commit fce9655d96d3c4e85934ac6c6a9918adad0d4321 · pci.express/frostium

+13 -7

components/ukernel/arch/amd64/boot.zig

···

       9
       9
        
       const StandardGdt = arch.structures.gdt.StandardGdt;

     

       10
       10
        
       const Tss = arch.structures.tss.Tss;

     

       11
       11
        
       

     

       12
       12
       +
       var pg_ctx: arch.mm.paging.Context = undefined;

     

       13
       13
       +
       

     

       12
       14
        
       pub const limine_requests = struct {

     

       13
       15
        
           export var start_marker: limine.RequestsStartMarker linksection(".limine_reqs_start") = .{};

     

       14
       16
        
           export var end_marker: limine.RequestsEndMarker linksection(".limine_reqs_end") = .{};

     
···

       104
       106
        
       

     

       105
       107
        
           log.info("Setting up scheduling...", .{});

     

       106
       108
        
       

     

       109
       109
       +
           pg_ctx = arch.mm.paging.Context.get_current();

     

       110
       110
       +
       

     

       107
       111
        
           initApic() catch |err| {

     

       108
       112
        
               log.err("Failed to set up APIC! {}", .{err});

     

       109
       113
        
               @panic("apic");

     
···

       117
       121
        
               .size = 0x1000,

     

       118
       122
        
               .memory_type = .MemoryWriteBack,

     

       119
       123
        
               .perms = .{

     

       120
       120
       -
                   .executable = false,

     

       121
       121
       -
                   .userspace_accessible = true,

     

       122
       122
       -
                   .writable = true,

     

       124
       124
       +
                   .x = false,

     

       125
       125
       +
                   .u = true,

     

       126
       126
       +
                   .w = true,

     

       123
       127
        
               },

     

       128
       128
       +
               .context = &pg_ctx,

     

       124
       129
        
           }) catch @panic("couldn't map user stack");

     

       125
       130
        
       

     

       126
       126
       -
           const entry = common.loadRootTask() catch |err| {

     

       131
       131
       +
           const entry = common.loadRootTask(&pg_ctx) catch |err| {

     

       127
       132
        
               log.err("Couldn't load the root task! {}", .{err});

     

       128
       133
        
               @panic("ggz");

     

       129
       134
        
           };

     
···

       217
       222
        
                       .size = 0x1000,

     

       218
       223
        
                       .memory_type = .DeviceUncacheable,

     

       219
       224
        
                       .perms = .{

     

       220
       220
       -
                           .executable = false,

     

       221
       221
       -
                           .userspace_accessible = false,

     

       222
       222
       -
                           .writable = true,

     

       225
       225
       +
                           .x = false,

     

       226
       226
       +
                           .u = false,

     

       227
       227
       +
                           .w = true,

     

       223
       228
        
                       },

     

       229
       229
       +
                       .context = &pg_ctx,

     

       224
       230
        
                   });

     

       225
       231
        
                   break :blk .{ .xapic = apic_base };

     

       226
       232
        
               },

+207 -155

components/ukernel/arch/amd64/mm/paging.zig

···

       1
       1
       -
       const common = @import("common");

     

       2
       1
        
       const arch = @import("../root.zig");

     

       2
       2
       +
       const common = @import("common");

     

       3
       3
        
       const std = @import("std");

     

       4
       4
       -
       const physToVirt = common.mm.physToHHDM;

     

       4
       4
       +
       const Cr3 = arch.registers.ControlRegisters.Cr3;

     

       5
       5
       +
       const Cr4 = arch.registers.ControlRegisters.Cr4;

     

       5
       6
        
       const Perms = common.mm.paging.Perms;

     

       6
       6
       -
       

     

       7
       7
       -
       pub const page_sizes = [_]usize{

     

       8
       8
       -
           0x1000, // 4K

     

       9
       9
       -
           0x200000, // 2M

     

       10
       10
       -
           0x40000000, // 1G

     

       11
       11
       -
           0x8000000000, // 512G

     

       12
       12
       -
           0x1000000000000, // 256T

     

       13
       13
       -
       };

     

       14
       7
        
       

     

       15
       8
        
       pub const PageTable = extern struct {

     

       16
       9
        
           entries: [512]Entry,

     
···

       43
       36
        
           };

     

       44
       37
        
       };

     

       45
       38
        
       

     

       46
       46
       -
       fn extract_index_from_vaddr(vaddr: u64, level: u6) u9 {

     

       47
       47
       -
           const shamt = 12 + level * 9;

     

       48
       48
       -
           return @truncate(vaddr >> shamt);

     

       39
       39
       +
       pub const MemoryType = enum {

     

       40
       40
       +
           DeviceUncacheable,

     

       41
       41
       +
           DeviceWriteCombining,

     

       42
       42
       +
           MemoryWritethrough,

     

       43
       43
       +
           MemoryWriteBack,

     

       44
       44
       +
       };

     

       45
       45
       +
       

     

       46
       46
       +
       pub fn detect_5level() bool {

     

       47
       47
       +
           const bits: u64 = 1 << 12;

     

       48
       48
       +
           return Cr4.read() & bits != 0;

     

       49
       49
        
       }

     

       50
       50
        
       

     

       51
       51
       -
       pub const TypedPTE = union(common.mm.paging.PTEType) {

     

       52
       52
       -
           Mapping: MappingHandle,

     

       53
       53
       -
           Table: TableHandle,

     

       54
       54
       -
           Empty,

     

       51
       51
       +
       pub const Context = struct {

     

       52
       52
       +
           cr3_val: u64,

     

       53
       53
       +
           level5: bool,

     

       55
       54
        
       

     

       56
       55
        
           const Self = @This();

     

       56
       56
       +
           pub fn apply(self: *Self) void {

     

       57
       57
       +
               // NX Enable

     

       58
       58
       +
               const IA32_EFER = arch.registers.MSR(u64, 0xC0000080);

     

       59
       59
       +
               const efer_val = IA32_EFER.read() | (0b1 << 11);

     

       60
       60
       +
               IA32_EFER.write(efer_val);

     

       61
       61
       +
       

     

       62
       62
       +
               // Set the level 5 bit accordingly

     

       63
       63
       +
               const cr4 = Cr4.read();

     

       64
       64
       +
               const level5mask: u64 = 1 << 12;

     

       65
       65
       +
               Cr4.write(if (self.level5) cr4 | level5mask else cr4 & ~level5mask);

     

       66
       66
       +
       

     

       67
       67
       +
               Cr3.write(self.cr3_val);

     

       68
       68
       +
           }

     

       57
       69
        
       

     

       58
       58
       -
           pub fn decode(pte: *PageTable.Entry, level: u3) Self {

     

       70
       70
       +
           pub fn get_current() Context {

     

       71
       71
       +
               return .{

     

       72
       72
       +
                   .cr3_val = Cr3.read(),

     

       73
       73
       +
                   .level5 = detect_5level(),

     

       74
       74
       +
               };

     

       75
       75
       +
           }

     

       76
       76
       +
       

     

       77
       77
       +
           pub fn can_map_at(_: *const Self, level: u3) bool {

     

       78
       78
       +
               return level < 2;

     

       79
       79
       +
           }

     

       80
       80
       +
       

     

       81
       81
       +
           // We need the parameter because aarch64 has 2 root page tables

     

       82
       82
       +
           pub fn root_table(self: *Self, _: u64) TableHandle {

     

       83
       83
       +
               return .{

     

       84
       84
       +
                   .paddr = self.cr3_val,

     

       85
       85
       +
                   .level = if (self.level5) 5 else 4,

     

       86
       86
       +
                   .context = self,

     

       87
       87
       +
                   .perms = .{

     

       88
       88
       +
                       .x = true,

     

       89
       89
       +
                       .w = true,

     

       90
       90
       +
                       .u = true,

     

       91
       91
       +
                   },

     

       92
       92
       +
                   .underlying = null,

     

       93
       93
       +
               };

     

       94
       94
       +
           }

     

       95
       95
       +
       

     

       96
       96
       +
           pub fn decode(self: *Self, pte: *PageTable.Entry, level: u3) SomePteHandle {

     

       59
       97
        
               if (!pte.present) {

     

       60
       98
        
                   return .Empty;

     

       61
       99
        
               }

     

       62
       100
        
               if (!pte.huge and level != 0) {

     

       63
       63
       -
                   return .{ .Table = decode_table(pte, level) };

     

       101
       101
       +
                   return .{ .Table = self.parse_table(pte, level) };

     

       64
       102
        
               }

     

       65
       65
       -
               return .{ .Mapping = decode_mapping(pte, level) };

     

       103
       103
       +
               return .{ .Mapping = self.parse_mapping(pte, level) };

     

       66
       104
        
           }

     

       67
       105
        
       

     

       68
       68
       -
           pub fn decode_table(pte: *PageTable.Entry, level: u3) TableHandle {

     

       106
       106
       +
           pub fn parse_mapping(self: *Self, pte: *PageTable.Entry, level: u3) MappingHandle {

     

       107
       107
       +
               const memory_type = self.decode_memory_type(pte, level);

     

       69
       108
        
               return .{

     

       70
       70
       -
                   .phys_addr = pte.getAddr(),

     

       109
       109
       +
                   .context = self,

     

       110
       110
       +
                   .paddr = pte.getAddr(),

     

       71
       111
        
                   .level = level,

     

       112
       112
       +
                   .memory_type = memory_type,

     

       72
       113
        
                   .underlying = pte,

     

       73
       114
        
                   .perms = .{

     

       74
       74
       -
                       .writable = pte.writable,

     

       75
       75
       -
                       .executable = !pte.nx,

     

       76
       76
       -
                       .userspace_accessible = pte.user_accessible,

     

       115
       115
       +
                       .w = pte.writable,

     

       116
       116
       +
                       .x = !pte.nx,

     

       117
       117
       +
                       .u = pte.user_accessible,

     

       118
       118
       +
                   },

     

       119
       119
       +
               };

     

       120
       120
       +
           }

     

       121
       121
       +
       

     

       122
       122
       +
           pub fn decode_memory_type(_: *Self, pte: *PageTable.Entry, _: u3) ?MemoryType {

     

       123
       123
       +
               return switch (pte.disable_cache) {

     

       124
       124
       +
                   true => .DeviceUncacheable,

     

       125
       125
       +
                   false => switch (pte.write_through) {

     

       126
       126
       +
                       true => .MemoryWritethrough,

     

       127
       127
       +
                       false => .MemoryWriteBack,

     

       77
       128
        
                   },

     

       78
       129
        
               };

     

       79
       130
        
           }

     

       80
       131
        
       

     

       81
       81
       -
           pub fn decode_mapping(pte: *PageTable.Entry, level: u3) MappingHandle {

     

       132
       132
       +
           pub fn encode_memory_type(_: *Self, pte: *PageTable.Entry, mapping_handle: MappingHandle) void {

     

       133
       133
       +
               switch (mapping_handle.memory_type.?) {

     

       134
       134
       +
                   .MemoryWritethrough => pte.write_through = true,

     

       135
       135
       +
                   .DeviceUncacheable => pte.disable_cache = true,

     

       136
       136
       +
                   .MemoryWriteBack => {},

     

       137
       137
       +
                   else => @panic("bad memory type"),

     

       138
       138
       +
               }

     

       139
       139
       +
           }

     

       140
       140
       +
       

     

       141
       141
       +
           pub fn parse_table(self: *Self, pte: *PageTable.Entry, level: u3) TableHandle {

     

       82
       142
        
               return .{

     

       83
       83
       -
                   .phys_addr = pte.getAddr(),

     

       143
       143
       +
                   .context = self,

     

       144
       144
       +
                   .paddr = pte.getAddr(),

     

       84
       145
        
                   .level = level,

     

       85
       85
       -
                   // TODO: memory types

     

       86
       86
       -
                   .memory_type = null,

     

       87
       146
        
                   .underlying = pte,

     

       88
       147
        
                   .perms = .{

     

       89
       89
       -
                       .writable = pte.writable,

     

       90
       90
       -
                       .executable = !pte.nx,

     

       91
       91
       -
                       .userspace_accessible = pte.user_accessible,

     

       148
       148
       +
                       .w = pte.writable,

     

       149
       149
       +
                       .x = !pte.nx,

     

       150
       150
       +
                       .u = pte.user_accessible,

     

       92
       151
        
                   },

     

       93
       152
        
               };

     

       94
       153
        
           }

     

       154
       154
       +
       

     

       155
       155
       +
           pub fn encode_mapping(self: *Self, mapping_handle: MappingHandle) PageTable.Entry {

     

       156
       156
       +
               var pte = std.mem.zeroes(PageTable.Entry);

     

       157
       157
       +
               pte.setAddr(mapping_handle.paddr);

     

       158
       158
       +
               pte.present = true;

     

       159
       159
       +
               if (mapping_handle.level != 0) {

     

       160
       160
       +
                   pte.huge = true;

     

       161
       161
       +
               }

     

       162
       162
       +
       

     

       163
       163
       +
               pte.writable = mapping_handle.perms.w;

     

       164
       164
       +
               pte.user_accessible = mapping_handle.perms.u;

     

       165
       165
       +
               pte.nx = !mapping_handle.perms.x;

     

       166
       166
       +
       

     

       167
       167
       +
               self.encode_memory_type(&pte, mapping_handle);

     

       168
       168
       +
               return pte;

     

       169
       169
       +
           }

     

       170
       170
       +
       

     

       171
       171
       +
           pub fn encode_table(_: *Self, table_handle: TableHandle) PageTable.Entry {

     

       172
       172
       +
               var pte = std.mem.zeroes(PageTable.Entry);

     

       173
       173
       +
               pte.writable = table_handle.perms.w;

     

       174
       174
       +
               pte.user_accessible = table_handle.perms.u;

     

       175
       175
       +
               pte.nx = !table_handle.perms.x;

     

       176
       176
       +
               pte.setAddr(table_handle.paddr);

     

       177
       177
       +
       

     

       178
       178
       +
               pte.present = true;

     

       179
       179
       +
               pte.huge = false;

     

       180
       180
       +
       

     

       181
       181
       +
               return pte;

     

       182
       182
       +
           }

     

       183
       183
       +
       

     

       184
       184
       +
           pub fn invalidate(_: *const Self, vaddr: u64) void {

     

       185
       185
       +
               asm volatile (

     

       186
       186
       +
                   \\ invlpg (%[vaddr])

     

       187
       187
       +
                   :

     

       188
       188
       +
                   : [vaddr] "r" (vaddr),

     

       189
       189
       +
                   : .{ .memory = true });

     

       190
       190
       +
           }

     

       191
       191
       +
       

     

       192
       192
       +
           pub fn domain(_: *const Self, level: u3, vaddr: u64) StupidSlice {

     

       193
       193
       +
               return .{

     

       194
       194
       +
                   .ptr = vaddr & ~(page_sizes[level] - 1),

     

       195
       195
       +
                   .len = page_sizes[level],

     

       196
       196
       +
               };

     

       197
       197
       +
           }

     

       198
       198
       +
       

     

       199
       199
       +
           pub fn virt_to_phys(context: *Context, vaddr: usize) ?usize {

     

       200
       200
       +
               const root = context.root_table(0).get_children();

     

       201
       201
       +
               const indexes = [_]usize{

     

       202
       202
       +
                   (vaddr >> 39) & 0x1FF,

     

       203
       203
       +
                   (vaddr >> 30) & 0x1FF,

     

       204
       204
       +
                   (vaddr >> 21) & 0x1FF,

     

       205
       205
       +
                   (vaddr >> 12) & 0x1FF,

     

       206
       206
       +
               };

     

       207
       207
       +
               var pte_ptr = &root[indexes[0]];

     

       208
       208
       +
               std.log.warn("{*}: {any}, addr 0x{x}", .{ pte_ptr, pte_ptr, pte_ptr.getAddr() });

     

       209
       209
       +
               for (0..3) |i| {

     

       210
       210
       +
                   if (!pte_ptr.present) {

     

       211
       211
       +
                       return null;

     

       212
       212
       +
                   }

     

       213
       213
       +
                   const next_page_table = common.mm.physToHHDM(*PageTable, pte_ptr.getAddr());

     

       214
       214
       +
                   pte_ptr = &next_page_table.entries[indexes[i + 1]];

     

       215
       215
       +
                   std.log.warn("{*}: {any}, addr 0x{x}", .{ pte_ptr, pte_ptr, pte_ptr.getAddr() });

     

       216
       216
       +
               }

     

       217
       217
       +
               return pte_ptr.getAddr() + (vaddr & 0xFFF);

     

       218
       218
       +
           }

     

       95
       219
        
       };

     

       96
       220
        
       

     

       97
       97
       -
       pub const MappingHandle = struct {

     

       98
       98
       -
           phys_addr: usize,

     

       221
       221
       +
       fn idx_from_level(vaddr: u64, level: u6) u9 {

     

       222
       222
       +
           const shamt = 12 + level * 9;

     

       223
       223
       +
           return @truncate(vaddr >> shamt);

     

       224
       224
       +
       }

     

       225
       225
       +
       

     

       226
       226
       +
       pub fn make_page_table() !usize {

     

       227
       227
       +
           const page_size = std.heap.pageSize();

     

       228
       228
       +
           const paddr = try common.init_data.bootmem.allocPhys(page_size);

     

       229
       229
       +
           const pt_ptr = common.mm.physToHHDM([*]u8, paddr);

     

       230
       230
       +
           @memset(pt_ptr[0..page_size], 0);

     

       231
       231
       +
           return paddr;

     

       232
       232
       +
       }

     

       233
       233
       +
       

     

       234
       234
       +
       pub const page_sizes = [_]usize{

     

       235
       235
       +
           0x1000, // 4K

     

       236
       236
       +
           0x200000, // 2M

     

       237
       237
       +
           0x40000000, // 1G

     

       238
       238
       +
           0x8000000000, // 512G

     

       239
       239
       +
           0x1000000000000, // 256T

     

       240
       240
       +
       };

     

       241
       241
       +
       

     

       242
       242
       +
       const MappingHandle = struct {

     

       243
       243
       +
           paddr: u64,

     

       99
       244
        
           level: u3,

     

       100
       245
        
           memory_type: ?MemoryType,

     

       246
       246
       +
           context: *Context,

     

       101
       247
        
           perms: Perms,

     

       102
       248
        
           underlying: *PageTable.Entry,

     

       103
       249
        
       };

     

       104
       250
        
       

     

       105
       251
        
       pub const TableHandle = struct {

     

       106
       106
       -
           phys_addr: usize,

     

       252
       252
       +
           paddr: u64,

     

       107
       253
        
           level: u3,

     

       254
       254
       +
           context: *Context,

     

       108
       255
        
           perms: Perms,

     

       109
       256
        
           underlying: ?*PageTable.Entry,

     

       110
       257
        
       

     

       111
       258
        
           const Self = @This();

     

       112
       112
       -
       

     

       113
       113
       -
           // Get the child entries of this page table

     

       114
       259
        
           pub fn get_children(self: *const Self) []PageTable.Entry {

     

       115
       115
       -
               const page_table = physToVirt(*PageTable, self.phys_addr);

     

       116
       116
       -
               return page_table.entries[0..];

     

       260
       260
       +
               const pt = common.mm.physToHHDM(*PageTable, self.paddr);

     

       261
       261
       +
               return pt.entries[0..];

     

       117
       262
        
           }

     

       118
       263
        
       

     

       119
       119
       -
           // Get children from the position holding the table and on

     

       120
       120
       -
           pub fn skip_to(self: *const Self, vaddr: usize) []PageTable.Entry {

     

       121
       121
       -
               return self.get_children()[extract_index_from_vaddr(vaddr, self.level - 1)..];

     

       264
       264
       +
           pub fn skip_to(self: *const Self, vaddr: u64) []PageTable.Entry {

     

       265
       265
       +
               return self.get_children()[idx_from_level(vaddr, self.level - 1)..];

     

       122
       266
        
           }

     

       123
       267
        
       

     

       124
       124
       -
           // Decode child table given an entry

     

       125
       125
       -
           pub fn decode_child(self: *const Self, pte: *PageTable.Entry) TypedPTE {

     

       126
       126
       -
               return TypedPTE.decode(pte, self.level - 1);

     

       268
       268
       +
           pub fn decode_child(self: *const Self, pte: *PageTable.Entry) SomePteHandle {

     

       269
       269
       +
               return self.context.decode(pte, self.level - 1);

     

       127
       270
        
           }

     

       128
       271
        
       

     

       129
       272
        
           pub fn addPerms(self: *const Self, perms: Perms) void {

     

       130
       130
       -
               if (perms.executable) {

     

       273
       273
       +
               if (perms.x) {

     

       131
       274
        
                   self.underlying.?.nx = false;

     

       132
       275
        
               }

     

       133
       133
       -
               if (perms.writable) {

     

       276
       276
       +
               if (perms.w) {

     

       134
       277
        
                   self.underlying.?.writable = true;

     

       135
       278
        
               }

     

       136
       136
       -
               if (perms.userspace_accessible) {

     

       279
       279
       +
               if (perms.u) {

     

       137
       280
        
                   self.underlying.?.user_accessible = true;

     

       138
       281
        
               }

     

       139
       282
        
           }

     

       140
       283
        
       

     

       141
       141
       -
           pub fn child_domain(self: *const Self, vaddr: usize) UntypedSlice {

     

       142
       142
       -
               return domain(vaddr, self.level - 1);

     

       143
       143
       -
           }

     

       144
       144
       -
       

     

       145
       284
        
           pub fn make_child_table(self: *const Self, pte: *PageTable.Entry, perms: Perms) !TableHandle {

     

       146
       285
        
               const pmem = try make_page_table();

     

       147
       286
        
       

     

       148
       287
        
               const result: TableHandle = .{

     

       149
       149
       -
                   .phys_addr = pmem,

     

       288
       288
       +
                   .paddr = pmem,

     

       289
       289
       +
                   .context = self.context,

     

       150
       290
        
                   .level = self.level - 1,

     

       151
       291
        
                   .perms = perms,

     

       152
       292
        
                   .underlying = pte,

     

       153
       293
        
               };

     

       154
       154
       -
               pte.* = encode_table(result);

     

       294
       294
       +
               pte.* = self.context.encode_table(result);

     

       155
       295
        
       

     

       156
       296
        
               return result;

     

       157
       297
        
           }

     

       158
       298
        
       

     

       159
       159
       -
           pub fn make_child_mapping(

     

       160
       160
       -
               self: *const Self,

     

       161
       161
       -
               pte: *PageTable.Entry,

     

       162
       162
       -
               paddr: ?usize,

     

       163
       163
       -
               perms: Perms,

     

       164
       164
       -
               memory_type: MemoryType,

     

       165
       165
       -
           ) !MappingHandle {

     

       299
       299
       +
           pub fn make_child_mapping(self: *const Self, pte: *PageTable.Entry, paddr: ?u64, perms: Perms, memory_type: MemoryType) !MappingHandle {

     

       166
       300
        
               const page_size = page_sizes[self.level - 1];

     

       167
       301
        
               const pmem = paddr orelse try common.init_data.bootmem.allocPhys(page_size);

     

       168
       302
        
       

     

       169
       303
        
               const result: MappingHandle = .{

     

       170
       304
        
                   .level = self.level - 1,

     

       171
       305
        
                   .memory_type = memory_type,

     

       306
       306
       +
                   .context = self.context,

     

       172
       307
        
                   .perms = perms,

     

       173
       308
        
                   .underlying = pte,

     

       174
       174
       -
                   .phys_addr = pmem,

     

       309
       309
       +
                   .paddr = pmem,

     

       175
       310
        
               };

     

       176
       311
        
       

     

       177
       177
       -
               pte.* = encode_mapping(result);

     

       312
       312
       +
               pte.* = self.context.encode_mapping(result);

     

       178
       313
        
       

     

       179
       314
        
               return result;

     

       180
       315
        
           }

     

       181
       181
       -
       };

     

       182
       316
        
       

     

       183
       183
       -
       pub fn root_table(vaddr: usize) TableHandle {

     

       184
       184
       -
           _ = vaddr;

     

       185
       185
       -
           const cr3_val = arch.registers.ControlRegisters.Cr3.read() & 0xFFFF_FFFF_FFFF_F000;

     

       186
       186
       -
           return .{

     

       187
       187
       -
               .phys_addr = cr3_val,

     

       188
       188
       -
               // TODO: detect and support 5 level paging!

     

       189
       189
       -
               .level = 4,

     

       190
       190
       -
               .perms = .{

     

       191
       191
       -
                   .executable = true,

     

       192
       192
       -
                   .writable = true,

     

       193
       193
       -
               },

     

       194
       194
       -
               .underlying = null,

     

       195
       195
       -
           };

     

       196
       196
       -
       }

     

       197
       197
       -
       

     

       198
       198
       -
       fn encode_table(pte_handle: TableHandle) PageTable.Entry {

     

       199
       199
       -
           var pte = std.mem.zeroes(PageTable.Entry);

     

       200
       200
       -
       

     

       201
       201
       -
           pte.setAddr(pte_handle.phys_addr);

     

       202
       202
       -
           pte.writable = pte_handle.perms.writable;

     

       203
       203
       -
           pte.user_accessible = pte_handle.perms.userspace_accessible;

     

       204
       204
       -
           pte.nx = !pte_handle.perms.executable;

     

       205
       205
       -
           pte.present = true;

     

       206
       206
       -
           pte.huge = false;

     

       207
       207
       -
       

     

       208
       208
       -
           return pte;

     

       209
       209
       -
       }

     

       210
       210
       -
       

     

       211
       211
       -
       fn encode_mapping(pte_handle: MappingHandle) PageTable.Entry {

     

       212
       212
       -
           var pte = std.mem.zeroes(PageTable.Entry);

     

       213
       213
       -
       

     

       214
       214
       -
           pte.setAddr(pte_handle.phys_addr);

     

       215
       215
       -
           pte.present = true;

     

       216
       216
       -
       

     

       217
       217
       -
           if (pte_handle.level != 0) {

     

       218
       218
       -
               pte.huge = true;

     

       317
       317
       +
           pub fn child_domain(self: *const Self, vaddr: u64) StupidSlice {

     

       318
       318
       +
               return self.context.domain(self.level - 1, vaddr);

     

       219
       319
        
           }

     

       220
       220
       -
       

     

       221
       221
       -
           pte.writable = pte_handle.perms.writable;

     

       222
       222
       -
           pte.user_accessible = pte_handle.perms.userspace_accessible;

     

       223
       223
       -
           pte.nx = !pte_handle.perms.executable;

     

       224
       224
       -
       

     

       225
       225
       -
           encode_memory_type(&pte, pte_handle);

     

       226
       226
       -
       

     

       227
       227
       -
           return pte;

     

       228
       228
       -
       }

     

       229
       229
       -
       

     

       230
       230
       -
       fn encode_memory_type(pte: *PageTable.Entry, pte_handle: MappingHandle) void {

     

       231
       231
       -
           const mt = pte_handle.memory_type orelse @panic("Unknown memory type");

     

       232
       232
       -
       

     

       233
       233
       -
           // TODO: Page Attribute Table

     

       234
       234
       -
           switch (mt) {

     

       235
       235
       -
               .MemoryWritethrough => pte.write_through = true,

     

       236
       236
       -
               .DeviceUncacheable => pte.disable_cache = true,

     

       237
       237
       -
               .MemoryWriteBack => {},

     

       238
       238
       -
               else => @panic("Cannot set memory type"),

     

       239
       239
       -
           }

     

       240
       240
       -
       }

     

       320
       320
       +
       };

     

       241
       321
        
       

     

       242
       242
       -
       /// Returns physical address

     

       243
       243
       -
       fn make_page_table() !usize {

     

       244
       244
       -
           const pt_phys = try common.init_data.bootmem.allocPhys(std.heap.pageSize());

     

       245
       245
       -
           const pt = physToVirt([*]u8, pt_phys);

     

       246
       246
       -
           @memset(pt[0..std.heap.pageSize()], 0x00);

     

       247
       247
       -
           return pt_phys;

     

       248
       248
       -
       }

     

       322
       322
       +
       pub const SomePteHandle = union(common.mm.paging.PTEType) {

     

       323
       323
       +
           Mapping: MappingHandle,

     

       324
       324
       +
           Table: TableHandle,

     

       325
       325
       +
           Empty,

     

       326
       326
       +
       };

     

       249
       327
        
       

     

       250
       250
       -
       pub fn invalidate(vaddr: u64) void {

     

       251
       251
       -
           asm volatile (

     

       252
       252
       -
               \\ invlpg (%[vaddr])

     

       253
       253
       -
               :

     

       254
       254
       -
               : [vaddr] "r" (vaddr),

     

       255
       255
       -
               : .{ .memory = true });

     

       256
       256
       -
       }

     

       257
       257
       -
       

     

       258
       258
       -
       const UntypedSlice = struct {

     

       328
       328
       +
       pub const StupidSlice = struct {

     

       259
       329
        
           len: usize,

     

       260
       330
        
           ptr: usize,

     

       261
       331
        
       };

     

       262
       262
       -
       

     

       263
       263
       -
       pub fn domain(vaddr: usize, level: u3) UntypedSlice {

     

       264
       264
       -
           return .{

     

       265
       265
       -
               .len = page_sizes[level],

     

       266
       266
       -
               .ptr = vaddr & ~(page_sizes[level] - 1),

     

       267
       267
       -
           };

     

       268
       268
       -
       }

     

       269
       269
       -
       

     

       270
       270
       -
       pub const MemoryType = enum {

     

       271
       271
       -
           DeviceUncacheable,

     

       272
       272
       -
           DeviceWriteCombining,

     

       273
       273
       -
           MemoryWritethrough,

     

       274
       274
       -
           MemoryWriteBack,

     

       275
       275
       -
       };

     

       276
       276
       -
       

     

       277
       277
       -
       pub fn can_map_at(level: u3) bool {

     

       278
       278
       -
           return level < 2;

     

       279
       279
       -
       }

+6 -4

components/ukernel/common/loader.zig

···

       1
       1
        
       const common = @import("root.zig");

     

       2
       2
       +
       const arch = @import("arch");

     

       2
       3
        
       const paging = common.mm.paging;

     

       3
       4
        
       const std = @import("std");

     

       4
       5
        
       const elf = std.elf;

     

       5
       6
        
       const log = std.log.scoped(.elf_loader);

     

       6
       7
        
       

     

       7
       8
        
       // Load root task, return the entry point

     

       8
       8
       -
       pub fn loadRootTask() !usize {

     

       9
       9
       +
       pub fn loadRootTask(context: *arch.mm.paging.Context) !usize {

     

       9
       10
        
           const root_task = common.init_data.root_task;

     

       10
       11
        
           const hdr = blk: {

     

       11
       12
        
               const hdr: *elf.Elf64_Ehdr = @ptrCast(root_task);

     
···

       27
       28
        
                   .size = memsz_pages,

     

       28
       29
        
                   .memory_type = .MemoryWriteBack,

     

       29
       30
        
                   .perms = .{

     

       30
       30
       -
                       .executable = entry.p_flags & elf.PF_X > 0,

     

       31
       31
       -
                       .writable = entry.p_flags & elf.PF_W > 0,

     

       32
       32
       -
                       .userspace_accessible = true,

     

       31
       31
       +
                       .x = entry.p_flags & elf.PF_X > 0,

     

       32
       32
       +
                       .w = entry.p_flags & elf.PF_W > 0,

     

       33
       33
       +
                       .u = true,

     

       33
       34
        
                   },

     

       35
       35
       +
                   .context = context,

     

       34
       36
        
               });

     

       35
       37
        
       

     

       36
       38
        
               // 2. Copy filesz bytes from offset to this new page

+24 -17

components/ukernel/common/mm/paging.zig

···

       2
       2
        
       const std = @import("std");

     

       3
       3
        
       const TableHandle = arch.mm.paging.TableHandle;

     

       4
       4
        
       const MemoryType = arch.mm.paging.MemoryType;

     

       5
       5
       +
       const Context = arch.mm.paging.Context;

     

       5
       6
        
       

     

       6
       7
        
       pub const Perms = struct {

     

       7
       7
       -
           writable: bool,

     

       8
       8
       -
           executable: bool,

     

       9
       9
       -
           userspace_accessible: bool = false,

     

       8
       8
       +
           /// Writable

     

       9
       9
       +
           w: bool,

     

       10
       10
       +
           /// Executable

     

       11
       11
       +
           x: bool,

     

       12
       12
       +
           /// Userspace Accessible

     

       13
       13
       +
           u: bool = false,

     

       10
       14
        
       

     

       11
       15
        
           const Self = @This();

     

       12
       16
        
       

     

       13
       17
        
           /// Verify that the current permissions are a superset of the provided ones

     

       14
       18
        
           pub fn allows(self: Self, other: Self) bool {

     

       15
       15
       -
               if (!self.writable and other.writable) {

     

       19
       19
       +
               if (!self.w and other.w) {

     

       16
       20
        
                   return false;

     

       17
       21
        
               }

     

       18
       18
       -
               if (!self.executable and other.executable) {

     

       22
       22
       +
               if (!self.x and other.x) {

     

       19
       23
        
                   return false;

     

       20
       24
        
               }

     

       21
       21
       -
               if (!self.userspace_accessible and other.userspace_accessible) {

     

       25
       25
       +
               if (!self.u and other.u) {

     

       22
       26
        
                   return false;

     

       23
       27
        
               }

     

       24
       28
        
               return true;

     
···

       27
       31
        
           /// OR two permissions

     

       28
       32
        
           pub fn addPerms(self: Self, other: Self) Self {

     

       29
       33
        
               return .{

     

       30
       30
       -
                   .writable = self.writable or other.writable,

     

       31
       31
       -
                   .executable = self.executable or other.executable,

     

       32
       32
       -
                   .userspace = self.userspace_accessible or other.userspace_accessible,

     

       34
       34
       +
                   .w = self.w or other.w,

     

       35
       35
       +
                   .x = self.x or other.x,

     

       36
       36
       +
                   .u = self.u or other.u,

     

       33
       37
        
               };

     

       34
       38
        
           }

     

       35
       39
        
       };

     
···

       42
       46
        
           size: usize,

     

       43
       47
        
           perms: Perms,

     

       44
       48
        
           memory_type: MemoryType,

     

       49
       49
       +
           context: *Context,

     

       45
       50
        
       }) !void {

     

       46
       46
       -
           const root = arch.mm.paging.root_table(args.vaddr);

     

       51
       51
       +
           const root = args.context.root_table(args.vaddr);

     

       47
       52
        
           var vaddr = args.vaddr;

     

       48
       53
        
           var paddr = args.paddr;

     

       49
       54
        
           var size = args.size;

     

       50
       50
       -
           try mapPageImpl(&vaddr, &paddr, &size, root, args.perms, args.memory_type);

     

       55
       55
       +
           try mapPageImpl(&vaddr, &paddr, &size, root, args.perms, args.memory_type, args.context);

     

       51
       56
        
       }

     

       52
       57
        
       

     

       53
       58
        
       pub fn map(args: struct {

     
···

       55
       60
        
           size: usize,

     

       56
       61
        
           perms: Perms,

     

       57
       62
        
           memory_type: MemoryType,

     

       63
       63
       +
           context: *Context,

     

       58
       64
        
       }) !void {

     

       59
       59
       -
           const root = arch.mm.paging.root_table(args.vaddr);

     

       65
       65
       +
           const root = args.context.root_table(args.vaddr);

     

       60
       66
        
           var vaddr = args.vaddr;

     

       61
       67
        
           var size = args.size;

     

       62
       62
       -
           try mapPageImpl(&vaddr, null, &size, root, args.perms, args.memory_type);

     

       68
       68
       +
           try mapPageImpl(&vaddr, null, &size, root, args.perms, args.memory_type, args.context);

     

       63
       69
        
       }

     

       64
       70
        
       

     

       65
       71
        
       fn mapPageImpl(

     
···

       69
       75
        
           table: TableHandle,

     

       70
       76
        
           perms: Perms,

     

       71
       77
        
           memory_type: MemoryType,

     

       78
       78
       +
           context: *Context,

     

       72
       79
        
       ) !void {

     

       73
       80
        
           // 1. Get slice of every child from the target forwards

     

       74
       81
        
           const children = table.skip_to(vaddr.*);

     
···

       84
       91
        
               switch (table.decode_child(child)) {

     

       85
       92
        
                   .Mapping => return error.AlreadyPresent,

     

       86
       93
        
                   .Table => |*tbl| {

     

       87
       87
       -
                       try mapPageImpl(vaddr, paddr, size, tbl.*, perms, memory_type);

     

       94
       94
       +
                       try mapPageImpl(vaddr, paddr, size, tbl.*, perms, memory_type, context);

     

       88
       95
        
                       if (!tbl.perms.allows(perms)) {

     

       89
       96
        
                           tbl.addPerms(perms);

     

       90
       90
       -
                           arch.mm.paging.invalidate(vaddr.*);

     

       97
       97
       +
                           context.invalidate(vaddr.*);

     

       91
       98
        
                       }

     

       92
       99
        
                   },

     

       93
       100
        
                   .Empty => {

     

       94
       101
        
                       const domain = table.child_domain(vaddr.*);

     

       95
       95
       -
                       if (domain.ptr == vaddr.* and domain.len <= size.* and arch.mm.paging.can_map_at(table.level - 1) and is_aligned(vaddr.*, paddr, table.level - 1)) {

     

       102
       102
       +
                       if (domain.ptr == vaddr.* and domain.len <= size.* and context.can_map_at(table.level - 1) and is_aligned(vaddr.*, paddr, table.level - 1)) {

     

       96
       103
        
                           // Make child mapping etc

     

       97
       104
        
                           _ = try table.make_child_mapping(child, if (paddr) |p| p.* else null, perms, memory_type);

     

       98
       105
        
                           const step = domain.len;

     
···

       108
       115
        
                           }

     

       109
       116
        
                       } else {

     

       110
       117
        
                           const tbl = try table.make_child_table(child, perms);

     

       111
       111
       -
                           try mapPageImpl(vaddr, paddr, size, tbl, perms, memory_type);

     

       118
       118
       +
                           try mapPageImpl(vaddr, paddr, size, tbl, perms, memory_type, context);

     

       112
       119
        
                       }

     

       113
       120
        
                   },

     

       114
       121
        
               }