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 /* for inter copy, if copy size if smaller than 12 RPC 162 * payloads, fallback to traditional copy. There are 163 * 14 RPCs during an NFSv4.x mount between source/dest 164 * servers. 165 */ 166 if (sync || 167 count <= 14 * NFS_SERVER(file_inode(file_in))->rsize) 168 return -EOPNOTSUPP; 169 cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res), 170 GFP_NOFS); 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 if (!nfs42_files_from_same_server(file_in, file_out)) 186 kfree(cn_resp); 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 != -ENOTSUPP) 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; 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 nfs_fattr_init(&fattr); 334 335 status = nfs4_proc_getattr(server, src_fh, &fattr, NULL, NULL); 336 if (status < 0) { 337 res = ERR_PTR(status); 338 goto out; 339 } 340 341 res = ERR_PTR(-ENOMEM); 342 len = strlen(SSC_READ_NAME_BODY) + 16; 343 read_name = kzalloc(len, GFP_NOFS); 344 if (read_name == NULL) 345 goto out; 346 snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); 347 348 r_ino = nfs_fhget(ss_mnt->mnt_root->d_inode->i_sb, src_fh, &fattr, 349 NULL); 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, FMODE_READ, 356 r_ino->i_fop); 357 if (IS_ERR(filep)) { 358 res = ERR_CAST(filep); 359 goto out_free_name; 360 } 361 filep->f_mode |= FMODE_READ; 362 363 ctx = alloc_nfs_open_context(filep->f_path.dentry, filep->f_mode, 364 filep); 365 if (IS_ERR(ctx)) { 366 res = ERR_CAST(ctx); 367 goto out_filep; 368 } 369 370 res = ERR_PTR(-EINVAL); 371 sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL); 372 if (sp == NULL) 373 goto out_ctx; 374 375 ctx->state = nfs4_get_open_state(r_ino, sp); 376 if (ctx->state == NULL) 377 goto out_stateowner; 378 379 set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags); 380 set_bit(NFS_OPEN_STATE, &ctx->state->flags); 381 memcpy(&ctx->state->open_stateid.other, &stateid->other, 382 NFS4_STATEID_OTHER_SIZE); 383 update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); 384 385 nfs_file_set_open_context(filep, ctx); 386 put_nfs_open_context(ctx); 387 388 file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping); 389 res = filep; 390 out_free_name: 391 kfree(read_name); 392 out: 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 const struct file_operations nfs4_file_operations = { 439 .read_iter = nfs_file_read, 440 .write_iter = nfs_file_write, 441 .mmap = nfs_file_mmap, 442 .open = nfs4_file_open, 443 .flush = nfs4_file_flush, 444 .release = nfs_file_release, 445 .fsync = nfs_file_fsync, 446 .lock = nfs_lock, 447 .flock = nfs_flock, 448 .splice_read = generic_file_splice_read, 449 .splice_write = iter_file_splice_write, 450 .check_flags = nfs_check_flags, 451 .setlease = simple_nosetlease, 452 #ifdef CONFIG_NFS_V4_2 453 .copy_file_range = nfs4_copy_file_range, 454 .llseek = nfs4_file_llseek, 455 .fallocate = nfs42_fallocate, 456 .remap_file_range = nfs42_remap_file_range, 457 #else 458 .llseek = nfs_file_llseek, 459 #endif 460 }; 461