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 err; 23 24 /* 25 * If no cached dentry exists or if it's negative, NFSv4 handled the 26 * opens in ->lookup() or ->create(). 27 * 28 * We only get this far for a cached positive dentry. We skipped 29 * revalidation, so handle it here by dropping the dentry and returning 30 * -EOPENSTALE. The VFS will retry the lookup/create/open. 31 */ 32 33 dprintk("NFS: open file(%s/%s)\n", 34 dentry->d_parent->d_name.name, 35 dentry->d_name.name); 36 37 if ((openflags & O_ACCMODE) == 3) 38 openflags--; 39 40 /* We can't create new files here */ 41 openflags &= ~(O_CREAT|O_EXCL); 42 43 parent = dget_parent(dentry); 44 dir = parent->d_inode; 45 46 ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); 47 err = PTR_ERR(ctx); 48 if (IS_ERR(ctx)) 49 goto out; 50 51 attr.ia_valid = ATTR_OPEN; 52 if (openflags & O_TRUNC) { 53 attr.ia_valid |= ATTR_SIZE; 54 attr.ia_size = 0; 55 nfs_wb_all(inode); 56 } 57 58 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr); 59 if (IS_ERR(inode)) { 60 err = PTR_ERR(inode); 61 switch (err) { 62 case -EPERM: 63 case -EACCES: 64 case -EDQUOT: 65 case -ENOSPC: 66 case -EROFS: 67 goto out_put_ctx; 68 default: 69 goto out_drop; 70 } 71 } 72 iput(inode); 73 if (inode != dentry->d_inode) 74 goto out_drop; 75 76 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 77 nfs_file_set_open_context(filp, ctx); 78 nfs_fscache_set_inode_cookie(inode, filp); 79 err = 0; 80 81 out_put_ctx: 82 put_nfs_open_context(ctx); 83 out: 84 dput(parent); 85 return err; 86 87 out_drop: 88 d_drop(dentry); 89 err = -EOPENSTALE; 90 goto out_put_ctx; 91 } 92 93 static int 94 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 95 { 96 int ret; 97 struct inode *inode = file->f_path.dentry->d_inode; 98 99 do { 100 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 101 if (ret != 0) 102 break; 103 mutex_lock(&inode->i_mutex); 104 ret = nfs_file_fsync_commit(file, start, end, datasync); 105 if (!ret && !datasync) 106 /* application has asked for meta-data sync */ 107 ret = pnfs_layoutcommit_inode(inode, true); 108 mutex_unlock(&inode->i_mutex); 109 /* 110 * If nfs_file_fsync_commit detected a server reboot, then 111 * resend all dirty pages that might have been covered by 112 * the NFS_CONTEXT_RESEND_WRITES flag 113 */ 114 start = 0; 115 end = LLONG_MAX; 116 } while (ret == -EAGAIN); 117 118 return ret; 119 } 120 121 const struct file_operations nfs4_file_operations = { 122 .llseek = nfs_file_llseek, 123 .read = do_sync_read, 124 .write = do_sync_write, 125 .aio_read = nfs_file_read, 126 .aio_write = nfs_file_write, 127 .mmap = nfs_file_mmap, 128 .open = nfs4_file_open, 129 .flush = nfs_file_flush, 130 .release = nfs_file_release, 131 .fsync = nfs4_file_fsync, 132 .lock = nfs_lock, 133 .flock = nfs_flock, 134 .splice_read = nfs_file_splice_read, 135 .splice_write = nfs_file_splice_write, 136 .check_flags = nfs_check_flags, 137 .setlease = nfs_setlease, 138 }; 139