gvisor/pkg/sentry/fs/fsutil/BUILD

119 lines
2.9 KiB
Python
Raw Normal View History

load("//tools:defs.bzl", "go_library", "go_test")
load("//tools/go_generics:defs.bzl", "go_template_instance")
package(licenses = ["notice"])
go_template_instance(
name = "dirty_set_impl",
out = "dirty_set_impl.go",
imports = {
"memmap": "gvisor.dev/gvisor/pkg/sentry/memmap",
"platform": "gvisor.dev/gvisor/pkg/sentry/platform",
},
package = "fsutil",
prefix = "Dirty",
template = "//pkg/segment:generic_set",
types = {
"Key": "uint64",
"Range": "memmap.MappableRange",
"Value": "DirtyInfo",
"Functions": "dirtySetFunctions",
},
)
go_template_instance(
name = "frame_ref_set_impl",
out = "frame_ref_set_impl.go",
imports = {
"platform": "gvisor.dev/gvisor/pkg/sentry/platform",
},
package = "fsutil",
VFS2 gofer client Updates #1198 Opening host pipes (by spinning in fdpipe) and host sockets is not yet complete, and will be done in a future CL. Major differences from VFS1 gofer client (sentry/fs/gofer), with varying levels of backportability: - "Cache policies" are replaced by InteropMode, which control the behavior of timestamps in addition to caching. Under InteropModeExclusive (analogous to cacheAll) and InteropModeWritethrough (analogous to cacheAllWritethrough), client timestamps are *not* written back to the server (it is not possible in 9P or Linux for clients to set ctime, so writing back client-authoritative timestamps results in incoherence between atime/mtime and ctime). Under InteropModeShared (analogous to cacheRemoteRevalidating), client timestamps are not used at all (remote filesystem clocks are authoritative). cacheNone is translated to InteropModeShared + new option filesystemOptions.specialRegularFiles. - Under InteropModeShared, "unstable attribute" reloading for permission checks, lookup, and revalidation are fused, which is feasible in VFS2 since gofer.filesystem controls path resolution. This results in a ~33% reduction in RPCs for filesystem operations compared to cacheRemoteRevalidating. For example, consider stat("/foo/bar/baz") where "/foo/bar/baz" fails revalidation, resulting in the instantiation of a new dentry: VFS1 RPCs: getattr("/") // fs.MountNamespace.FindLink() => fs.Inode.CheckPermission() => gofer.inodeOperations.check() => gofer.inodeOperations.UnstableAttr() walkgetattr("/", "foo") = fid1 // fs.Dirent.walk() => gofer.session.Revalidate() => gofer.cachePolicy.Revalidate() clunk(fid1) getattr("/foo") // CheckPermission walkgetattr("/foo", "bar") = fid2 // Revalidate clunk(fid2) getattr("/foo/bar") // CheckPermission walkgetattr("/foo/bar", "baz") = fid3 // Revalidate clunk(fid3) walkgetattr("/foo/bar", "baz") = fid4 // fs.Dirent.walk() => gofer.inodeOperations.Lookup getattr("/foo/bar/baz") // linux.stat() => gofer.inodeOperations.UnstableAttr() VFS2 RPCs: getattr("/") // gofer.filesystem.walkExistingLocked() walkgetattr("/", "foo") = fid1 // gofer.filesystem.stepExistingLocked() clunk(fid1) // No getattr: walkgetattr already updated metadata for permission check walkgetattr("/foo", "bar") = fid2 clunk(fid2) walkgetattr("/foo/bar", "baz") = fid3 // No clunk: fid3 used for new gofer.dentry // No getattr: walkgetattr already updated metadata for stat() - gofer.filesystem.unlinkAt() does not require instantiation of a dentry that represents the file to be deleted. Updates #898. - gofer.regularFileFD.OnClose() skips Tflushf for regular files under InteropModeExclusive, as it's nonsensical to request a remote file flush without flushing locally-buffered writes to that remote file first. - Symlink targets are cached when InteropModeShared is not in effect. - p9.QID.Path (which is already required to be unique for each file within a server, and is accordingly already synthesized from device/inode numbers in all known gofers) is used as-is for inode numbers, rather than being mapped along with attr.RDev in the client to yet another synthetic inode number. - Relevant parts of fsutil.CachingInodeOperations are inlined directly into gofer package code. This avoids having to duplicate part of its functionality in fsutil.HostMappable. PiperOrigin-RevId: 293190213
2020-02-04 19:28:36 +00:00
prefix = "FrameRef",
template = "//pkg/segment:generic_set",
types = {
"Key": "uint64",
"Range": "platform.FileRange",
"Value": "uint64",
VFS2 gofer client Updates #1198 Opening host pipes (by spinning in fdpipe) and host sockets is not yet complete, and will be done in a future CL. Major differences from VFS1 gofer client (sentry/fs/gofer), with varying levels of backportability: - "Cache policies" are replaced by InteropMode, which control the behavior of timestamps in addition to caching. Under InteropModeExclusive (analogous to cacheAll) and InteropModeWritethrough (analogous to cacheAllWritethrough), client timestamps are *not* written back to the server (it is not possible in 9P or Linux for clients to set ctime, so writing back client-authoritative timestamps results in incoherence between atime/mtime and ctime). Under InteropModeShared (analogous to cacheRemoteRevalidating), client timestamps are not used at all (remote filesystem clocks are authoritative). cacheNone is translated to InteropModeShared + new option filesystemOptions.specialRegularFiles. - Under InteropModeShared, "unstable attribute" reloading for permission checks, lookup, and revalidation are fused, which is feasible in VFS2 since gofer.filesystem controls path resolution. This results in a ~33% reduction in RPCs for filesystem operations compared to cacheRemoteRevalidating. For example, consider stat("/foo/bar/baz") where "/foo/bar/baz" fails revalidation, resulting in the instantiation of a new dentry: VFS1 RPCs: getattr("/") // fs.MountNamespace.FindLink() => fs.Inode.CheckPermission() => gofer.inodeOperations.check() => gofer.inodeOperations.UnstableAttr() walkgetattr("/", "foo") = fid1 // fs.Dirent.walk() => gofer.session.Revalidate() => gofer.cachePolicy.Revalidate() clunk(fid1) getattr("/foo") // CheckPermission walkgetattr("/foo", "bar") = fid2 // Revalidate clunk(fid2) getattr("/foo/bar") // CheckPermission walkgetattr("/foo/bar", "baz") = fid3 // Revalidate clunk(fid3) walkgetattr("/foo/bar", "baz") = fid4 // fs.Dirent.walk() => gofer.inodeOperations.Lookup getattr("/foo/bar/baz") // linux.stat() => gofer.inodeOperations.UnstableAttr() VFS2 RPCs: getattr("/") // gofer.filesystem.walkExistingLocked() walkgetattr("/", "foo") = fid1 // gofer.filesystem.stepExistingLocked() clunk(fid1) // No getattr: walkgetattr already updated metadata for permission check walkgetattr("/foo", "bar") = fid2 clunk(fid2) walkgetattr("/foo/bar", "baz") = fid3 // No clunk: fid3 used for new gofer.dentry // No getattr: walkgetattr already updated metadata for stat() - gofer.filesystem.unlinkAt() does not require instantiation of a dentry that represents the file to be deleted. Updates #898. - gofer.regularFileFD.OnClose() skips Tflushf for regular files under InteropModeExclusive, as it's nonsensical to request a remote file flush without flushing locally-buffered writes to that remote file first. - Symlink targets are cached when InteropModeShared is not in effect. - p9.QID.Path (which is already required to be unique for each file within a server, and is accordingly already synthesized from device/inode numbers in all known gofers) is used as-is for inode numbers, rather than being mapped along with attr.RDev in the client to yet another synthetic inode number. - Relevant parts of fsutil.CachingInodeOperations are inlined directly into gofer package code. This avoids having to duplicate part of its functionality in fsutil.HostMappable. PiperOrigin-RevId: 293190213
2020-02-04 19:28:36 +00:00
"Functions": "FrameRefSetFunctions",
},
)
go_template_instance(
name = "file_range_set_impl",
out = "file_range_set_impl.go",
imports = {
"memmap": "gvisor.dev/gvisor/pkg/sentry/memmap",
"platform": "gvisor.dev/gvisor/pkg/sentry/platform",
},
package = "fsutil",
prefix = "FileRange",
template = "//pkg/segment:generic_set",
types = {
"Key": "uint64",
"Range": "memmap.MappableRange",
"Value": "uint64",
"Functions": "FileRangeSetFunctions",
},
)
go_library(
name = "fsutil",
srcs = [
"dirty_set.go",
"dirty_set_impl.go",
"file.go",
"file_range_set.go",
"file_range_set_impl.go",
"frame_ref_set.go",
"frame_ref_set_impl.go",
"fsutil.go",
"host_file_mapper.go",
"host_file_mapper_state.go",
"host_file_mapper_unsafe.go",
"host_mappable.go",
"inode.go",
"inode_cached.go",
],
visibility = ["//pkg/sentry:internal"],
deps = [
"//pkg/abi/linux",
"//pkg/context",
"//pkg/log",
"//pkg/safemem",
"//pkg/sentry/arch",
"//pkg/sentry/device",
"//pkg/sentry/fs",
"//pkg/sentry/kernel/time",
"//pkg/sentry/memmap",
"//pkg/sentry/pgalloc",
"//pkg/sentry/platform",
"//pkg/sentry/socket/unix/transport",
"//pkg/sentry/usage",
"//pkg/state",
"//pkg/sync",
"//pkg/syserror",
"//pkg/usermem",
"//pkg/waiter",
],
)
go_test(
name = "fsutil_test",
size = "small",
srcs = [
"dirty_set_test.go",
"inode_cached_test.go",
],
library = ":fsutil",
deps = [
"//pkg/context",
"//pkg/safemem",
"//pkg/sentry/contexttest",
"//pkg/sentry/fs",
"//pkg/sentry/kernel/time",
"//pkg/sentry/memmap",
"//pkg/syserror",
"//pkg/usermem",
],
)