// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/nfs/file.c * * Copyright (C) 1992 Rick Sladkey */ #include <linux/fs.h> #include <linux/file.h> #include <linux/falloc.h> #include <linux/mount.h> #include <linux/nfs_fs.h> #include <linux/nfs_ssc.h> #include "delegation.h" #include "internal.h" #include "iostat.h" #include "fscache.h" #include "pnfs.h" #include "nfstrace.h" #ifdef CONFIG_NFS_V4_2 #include "nfs42.h" #endif #define NFSDBG_FACILITY NFSDBG_FILE static int nfs4_file_open(struct inode *inode, struct file *filp) { struct nfs_open_context *ctx; struct dentry *dentry = file_dentry(filp); struct dentry *parent = NULL; struct inode *dir; unsigned openflags = filp->f_flags; fmode_t f_mode; struct iattr attr; int err; /* * If no cached dentry exists or if it's negative, NFSv4 handled the * opens in ->lookup() or ->create(). * * We only get this far for a cached positive dentry. We skipped * revalidation, so handle it here by dropping the dentry and returning * -EOPENSTALE. The VFS will retry the lookup/create/open. */ dprintk("NFS: open file(%pd2)\n", dentry); err = nfs_check_flags(openflags); if (err) return err; f_mode = filp->f_mode; if ((openflags & O_ACCMODE) == 3) f_mode |= flags_to_mode(openflags); /* We can't create new files here */ openflags &= ~(O_CREAT|O_EXCL); parent = dget_parent(dentry); dir = d_inode(parent); ctx = alloc_nfs_open_context(file_dentry(filp), f_mode, filp); err = PTR_ERR(ctx); if (IS_ERR(ctx)) goto out; attr.ia_valid = ATTR_OPEN; if (openflags & O_TRUNC) { attr.ia_valid |= ATTR_SIZE; attr.ia_size = 0; filemap_write_and_wait(inode->i_mapping); } inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL); if (IS_ERR(inode)) { err = PTR_ERR(inode); switch (err) { default: goto out_put_ctx; case -ENOENT: case -ESTALE: case -EISDIR: case -ENOTDIR: case -ELOOP: goto out_drop; } } if (inode != d_inode(dentry)) goto out_drop; nfs_file_set_open_context(filp, ctx); nfs_fscache_open_file(inode, filp); err = 0; filp->f_mode |= FMODE_CAN_ODIRECT; out_put_ctx: put_nfs_open_context(ctx); out: dput(parent); return err; out_drop: d_drop(dentry); err = -EOPENSTALE; goto out_put_ctx; } /* * Flush all dirty pages, and check for write errors. */ static int nfs4_file_flush(struct file *file, fl_owner_t id) { struct inode *inode = file_inode(file); errseq_t since; dprintk("NFS: flush(%pD2)\n", file); nfs_inc_stats(inode, NFSIOS_VFSFLUSH); if ((file->f_mode & FMODE_WRITE) == 0) return 0; /* * If we're holding a write delegation, then check if we're required * to flush the i/o on close. If not, then just start the i/o now. */ if (!nfs4_delegation_flush_on_close(inode)) return filemap_fdatawrite(file->f_mapping); /* Flush writes to the server and return any errors */ since = filemap_sample_wb_err(file->f_mapping); nfs_wb_all(inode); return filemap_check_wb_err(file->f_mapping, since); } #ifdef CONFIG_NFS_V4_2 static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t count, unsigned int flags) { struct nfs42_copy_notify_res *cn_resp = NULL; struct nl4_server *nss = NULL; nfs4_stateid *cnrs = NULL; ssize_t ret; bool sync = false; /* Only offload copy if superblock is the same */ if (file_in->f_op != &nfs4_file_operations) return -EXDEV; if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) || !nfs_server_capable(file_inode(file_in), NFS_CAP_COPY)) return -EOPNOTSUPP; if (file_inode(file_in) == file_inode(file_out)) return -EOPNOTSUPP; /* if the copy size if smaller than 2 RPC payloads, make it * synchronous */ if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize) sync = true; retry: if (!nfs42_files_from_same_server(file_in, file_out)) { /* * for inter copy, if copy size is too small * then fallback to generic copy. */ if (sync) return -EOPNOTSUPP; cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res), GFP_KERNEL); if (unlikely(cn_resp == NULL)) return -ENOMEM; ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp); if (ret) { ret = -EOPNOTSUPP; goto out; } nss = &cn_resp->cnr_src; cnrs = &cn_resp->cnr_stateid; } ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count, nss, cnrs, sync); out: kfree(cn_resp); if (ret == -EAGAIN) goto retry; return ret; } static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, size_t count, unsigned int flags) { ssize_t ret; ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count, flags); if (ret == -EOPNOTSUPP || ret == -EXDEV) ret = generic_copy_file_range(file_in, pos_in, file_out, pos_out, count, flags); return ret; } static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) { loff_t ret; switch (whence) { case SEEK_HOLE: case SEEK_DATA: ret = nfs42_proc_llseek(filep, offset, whence); if (ret != -EOPNOTSUPP) return ret; fallthrough; default: return nfs_file_llseek(filep, offset, whence); } } static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) { struct inode *inode = file_inode(filep); long ret; if (!S_ISREG(inode->i_mode)) return -EOPNOTSUPP; if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) return -EOPNOTSUPP; ret = inode_newsize_ok(inode, offset + len); if (ret < 0) return ret; if (mode & FALLOC_FL_PUNCH_HOLE) return nfs42_proc_deallocate(filep, offset, len); return nfs42_proc_allocate(filep, offset, len); } static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off, struct file *dst_file, loff_t dst_off, loff_t count, unsigned int remap_flags) { struct inode *dst_inode = file_inode(dst_file); struct nfs_server *server = NFS_SERVER(dst_inode); struct inode *src_inode = file_inode(src_file); unsigned int bs = server->clone_blksize; bool same_inode = false; int ret; /* NFS does not support deduplication. */ if (remap_flags & REMAP_FILE_DEDUP) return -EOPNOTSUPP; if (remap_flags & ~REMAP_FILE_ADVISORY) return -EINVAL; if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode)) return -ETXTBSY; /* check alignment w.r.t. clone_blksize */ ret = -EINVAL; if (bs) { if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs)) goto out; if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count)) goto out; } if (src_inode == dst_inode) same_inode = true; /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */ if (same_inode) { inode_lock(src_inode); } else if (dst_inode < src_inode) { inode_lock_nested(dst_inode, I_MUTEX_PARENT); inode_lock_nested(src_inode, I_MUTEX_CHILD); } else { inode_lock_nested(src_inode, I_MUTEX_PARENT); inode_lock_nested(dst_inode, I_MUTEX_CHILD); } /* flush all pending writes on both src and dst so that server * has the latest data */ ret = nfs_sync_inode(src_inode); if (ret) goto out_unlock; ret = nfs_sync_inode(dst_inode); if (ret) goto out_unlock; ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count); /* truncate inode page cache of the dst range so that future reads can fetch * new data from server */ if (!ret) truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1); out_unlock: if (same_inode) { inode_unlock(src_inode); } else if (dst_inode < src_inode) { inode_unlock(src_inode); inode_unlock(dst_inode); } else { inode_unlock(dst_inode); inode_unlock(src_inode); } out: return ret < 0 ? ret : count; } static int read_name_gen = 1; #define SSC_READ_NAME_BODY "ssc_read_%d" static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt, struct nfs_fh *src_fh, nfs4_stateid *stateid) { struct nfs_fattr *fattr = nfs_alloc_fattr(); struct file *filep, *res; struct nfs_server *server; struct inode *r_ino = NULL; struct nfs_open_context *ctx; struct nfs4_state_owner *sp; char *read_name = NULL; int len, status = 0; server = NFS_SB(ss_mnt->mnt_sb); if (!fattr) return ERR_PTR(-ENOMEM); status = nfs4_proc_getattr(server, src_fh, fattr, NULL); if (status < 0) { res = ERR_PTR(status); goto out; } res = ERR_PTR(-ENOMEM); len = strlen(SSC_READ_NAME_BODY) + 16; read_name = kzalloc(len, GFP_KERNEL); if (read_name == NULL) goto out; snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++); r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr); if (IS_ERR(r_ino)) { res = ERR_CAST(r_ino); goto out_free_name; } filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY, r_ino->i_fop); if (IS_ERR(filep)) { res = ERR_CAST(filep); goto out_free_name; } ctx = alloc_nfs_open_context(filep->f_path.dentry, filep->f_mode, filep); if (IS_ERR(ctx)) { res = ERR_CAST(ctx); goto out_filep; } res = ERR_PTR(-EINVAL); sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL); if (sp == NULL) goto out_ctx; ctx->state = nfs4_get_open_state(r_ino, sp); if (ctx->state == NULL) goto out_stateowner; set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags); memcpy(&ctx->state->open_stateid.other, &stateid->other, NFS4_STATEID_OTHER_SIZE); update_open_stateid(ctx->state, stateid, NULL, filep->f_mode); set_bit(NFS_OPEN_STATE, &ctx->state->flags); nfs_file_set_open_context(filep, ctx); put_nfs_open_context(ctx); file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping); res = filep; out_free_name: kfree(read_name); out: nfs_free_fattr(fattr); return res; out_stateowner: nfs4_put_state_owner(sp); out_ctx: put_nfs_open_context(ctx); out_filep: fput(filep); goto out_free_name; } static void __nfs42_ssc_close(struct file *filep) { struct nfs_open_context *ctx = nfs_file_open_context(filep); ctx->state->flags = 0; } static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = { .sco_open = __nfs42_ssc_open, .sco_close = __nfs42_ssc_close, }; /** * nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common * * Return values: * None */ void nfs42_ssc_register_ops(void) { nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl); } /** * nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common * * Return values: * None. */ void nfs42_ssc_unregister_ops(void) { nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl); } #endif /* CONFIG_NFS_V4_2 */ static int nfs4_setlease(struct file *file, long arg, struct file_lock **lease, void **priv) { return nfs4_proc_setlease(file, arg, lease, priv); } const struct file_operations nfs4_file_operations = { .read_iter = nfs_file_read, .write_iter = nfs_file_write, .mmap = nfs_file_mmap, .open = nfs4_file_open, .flush = nfs4_file_flush, .release = nfs_file_release, .fsync = nfs_file_fsync, .lock = nfs_lock, .flock = nfs_flock, .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .check_flags = nfs_check_flags, .setlease = nfs4_setlease, #ifdef CONFIG_NFS_V4_2 .copy_file_range = nfs4_copy_file_range, .llseek = nfs4_file_llseek, .fallocate = nfs42_fallocate, .remap_file_range = nfs42_remap_file_range, #else .llseek = nfs_file_llseek, #endif };