Certain implementations of Inode::directory_entry_count were calling
functions which returned errors, but had no way of surfacing them.
Switch the return type to KResultOr<size_t> and start observing these
error paths.
Allow passing in an optional timeout to Thread::block and move
the timeout check out of Thread::Blocker. This way all Blockers
implicitly support timeouts and don't need to implement it
themselves. Do however allow them to override timeouts (e.g.
for sockets).
We need to have a Thread lock to protect threading related
operations, such as Thread::m_blocker which is used in
Thread::block.
Also, if a Thread::Blocker indicates that it should be
unblocking immediately, don't actually block the Thread
and instead return immediately in Thread::block.
By making the Process class RefCounted we don't really need
ProcessInspectionHandle anymore. This also fixes some race
conditions where a Process may be deleted while still being
used by ProcFS.
Also make sure to acquire the Process' lock when accessing
regions.
Last but not least, there's no reason why a thread can't be
scheduled while being inspected, though in practice it won't
happen anyway because the scheduler lock is held at the same
time.
To be more in line with other parts of Serenity's procfs, the
"key: value" format of /proc/cpuinfo was replaced with JSON, namely
an array of objects (one for each core).
The available keys remain the same, though "features" has been changed
from a space-separated string to an array of strings.
We now have BlockResult::WokeNormally and BlockResult::NotBlocked,
both of which indicate no error. We can no longer just check for
BlockResult::WokeNormally and assume anything else must be an
interruption.
We can now properly initialize all processors without
crashing by sending SMP IPI messages to synchronize memory
between processors.
We now initialize the APs once we have the scheduler running.
This is so that we can process IPI messages from the other
cores.
Also rework interrupt handling a bit so that it's more of a
1:1 mapping. We need to allocate non-sharable interrupts for
IPIs.
This also fixes the occasional hang/crash because all
CPUs now synchronize memory with each other.
FileBackedFileSystem is one that's backed by (mounted from) a file, in other
words one that has a "source" of the mount; that doesn't mean it deals in
blocks. The hierarchy now becomes:
* FS
* ProcFS
* DevPtsFS
* TmpFS
* FileBackedFS
* (future) Plan9FS
* BlockBasedFS
* Ext2FS
There isn't an easy way to retreive all register contents anymore,
so remove this functionality. We do have the ability to trace
processes, so it shouldn't really be needed anymore.
These APIs were clearly modeled after Ext2FS internals, and make perfect sense
in Ext2FS context. The new APIs are more generic, and map better to the
semantics exported to the userspace, where inode identifiers only appear in
stat() and readdir() output, but never in any input.
This will also hopefully reduce the potential for races (see commit c44b4d61f3).
Lastly, this makes it way more viable to implement a filesystem that only
synthesizes its inodes lazily when queried, and destroys them when they are no
longer in use. With inode identifiers being used to reference inodes, the only
choice for such a filesystem is to persist any inode it has given out the
identifier for, because it might be queried at any later time. With direct
references to inodes, the filesystem will know when the last reference is
dropped and the inode can be safely destroyed.
This fixes a bug where the mode of a FIFO was reported as 001000 instead
of 0010000 (you see the difference? me nethier), and hopefully doesn't
introduce new bugs. I've left 0777 and similar in a few places, because
that is *more* readable than its symbolic version.
Get rid of the weird old signature:
- int StringType::to_int(bool& ok) const
And replace it with sensible new signature:
- Optional<int> StringType::to_int() const
.. and make travis run it.
I renamed check-license-headers.sh to check-style.sh and expanded it so
that it now also checks for the presence of "#pragma once" in .h files.
It also checks the presence of a (single) blank line above and below the
"#pragma once" line.
I also added "#pragma once" to all the files that need it: even the ones
we are not check.
I also added/removed blank lines in order to make the script not fail.
I also ran clang-format on the files I modified.
This adds support for MS_RDONLY, a mount flag that tells the kernel to disallow
any attempts to write to the newly mounted filesystem. As this flag is
per-mount, and different mounts of the same filesystems (such as in case of bind
mounts) can have different mutability settings, you have to go though a custody
to find out if the filesystem is mounted read-only, instead of just asking the
filesystem itself whether it's inherently read-only.
This also adds a lot of checks we were previously missing; and moves some of
them to happen after more specific checks (such as regular permission checks).
One outstanding hole in this system is sys$mprotect(PROT_WRITE), as there's no
way we can know if the original file description this region has been mounted
from had been opened through a readonly mount point. Currently, we always allow
such sys$mprotect() calls to succeed, which effectively allows anyone to
circumvent the effect of MS_RDONLY. We should solve this one way or another.
VFS no longer deals with inodes in public API, only with custodies and file
descriptions. Talk directly to the file system if you need to operate on a
inode. In most cases you actually want to go though VFS, to get proper
permission check and other niceties. For this to work, you have to provide a
custody, which describes *how* you have opened the inode, not just what the
inode is.
We're going to make use of it in the next commit. But the idea is we want to
know how this File (more specifically, InodeFile) was opened in order to decide
how chown()/chmod() should behave, in particular whether it should be allowed or
not. Note that many other File operations, such as read(), write(), and ioctl(),
already require the caller to pass a FileDescription.
And move canonicalized_path() to a static method on LexicalPath.
This is to make it clear that FileSystemPath/canonicalized_path() only
perform *lexical* canonicalization.
Allow file system implementation to return meaningful error codes to
callers of the FileDescription::read_entire_file(). This allows both
Process::sys$readlink() and Process::sys$module_load() to return more
detailed errors to the user.
For singly-indirect blocks, "callback" is just "add_block".
For doubly-indirect blocks, "callback" is the lambda function
iterating on singly-indirect blocks: so instead of adding itself to the
list, the doubly-indirect block will add all its childs, but they add
themselves again when they run the callback of singly-indirect blocks.
And nothing adds the doubly-indirect block itself :(
This leads to a double free of all child blocks of the doubly-indirect
block, which is the failed assert described in #1549.
Closes: #1549.
read_block() and write_block() now accept the count (how many bytes to read
or write) and offset (where in the block to start; defaults to 0). Using these
new APIs, we can avoid doing copies between intermediary buffers in a lot more
cases. Hopefully this improves performance or something.
