1 /* 2 * linux/fs/nfs/file.c 3 * 4 * Copyright (C) 1992 Rick Sladkey 5 */ 6 #include <linux/nfs_fs.h> 7 #include "internal.h" 8 #include "fscache.h" 9 #include "pnfs.h" 10 11 #define NFSDBG_FACILITY NFSDBG_FILE 12 13 static int 14 nfs4_file_open(struct inode *inode, struct file *filp) 15 { 16 struct nfs_open_context *ctx; 17 struct dentry *dentry = filp->f_path.dentry; 18 struct dentry *parent = NULL; 19 struct inode *dir; 20 unsigned openflags = filp->f_flags; 21 struct iattr attr; 22 int opened = 0; 23 int err; 24 25 /* 26 * If no cached dentry exists or if it's negative, NFSv4 handled the 27 * opens in ->lookup() or ->create(). 28 * 29 * We only get this far for a cached positive dentry. We skipped 30 * revalidation, so handle it here by dropping the dentry and returning 31 * -EOPENSTALE. The VFS will retry the lookup/create/open. 32 */ 33 34 dprintk("NFS: open file(%pd2)\n", dentry); 35 36 if ((openflags & O_ACCMODE) == 3) 37 openflags--; 38 39 /* We can't create new files here */ 40 openflags &= ~(O_CREAT|O_EXCL); 41 42 parent = dget_parent(dentry); 43 dir = parent->d_inode; 44 45 ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); 46 err = PTR_ERR(ctx); 47 if (IS_ERR(ctx)) 48 goto out; 49 50 attr.ia_valid = ATTR_OPEN; 51 if (openflags & O_TRUNC) { 52 attr.ia_valid |= ATTR_SIZE; 53 attr.ia_size = 0; 54 nfs_wb_all(inode); 55 } 56 57 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, &opened); 58 if (IS_ERR(inode)) { 59 err = PTR_ERR(inode); 60 switch (err) { 61 case -EPERM: 62 case -EACCES: 63 case -EDQUOT: 64 case -ENOSPC: 65 case -EROFS: 66 goto out_put_ctx; 67 default: 68 goto out_drop; 69 } 70 } 71 if (inode != dentry->d_inode) 72 goto out_drop; 73 74 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 75 nfs_file_set_open_context(filp, ctx); 76 nfs_fscache_open_file(inode, filp); 77 err = 0; 78 79 out_put_ctx: 80 put_nfs_open_context(ctx); 81 out: 82 dput(parent); 83 return err; 84 85 out_drop: 86 d_drop(dentry); 87 err = -EOPENSTALE; 88 goto out_put_ctx; 89 } 90 91 static int 92 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 93 { 94 int ret; 95 struct inode *inode = file_inode(file); 96 97 do { 98 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 99 if (ret != 0) 100 break; 101 mutex_lock(&inode->i_mutex); 102 ret = nfs_file_fsync_commit(file, start, end, datasync); 103 if (!ret) 104 ret = pnfs_layoutcommit_inode(inode, true); 105 mutex_unlock(&inode->i_mutex); 106 /* 107 * If nfs_file_fsync_commit detected a server reboot, then 108 * resend all dirty pages that might have been covered by 109 * the NFS_CONTEXT_RESEND_WRITES flag 110 */ 111 start = 0; 112 end = LLONG_MAX; 113 } while (ret == -EAGAIN); 114 115 return ret; 116 } 117 118 const struct file_operations nfs4_file_operations = { 119 .llseek = nfs_file_llseek, 120 .read = new_sync_read, 121 .write = new_sync_write, 122 .read_iter = nfs_file_read, 123 .write_iter = nfs_file_write, 124 .mmap = nfs_file_mmap, 125 .open = nfs4_file_open, 126 .flush = nfs_file_flush, 127 .release = nfs_file_release, 128 .fsync = nfs4_file_fsync, 129 .lock = nfs_lock, 130 .flock = nfs_flock, 131 .splice_read = nfs_file_splice_read, 132 .splice_write = iter_file_splice_write, 133 .check_flags = nfs_check_flags, 134 .setlease = nfs_setlease, 135 }; 136