1 /* 2 * linux/fs/nfs/file.c 3 * 4 * Copyright (C) 1992 Rick Sladkey 5 */ 6 #include <linux/fs.h> 7 #include <linux/falloc.h> 8 #include <linux/nfs_fs.h> 9 #include "internal.h" 10 #include "fscache.h" 11 #include "pnfs.h" 12 13 #include "nfstrace.h" 14 15 #ifdef CONFIG_NFS_V4_2 16 #include "nfs42.h" 17 #endif 18 19 #define NFSDBG_FACILITY NFSDBG_FILE 20 21 static int 22 nfs4_file_open(struct inode *inode, struct file *filp) 23 { 24 struct nfs_open_context *ctx; 25 struct dentry *dentry = filp->f_path.dentry; 26 struct dentry *parent = NULL; 27 struct inode *dir; 28 unsigned openflags = filp->f_flags; 29 struct iattr attr; 30 int opened = 0; 31 int err; 32 33 /* 34 * If no cached dentry exists or if it's negative, NFSv4 handled the 35 * opens in ->lookup() or ->create(). 36 * 37 * We only get this far for a cached positive dentry. We skipped 38 * revalidation, so handle it here by dropping the dentry and returning 39 * -EOPENSTALE. The VFS will retry the lookup/create/open. 40 */ 41 42 dprintk("NFS: open file(%pd2)\n", dentry); 43 44 if ((openflags & O_ACCMODE) == 3) 45 openflags--; 46 47 /* We can't create new files here */ 48 openflags &= ~(O_CREAT|O_EXCL); 49 50 parent = dget_parent(dentry); 51 dir = d_inode(parent); 52 53 ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); 54 err = PTR_ERR(ctx); 55 if (IS_ERR(ctx)) 56 goto out; 57 58 attr.ia_valid = ATTR_OPEN; 59 if (openflags & O_TRUNC) { 60 attr.ia_valid |= ATTR_SIZE; 61 attr.ia_size = 0; 62 nfs_sync_inode(inode); 63 } 64 65 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, &opened); 66 if (IS_ERR(inode)) { 67 err = PTR_ERR(inode); 68 switch (err) { 69 case -EPERM: 70 case -EACCES: 71 case -EDQUOT: 72 case -ENOSPC: 73 case -EROFS: 74 goto out_put_ctx; 75 default: 76 goto out_drop; 77 } 78 } 79 if (inode != d_inode(dentry)) 80 goto out_drop; 81 82 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 83 nfs_file_set_open_context(filp, ctx); 84 nfs_fscache_open_file(inode, filp); 85 err = 0; 86 87 out_put_ctx: 88 put_nfs_open_context(ctx); 89 out: 90 dput(parent); 91 return err; 92 93 out_drop: 94 d_drop(dentry); 95 err = -EOPENSTALE; 96 goto out_put_ctx; 97 } 98 99 static int 100 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 101 { 102 int ret; 103 struct inode *inode = file_inode(file); 104 105 trace_nfs_fsync_enter(inode); 106 107 nfs_inode_dio_wait(inode); 108 do { 109 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 110 if (ret != 0) 111 break; 112 mutex_lock(&inode->i_mutex); 113 ret = nfs_file_fsync_commit(file, start, end, datasync); 114 if (!ret) 115 ret = pnfs_sync_inode(inode, !!datasync); 116 mutex_unlock(&inode->i_mutex); 117 /* 118 * If nfs_file_fsync_commit detected a server reboot, then 119 * resend all dirty pages that might have been covered by 120 * the NFS_CONTEXT_RESEND_WRITES flag 121 */ 122 start = 0; 123 end = LLONG_MAX; 124 } while (ret == -EAGAIN); 125 126 trace_nfs_fsync_exit(inode, ret); 127 return ret; 128 } 129 130 #ifdef CONFIG_NFS_V4_2 131 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 132 { 133 loff_t ret; 134 135 switch (whence) { 136 case SEEK_HOLE: 137 case SEEK_DATA: 138 ret = nfs42_proc_llseek(filep, offset, whence); 139 if (ret != -ENOTSUPP) 140 return ret; 141 default: 142 return nfs_file_llseek(filep, offset, whence); 143 } 144 } 145 146 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 147 { 148 struct inode *inode = file_inode(filep); 149 long ret; 150 151 if (!S_ISREG(inode->i_mode)) 152 return -EOPNOTSUPP; 153 154 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 155 return -EOPNOTSUPP; 156 157 ret = inode_newsize_ok(inode, offset + len); 158 if (ret < 0) 159 return ret; 160 161 if (mode & FALLOC_FL_PUNCH_HOLE) 162 return nfs42_proc_deallocate(filep, offset, len); 163 return nfs42_proc_allocate(filep, offset, len); 164 } 165 #endif /* CONFIG_NFS_V4_2 */ 166 167 const struct file_operations nfs4_file_operations = { 168 #ifdef CONFIG_NFS_V4_2 169 .llseek = nfs4_file_llseek, 170 #else 171 .llseek = nfs_file_llseek, 172 #endif 173 .read_iter = nfs_file_read, 174 .write_iter = nfs_file_write, 175 .mmap = nfs_file_mmap, 176 .open = nfs4_file_open, 177 .flush = nfs_file_flush, 178 .release = nfs_file_release, 179 .fsync = nfs4_file_fsync, 180 .lock = nfs_lock, 181 .flock = nfs_flock, 182 .splice_read = nfs_file_splice_read, 183 .splice_write = iter_file_splice_write, 184 #ifdef CONFIG_NFS_V4_2 185 .fallocate = nfs42_fallocate, 186 #endif /* CONFIG_NFS_V4_2 */ 187 .check_flags = nfs_check_flags, 188 .setlease = simple_nosetlease, 189 }; 190