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 "delegation.h" 13 #include "internal.h" 14 #include "iostat.h" 15 #include "fscache.h" 16 #include "pnfs.h" 17 18 #include "nfstrace.h" 19 20 #ifdef CONFIG_NFS_V4_2 21 #include "nfs42.h" 22 #endif 23 24 #define NFSDBG_FACILITY NFSDBG_FILE 25 26 static int 27 nfs4_file_open(struct inode *inode, struct file *filp) 28 { 29 struct nfs_open_context *ctx; 30 struct dentry *dentry = file_dentry(filp); 31 struct dentry *parent = NULL; 32 struct inode *dir; 33 unsigned openflags = filp->f_flags; 34 struct iattr attr; 35 int err; 36 37 /* 38 * If no cached dentry exists or if it's negative, NFSv4 handled the 39 * opens in ->lookup() or ->create(). 40 * 41 * We only get this far for a cached positive dentry. We skipped 42 * revalidation, so handle it here by dropping the dentry and returning 43 * -EOPENSTALE. The VFS will retry the lookup/create/open. 44 */ 45 46 dprintk("NFS: open file(%pd2)\n", dentry); 47 48 err = nfs_check_flags(openflags); 49 if (err) 50 return err; 51 52 if ((openflags & O_ACCMODE) == 3) 53 return nfs_open(inode, filp); 54 55 /* We can't create new files here */ 56 openflags &= ~(O_CREAT|O_EXCL); 57 58 parent = dget_parent(dentry); 59 dir = d_inode(parent); 60 61 ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode, 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 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 return -EOPNOTSUPP; 150 if (file_inode(file_in) == file_inode(file_out)) 151 return -EOPNOTSUPP; 152 /* if the copy size if smaller than 2 RPC payloads, make it 153 * synchronous 154 */ 155 if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize) 156 sync = true; 157 retry: 158 if (!nfs42_files_from_same_server(file_in, file_out)) { 159 /* for inter copy, if copy size if smaller than 12 RPC 160 * payloads, fallback to traditional copy. There are 161 * 14 RPCs during an NFSv4.x mount between source/dest 162 * servers. 163 */ 164 if (sync || 165 count <= 14 * NFS_SERVER(file_inode(file_in))->rsize) 166 return -EOPNOTSUPP; 167 cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res), 168 GFP_NOFS); 169 if (unlikely(cn_resp == NULL)) 170 return -ENOMEM; 171 172 ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp); 173 if (ret) { 174 ret = -EOPNOTSUPP; 175 goto out; 176 } 177 nss = &cn_resp->cnr_src; 178 cnrs = &cn_resp->cnr_stateid; 179 } 180 ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count, 181 nss, cnrs, sync); 182 out: 183 if (!nfs42_files_from_same_server(file_in, file_out)) 184 kfree(cn_resp); 185 if (ret == -EAGAIN) 186 goto retry; 187 return ret; 188 } 189 190 static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, 191 struct file *file_out, loff_t pos_out, 192 size_t count, unsigned int flags) 193 { 194 ssize_t ret; 195 196 ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, 197 flags); 198 if (ret == -EOPNOTSUPP || ret == -EXDEV) 199 ret = generic_copy_file_range(file_in, pos_in, file_out, 200 pos_out, count, flags); 201 return ret; 202 } 203 204 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 205 { 206 loff_t ret; 207 208 switch (whence) { 209 case SEEK_HOLE: 210 case SEEK_DATA: 211 ret = nfs42_proc_llseek(filep, offset, whence); 212 if (ret != -ENOTSUPP) 213 return ret; 214 fallthrough; 215 default: 216 return nfs_file_llseek(filep, offset, whence); 217 } 218 } 219 220 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 221 { 222 struct inode *inode = file_inode(filep); 223 long ret; 224 225 if (!S_ISREG(inode->i_mode)) 226 return -EOPNOTSUPP; 227 228 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 229 return -EOPNOTSUPP; 230 231 ret = inode_newsize_ok(inode, offset + len); 232 if (ret < 0) 233 return ret; 234 235 if (mode & FALLOC_FL_PUNCH_HOLE) 236 return nfs42_proc_deallocate(filep, offset, len); 237 return nfs42_proc_allocate(filep, offset, len); 238 } 239 240 static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, 241 struct file *dst_file, loff_t dst_off, loff_t count, 242 unsigned int remap_flags) 243 { 244 struct inode *dst_inode = file_inode(dst_file); 245 struct nfs_server *server = NFS_SERVER(dst_inode); 246 struct inode *src_inode = file_inode(src_file); 247 unsigned int bs = server->clone_blksize; 248 bool same_inode = false; 249 int ret; 250 251 /* NFS does not support deduplication. */ 252 if (remap_flags & REMAP_FILE_DEDUP) 253 return -EOPNOTSUPP; 254 255 if (remap_flags & ~REMAP_FILE_ADVISORY) 256 return -EINVAL; 257 258 if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode)) 259 return -ETXTBSY; 260 261 /* check alignment w.r.t. clone_blksize */ 262 ret = -EINVAL; 263 if (bs) { 264 if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs)) 265 goto out; 266 if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count)) 267 goto out; 268 } 269 270 if (src_inode == dst_inode) 271 same_inode = true; 272 273 /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */ 274 if (same_inode) { 275 inode_lock(src_inode); 276 } else if (dst_inode < src_inode) { 277 inode_lock_nested(dst_inode, I_MUTEX_PARENT); 278 inode_lock_nested(src_inode, I_MUTEX_CHILD); 279 } else { 280 inode_lock_nested(src_inode, I_MUTEX_PARENT); 281 inode_lock_nested(dst_inode, I_MUTEX_CHILD); 282 } 283 284 /* flush all pending writes on both src and dst so that server 285 * has the latest data */ 286 ret = nfs_sync_inode(src_inode); 287 if (ret) 288 goto out_unlock; 289 ret = nfs_sync_inode(dst_inode); 290 if (ret) 291 goto out_unlock; 292 293 ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count); 294 295 /* truncate inode page cache of the dst range so that future reads can fetch 296 * new data from server */ 297 if (!ret) 298 truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1); 299 300 out_unlock: 301 if (same_inode) { 302 inode_unlock(src_inode); 303 } else if (dst_inode < src_inode) { 304 inode_unlock(src_inode); 305 inode_unlock(dst_inode); 306 } else { 307 inode_unlock(dst_inode); 308 inode_unlock(src_inode); 309 } 310 out: 311 return ret < 0 ? ret : count; 312 } 313 314 static int read_name_gen = 1; 315 #define SSC_READ_NAME_BODY "ssc_read_%d" 316 317 struct file * 318 nfs42_ssc_open(struct vfsmount *ss_mnt, struct nfs_fh *src_fh, 319 nfs4_stateid *stateid) 320 { 321 struct nfs_fattr fattr; 322 struct file *filep, *res; 323 struct nfs_server *server; 324 struct inode *r_ino = NULL; 325 struct nfs_open_context *ctx; 326 struct nfs4_state_owner *sp; 327 char *read_name = NULL; 328 int len, status = 0; 329 330 server = NFS_SERVER(ss_mnt->mnt_root->d_inode); 331 332 nfs_fattr_init(&fattr); 333 334 status = nfs4_proc_getattr(server, src_fh, &fattr, NULL, NULL); 335 if (status < 0) { 336 res = ERR_PTR(status); 337 goto out; 338 } 339 340 res = ERR_PTR(-ENOMEM); 341 len = strlen(SSC_READ_NAME_BODY) + 16; 342 read_name = kzalloc(len, GFP_NOFS); 343 if (read_name == NULL) 344 goto out; 345 snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); 346 347 r_ino = nfs_fhget(ss_mnt->mnt_root->d_inode->i_sb, src_fh, &fattr, 348 NULL); 349 if (IS_ERR(r_ino)) { 350 res = ERR_CAST(r_ino); 351 goto out_free_name; 352 } 353 354 filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, FMODE_READ, 355 r_ino->i_fop); 356 if (IS_ERR(filep)) { 357 res = ERR_CAST(filep); 358 goto out_free_name; 359 } 360 filep->f_mode |= FMODE_READ; 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 set_bit(NFS_OPEN_STATE, &ctx->state->flags); 380 memcpy(&ctx->state->open_stateid.other, &stateid->other, 381 NFS4_STATEID_OTHER_SIZE); 382 update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); 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 return res; 393 out_stateowner: 394 nfs4_put_state_owner(sp); 395 out_ctx: 396 put_nfs_open_context(ctx); 397 out_filep: 398 fput(filep); 399 goto out_free_name; 400 } 401 EXPORT_SYMBOL_GPL(nfs42_ssc_open); 402 void nfs42_ssc_close(struct file *filep) 403 { 404 struct nfs_open_context *ctx = nfs_file_open_context(filep); 405 406 ctx->state->flags = 0; 407 } 408 EXPORT_SYMBOL_GPL(nfs42_ssc_close); 409 #endif /* CONFIG_NFS_V4_2 */ 410 411 const struct file_operations nfs4_file_operations = { 412 .read_iter = nfs_file_read, 413 .write_iter = nfs_file_write, 414 .mmap = nfs_file_mmap, 415 .open = nfs4_file_open, 416 .flush = nfs4_file_flush, 417 .release = nfs_file_release, 418 .fsync = nfs_file_fsync, 419 .lock = nfs_lock, 420 .flock = nfs_flock, 421 .splice_read = generic_file_splice_read, 422 .splice_write = iter_file_splice_write, 423 .check_flags = nfs_check_flags, 424 .setlease = simple_nosetlease, 425 #ifdef CONFIG_NFS_V4_2 426 .copy_file_range = nfs4_copy_file_range, 427 .llseek = nfs4_file_llseek, 428 .fallocate = nfs42_fallocate, 429 .remap_file_range = nfs42_remap_file_range, 430 #else 431 .llseek = nfs_file_llseek, 432 #endif 433 }; 434