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 err = nfs_check_flags(openflags); 45 if (err) 46 return err; 47 48 if ((openflags & O_ACCMODE) == 3) 49 openflags--; 50 51 /* We can't create new files here */ 52 openflags &= ~(O_CREAT|O_EXCL); 53 54 parent = dget_parent(dentry); 55 dir = d_inode(parent); 56 57 ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); 58 err = PTR_ERR(ctx); 59 if (IS_ERR(ctx)) 60 goto out; 61 62 attr.ia_valid = ATTR_OPEN; 63 if (openflags & O_TRUNC) { 64 attr.ia_valid |= ATTR_SIZE; 65 attr.ia_size = 0; 66 nfs_sync_inode(inode); 67 } 68 69 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, &opened); 70 if (IS_ERR(inode)) { 71 err = PTR_ERR(inode); 72 switch (err) { 73 case -EPERM: 74 case -EACCES: 75 case -EDQUOT: 76 case -ENOSPC: 77 case -EROFS: 78 goto out_put_ctx; 79 default: 80 goto out_drop; 81 } 82 } 83 if (inode != d_inode(dentry)) 84 goto out_drop; 85 86 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 87 nfs_file_set_open_context(filp, ctx); 88 nfs_fscache_open_file(inode, filp); 89 err = 0; 90 91 out_put_ctx: 92 put_nfs_open_context(ctx); 93 out: 94 dput(parent); 95 return err; 96 97 out_drop: 98 d_drop(dentry); 99 err = -EOPENSTALE; 100 goto out_put_ctx; 101 } 102 103 static int 104 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 105 { 106 int ret; 107 struct inode *inode = file_inode(file); 108 109 trace_nfs_fsync_enter(inode); 110 111 nfs_inode_dio_wait(inode); 112 do { 113 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 114 if (ret != 0) 115 break; 116 mutex_lock(&inode->i_mutex); 117 ret = nfs_file_fsync_commit(file, start, end, datasync); 118 if (!ret) 119 ret = pnfs_sync_inode(inode, !!datasync); 120 mutex_unlock(&inode->i_mutex); 121 /* 122 * If nfs_file_fsync_commit detected a server reboot, then 123 * resend all dirty pages that might have been covered by 124 * the NFS_CONTEXT_RESEND_WRITES flag 125 */ 126 start = 0; 127 end = LLONG_MAX; 128 } while (ret == -EAGAIN); 129 130 trace_nfs_fsync_exit(inode, ret); 131 return ret; 132 } 133 134 #ifdef CONFIG_NFS_V4_2 135 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 136 { 137 loff_t ret; 138 139 switch (whence) { 140 case SEEK_HOLE: 141 case SEEK_DATA: 142 ret = nfs42_proc_llseek(filep, offset, whence); 143 if (ret != -ENOTSUPP) 144 return ret; 145 default: 146 return nfs_file_llseek(filep, offset, whence); 147 } 148 } 149 150 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 151 { 152 struct inode *inode = file_inode(filep); 153 long ret; 154 155 if (!S_ISREG(inode->i_mode)) 156 return -EOPNOTSUPP; 157 158 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 159 return -EOPNOTSUPP; 160 161 ret = inode_newsize_ok(inode, offset + len); 162 if (ret < 0) 163 return ret; 164 165 if (mode & FALLOC_FL_PUNCH_HOLE) 166 return nfs42_proc_deallocate(filep, offset, len); 167 return nfs42_proc_allocate(filep, offset, len); 168 } 169 #endif /* CONFIG_NFS_V4_2 */ 170 171 const struct file_operations nfs4_file_operations = { 172 #ifdef CONFIG_NFS_V4_2 173 .llseek = nfs4_file_llseek, 174 #else 175 .llseek = nfs_file_llseek, 176 #endif 177 .read_iter = nfs_file_read, 178 .write_iter = nfs_file_write, 179 .mmap = nfs_file_mmap, 180 .open = nfs4_file_open, 181 .flush = nfs_file_flush, 182 .release = nfs_file_release, 183 .fsync = nfs4_file_fsync, 184 .lock = nfs_lock, 185 .flock = nfs_flock, 186 .splice_read = nfs_file_splice_read, 187 .splice_write = iter_file_splice_write, 188 #ifdef CONFIG_NFS_V4_2 189 .fallocate = nfs42_fallocate, 190 #endif /* CONFIG_NFS_V4_2 */ 191 .check_flags = nfs_check_flags, 192 .setlease = simple_nosetlease, 193 }; 194