refactor(memory): complete PMM/VMM/LMM rewrite - bitmap allocators, bug fixes, hardening

PMM Rewrite:
- Replace ~8KB record array with compact bitmaps
  (PhysPresent/PhysAlloc/PhysScanned, 128B each)
- Add PhysOwner[0..1023] for per-block ownership tracking
- new_block: O(1) amortised via NextFreeHint + dword-level BSF scan,
  returns 0 as OOM sentinel
- free_block: O(1) direct bit clear with double-free detection
- alloc_block: validates PhysPresent and PhysAlloc bits before allocation
- Add pmm_free_blocks/pmm_total_blocks stats functions

VMM Correctness Fixes:
- Fix free_page block extraction (Address SHR 10, was using
  raw Address field)
- Fix invlpg operand (use virtual address, was passing PDE index)
- Clear PDE entry on free_page before returning block to PMM
- Remove map_page double-write (delegate to map_page_ex only)
- Add OOM propagation (new_page returns false if PMM returns 0)
- Fix missing pop_trace in new_page error path

LMM Rewrite:
- Replace per-entry record array with bitmap allocator
  (93% vs 43% page efficiency)
- Layout: Header(24B) + Bitmap(64512B) + Padding + Data at 0x10000
- SIZE_PREFIX=16 for 16-byte aligned returns (SSE MOVAPS requirement)
- Next-fit bitmap scan with roving hint (NextFree) and dword-level
  fast skip
- Large alloc sentinel (LARGE_ALLOC_MAGIC=$FFFFFFFE) so kfree detects
  klalloc'd memory
- Implement klfree (was previously a no-op - pages could never
  be returned)
- Implement try_release_page (return fully-free heap pages to VMM/PMM)
- Fix interrupt safety: stack-balanced pushfd/cli/pop +
  restore_if (sti only)
  Fixes Bad TSS caused by popfd restoring dangerous EFLAGS bits (NT, IOPL)
- Zero memory via rep stosd instead of byte-by-byte loop

Hardening:
- kalloc OOM now triggers BSOD instead of returning nil
  (90% of callers don't check)
- Double-free detection in kfree (verify bitmap bits set before clearing)
- Guard bytes ({$IFDEF DEBUG_LMM}): $DEADBEEF sentinel for buffer overrun detection
- kpalloc: bounds check (block >= 1024 -> GPF) + syslog MMIO mapping audit log

Observability:
- Add MEMINFO command as src/prog/meminfo.pas (moved from inline kernel.pas)
- Displays multiboot memory, PMM block stats, LMM heap stats
- Register via progmanager.pas following standard prog pattern

Files changed:
- src/pmemorymanager.pas
- src/vmemorymanager.pas
- src/lmemorymanager.pas
- src/kernel.pas
- src/progmanager.pas
- src/prog/meminfo.pas

.drone.yml

@@ -22,8 +22,8 @@ steps:
     commands:
       - git fetch --tags
       - find . -type f -print0 | xargs -0 dos2unix
-      - chmod +x /drone/src/toolchain/*.sh
-      - /drone/src/toolchain/compile.sh
+      - chmod +x /drone/src/*.sh
+      - /drone/src/compile.sh
       
   - name: upload-iso-artifact
     image: alpine/git

.gitignore

@@ -14,8 +14,5 @@ localenv.json
 /lvgl/
 dockerout.txt
 AGENTS.md
-lessons_learnt.md
 *.log
 /doc/*.md
-wasuro
-src/core/core.version.pas

Dockerfile

@@ -14,9 +14,10 @@ RUN curl -sL https://sourceforge.net/projects/freepascal/files/Linux/$FPC_VERSIO
 	pushd fpc-$FPC_VERSION.i386-linux && ./install.sh && popd && \
 	rm -rf fpc-$FPC_VERSION.i386-linux
 
+COPY compile.sh /compile.sh
 ADD https://raw.githubusercontent.com/fsaintjacques/semver-tool/master/src/semver /usr/bin/semver
 RUN chmod +x /usr/bin/semver
 WORKDIR /code
 RUN find . -type f -print0 | xargs -0 dos2unix
 ENTRYPOINT ["/bin/bash", "-c"]
-CMD ["find toolchain -name '*.sh' -exec dos2unix {} + 2>/dev/null; find toolchain -name '*.sh' -exec chmod +x {} +; bash toolchain/compile.sh"]
+CMD ["/compile.sh"]

compat/lmemorymanager.pas

@@ -1,75 +0,0 @@
-{ Compatibility shim: wasuro references the old unit name 'lmemorymanager'.
-  Since wasuro/ cannot be modified, this unit re-exports the public API of
-  memory.heap so that 'uses lmemorymanager' continues to compile. }
-unit lmemorymanager;
-
-interface
-
-uses
-    memory.heap;
-
-const
-    ALLOC_UNIT        = memory.heap.ALLOC_UNIT;
-    DATA_OFFSET       = memory.heap.DATA_OFFSET;
-    PAGE_SIZE_LMM     = memory.heap.PAGE_SIZE_LMM;
-    TOTAL_UNITS       = memory.heap.TOTAL_UNITS;
-    BITMAP_DWORDS     = memory.heap.BITMAP_DWORDS;
-    SIZE_PREFIX       = memory.heap.SIZE_PREFIX;
-    LARGE_ALLOC_MAGIC = memory.heap.LARGE_ALLOC_MAGIC;
-
-type
-    PHeapPageHeader = memory.heap.PHeapPageHeader;
-    THeapPageHeader = memory.heap.THeapPageHeader;
-
-procedure init;
-function kalloc(size : uint32) : void;
-function klalloc(size : uint32) : void;
-procedure klfree(address : uint32);
-function kpalloc(address : uint32) : void;
-procedure kfree(area : void);
-function lmm_total_free : uint32;
-function lmm_page_count : uint32;
-
-implementation
-
-procedure init;
-begin
-    memory.heap.init;
-end;
-
-function kalloc(size : uint32) : void; inline;
-begin
-    kalloc := memory.heap.kalloc(size);
-end;
-
-function klalloc(size : uint32) : void; inline;
-begin
-    klalloc := memory.heap.klalloc(size);
-end;
-
-procedure klfree(address : uint32); inline;
-begin
-    memory.heap.klfree(address);
-end;
-
-function kpalloc(address : uint32) : void; inline;
-begin
-    kpalloc := memory.heap.kpalloc(address);
-end;
-
-procedure kfree(area : void); inline;
-begin
-    memory.heap.kfree(area);
-end;
-
-function lmm_total_free : uint32; inline;
-begin
-    lmm_total_free := memory.heap.lmm_total_free;
-end;
-
-function lmm_page_count : uint32; inline;
-begin
-    lmm_page_count := memory.heap.lmm_page_count;
-end;
-
-end.

compat/types.pas

@@ -1,7 +0,0 @@
-unit types;
-
-interface
-
-implementation
-
-end.

compile.sh

@@ -20,13 +20,10 @@ runOrFail() {
 	fi
 }
 
-TOOLCHAIN_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-
 declare -a run_steps=(
 	"compile_stub.sh" "Failed to compile stub!"
 	"compile_vergen.sh" "Versions failed to compile"
 	"compile_lvgl.sh" "Failed to compile LVGL!"
-	"compile_wasuro.sh" "Failed to pull Wasuro!"
 	"compile_sources.sh" "Failed to compile FPC Sources!"
 	"compile_link.sh" "Failed linking!"
 	"compile_isogen.sh" "Failed to create ISO!"
@@ -36,7 +33,7 @@ for ((i=0; i<${#run_steps[@]}; i+=2))
 do
 	if [ "$ERRCOUNT" -eq "0" ]
 	then
-			script="${TOOLCHAIN_DIR}/${run_steps[$i]}"
+			script=$(pwd)/"${run_steps[$i]}"
 			message="${run_steps[$i+1]}"
 			runOrFail "$script" "$message"
 	fi
@@ -45,9 +42,9 @@ done
 #Call generate final artifacts based on failure or success of the above.
 if [ "$ERRCOUNT" -ne "0" ]
 then
-	. "${TOOLCHAIN_DIR}/compile_finish.sh" "failed"
+	. ./compile_finish.sh "failed"
 else
-	. "${TOOLCHAIN_DIR}/compile_finish.sh" "success"
+	. ./compile_finish.sh "success"
 fi
 
 cd ..

compile_link.sh

@@ -19,4 +19,4 @@ echo " "
 LIBGCC=$(gcc -m32 -print-libgcc-file-name)
 echo "libgcc: ${LIBGCC}"
 
-ld -m elf_i386 -s --gc-sections -Ttoolchain/linker.script -o bin/kernel.bin $objstring --start-group lib/liblvgl.a ${LIBGCC} --end-group
+ld -m elf_i386 -s --gc-sections -Tlinker.script -o bin/kernel.bin $objstring --start-group lib/liblvgl.a ${LIBGCC} --end-group

compile_lvgl.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # compile_lvgl.sh — Download LVGL v9.2 source and compile into lib/liblvgl.a
 # Clone & compile in /tmp (fast container-local fs).
-# Cache liblvgl.a on host mount (/code/lvgl/) to skip rebuild.
+# Copy source + objects to /lvgl (host mount) for debugging.
 set -e
 
 LVGL_VERSION="v9.2.2"
@@ -10,7 +10,6 @@ LVGL_DIR="/tmp/lvgl"
 OBJ_DIR="/tmp/lvgl_obj"
 CONF_DIR="$(pwd)/lvglh"
 OUT_DIR="$(pwd)/lib"
-CACHE_DIR="/code/lvgl"
 
 CC="gcc"
 CFLAGS="-m32 -march=i686 -ffreestanding \
@@ -27,17 +26,6 @@ echo " "
 echo "Compiling LVGL..."
 echo " "
 
-# If cached liblvgl.a exists on host mount, just copy it and skip everything
-if [ -f "${CACHE_DIR}/liblvgl.a" ]; then
-    echo "Found cached liblvgl.a in ${CACHE_DIR}, copying to ${OUT_DIR}..."
-    cp "${CACHE_DIR}/liblvgl.a" "${OUT_DIR}/liblvgl.a"
-    echo "(Delete lvgl/liblvgl.a to force a full rebuild.)"
-    echo " "
-    echo "LVGL compilation complete (cached)."
-    echo " "
-    exit 0
-fi
-
 # Clone LVGL into /tmp (container-local)
 rm -rf "$LVGL_DIR"
 echo "Downloading LVGL ${LVGL_VERSION}..."
@@ -117,14 +105,12 @@ else
     echo "No custom LVGL files in lvglh/."
 fi
 
-# Cache liblvgl.a and source to host mount for next build
-echo "Caching LVGL to host mount..."
-mkdir -p "$CACHE_DIR"
-rm -rf ${CACHE_DIR}/* ${CACHE_DIR}/.[!.]* ${CACHE_DIR}/..?* 2>/dev/null || true
-cp "${OUT_DIR}/liblvgl.a" "${CACHE_DIR}/liblvgl.a"
-cp -a "$LVGL_DIR/src" "${CACHE_DIR}/src"
-cp -a "$LVGL_DIR"/*.h "${CACHE_DIR}/" 2>/dev/null || true
-cp -a "$OBJ_DIR" "${CACHE_DIR}/obj"
+# Copy source + objects to /lvgl host mount for debugging
+echo "Copying LVGL source and objects to host mount..."
+mkdir /code/lvgl 2>/dev/null || true
+rm -rf /code/lvgl/* /code/lvgl/.[!.]* /code/lvgl/..?* 2>/dev/null || true
+cp -a "$LVGL_DIR/src" /code/lvgl/src
+cp -a "$OBJ_DIR" /code/lvgl/obj
 echo "Done."
 
 echo " "

compile_sources.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+echo " "
+echo "======================="
+echo " "
+echo "Compiling FPC Sources..."
+echo " "
+fpc -Aelf -gw -g -gl -n -v0ew -O3 -OpPENTIUM3 -Si -Sc -Sg -Xd -CX -XXs -CfSSE -CfSSE2 -Rintel -Pi386 -Tlinux -FElib/ -Fusrc/* -Fusrc/driver/* -Fusrc/driver/net/* -Fusrc/driver/bus/* -Fusrc/driver/bus/usb/* -Fusrc/driver/hid/* src/kernel.pas

compile_stub.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+echo " "
+echo "======================="
+echo " "
+echo "Compiling Stub..."
+echo " "
+nasm -f elf src/stub/stub.asm -o lib/stub.o

compile_vergen.sh

@@ -1,15 +1,14 @@
 #!/usr/bin/env bash
 set -e
-TOOLCHAIN_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 echo " "
 echo "======================="
 echo " "
 echo "Generating Versioning Info..."
 echo " "
-chmod +x "${TOOLCHAIN_DIR}/compile_checksum.sh"
-"${TOOLCHAIN_DIR}/compile_checksum.sh"
-outfile="src/core/core.version.pas"
-file="toolchain/version"
+chmod +x ./compile_checksum.sh
+./compile_checksum.sh
+outfile="src/include/asuro.pas"
+file="version"
 {
 	# this script requires semver tool
 	wget -q https://raw.githubusercontent.com/fsaintjacques/semver-tool/master/src/semver -O bin/semver && chmod +x bin/semver
@@ -23,7 +22,7 @@ sub=$(semver get patch $tagref)
 version=$(semver get release $tagref)
 release=$(semver get prerel $tagref)
 build=$(semver get build $tagref)
-linecount=$("${TOOLCHAIN_DIR}/loc.sh" | awk '{print $1}')
+linecount=$(./loc.sh | awk '{print $1}')
 sourcecount=$(find src -type f | wc -l)
 drivercount=$(find src/driver -type f | wc -l)
 fpcversion=$(fpc -h | grep -m 1 version | awk '{print $5}')
@@ -35,7 +34,7 @@ checksum=$(md5sum checksums.md5 | awk '{print $1}')
 
 [[ -n "$release" ]] && version="$version-$release"
 cat > $outfile <<EOF
-unit core.version;
+unit asuro;
  
 interface
  

doc/flatfs.md

@@ -1,32 +0,0 @@
-#Flat filesystem
-
-A super simple filesystem for asuro. Folders are emulated in filenames.
-
-Starts with disk info sector, sector 0 of volume
-
----
-#### disk info
-
-jmp2boot        : ubit24;
-OEMName         : array[0..7] of char;
-version         : uint16 // numerical version of filesystem
-sectorCount      : uint16;
-fileCount       : uint16
-signature       : uint32 = 0x0B00B1E5
-
-
-the Rest of the sector is reserved
-
----
-
-Starting from sector 1 is the file table. Table size is determined by entry size (64) * fileCount
-
----
-####File entry
-
-name : array[0..59] of char //file name max 60 chars
-fileStart : 16bit // start sector of data
-fileSize : 16bit // data size in sectors
-
----
-