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 <linux/splice.h> 14 #include "delegation.h" 15 #include "internal.h" 16 #include "iostat.h" 17 #include "fscache.h" 18 #include "pnfs.h" 19 20 #include "nfstrace.h" 21 22 #ifdef CONFIG_NFS_V4_2 23 #include "nfs42.h" 24 #endif 25 26 #define NFSDBG_FACILITY NFSDBG_FILE 27 28 static int 29 nfs4_file_open(struct inode *inode, struct file *filp) 30 { 31 struct nfs_open_context *ctx; 32 struct dentry *dentry = file_dentry(filp); 33 struct dentry *parent = NULL; 34 struct inode *dir; 35 unsigned openflags = filp->f_flags; 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 /* We can't create new files here */ 55 openflags &= ~(O_CREAT|O_EXCL); 56 57 parent = dget_parent(dentry); 58 dir = d_inode(parent); 59 60 ctx = alloc_nfs_open_context(file_dentry(filp), 61 flags_to_mode(openflags), filp); 62 err = PTR_ERR(ctx); 63 if (IS_ERR(ctx)) 64 goto out; 65 66 attr.ia_valid = ATTR_OPEN; 67 if (openflags & O_TRUNC) { 68 attr.ia_valid |= ATTR_SIZE; 69 attr.ia_size = 0; 70 filemap_write_and_wait(inode->i_mapping); 71 } 72 73 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL); 74 if (IS_ERR(inode)) { 75 err = PTR_ERR(inode); 76 switch (err) { 77 default: 78 goto out_put_ctx; 79 case -ENOENT: 80 case -ESTALE: 81 case -EISDIR: 82 case -ENOTDIR: 83 case -ELOOP: 84 goto out_drop; 85 } 86 } 87 if (inode != d_inode(dentry)) 88 goto out_drop; 89 90 nfs_file_set_open_context(filp, ctx); 91 nfs_fscache_open_file(inode, filp); 92 err = 0; 93 filp->f_mode |= FMODE_CAN_ODIRECT; 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_obj(struct nfs42_copy_notify_res); 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 = splice_copy_file_range(file_in, pos_in, file_out, 199 pos_out, count); 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 switch (mode) { 228 case 0: 229 case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: 230 case FALLOC_FL_ZERO_RANGE: 231 break; 232 default: 233 return -EOPNOTSUPP; 234 } 235 236 ret = inode_newsize_ok(inode, offset + len); 237 if (ret < 0) 238 return ret; 239 240 if (mode & FALLOC_FL_PUNCH_HOLE) 241 return nfs42_proc_deallocate(filep, offset, len); 242 else if (mode & FALLOC_FL_ZERO_RANGE) 243 return nfs42_proc_zero_range(filep, offset ,len); 244 return nfs42_proc_allocate(filep, offset, len); 245 } 246 247 static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, 248 struct file *dst_file, loff_t dst_off, loff_t count, 249 unsigned int remap_flags) 250 { 251 struct inode *dst_inode = file_inode(dst_file); 252 struct nfs_server *server = NFS_SERVER(dst_inode); 253 struct inode *src_inode = file_inode(src_file); 254 unsigned int bs = server->clone_blksize; 255 int ret; 256 257 /* NFS does not support deduplication. */ 258 if (remap_flags & REMAP_FILE_DEDUP) 259 return -EOPNOTSUPP; 260 261 if (remap_flags & ~REMAP_FILE_ADVISORY) 262 return -EINVAL; 263 264 if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode)) 265 return -ETXTBSY; 266 267 /* check alignment w.r.t. clone_blksize */ 268 ret = -EINVAL; 269 if (bs) { 270 if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs)) 271 goto out; 272 if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count)) 273 goto out; 274 } 275 276 /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */ 277 lock_two_nondirectories(src_inode, dst_inode); 278 /* flush all pending writes on both src and dst so that server 279 * has the latest data */ 280 nfs_file_block_o_direct(NFS_I(src_inode)); 281 ret = nfs_sync_inode(src_inode); 282 if (ret) 283 goto out_unlock; 284 nfs_file_block_o_direct(NFS_I(dst_inode)); 285 ret = nfs_sync_inode(dst_inode); 286 if (ret) 287 goto out_unlock; 288 289 ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count); 290 291 /* truncate inode page cache of the dst range so that future reads can fetch 292 * new data from server */ 293 if (!ret) 294 truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1); 295 296 out_unlock: 297 unlock_two_nondirectories(src_inode, dst_inode); 298 out: 299 return ret < 0 ? ret : count; 300 } 301 302 static int read_name_gen = 1; 303 #define SSC_READ_NAME_BODY "ssc_read_%d" 304 305 static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, 306 struct nfs_fh *src_fh, nfs4_stateid *stateid) 307 { 308 struct nfs_fattr *fattr = nfs_alloc_fattr(); 309 struct file *filep, *res; 310 struct nfs_server *server; 311 struct inode *r_ino = NULL; 312 struct nfs_open_context *ctx; 313 struct nfs4_state_owner *sp; 314 char *read_name = NULL; 315 int len, status = 0; 316 317 server = NFS_SB(ss_mnt->mnt_sb); 318 319 if (!fattr) 320 return ERR_PTR(-ENOMEM); 321 322 status = nfs4_proc_getattr(server, src_fh, fattr, NULL); 323 if (status < 0) { 324 res = ERR_PTR(status); 325 goto out; 326 } 327 328 if (!S_ISREG(fattr->mode)) { 329 res = ERR_PTR(-EBADF); 330 goto out; 331 } 332 333 res = ERR_PTR(-ENOMEM); 334 len = strlen(SSC_READ_NAME_BODY) + 16; 335 read_name = kzalloc(len, GFP_KERNEL); 336 if (read_name == NULL) 337 goto out; 338 snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); 339 340 r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr); 341 if (IS_ERR(r_ino)) { 342 res = ERR_CAST(r_ino); 343 goto out_free_name; 344 } 345 346 filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY, 347 r_ino->i_fop); 348 if (IS_ERR(filep)) { 349 res = ERR_CAST(filep); 350 iput(r_ino); 351 goto out_free_name; 352 } 353 354 ctx = alloc_nfs_open_context(filep->f_path.dentry, 355 flags_to_mode(filep->f_flags), filep); 356 if (IS_ERR(ctx)) { 357 res = ERR_CAST(ctx); 358 goto out_filep; 359 } 360 361 res = ERR_PTR(-EINVAL); 362 sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL); 363 if (sp == NULL) 364 goto out_ctx; 365 366 ctx->state = nfs4_get_open_state(r_ino, sp); 367 if (ctx->state == NULL) 368 goto out_stateowner; 369 370 set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags); 371 memcpy(&ctx->state->open_stateid.other, &stateid->other, 372 NFS4_STATEID_OTHER_SIZE); 373 update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); 374 set_bit(NFS_OPEN_STATE, &ctx->state->flags); 375 376 nfs_file_set_open_context(filep, ctx); 377 put_nfs_open_context(ctx); 378 379 file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping); 380 res = filep; 381 out_free_name: 382 kfree(read_name); 383 out: 384 nfs_free_fattr(fattr); 385 return res; 386 out_stateowner: 387 nfs4_put_state_owner(sp); 388 out_ctx: 389 put_nfs_open_context(ctx); 390 out_filep: 391 fput(filep); 392 goto out_free_name; 393 } 394 395 static void __nfs42_ssc_close(struct file *filep) 396 { 397 struct nfs_open_context *ctx = nfs_file_open_context(filep); 398 399 ctx->state->flags = 0; 400 } 401 402 static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = { 403 .sco_open = __nfs42_ssc_open, 404 .sco_close = __nfs42_ssc_close, 405 }; 406 407 /** 408 * nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common 409 * 410 * Return values: 411 * None 412 */ 413 void nfs42_ssc_register_ops(void) 414 { 415 nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl); 416 } 417 418 /** 419 * nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common 420 * 421 * Return values: 422 * None. 423 */ 424 void nfs42_ssc_unregister_ops(void) 425 { 426 nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl); 427 } 428 #endif /* CONFIG_NFS_V4_2 */ 429 430 static int nfs4_setlease(struct file *file, int arg, struct file_lease **lease, 431 void **priv) 432 { 433 return nfs4_proc_setlease(file, arg, lease, priv); 434 } 435 436 const struct file_operations nfs4_file_operations = { 437 .read_iter = nfs_file_read, 438 .write_iter = nfs_file_write, 439 .mmap_prepare = nfs_file_mmap_prepare, 440 .open = nfs4_file_open, 441 .flush = nfs4_file_flush, 442 .release = nfs_file_release, 443 .fsync = nfs_file_fsync, 444 .lock = nfs_lock, 445 .flock = nfs_flock, 446 .splice_read = nfs_file_splice_read, 447 .splice_write = iter_file_splice_write, 448 .check_flags = nfs_check_flags, 449 .setlease = nfs4_setlease, 450 #ifdef CONFIG_NFS_V4_2 451 .copy_file_range = nfs4_copy_file_range, 452 .llseek = nfs4_file_llseek, 453 .fallocate = nfs42_fallocate, 454 .remap_file_range = nfs42_remap_file_range, 455 #else 456 .llseek = nfs_file_llseek, 457 #endif 458 .fop_flags = FOP_DONTCACHE, 459 }; 460