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