fs/nfs/nfs4file.c

   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 "pnfs.h"
   9
  10 #define NFSDBG_FACILITY         NFSDBG_FILE
  11
  12 static int
  13 nfs4_file_open(struct inode *inode, struct file *filp)
  14 {
  15         struct nfs_open_context *ctx;
  16         struct dentry *dentry = filp->f_path.dentry;
  17         struct dentry *parent = NULL;
  18         struct inode *dir;
  19         unsigned openflags = filp->f_flags;
  20         struct iattr attr;
  21         int err;
  22
  23         BUG_ON(inode != dentry->d_inode);
  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         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->f_path.dentry->d_inode;
  97
  98         ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
  99         if (ret != 0)
 100                 goto out;
 101         mutex_lock(&inode->i_mutex);
 102         ret = nfs_file_fsync_commit(file, start, end, datasync);
 103         if (!ret && !datasync)
 104                 /* application has asked for meta-data sync */
 105                 ret = pnfs_layoutcommit_inode(inode, true);
 106         mutex_unlock(&inode->i_mutex);
 107 out:
 108         return ret;
 109 }
 110
 111 const struct file_operations nfs4_file_operations = {
 112         .llseek         = nfs_file_llseek,
 113         .read           = do_sync_read,
 114         .write          = do_sync_write,
 115         .aio_read       = nfs_file_read,
 116         .aio_write      = nfs_file_write,
 117         .mmap           = nfs_file_mmap,
 118         .open           = nfs4_file_open,
 119         .flush          = nfs_file_flush,
 120         .release        = nfs_file_release,
 121         .fsync          = nfs4_file_fsync,
 122         .lock           = nfs_lock,
 123         .flock          = nfs_flock,
 124         .splice_read    = nfs_file_splice_read,
 125         .splice_write   = nfs_file_splice_write,
 126         .check_flags    = nfs_check_flags,
 127         .setlease       = nfs_setlease,
 128 };