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 #ifdef CONFIG_NFS_V4_2 14 #include "nfs42.h" 15 #endif 16 17 #define NFSDBG_FACILITY NFSDBG_FILE 18 19 static int 20 nfs4_file_open(struct inode *inode, struct file *filp) 21 { 22 struct nfs_open_context *ctx; 23 struct dentry *dentry = filp->f_path.dentry; 24 struct dentry *parent = NULL; 25 struct inode *dir; 26 unsigned openflags = filp->f_flags; 27 struct iattr attr; 28 int opened = 0; 29 int err; 30 31 /* 32 * If no cached dentry exists or if it's negative, NFSv4 handled the 33 * opens in ->lookup() or ->create(). 34 * 35 * We only get this far for a cached positive dentry. We skipped 36 * revalidation, so handle it here by dropping the dentry and returning 37 * -EOPENSTALE. The VFS will retry the lookup/create/open. 38 */ 39 40 dprintk("NFS: open file(%pd2)\n", dentry); 41 42 if ((openflags & O_ACCMODE) == 3) 43 openflags--; 44 45 /* We can't create new files here */ 46 openflags &= ~(O_CREAT|O_EXCL); 47 48 parent = dget_parent(dentry); 49 dir = parent->d_inode; 50 51 ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); 52 err = PTR_ERR(ctx); 53 if (IS_ERR(ctx)) 54 goto out; 55 56 attr.ia_valid = ATTR_OPEN; 57 if (openflags & O_TRUNC) { 58 attr.ia_valid |= ATTR_SIZE; 59 attr.ia_size = 0; 60 nfs_wb_all(inode); 61 } 62 63 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, &opened); 64 if (IS_ERR(inode)) { 65 err = PTR_ERR(inode); 66 switch (err) { 67 case -EPERM: 68 case -EACCES: 69 case -EDQUOT: 70 case -ENOSPC: 71 case -EROFS: 72 goto out_put_ctx; 73 default: 74 goto out_drop; 75 } 76 } 77 if (inode != dentry->d_inode) 78 goto out_drop; 79 80 nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); 81 nfs_file_set_open_context(filp, ctx); 82 nfs_fscache_open_file(inode, filp); 83 err = 0; 84 85 out_put_ctx: 86 put_nfs_open_context(ctx); 87 out: 88 dput(parent); 89 return err; 90 91 out_drop: 92 d_drop(dentry); 93 err = -EOPENSTALE; 94 goto out_put_ctx; 95 } 96 97 static int 98 nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync) 99 { 100 int ret; 101 struct inode *inode = file_inode(file); 102 103 do { 104 ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 105 if (ret != 0) 106 break; 107 mutex_lock(&inode->i_mutex); 108 ret = nfs_file_fsync_commit(file, start, end, datasync); 109 if (!ret) 110 ret = pnfs_layoutcommit_inode(inode, true); 111 mutex_unlock(&inode->i_mutex); 112 /* 113 * If nfs_file_fsync_commit detected a server reboot, then 114 * resend all dirty pages that might have been covered by 115 * the NFS_CONTEXT_RESEND_WRITES flag 116 */ 117 start = 0; 118 end = LLONG_MAX; 119 } while (ret == -EAGAIN); 120 121 return ret; 122 } 123 124 #ifdef CONFIG_NFS_V4_2 125 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence) 126 { 127 loff_t ret; 128 129 switch (whence) { 130 case SEEK_HOLE: 131 case SEEK_DATA: 132 ret = nfs42_proc_llseek(filep, offset, whence); 133 if (ret != -ENOTSUPP) 134 return ret; 135 default: 136 return nfs_file_llseek(filep, offset, whence); 137 } 138 } 139 140 static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len) 141 { 142 struct inode *inode = file_inode(filep); 143 long ret; 144 145 if (!S_ISREG(inode->i_mode)) 146 return -EOPNOTSUPP; 147 148 if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE))) 149 return -EOPNOTSUPP; 150 151 ret = inode_newsize_ok(inode, offset + len); 152 if (ret < 0) 153 return ret; 154 155 mutex_lock(&inode->i_mutex); 156 if (mode & FALLOC_FL_PUNCH_HOLE) 157 ret = nfs42_proc_deallocate(filep, offset, len); 158 else 159 ret = nfs42_proc_allocate(filep, offset, len); 160 mutex_unlock(&inode->i_mutex); 161 162 nfs_zap_caches(inode); 163 return ret; 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