Convert memfs into proto-tmpfs.

- Renamed memfs to tmpfs.
- Copied fileRangeSet bits from fs/fsutil/ to fsimpl/tmpfs/
- Changed tmpfs to be backed by filemem instead of byte slice.
- regularFileReadWriter uses a sync.Pool, similar to gofer client.

PiperOrigin-RevId: 288356380

1 files changed, 92 insertions, 0 deletions

diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD
new file mode 100644
index 000000000..a5b285987
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/BUILD
@@ -0,0 +1,92 @@
+load("//tools/go_stateify:defs.bzl", "go_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_test")
+load("//tools/go_generics:defs.bzl", "go_template_instance")
+
+package(licenses = ["notice"])
+
+go_template_instance(
+    name = "dentry_list",
+    out = "dentry_list.go",
+    package = "tmpfs",
+    prefix = "dentry",
+    template = "//pkg/ilist:generic_list",
+    types = {
+        "Element": "*dentry",
+        "Linker": "*dentry",
+    },
+)
+
+go_library(
+    name = "tmpfs",
+    srcs = [
+        "dentry_list.go",
+        "directory.go",
+        "filesystem.go",
+        "named_pipe.go",
+        "regular_file.go",
+        "symlink.go",
+        "tmpfs.go",
+    ],
+    importpath = "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs",
+    deps = [
+        "//pkg/abi/linux",
+        "//pkg/amutex",
+        "//pkg/fspath",
+        "//pkg/log",
+        "//pkg/sentry/arch",
+        "//pkg/sentry/context",
+        "//pkg/sentry/fs",
+        "//pkg/sentry/fs/fsutil",
+        "//pkg/sentry/kernel",
+        "//pkg/sentry/kernel/auth",
+        "//pkg/sentry/kernel/pipe",
+        "//pkg/sentry/memmap",
+        "//pkg/sentry/pgalloc",
+        "//pkg/sentry/platform",
+        "//pkg/sentry/safemem",
+        "//pkg/sentry/usage",
+        "//pkg/sentry/usermem",
+        "//pkg/sentry/vfs",
+        "//pkg/syserror",
+    ],
+)
+
+go_test(
+    name = "benchmark_test",
+    size = "small",
+    srcs = ["benchmark_test.go"],
+    deps = [
+        ":tmpfs",
+        "//pkg/abi/linux",
+        "//pkg/fspath",
+        "//pkg/refs",
+        "//pkg/sentry/context",
+        "//pkg/sentry/context/contexttest",
+        "//pkg/sentry/fs",
+        "//pkg/sentry/fs/tmpfs",
+        "//pkg/sentry/kernel/auth",
+        "//pkg/sentry/vfs",
+        "//pkg/syserror",
+    ],
+)
+
+go_test(
+    name = "tmpfs_test",
+    size = "small",
+    srcs = [
+        "pipe_test.go",
+        "regular_file_test.go",
+    ],
+    embed = [":tmpfs"],
+    deps = [
+        "//pkg/abi/linux",
+        "//pkg/fspath",
+        "//pkg/sentry/context",
+        "//pkg/sentry/context/contexttest",
+        "//pkg/sentry/kernel/auth",
+        "//pkg/sentry/kernel/contexttest",
+        "//pkg/sentry/usermem",
+        "//pkg/sentry/vfs",
+        "//pkg/syserror",
+    ],
+)