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naming: shm → shared_memory — 'shm' is a Unix clipping, not an acronym

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Per docs/coding-standards.md (no Unix-abbreviation exception): syscalls
shared_memory_create/map/physical, kernel SharedMemoryObject + handlers,
runtime.shared_memory (library/runtime/shared-memory.zig), the
shared-memory-server/-client test services, the shared-memory QEMU case,
and docs incl. vdso.md's danos_shared_memory_*. 87/87 QEMU tests pass.
This commit is contained in:
Daniel Samson
2026-07-21 17:26:15 +01:00
parent ec6e888076
commit 0045fd87ba
23 changed files with 192 additions and 192 deletions
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docs/display-v2.md
+5 -5
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@@ -1,7 +1,7 @@
# The display service v2: a pluggable scanout backend
**Status: complete (V1–V6).** The compositor boots on the GOP framebuffer and, when a
virtio-gpu driver announces itself, hot-attaches a native backend over the shared `shm`
virtio-gpu driver announces itself, hot-attaches a native backend over the shared-memory
scanout surface — with runtime mode-setting, EDID, and fenced presents, and it
re-attaches across driver restarts. All serial-gated (see [display-v2-plan.md](display-v2-plan.md)).
@@ -77,9 +77,9 @@ deferred (docs/display.md, "What v1 does not do"). v2 builds it: the natural gen
of M13 capability-passing from *endpoints* to *memory objects* —
```
shm_create(len) -> {handle, virtual_address} // a shareable, page-aligned RAM region
shared_memory_create(len) -> {handle, virtual_address} // a shareable, page-aligned RAM region
… pass `handle` as the send_cap on an ipc_call …
shm_map(cap) -> virtual_address // the receiver maps the same physical pages
shared_memory_map(cap) -> virtual_address // the receiver maps the same physical pages
```
The payoff is leverage: the **same** primitive unlocks **both** native GPU drivers *and*
@@ -92,7 +92,7 @@ A new ring-3 driver process (the topology v1 anticipated — "split the driver f
compositor when a second backend arrives"). It claims the virtio-gpu PCI function, and:
- sets up the **virtqueues** (control + cursor) and the device's config space,
- creates a **2D scanout resource** backed by an `shm` region, `attach_backing`s it,
- creates a **2D scanout resource** backed by a shared-memory region, `attach_backing`s it,
`set_scanout`s it to a CRTC, and `resource_flush`es damaged rectangles,
- reads **EDID** (the `GET_EDID` control command) for the mode list, and `set_scanout`
at a chosen mode for **runtime mode-setting**,
@@ -128,7 +128,7 @@ path in VMs**, where danos development happens. The framebuffer floor never goes
re-attach across driver restarts; GOP is the floor for "no driver ever," not a live
fall-back after a reprogram.
- **Detection = push** (the driver announces to `.display`), not compositor polling.
- **v2 builds the `shm` capability** (endpoints → memory objects), shared with the future
- **v2 builds the shared-memory capability** (endpoints → memory objects), shared with the future
client-surface path.
## See also