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 fmode_t f_mode; 36 struct iattr attr; 37 int err; 38 39 /* 40 * If no cached dentry exists or if it's negative, NFSv4 handled the 41 * opens in ->lookup() or ->create(). 42 * 43 * We only get this far for a cached positive dentry. We skipped 44 * revalidation, so handle it here by dropping the dentry and returning 45 * -EOPENSTALE. The VFS will retry the lookup/create/open. 46 */ 47 48 dprintk("NFS: open file(%pd2)\n", dentry); 49 50 err = nfs_check_flags(openflags); 51 if (err) 52 return err; 53 54 f_mode = filp->f_mode; 55 if ((openflags & O_ACCMODE) == 3) 56 f_mode |= flags_to_mode(openflags); 57 58 /* We can't create new files here */ 59 openflags &= ~(O_CREAT|O_EXCL); 60 61 parent = dget_parent(dentry); 62 dir = d_inode(parent); 63 64 ctx = alloc_nfs_open_context(file_dentry(filp), f_mode, filp); 65 err = PTR_ERR(ctx); 66 if (IS_ERR(ctx)) 67 goto out; 68 69 attr.ia_valid = ATTR_OPEN; 70 if (openflags & O_TRUNC) { 71 attr.ia_valid |= ATTR_SIZE; 72 attr.ia_size = 0; 73 filemap_write_and_wait(inode->i_mapping); 74 } 75 76 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL); 77 if (IS_ERR(inode)) { 78 err = PTR_ERR(inode); 79 switch (err) { 80 default: 81 goto out_put_ctx; 82 case -ENOENT: 83 case -ESTALE: 84 case -EISDIR: 85 case -ENOTDIR: 86 case -ELOOP: 87 goto out_drop; 88 } 89 } 90 if (inode != d_inode(dentry)) 91 goto out_drop; 92 93 nfs_file_set_open_context(filp, ctx); 94 nfs_fscache_open_file(inode, filp); 95 err = 0; 96 filp->f_mode |= FMODE_CAN_ODIRECT; 97 98 out_put_ctx: 99 put_nfs_open_context(ctx); 100 out: 101 dput(parent); 102 return err; 103 104 out_drop: 105 d_drop(dentry); 106 err = -EOPENSTALE; 107 goto out_put_ctx; 108 } 109 110 /* 111 * Flush all dirty pages, and check for write errors. 112 */ 113 static int 114 nfs4_file_flush(struct file *file, fl_owner_t id) 115 { 116 struct inode *inode = file_inode(file); 117 errseq_t since; 118 119 dprintk("NFS: flush(%pD2)\n", file); 120 121 nfs_inc_stats(inode, NFSIOS_VFSFLUSH); 122 if ((file->f_mode & FMODE_WRITE) == 0) 123 return 0; 124 125 /* 126 * If we're holding a write delegation, then check if we're required 127 * to flush the i/o on close. If not, then just start the i/o now. 128 */ 129 if (!nfs4_delegation_flush_on_close(inode)) 130 return filemap_fdatawrite(file->f_mapping); 131 132 /* Flush writes to the server and return any errors */ 133 since = filemap_sample_wb_err(file->f_mapping); 134 nfs_wb_all(inode); 135 return filemap_check_wb_err(file->f_mapping, since); 136 } 137 138 #ifdef CONFIG_NFS_V4_2 139 static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, 140 struct file *file_out, loff_t pos_out, 141 size_t count, unsigned int flags) 142 { 143 struct nfs42_copy_notify_res *cn_resp = NULL; 144 struct nl4_server *nss = NULL; 145 nfs4_stateid *cnrs = NULL; 146 ssize_t ret; 147 bool sync = false; 148 149 /* Only offload copy if superblock is the same */ 150 if (file_in->f_op != &nfs4_file_operations) 151 return -EXDEV; 152 if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) || 153 !nfs_server_capable(file_inode(file_in), NFS_CAP_COPY)) 154 return -EOPNOTSUPP; 155 if (file_inode(file_in) == file_inode(file_out)) 156 return -EOPNOTSUPP; 157 /* if the copy size if smaller than 2 RPC payloads, make it 158 * synchronous 159 */ 160 if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize) 161 sync = true; 162 retry: 163 if (!nfs42_files_from_same_server(file_in, file_out)) { 164 /* 165 * for inter copy, if copy size is too small 166 * then fallback to generic copy. 167 */ 168 if (sync) 169 return -EOPNOTSUPP; 170 cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res), 171 GFP_KERNEL); 172 if (unlikely(cn_resp == NULL)) 173 return -ENOMEM; 174 175 ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp); 176 if (ret) { 177 ret = -EOPNOTSUPP; 178 goto out; 179 } 180 nss = &cn_resp->cnr_src; 181 cnrs = &cn_resp->cnr_stateid; 182 } 183 ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count, 184 nss, cnrs, sync); 185 out: 186 kfree(cn_resp); 187 188 if (ret == -EAGAIN) 189 goto retry; 190 return ret; 191 } 192 193 static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, 194 struct file *file_out, loff_t pos_out, 195 size_t count, unsigned int flags) 196 { 197 ssize_t ret; 198 199 ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, 200 flags); 201 if (ret == -EOPNOTSUPP || ret == -EXDEV) 202 ret = generic_copy_file_range(file_in, pos_in, file_out, 203 pos_out, count, flags); 204 return ret; 205 } 206 207 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 208 { 209 loff_t ret; 210 211 switch (whence) { 212 case SEEK_HOLE: 213 case SEEK_DATA: 214 ret = nfs42_proc_llseek(filep, offset, whence); 215 if (ret != -EOPNOTSUPP) 216 return ret; 217 fallthrough; 218 default: 219 return nfs_file_llseek(filep, offset, whence); 220 } 221 } 222 223 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 224 { 225 struct inode *inode = file_inode(filep); 226 long ret; 227 228 if (!S_ISREG(inode->i_mode)) 229 return -EOPNOTSUPP; 230 231 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 232 return -EOPNOTSUPP; 233 234 ret = inode_newsize_ok(inode, offset + len); 235 if (ret < 0) 236 return ret; 237 238 if (mode & FALLOC_FL_PUNCH_HOLE) 239 return nfs42_proc_deallocate(filep, offset, len); 240 return nfs42_proc_allocate(filep, offset, len); 241 } 242 243 static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, 244 struct file *dst_file, loff_t dst_off, loff_t count, 245 unsigned int remap_flags) 246 { 247 struct inode *dst_inode = file_inode(dst_file); 248 struct nfs_server *server = NFS_SERVER(dst_inode); 249 struct inode *src_inode = file_inode(src_file); 250 unsigned int bs = server->clone_blksize; 251 bool same_inode = false; 252 int ret; 253 254 /* NFS does not support deduplication. */ 255 if (remap_flags & REMAP_FILE_DEDUP) 256 return -EOPNOTSUPP; 257 258 if (remap_flags & ~REMAP_FILE_ADVISORY) 259 return -EINVAL; 260 261 if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode)) 262 return -ETXTBSY; 263 264 /* check alignment w.r.t. clone_blksize */ 265 ret = -EINVAL; 266 if (bs) { 267 if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs)) 268 goto out; 269 if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count)) 270 goto out; 271 } 272 273 if (src_inode == dst_inode) 274 same_inode = true; 275 276 /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */ 277 if (same_inode) { 278 inode_lock(src_inode); 279 } else if (dst_inode < src_inode) { 280 inode_lock_nested(dst_inode, I_MUTEX_PARENT); 281 inode_lock_nested(src_inode, I_MUTEX_CHILD); 282 } else { 283 inode_lock_nested(src_inode, I_MUTEX_PARENT); 284 inode_lock_nested(dst_inode, I_MUTEX_CHILD); 285 } 286 287 /* flush all pending writes on both src and dst so that server 288 * has the latest data */ 289 ret = nfs_sync_inode(src_inode); 290 if (ret) 291 goto out_unlock; 292 ret = nfs_sync_inode(dst_inode); 293 if (ret) 294 goto out_unlock; 295 296 ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count); 297 298 /* truncate inode page cache of the dst range so that future reads can fetch 299 * new data from server */ 300 if (!ret) 301 truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1); 302 303 out_unlock: 304 if (same_inode) { 305 inode_unlock(src_inode); 306 } else if (dst_inode < src_inode) { 307 inode_unlock(src_inode); 308 inode_unlock(dst_inode); 309 } else { 310 inode_unlock(dst_inode); 311 inode_unlock(src_inode); 312 } 313 out: 314 return ret < 0 ? ret : count; 315 } 316 317 static int read_name_gen = 1; 318 #define SSC_READ_NAME_BODY "ssc_read_%d" 319 320 static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, 321 struct nfs_fh *src_fh, nfs4_stateid *stateid) 322 { 323 struct nfs_fattr *fattr = nfs_alloc_fattr(); 324 struct file *filep, *res; 325 struct nfs_server *server; 326 struct inode *r_ino = NULL; 327 struct nfs_open_context *ctx; 328 struct nfs4_state_owner *sp; 329 char *read_name = NULL; 330 int len, status = 0; 331 332 server = NFS_SB(ss_mnt->mnt_sb); 333 334 if (!fattr) 335 return ERR_PTR(-ENOMEM); 336 337 status = nfs4_proc_getattr(server, src_fh, fattr, NULL); 338 if (status < 0) { 339 res = ERR_PTR(status); 340 goto out; 341 } 342 343 if (!S_ISREG(fattr->mode)) { 344 res = ERR_PTR(-EBADF); 345 goto out; 346 } 347 348 res = ERR_PTR(-ENOMEM); 349 len = strlen(SSC_READ_NAME_BODY) + 16; 350 read_name = kzalloc(len, GFP_KERNEL); 351 if (read_name == NULL) 352 goto out; 353 snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); 354 355 r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr); 356 if (IS_ERR(r_ino)) { 357 res = ERR_CAST(r_ino); 358 goto out_free_name; 359 } 360 361 filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY, 362 r_ino->i_fop); 363 if (IS_ERR(filep)) { 364 res = ERR_CAST(filep); 365 iput(r_ino); 366 goto out_free_name; 367 } 368 369 ctx = alloc_nfs_open_context(filep->f_path.dentry, filep->f_mode, 370 filep); 371 if (IS_ERR(ctx)) { 372 res = ERR_CAST(ctx); 373 goto out_filep; 374 } 375 376 res = ERR_PTR(-EINVAL); 377 sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL); 378 if (sp == NULL) 379 goto out_ctx; 380 381 ctx->state = nfs4_get_open_state(r_ino, sp); 382 if (ctx->state == NULL) 383 goto out_stateowner; 384 385 set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags); 386 memcpy(&ctx->state->open_stateid.other, &stateid->other, 387 NFS4_STATEID_OTHER_SIZE); 388 update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); 389 set_bit(NFS_OPEN_STATE, &ctx->state->flags); 390 391 nfs_file_set_open_context(filep, ctx); 392 put_nfs_open_context(ctx); 393 394 file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping); 395 res = filep; 396 out_free_name: 397 kfree(read_name); 398 out: 399 nfs_free_fattr(fattr); 400 return res; 401 out_stateowner: 402 nfs4_put_state_owner(sp); 403 out_ctx: 404 put_nfs_open_context(ctx); 405 out_filep: 406 fput(filep); 407 goto out_free_name; 408 } 409 410 static void __nfs42_ssc_close(struct file *filep) 411 { 412 struct nfs_open_context *ctx = nfs_file_open_context(filep); 413 414 ctx->state->flags = 0; 415 } 416 417 static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = { 418 .sco_open = __nfs42_ssc_open, 419 .sco_close = __nfs42_ssc_close, 420 }; 421 422 /** 423 * nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common 424 * 425 * Return values: 426 * None 427 */ 428 void nfs42_ssc_register_ops(void) 429 { 430 nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl); 431 } 432 433 /** 434 * nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common 435 * 436 * Return values: 437 * None. 438 */ 439 void nfs42_ssc_unregister_ops(void) 440 { 441 nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl); 442 } 443 #endif /* CONFIG_NFS_V4_2 */ 444 445 static int nfs4_setlease(struct file *file, long arg, struct file_lock **lease, 446 void **priv) 447 { 448 return nfs4_proc_setlease(file, arg, lease, priv); 449 } 450 451 const struct file_operations nfs4_file_operations = { 452 .read_iter = nfs_file_read, 453 .write_iter = nfs_file_write, 454 .mmap = nfs_file_mmap, 455 .open = nfs4_file_open, 456 .flush = nfs4_file_flush, 457 .release = nfs_file_release, 458 .fsync = nfs_file_fsync, 459 .lock = nfs_lock, 460 .flock = nfs_flock, 461 .splice_read = generic_file_splice_read, 462 .splice_write = iter_file_splice_write, 463 .check_flags = nfs_check_flags, 464 .setlease = nfs4_setlease, 465 #ifdef CONFIG_NFS_V4_2 466 .copy_file_range = nfs4_copy_file_range, 467 .llseek = nfs4_file_llseek, 468 .fallocate = nfs42_fallocate, 469 .remap_file_range = nfs42_remap_file_range, 470 #else 471 .llseek = nfs_file_llseek, 472 #endif 473 }; 474