfstrace.h" 20 21 #ifdef CONFIG_NFS_V4_2 22 #include "nfs42.h" 23 #endif 24 25 #define NFSDBG_FACILITY NFSDBG_FILE 26 27 static int 28 nfs4_file_open(struct inode *inode, struct file *filp) 29 { 30 struct nfs_open_context *ctx; 31 struct dentry *dentry = file_dentry(filp); 32 struct dentry *parent = NULL; 33 struct inode *dir; 34 unsigned openflags = filp->f_flags; 35 struct iattr attr; 36 int err; 37 38 /* 39 * If no cached dentry exists or if it's negative, NFSv4 handled the 40 * opens in ->lookup() or ->create(). 41 * 42 * We only get this far for a cached positive dentry. We skipped 43 * revalidation, so handle it here by dropping the dentry and returning 44 * -EOPENSTALE. The VFS will retry the lookup/create/open. 45 */ 46 47 dprintk("NFS: open file(%pd2)\n", dentry); 48 49 err = nfs_check_flags(openflags); 50 if (err) 51 return err; 52 53 if ((openflags & O_ACCMODE) == 3) 54 return nfs_open(inode, filp); 55 56 /* We can't create new files here */ 57 openflags &= ~(O_CREAT|O_EXCL); 58 59 parent = dget_parent(dentry); 60 dir = d_inode(parent); 61 62 ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode, filp); 63 err = PTR_ERR(ctx); 64 if (IS_ERR(ctx)) 65 goto out; 66 67 attr.ia_valid = ATTR_OPEN; 68 if (openflags & O_TRUNC) { 69 attr.ia_valid |= ATTR_SIZE; 70 attr.ia_size = 0; 71 filemap_write_and_wait(inode->i_mapping); 72 } 73 74 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL); 75 if (IS_ERR(inode)) { 76 err = PTR_ERR(inode); 77 switch (err) { 78 default: 79 goto out_put_ctx; 80 case -ENOENT: 81 case -ESTALE: 82 case -EISDIR: 83 case -ENOTDIR: 84 case -ELOOP: 85 goto out_drop; 86 } 87 } 88 if (inode != d_inode(dentry)) 89 goto out_drop; 90 91 nfs_file_set_open_context(filp, ctx); 92 nfs_fscache_open_file(inode, filp); 93 err = 0; 94 95 out_put_ctx: 96 put_nfs_open_context(ctx); 97 out: 98 dput(parent); 99 return err; 100 101 out_drop: 102 d_drop(dentry); 103 err = -EOPENSTALE; 104 goto out_put_ctx; 105 } 106 107 /* 108 * Flush all dirty pages, and check for write errors. 109 */ 110 static int 111 nfs4_file_flush(struct file *file, fl_owner_t id) 112 { 113 struct inode *inode = file_inode(file); 114 errseq_t since; 115 116 dprintk("NFS: flush(%pD2)\n", file); 117 118 nfs_inc_stats(inode, NFSIOS_VFSFLUSH); 119 if ((file->f_mode & FMODE_WRITE) == 0) 120 return 0; 121 122 /* 123 * If we're holding a write delegation, then check if we're required 124 * to flush the i/o on close. If not, then just start the i/o now. 125 */ 126 if (!nfs4_delegation_flush_on_close(inode)) 127 return filemap_fdatawrite(file->f_mapping); 128 129 /* Flush writes to the server and return any errors */ 130 since = filemap_sample_wb_err(file->f_mapping); 131 nfs_wb_all(inode); 132 return filemap_check_wb_err(file->f_mapping, since); 133 } 134 135 #ifdef CONFIG_NFS_V4_2 136 static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, 137 struct file *file_out, loff_t pos_out, 138 size_t count, unsigned int flags) 139 { 140 struct nfs42_copy_notify_res *cn_resp = NULL; 141 struct nl4_server *nss = NULL; 142 nfs4_stateid *cnrs = NULL; 143 ssize_t ret; 144 bool sync = false; 145 146 /* Only offload copy if superblock is the same */ 147 if (file_in->f_op != &nfs4_file_operations) 148 return -EXDEV; 149 if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) || 150 !nfs_server_capable(file_inode(file_in), NFS_CAP_COPY)) 151 return -EOPNOTSUPP; 152 if (file_inode(file_in) == file_inode(file_out)) 153 return -EOPNOTSUPP; 154 /* if the copy size if smaller than 2 RPC payloads, make it 155 * synchronous 156 */ 157 if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize) 158 sync = true; 159 retry: 160 if (!nfs42_files_from_same_server(file_in, file_out)) { 161 /* 162 * for inter copy, if copy size is too small 163 * then fallback to generic copy. 164 */ 165 if (sync) 166 return -EOPNOTSUPP; 167 cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res), 168 GFP_NOFS); 169 if (unlikely(cn_resp == NULL)) 170 return -ENOMEM; 171 172 ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp); 173 if (ret) { 174 ret = -EOPNOTSUPP; 175 goto out; 176 } 177 nss = &cn_resp->cnr_src; 178 cnrs = &cn_resp->cnr_stateid; 179 } 180 ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count, 181 nss, cnrs, sync); 182 out: 183 if (!nfs42_files_from_same_server(file_in, file_out)) 184 kfree(cn_resp); 185 if (ret == -EAGAIN) 186 goto retry; 187 return ret; 188 } 189 190 static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, 191 struct file *file_out, loff_t pos_out, 192 size_t count, unsigned int flags) 193 { 194 ssize_t ret; 195 196 ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, 197 flags); 198 if (ret == -EOPNOTSUPP || ret == -EXDEV) 199 ret = generic_copy_file_range(file_in, pos_in, file_out, 200 pos_out, count, flags); 201 return ret; 202 } 203 204 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 205 { 206 loff_t ret; 207 208 switch (whence) { 209 case SEEK_HOLE: 210 case SEEK_DATA: 211 ret = nfs42_proc_llseek(filep, offset, whence); 212 if (ret != -EOPNOTSUPP) 213 return ret; 214 fallthrough; 215 default: 216 return nfs_file_llseek(filep, offset, whence); 217 } 218 } 219 220 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 221 { 222 struct inode *inode = file_inode(filep); 223 long ret; 224 225 if (!S_ISREG(inode->i_mode)) 226 return -EOPNOTSUPP; 227 228 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 229 return -EOPNOTSUPP; 230 231 ret = inode_newsize_ok(inode, offset + len); 232 if (ret < 0) 233 return ret; 234 235 if (mode & FALLOC_FL_PUNCH_HOLE) 236 return nfs42_proc_deallocate(filep, offset, len); 237 return nfs42_proc_allocate(filep, offset, len); 238 } 239 240 static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, 241 struct file *dst_file, loff_t dst_off, loff_t count, 242 unsigned int remap_flags) 243 { 244 struct inode *dst_inode = file_inode(dst_file); 245 struct nfs_server *server = NFS_SERVER(dst_inode); 246 struct inode *src_inode = file_inode(src_file); 247 unsigned int bs = server->clone_blksize; 248 bool same_inode = false; 249 int ret; 250 251 /* NFS does not support deduplication. */ 252 if (remap_flags & REMAP_FILE_DEDUP) 253 return -EOPNOTSUPP; 254 255 if (remap_flags & ~REMAP_FILE_ADVISORY) 256 return -EINVAL; 257 258 if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode)) 259 return -ETXTBSY; 260 261 /* check alignment w.r.t. clone_blksize */ 262 ret = -EINVAL; 263 if (bs) { 264 if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs)) 265 goto out; 266 if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count)) 267 goto out; 268 } 269 270 if (src_inode == dst_inode) 271 same_inode = true; 272 273 /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */ 274 if (same_inode) { 275 inode_lock(src_inode); 276 } else if (dst_inode < src_inode) { 277 inode_lock_nested(dst_inode, I_MUTEX_PARENT); 278 inode_lock_nested(src_inode, I_MUTEX_CHILD); 279 } else { 280 inode_lock_nested(src_inode, I_MUTEX_PARENT); 281 inode_lock_nested(dst_inode, I_MUTEX_CHILD); 282 } 283 284 /* flush all pending writes on both src and dst so that server 285 * has the latest data */ 286 ret = nfs_sync_inode(src_inode); 287 if (ret) 288 goto out_unlock; 289 ret = nfs_sync_inode(dst_inode); 290 if (ret) 291 goto out_unlock; 292 293 ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count); 294 295 /* truncate inode page cache of the dst range so that future reads can fetch 296 * new data from server */ 297 if (!ret) 298 truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1); 299 300 out_unlock: 301 if (same_inode) { 302 inode_unlock(src_inode); 303 } else if (dst_inode < src_inode) { 304 inode_unlock(src_inode); 305 inode_unlock(dst_inode); 306 } else { 307 inode_unlock(dst_inode); 308 inode_unlock(src_inode); 309 } 310 out: 311 return ret < 0 ? ret : count; 312 } 313 314 static int read_name_gen = 1; 315 #define SSC_READ_NAME_BODY "ssc_read_%d" 316 317 static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, 318 struct nfs_fh *src_fh, nfs4_stateid *stateid) 319 { 320 struct nfs_fattr *fattr = nfs_alloc_fattr(); 321 struct file *filep, *res; 322 struct nfs_server *server; 323 struct inode *r_ino = NULL; 324 struct nfs_open_context *ctx; 325 struct nfs4_state_owner *sp; 326 char *read_name = NULL; 327 int len, status = 0; 328 329 server = NFS_SERVER(ss_mnt->mnt_root->d_inode); 330 331 if (!fattr) 332 return ERR_PTR(-ENOMEM); 333 334 status = nfs4_proc_getattr(server, src_fh, fattr, NULL); 335 if (status < 0) { 336 res = ERR_PTR(status); 337 goto out; 338 } 339 340 res = ERR_PTR(-ENOMEM); 341 len = strlen(SSC_READ_NAME_BODY) + 16; 342 read_name = kzalloc(len, GFP_NOFS); 343 if (read_name == NULL) 344 goto out; 345 snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); 346 347 r_ino = nfs_fhget(ss_mnt->mnt_root->d_inode->i_sb, src_fh, fattr); 348 if (IS_ERR(r_ino)) { 349 res = ERR_CAST(r_ino); 350 goto out_free_name; 351 } 352 353 filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY, 354 r_ino->i_fop); 355 if (IS_ERR(filep)) { 356 res = ERR_CAST(filep); 357 goto out_free_name; 358 } 359 360 ctx = alloc_nfs_open_context(filep->f_path.dentry, filep->f_mode, 361 filep); 362 if (IS_ERR(ctx)) { 363 res = ERR_CAST(ctx); 364 goto out_filep; 365 } 366 367 res = ERR_PTR(-EINVAL); 368 sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL); 369 if (sp == NULL) 370 goto out_ctx; 371 372 ctx->state = nfs4_get_open_state(r_ino, sp); 373 if (ctx->state == NULL) 374 goto out_stateowner; 375 376 set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags); 377 memcpy(&ctx->state->open_stateid.other, &stateid->other, 378 NFS4_STATEID_OTHER_SIZE); 379 update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); 380 set_bit(NFS_OPEN_STATE, &ctx->state->flags); 381 382 nfs_file_set_open_context(filep, ctx); 383 put_nfs_open_context(ctx); 384 385 file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping); 386 res = filep; 387 out_free_name: 388 kfree(read_name); 389 out: 390 nfs_free_fattr(fattr); 391 return res; 392 out_stateowner: 393 nfs4_put_state_owner(sp); 394 out_ctx: 395 put_nfs_open_context(ctx); 396 out_filep: 397 fput(filep); 398 goto out_free_name; 399 } 400 401 static void __nfs42_ssc_close(struct file *filep) 402 { 403 struct nfs_open_context *ctx = nfs_file_open_context(filep); 404 405 ctx->state->flags = 0; 406 } 407 408 static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = { 409 .sco_open = __nfs42_ssc_open, 410 .sco_close = __nfs42_ssc_close, 411 }; 412 413 /** 414 * nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common 415 * 416 * Return values: 417 * None 418 */ 419 void nfs42_ssc_register_ops(void) 420 { 421 nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl); 422 } 423 424 /** 425 * nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common 426 * 427 * Return values: 428 * None. 429 */ 430 void nfs42_ssc_unregister_ops(void) 431 { 432 nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl); 433 } 434 #endif /* CONFIG_NFS_V4_2 */ 435 436 static int nfs4_setlease(struct file *file, long arg, struct file_lock **lease, 437 void **priv) 438 { 439 return nfs4_proc_setlease(file, arg, lease, priv); 440 } 441 442 const struct file_operations nfs4_file_operations = { 443 .read_iter = nfs_file_read, 444 .write_iter = nfs_file_write, 445 .mmap = nfs_file_mmap, 446 .open = nfs4_file_open, 447 .flush = nfs4_file_flush, 448 .release = nfs_file_release, 449 .fsync = nfs_file_fsync, 450 .lock = nfs_lock, 451 .flock = nfs_flock, 452 .splice_read = generic_file_splice_read, 453 .splice_write = iter_file_splice_write, 454 .check_flags = nfs_check_flags, 455 .setlease = nfs4_setlease, 456 #ifdef CONFIG_NFS_V4_2 457 .copy_file_range = nfs4_copy_file_range, 458 .llseek = nfs4_file_llseek, 459 .fallocate = nfs42_fallocate, 460 .remap_file_range = nfs42_remap_file_range, 461 #else 462 .llseek = nfs_file_llseek, 463 #endif 464 }; 465