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 if (inode != dentry->d_inode) 73 goto out_drop; 74 75 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 76 nfs_file_set_open_context(filp, ctx); 77 nfs_fscache_set_inode_cookie(inode, filp); 78 err = 0; 79 80 out_put_ctx: 81 put_nfs_open_context(ctx); 82 out: 83 dput(parent); 84 return err; 85 86 out_drop: 87 d_drop(dentry); 88 err = -EOPENSTALE; 89 goto out_put_ctx; 90 } 91 92 static int 93 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 94 { 95 int ret; 96 struct inode *inode = file_inode(file); 97 98 do { 99 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 100 if (ret != 0) 101 break; 102 mutex_lock(&inode->i_mutex); 103 ret = nfs_file_fsync_commit(file, start, end, datasync); 104 if (!ret && !datasync) 105 /* application has asked for meta-data sync */ 106 ret = pnfs_layoutcommit_inode(inode, true); 107 mutex_unlock(&inode->i_mutex); 108 /* 109 * If nfs_file_fsync_commit detected a server reboot, then 110 * resend all dirty pages that might have been covered by 111 * the NFS_CONTEXT_RESEND_WRITES flag 112 */ 113 start = 0; 114 end = LLONG_MAX; 115 } while (ret == -EAGAIN); 116 117 return ret; 118 } 119 120 const struct file_operations nfs4_file_operations = { 121 .llseek = nfs_file_llseek, 122 .read = do_sync_read, 123 .write = do_sync_write, 124 .aio_read = nfs_file_read, 125 .aio_write = nfs_file_write, 126 .mmap = nfs_file_mmap, 127 .open = nfs4_file_open, 128 .flush = nfs_file_flush, 129 .release = nfs_file_release, 130 .fsync = nfs4_file_fsync, 131 .lock = nfs_lock, 132 .flock = nfs_flock, 133 .splice_read = nfs_file_splice_read, 134 .splice_write = nfs_file_splice_write, 135 .check_flags = nfs_check_flags, 136 .setlease = nfs_setlease, 137 }; 138