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