Signed-off-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

If iov->iov_len == 0, it will loop forever.
uiomove() will take care of the zero iov len case.

Signed-off-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

Changes since v2:
  - v1 dropped lock in vn_lookup, thus assert that vnode_lock is held.

Changes since v3:
  - Fix lock ordering issue in dentry_lookup. The lock respective to the parent
node must be acquired before dentry_lookup and released after the process is
done. Otherwise, a second thread looking up for the same dentry may take the
'NULL' path incorrectly.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

This patch fixes the error codes in four error cases:

1. unlink() of a directory used to return EPERM (as in Posix), and now
   returns EISDIR (as in Linux).

2. rmdir() of a non-empty directory used to return EEXIST (as in Posix)
   and now returns ENOTEMPTY (as in Linux).

3. rmdir() of a regular file (non-directory) used to return EBADF
   and now returns ENOTDIR (as in Linux).

4. readdir() of a regular file (non-directory) used to return EBADF
   and now returns ENOTDIR (as in Linux).

This patch also adds a test, tst-remove.cc, for the various unlink() and
rmdir() success and failure modes.

Fixes #123.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

I tried using a test which called mknod() (to create an empty regular file).
Despite us having an mknod() implementation, it didn't work, and failed on
lookup of the symbol __xmknod.

Turns out that in glibc, mknod() is source-only, and converted to the ABI
function which is __xmknod, whose first parameter is a version number
_MKNOD_VER_LINUX (0 on x86-64 Linux).

So this patch implements __xmknod, and now mknod() works.

Note we already had the same kind of trick for __xstat(), needed so that
stat() would work.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

main.cc was still using tab characters instead of spaces as our coding
conventions dictate. Reindent it, using Eclipse's ctrl-I.
This patch doesn't change anything else.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

This reverts commit e4aad1ba.

It causes tst-vfs.so to just hang.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

  - Drop lock in vn_lookup() and assert that vnode_lock is held.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Everyone is now overriding file's virtual functions; we can make them
pure virtual and remove fileops completely.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Unused.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Everyone switched to the nifty variadic type.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Derived file objects will be initialized by the class constructor, no need
for fo_init().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Once file::~file() is called, virtual functions no longer dispatch to the
derived type (which has since been destroyed) but to the base type, which
is uninteresting.

Move the call to close() from the destructor to fdrop().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

The default is to dispatch directly to the corresponding member of f_ops,
but that can be overridden.

The fo_*() functions are redirected to dispatch via the virtual functions.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Make sure ZFS intention log is flushed to disk by unmounting rootfs at
poweroff.

Fixes #108.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Make sure the new root vnode is not evicted in vflush() and that we
don't keep reference to the old root dentry in ->m_covered.

Fixes negative dentry count when pivoted root is unmounted.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Add sys_umount2() and implement support for MNT_FORCE that will be used
to force rootfs unmount at poweroff.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

This paves the way for moving f_ops into the vtable.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Simpler.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

'new file' doesn't return nullptr, it throws (well except in osv where new
always succeeds).

Replace with new (nothrow) to get the expected behaviour.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

They are called at the same time, so make falloc_noinstall() responsible
purely for allocation.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

If we're going to have a vtable in there, the memset() will kill it.

Instead, add initializers for those members not already initialized by
make_file().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

The only caller, soo_close() can only be called from a context where
no file references remain, so no further file API calls can be made.

Remove it.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Subsumed by make_file().

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Makes it easy to avoid losing them.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Combines falloc_noinstall() and finit(), which are always used together.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

falloc() is inherently racy in that it installs an uninitialized file
descriptor in a user accessible fd.  It is also hard to use correctly when
an error occurs.  Luckily, we don't use it anywhere, so we can just remove it.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Copying filerefs is expensive since the reference count is incremented,
avoid it.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently sys_open() receives an uninitialized file structure from its
callers, which is awkward as the callers must handle opening a file in
two steps.  It also doesn't fit well with C++'s notion of an object being
always fully initialized and valid.

Fix by making sys_open() allocate and return the file structure.  This also
fixes a window in open() where an fd would point to an uninitialized file
(between fdalloc() and sys_open()).

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Enable device_destroy() API for the virtio-rng driver.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Before this patch, OSv crashes or continuously reboots when given unknown
command line paramters, e.g.,

        scripts/run.py -c1 -e "--help --z a"

With this patch, it says, as expected that the "--z" option is not
recognized, and displays the list of known options:

    unrecognised option '--z'
    OSv options:
      --help                show help text
      --trace arg           tracepoints to enable
      --trace-backtrace     log backtraces in the tracepoint log
      --leak                start leak detector after boot
      --nomount             don't mount the file system
      --noshutdown          continue running after main() returns
      --env arg             set Unix-like environment variable (putenv())
      --cwd arg             set current working directory
    Aborted

The problem was that to parse the command line options, we used Boost,
which throws an exception when an unrecognized option is seen. We need
to catch this exception, and show a message accordingly.

But before this patch, C++ exceptions did not work correctly during this
stage of the boot process, because exceptions use elf::program(), and we
only set it up later. So this patch moves the setup of the elf::program()
object earlier in the boot, to the beginning of main_cont().

Now we'll be able to use C++ exceptions throughout main_cont(), not just
in command line parsing.

This patch also removes the unused "filesystem" paramter of
elf::program(), rather than move the initializion of this empty object
as well.

Fixes #103.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Needed for C++ conversion.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

In preparation for making 'file' a C++ type.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>