We don't need an entirely separate VMObject subclass to influence the
location of the physical pages.
Instead, we simply allocate enough physically contiguous memory first,
and then pass it to the AnonymousVMObject constructor that takes a span
of physical pages.
Previously there was no way to create a MACAddress by passing a direct
address as a string. This will allow programs like the arp utility to
create a MACAddress instance by user-passed addresses.
VMObject already has an IntrusiveList of all the Regions that map it.
We were keeping a counter in addition to this, and only using it in
a single place to avoid iterating over the list in case it only had
1 entry.
Simplify VMObject by removing this counter and always iterating the
list even if there's only 1 entry. :^)
This was previously used for a single debug logging statement during
memory purging. There are no remaining users of this weak pointer,
so let's get rid of it.
If a purgeable VM object is in the "volatile" state when we're asked
to make a COW clone of it, make life simpler by simply "purging"
the cloned object right away.
This effectively means that a fork()'ed child process will discover
its purgeable+volatile regions to be empty if/when it tries making
them non-volatile.
This patch changes the semantics of purgeable memory.
- AnonymousVMObject now has a "purgeable" flag. It can only be set when
constructing the object. (Previously, all anonymous memory was
effectively purgeable.)
- AnonymousVMObject now has a "volatile" flag. It covers the entire
range of physical pages. (Previously, we tracked ranges of volatile
pages, effectively making it a page-level concept.)
- Non-volatile objects maintain a physical page reservation via the
committed pages mechanism, to ensure full coverage for page faults.
- When an object is made volatile, it relinquishes any unused committed
pages immediately. If later made non-volatile again, we then attempt
to make a new committed pages reservation. If this fails, we return
ENOMEM to userspace.
mmap() now creates purgeable objects if passed the MAP_PURGEABLE option
together with MAP_ANONYMOUS. anon_create() memory is always purgeable.
Instead of crashing when we can't make the back buffer non-volatile,
we now transition the window into single-buffered mode instead
(assuming it was originally in double-buffered mode.)
This reduces GUI fidelity a bit (by potentially making windows flicker
during repaint) but since it's only triggered in low-memory conditions,
it seems like a reasonable thing to sacrifice in order for the system
to carry on.
This patch also stops us from allocating entirely new backing stores
after the old ones were purged. If they were purged but reallocated
just fine, there's no need to allocate new memory again. We already
have fresh zero-filled pages in the existing bitmap at this point.
Making a bitmap non-volatile after being volatile may fail to allocate
physical pages after the kernel stole the old pages in a purge.
This is different from the pages being purged, but reallocated. In that
case, they are simply replaced with zero-fill-on-demand pages as if
they were freshly allocated.
This was a really weird thing to begin with, purgeable bitmaps were
basically regular bitmaps without a physical memory reservation.
Since all the clients of this code ended up populating the bitmaps
with pixels immediately after allocating them anyway, there was no
need to avoid the reservation.
Instead, all Gfx::Bitmaps are now purgeable, in the sense that they
can be marked as volatile or non-volatile.
The only difference here is that allocation failure is surfaced when
we try to create the bitmap instead of during the handling of a
subsequent page fault.
This prevents GUI::TextBox and the `Paste & Go` action in the browser
from trying to paste a bitmap. Also, the paste action is enabled
and disabled on clipboard change to reflect if the clipboard data
can be pasted.
In my case the mail server responded with the following after selecting
a mailbox (in the Mail application):
* OK [CLOSED] Previous mailbox closed.
* FLAGS (\Answered \Flagged ...)
* OK [PERMANENTFLAGS (\Answered \Flagged ... \*)] Flags permitted.
* 2 EXISTS
* 0 RECENT
* OK [UIDVALIDITY 1234567890] UIDs valid
* OK [UIDNEXT 12345] Predicted next UID
* OK [HIGHESTMODSEQ 123456] Highest
A6 OK [READ-WRITE] Select completed (0.002 secs).
The [CLOSED] part threw the parser off as it was expecting a space after
the atom following the opening bracket, which would actually lead to a
crash of Mail (AK::Optional::value() without value).
This patch adds the box-shadow rendering to Boxes. We do parse the
blur-radius of a box-shadow but we don't use it for now as the Filter
in the system don't seem quite powerful enough yet to handle that.
This adds support for box-shadows to the DeprecatedCSSParser. When it
encounters a box-shadow property, the following syntaxes can get parsed:
- box-shadow: <offset_x> <offset_y> <color>
- box-shadow: <offset_x> <offset_y> <blur_radius> <color>
There is other possible data following the property, but those aren't
supported for now.
This patch spreads box-shadows around:
- The Values important to box-shadows are stored in a BoxShadowData
struct
- StyleProperties knows how to construct such a struct from a
BoxShadowStyleValue and a Node knows how to ask for it
- CalculatedValues contain BoxShadowData and expose them
Right now, NE2000 NICs don't work because the link is down by default
and this will never change. Of all the NE2000 documentation I looked
at I could not find a link status indicator, so just assume the link
is up.
next_packet_page points to a page, but was being compared to a byte
offset rather than a page offset when adjusting the BOUNDARY register
when the ring buffer wraps around.
Fixes#8327.
The original work was done in #2752
(deceb91c48 to be precise),
but unfortunately 2c772d1848 replaced
on_selection with on_selection_change, which caused the function
to never be executed, as it was reassigned a few lines below.
For example, the servers I tested this on sent "Subject" which matched
what I was checking for. However, some servers can send "SUBJECT" which
didn't match and would cause an assertion failure.
