Fix runsc syscall documentation generation.

We can register any number of tables with any number of architectures, and
need not limit the definitions to the architecture in question. This allows
runsc to generate documentation for all architectures simultaneously.

Similarly, this simplifies the VFSv2 patching process.

PiperOrigin-RevId: 310224827

5 files changed, 173 insertions, 211 deletions

diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD
index ffca627d4..4c7b8f819 100644
--- a/pkg/sentry/syscalls/linux/vfs2/BUILD
+++ b/pkg/sentry/syscalls/linux/vfs2/BUILD
@@ -13,9 +13,6 @@ go_library(
         "fscontext.go",
         "getdents.go",
         "ioctl.go",
-        "linux64.go",
-        "linux64_override_amd64.go",
-        "linux64_override_arm64.go",
         "mmap.go",
         "path.go",
         "pipe.go",
@@ -28,6 +25,7 @@ go_library(
         "stat_arm64.go",
         "sync.go",
         "timerfd.go",
+        "vfs2.go",
         "xattr.go",
     ],
     marshal = True,
diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64.go b/pkg/sentry/syscalls/linux/vfs2/linux64.go
deleted file mode 100644
index 19ee36081..000000000
--- a/pkg/sentry/syscalls/linux/vfs2/linux64.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package vfs2 provides syscall implementations that use VFS2.
-package vfs2
diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go b/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go
deleted file mode 100644
index 47c5d18e7..000000000
--- a/pkg/sentry/syscalls/linux/vfs2/linux64_override_amd64.go
+++ /dev/null
@@ -1,165 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build amd64
-
-package vfs2
-
-import (
-	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/sentry/syscalls"
-)
-
-// Override syscall table to add syscalls implementations from this package.
-func Override(table map[uintptr]kernel.Syscall) {
-	table[0] = syscalls.Supported("read", Read)
-	table[1] = syscalls.Supported("write", Write)
-	table[2] = syscalls.Supported("open", Open)
-	table[3] = syscalls.Supported("close", Close)
-	table[4] = syscalls.Supported("stat", Stat)
-	table[5] = syscalls.Supported("fstat", Fstat)
-	table[6] = syscalls.Supported("lstat", Lstat)
-	table[7] = syscalls.Supported("poll", Poll)
-	table[8] = syscalls.Supported("lseek", Lseek)
-	table[9] = syscalls.Supported("mmap", Mmap)
-	table[16] = syscalls.Supported("ioctl", Ioctl)
-	table[17] = syscalls.Supported("pread64", Pread64)
-	table[18] = syscalls.Supported("pwrite64", Pwrite64)
-	table[19] = syscalls.Supported("readv", Readv)
-	table[20] = syscalls.Supported("writev", Writev)
-	table[21] = syscalls.Supported("access", Access)
-	table[22] = syscalls.Supported("pipe", Pipe)
-	table[23] = syscalls.Supported("select", Select)
-	table[32] = syscalls.Supported("dup", Dup)
-	table[33] = syscalls.Supported("dup2", Dup2)
-	delete(table, 40) // sendfile
-	table[41] = syscalls.Supported("socket", Socket)
-	table[42] = syscalls.Supported("connect", Connect)
-	table[43] = syscalls.Supported("accept", Accept)
-	table[44] = syscalls.Supported("sendto", SendTo)
-	table[45] = syscalls.Supported("recvfrom", RecvFrom)
-	table[46] = syscalls.Supported("sendmsg", SendMsg)
-	table[47] = syscalls.Supported("recvmsg", RecvMsg)
-	table[48] = syscalls.Supported("shutdown", Shutdown)
-	table[49] = syscalls.Supported("bind", Bind)
-	table[50] = syscalls.Supported("listen", Listen)
-	table[51] = syscalls.Supported("getsockname", GetSockName)
-	table[52] = syscalls.Supported("getpeername", GetPeerName)
-	table[53] = syscalls.Supported("socketpair", SocketPair)
-	table[54] = syscalls.Supported("setsockopt", SetSockOpt)
-	table[55] = syscalls.Supported("getsockopt", GetSockOpt)
-	table[59] = syscalls.Supported("execve", Execve)
-	table[72] = syscalls.Supported("fcntl", Fcntl)
-	delete(table, 73) // flock
-	table[74] = syscalls.Supported("fsync", Fsync)
-	table[75] = syscalls.Supported("fdatasync", Fdatasync)
-	table[76] = syscalls.Supported("truncate", Truncate)
-	table[77] = syscalls.Supported("ftruncate", Ftruncate)
-	table[78] = syscalls.Supported("getdents", Getdents)
-	table[79] = syscalls.Supported("getcwd", Getcwd)
-	table[80] = syscalls.Supported("chdir", Chdir)
-	table[81] = syscalls.Supported("fchdir", Fchdir)
-	table[82] = syscalls.Supported("rename", Rename)
-	table[83] = syscalls.Supported("mkdir", Mkdir)
-	table[84] = syscalls.Supported("rmdir", Rmdir)
-	table[85] = syscalls.Supported("creat", Creat)
-	table[86] = syscalls.Supported("link", Link)
-	table[87] = syscalls.Supported("unlink", Unlink)
-	table[88] = syscalls.Supported("symlink", Symlink)
-	table[89] = syscalls.Supported("readlink", Readlink)
-	table[90] = syscalls.Supported("chmod", Chmod)
-	table[91] = syscalls.Supported("fchmod", Fchmod)
-	table[92] = syscalls.Supported("chown", Chown)
-	table[93] = syscalls.Supported("fchown", Fchown)
-	table[94] = syscalls.Supported("lchown", Lchown)
-	table[132] = syscalls.Supported("utime", Utime)
-	table[133] = syscalls.Supported("mknod", Mknod)
-	table[137] = syscalls.Supported("statfs", Statfs)
-	table[138] = syscalls.Supported("fstatfs", Fstatfs)
-	table[161] = syscalls.Supported("chroot", Chroot)
-	table[162] = syscalls.Supported("sync", Sync)
-	delete(table, 165) // mount
-	delete(table, 166) // umount2
-	delete(table, 187) // readahead
-	table[188] = syscalls.Supported("setxattr", Setxattr)
-	table[189] = syscalls.Supported("lsetxattr", Lsetxattr)
-	table[190] = syscalls.Supported("fsetxattr", Fsetxattr)
-	table[191] = syscalls.Supported("getxattr", Getxattr)
-	table[192] = syscalls.Supported("lgetxattr", Lgetxattr)
-	table[193] = syscalls.Supported("fgetxattr", Fgetxattr)
-	table[194] = syscalls.Supported("listxattr", Listxattr)
-	table[195] = syscalls.Supported("llistxattr", Llistxattr)
-	table[196] = syscalls.Supported("flistxattr", Flistxattr)
-	table[197] = syscalls.Supported("removexattr", Removexattr)
-	table[198] = syscalls.Supported("lremovexattr", Lremovexattr)
-	table[199] = syscalls.Supported("fremovexattr", Fremovexattr)
-	delete(table, 206) // io_setup
-	delete(table, 207) // io_destroy
-	delete(table, 208) // io_getevents
-	delete(table, 209) // io_submit
-	delete(table, 210) // io_cancel
-	table[213] = syscalls.Supported("epoll_create", EpollCreate)
-	table[217] = syscalls.Supported("getdents64", Getdents64)
-	delete(table, 221) // fdavise64
-	table[232] = syscalls.Supported("epoll_wait", EpollWait)
-	table[233] = syscalls.Supported("epoll_ctl", EpollCtl)
-	table[235] = syscalls.Supported("utimes", Utimes)
-	delete(table, 253) // inotify_init
-	delete(table, 254) // inotify_add_watch
-	delete(table, 255) // inotify_rm_watch
-	table[257] = syscalls.Supported("openat", Openat)
-	table[258] = syscalls.Supported("mkdirat", Mkdirat)
-	table[259] = syscalls.Supported("mknodat", Mknodat)
-	table[260] = syscalls.Supported("fchownat", Fchownat)
-	table[261] = syscalls.Supported("futimens", Futimens)
-	table[262] = syscalls.Supported("newfstatat", Newfstatat)
-	table[263] = syscalls.Supported("unlinkat", Unlinkat)
-	table[264] = syscalls.Supported("renameat", Renameat)
-	table[265] = syscalls.Supported("linkat", Linkat)
-	table[266] = syscalls.Supported("symlinkat", Symlinkat)
-	table[267] = syscalls.Supported("readlinkat", Readlinkat)
-	table[268] = syscalls.Supported("fchmodat", Fchmodat)
-	table[269] = syscalls.Supported("faccessat", Faccessat)
-	table[270] = syscalls.Supported("pselect", Pselect)
-	table[271] = syscalls.Supported("ppoll", Ppoll)
-	delete(table, 275) // splice
-	delete(table, 276) // tee
-	table[277] = syscalls.Supported("sync_file_range", SyncFileRange)
-	table[280] = syscalls.Supported("utimensat", Utimensat)
-	table[281] = syscalls.Supported("epoll_pwait", EpollPwait)
-	delete(table, 282) // signalfd
-	table[283] = syscalls.Supported("timerfd_create", TimerfdCreate)
-	table[284] = syscalls.Supported("eventfd", Eventfd)
-	delete(table, 285) // fallocate
-	table[286] = syscalls.Supported("timerfd_settime", TimerfdSettime)
-	table[287] = syscalls.Supported("timerfd_gettime", TimerfdGettime)
-	table[288] = syscalls.Supported("accept4", Accept4)
-	delete(table, 289) // signalfd4
-	table[290] = syscalls.Supported("eventfd2", Eventfd2)
-	table[291] = syscalls.Supported("epoll_create1", EpollCreate1)
-	table[292] = syscalls.Supported("dup3", Dup3)
-	table[293] = syscalls.Supported("pipe2", Pipe2)
-	delete(table, 294) // inotify_init1
-	table[295] = syscalls.Supported("preadv", Preadv)
-	table[296] = syscalls.Supported("pwritev", Pwritev)
-	table[299] = syscalls.Supported("recvmmsg", RecvMMsg)
-	table[306] = syscalls.Supported("syncfs", Syncfs)
-	table[307] = syscalls.Supported("sendmmsg", SendMMsg)
-	table[316] = syscalls.Supported("renameat2", Renameat2)
-	delete(table, 319) // memfd_create
-	table[322] = syscalls.Supported("execveat", Execveat)
-	table[327] = syscalls.Supported("preadv2", Preadv2)
-	table[328] = syscalls.Supported("pwritev2", Pwritev2)
-	table[332] = syscalls.Supported("statx", Statx)
-}
diff --git a/pkg/sentry/syscalls/linux/vfs2/linux64_override_arm64.go b/pkg/sentry/syscalls/linux/vfs2/linux64_override_arm64.go
deleted file mode 100644
index a6b367468..000000000
--- a/pkg/sentry/syscalls/linux/vfs2/linux64_override_arm64.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build arm64
-
-package vfs2
-
-import (
-	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/sentry/syscalls"
-)
-
-// Override syscall table to add syscalls implementations from this package.
-func Override(table map[uintptr]kernel.Syscall) {
-	table[63] = syscalls.Supported("read", Read)
-}
diff --git a/pkg/sentry/syscalls/linux/vfs2/vfs2.go b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
new file mode 100644
index 000000000..f1b697844
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
@@ -0,0 +1,172 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package vfs2 provides syscall implementations that use VFS2.
+package vfs2
+
+import (
+	"gvisor.dev/gvisor/pkg/sentry/syscalls"
+	"gvisor.dev/gvisor/pkg/sentry/syscalls/linux"
+)
+
+// Override syscall table to add syscalls implementations from this package.
+func Override() {
+	// Override AMD64.
+	s := linux.AMD64
+	s.Table[0] = syscalls.Supported("read", Read)
+	s.Table[1] = syscalls.Supported("write", Write)
+	s.Table[2] = syscalls.Supported("open", Open)
+	s.Table[3] = syscalls.Supported("close", Close)
+	s.Table[4] = syscalls.Supported("stat", Stat)
+	s.Table[5] = syscalls.Supported("fstat", Fstat)
+	s.Table[6] = syscalls.Supported("lstat", Lstat)
+	s.Table[7] = syscalls.Supported("poll", Poll)
+	s.Table[8] = syscalls.Supported("lseek", Lseek)
+	s.Table[9] = syscalls.Supported("mmap", Mmap)
+	s.Table[16] = syscalls.Supported("ioctl", Ioctl)
+	s.Table[17] = syscalls.Supported("pread64", Pread64)
+	s.Table[18] = syscalls.Supported("pwrite64", Pwrite64)
+	s.Table[19] = syscalls.Supported("readv", Readv)
+	s.Table[20] = syscalls.Supported("writev", Writev)
+	s.Table[21] = syscalls.Supported("access", Access)
+	s.Table[22] = syscalls.Supported("pipe", Pipe)
+	s.Table[23] = syscalls.Supported("select", Select)
+	s.Table[32] = syscalls.Supported("dup", Dup)
+	s.Table[33] = syscalls.Supported("dup2", Dup2)
+	delete(s.Table, 40) // sendfile
+	s.Table[41] = syscalls.Supported("socket", Socket)
+	s.Table[42] = syscalls.Supported("connect", Connect)
+	s.Table[43] = syscalls.Supported("accept", Accept)
+	s.Table[44] = syscalls.Supported("sendto", SendTo)
+	s.Table[45] = syscalls.Supported("recvfrom", RecvFrom)
+	s.Table[46] = syscalls.Supported("sendmsg", SendMsg)
+	s.Table[47] = syscalls.Supported("recvmsg", RecvMsg)
+	s.Table[48] = syscalls.Supported("shutdown", Shutdown)
+	s.Table[49] = syscalls.Supported("bind", Bind)
+	s.Table[50] = syscalls.Supported("listen", Listen)
+	s.Table[51] = syscalls.Supported("getsockname", GetSockName)
+	s.Table[52] = syscalls.Supported("getpeername", GetPeerName)
+	s.Table[53] = syscalls.Supported("socketpair", SocketPair)
+	s.Table[54] = syscalls.Supported("setsockopt", SetSockOpt)
+	s.Table[55] = syscalls.Supported("getsockopt", GetSockOpt)
+	s.Table[59] = syscalls.Supported("execve", Execve)
+	s.Table[72] = syscalls.Supported("fcntl", Fcntl)
+	delete(s.Table, 73) // flock
+	s.Table[74] = syscalls.Supported("fsync", Fsync)
+	s.Table[75] = syscalls.Supported("fdatasync", Fdatasync)
+	s.Table[76] = syscalls.Supported("truncate", Truncate)
+	s.Table[77] = syscalls.Supported("ftruncate", Ftruncate)
+	s.Table[78] = syscalls.Supported("getdents", Getdents)
+	s.Table[79] = syscalls.Supported("getcwd", Getcwd)
+	s.Table[80] = syscalls.Supported("chdir", Chdir)
+	s.Table[81] = syscalls.Supported("fchdir", Fchdir)
+	s.Table[82] = syscalls.Supported("rename", Rename)
+	s.Table[83] = syscalls.Supported("mkdir", Mkdir)
+	s.Table[84] = syscalls.Supported("rmdir", Rmdir)
+	s.Table[85] = syscalls.Supported("creat", Creat)
+	s.Table[86] = syscalls.Supported("link", Link)
+	s.Table[87] = syscalls.Supported("unlink", Unlink)
+	s.Table[88] = syscalls.Supported("symlink", Symlink)
+	s.Table[89] = syscalls.Supported("readlink", Readlink)
+	s.Table[90] = syscalls.Supported("chmod", Chmod)
+	s.Table[91] = syscalls.Supported("fchmod", Fchmod)
+	s.Table[92] = syscalls.Supported("chown", Chown)
+	s.Table[93] = syscalls.Supported("fchown", Fchown)
+	s.Table[94] = syscalls.Supported("lchown", Lchown)
+	s.Table[132] = syscalls.Supported("utime", Utime)
+	s.Table[133] = syscalls.Supported("mknod", Mknod)
+	s.Table[137] = syscalls.Supported("statfs", Statfs)
+	s.Table[138] = syscalls.Supported("fstatfs", Fstatfs)
+	s.Table[161] = syscalls.Supported("chroot", Chroot)
+	s.Table[162] = syscalls.Supported("sync", Sync)
+	delete(s.Table, 165) // mount
+	delete(s.Table, 166) // umount2
+	delete(s.Table, 187) // readahead
+	s.Table[188] = syscalls.Supported("setxattr", Setxattr)
+	s.Table[189] = syscalls.Supported("lsetxattr", Lsetxattr)
+	s.Table[190] = syscalls.Supported("fsetxattr", Fsetxattr)
+	s.Table[191] = syscalls.Supported("getxattr", Getxattr)
+	s.Table[192] = syscalls.Supported("lgetxattr", Lgetxattr)
+	s.Table[193] = syscalls.Supported("fgetxattr", Fgetxattr)
+	s.Table[194] = syscalls.Supported("listxattr", Listxattr)
+	s.Table[195] = syscalls.Supported("llistxattr", Llistxattr)
+	s.Table[196] = syscalls.Supported("flistxattr", Flistxattr)
+	s.Table[197] = syscalls.Supported("removexattr", Removexattr)
+	s.Table[198] = syscalls.Supported("lremovexattr", Lremovexattr)
+	s.Table[199] = syscalls.Supported("fremovexattr", Fremovexattr)
+	delete(s.Table, 206) // io_setup
+	delete(s.Table, 207) // io_destroy
+	delete(s.Table, 208) // io_getevents
+	delete(s.Table, 209) // io_submit
+	delete(s.Table, 210) // io_cancel
+	s.Table[213] = syscalls.Supported("epoll_create", EpollCreate)
+	s.Table[217] = syscalls.Supported("getdents64", Getdents64)
+	delete(s.Table, 221) // fdavise64
+	s.Table[232] = syscalls.Supported("epoll_wait", EpollWait)
+	s.Table[233] = syscalls.Supported("epoll_ctl", EpollCtl)
+	s.Table[235] = syscalls.Supported("utimes", Utimes)
+	delete(s.Table, 253) // inotify_init
+	delete(s.Table, 254) // inotify_add_watch
+	delete(s.Table, 255) // inotify_rm_watch
+	s.Table[257] = syscalls.Supported("openat", Openat)
+	s.Table[258] = syscalls.Supported("mkdirat", Mkdirat)
+	s.Table[259] = syscalls.Supported("mknodat", Mknodat)
+	s.Table[260] = syscalls.Supported("fchownat", Fchownat)
+	s.Table[261] = syscalls.Supported("futimens", Futimens)
+	s.Table[262] = syscalls.Supported("newfstatat", Newfstatat)
+	s.Table[263] = syscalls.Supported("unlinkat", Unlinkat)
+	s.Table[264] = syscalls.Supported("renameat", Renameat)
+	s.Table[265] = syscalls.Supported("linkat", Linkat)
+	s.Table[266] = syscalls.Supported("symlinkat", Symlinkat)
+	s.Table[267] = syscalls.Supported("readlinkat", Readlinkat)
+	s.Table[268] = syscalls.Supported("fchmodat", Fchmodat)
+	s.Table[269] = syscalls.Supported("faccessat", Faccessat)
+	s.Table[270] = syscalls.Supported("pselect", Pselect)
+	s.Table[271] = syscalls.Supported("ppoll", Ppoll)
+	delete(s.Table, 275) // splice
+	delete(s.Table, 276) // tee
+	s.Table[277] = syscalls.Supported("sync_file_range", SyncFileRange)
+	s.Table[280] = syscalls.Supported("utimensat", Utimensat)
+	s.Table[281] = syscalls.Supported("epoll_pwait", EpollPwait)
+	delete(s.Table, 282) // signalfd
+	s.Table[283] = syscalls.Supported("timerfd_create", TimerfdCreate)
+	s.Table[284] = syscalls.Supported("eventfd", Eventfd)
+	delete(s.Table, 285) // fallocate
+	s.Table[286] = syscalls.Supported("timerfd_settime", TimerfdSettime)
+	s.Table[287] = syscalls.Supported("timerfd_gettime", TimerfdGettime)
+	s.Table[288] = syscalls.Supported("accept4", Accept4)
+	delete(s.Table, 289) // signalfd4
+	s.Table[290] = syscalls.Supported("eventfd2", Eventfd2)
+	s.Table[291] = syscalls.Supported("epoll_create1", EpollCreate1)
+	s.Table[292] = syscalls.Supported("dup3", Dup3)
+	s.Table[293] = syscalls.Supported("pipe2", Pipe2)
+	delete(s.Table, 294) // inotify_init1
+	s.Table[295] = syscalls.Supported("preadv", Preadv)
+	s.Table[296] = syscalls.Supported("pwritev", Pwritev)
+	s.Table[299] = syscalls.Supported("recvmmsg", RecvMMsg)
+	s.Table[306] = syscalls.Supported("syncfs", Syncfs)
+	s.Table[307] = syscalls.Supported("sendmmsg", SendMMsg)
+	s.Table[316] = syscalls.Supported("renameat2", Renameat2)
+	delete(s.Table, 319) // memfd_create
+	s.Table[322] = syscalls.Supported("execveat", Execveat)
+	s.Table[327] = syscalls.Supported("preadv2", Preadv2)
+	s.Table[328] = syscalls.Supported("pwritev2", Pwritev2)
+	s.Table[332] = syscalls.Supported("statx", Statx)
+	s.Init()
+
+	// Override ARM64.
+	s = linux.ARM64
+	s.Table[63] = syscalls.Supported("read", Read)
+	s.Init()
+}