Kernel/FUSE: Allow buffering multiple requests

It can be possible for a request to be blocked on another request, so
this patch allows us to send more requests even when a request is
already pending.
This commit is contained in:
implicitfield 2024-05-11 08:08:30 +04:00 committed by Andrew Kaster
commit ef766b0b5f
Notes: sideshowbarker 2024-07-17 01:23:08 +09:00
3 changed files with 70 additions and 80 deletions

View file

@ -24,39 +24,38 @@ UNMAP_AFTER_INIT FUSEDevice::FUSEDevice()
UNMAP_AFTER_INIT FUSEDevice::~FUSEDevice() = default; UNMAP_AFTER_INIT FUSEDevice::~FUSEDevice() = default;
ErrorOr<void> FUSEDevice::initialize_instance(OpenFileDescription const& fd) ErrorOr<void> FUSEDevice::initialize_instance(OpenFileDescription const& description)
{ {
return m_instances.with([&](auto& instances) -> ErrorOr<void> { return m_instances.with([&](auto& instances) -> ErrorOr<void> {
for (auto const& instance : instances) VERIFY(!instances.contains(&description));
VERIFY(instance.fd != &fd); TRY(instances.try_set(&description, {}));
TRY(instances.try_append({
&fd,
TRY(KBuffer::try_create_with_size("FUSE: Pending request buffer"sv, 0x21000)),
TRY(KBuffer::try_create_with_size("FUSE: Response buffer"sv, 0x21000)),
}));
return {}; return {};
}); });
} }
bool FUSEDevice::can_read(OpenFileDescription const& fd, u64) const bool FUSEDevice::can_read(OpenFileDescription const& description, u64) const
{ {
bool drop = m_closing_instances.with([&](auto& closing_instances) {
auto iterator = closing_instances.find(&description);
return iterator != closing_instances.end();
});
if (drop)
return true;
return m_instances.with([&](auto& instances) { return m_instances.with([&](auto& instances) {
Optional<size_t> instance_index = {}; auto instance_iterator = instances.find(&description);
for (size_t i = 0; i < instances.size(); ++i) { if (instance_iterator == instances.end()) {
if (instances[i].fd == &fd) {
instance_index = i;
break;
}
}
if (!instance_index.has_value()) {
VERIFY(instances.is_empty()); VERIFY(instances.is_empty());
return false; return false;
} }
auto& instance = instances[instance_index.value()]; auto const& requests_for_instance = (*instance_iterator).value;
return instance.buffer_ready || instance.drop_request; for (auto const& request : requests_for_instance.in_reverse()) {
if (request.buffer_ready)
return true;
}
return false;
}); });
} }
@ -65,56 +64,49 @@ bool FUSEDevice::can_write(OpenFileDescription const&, u64) const
return true; return true;
} }
ErrorOr<size_t> FUSEDevice::read(OpenFileDescription& fd, u64, UserOrKernelBuffer& buffer, size_t size) ErrorOr<size_t> FUSEDevice::read(OpenFileDescription& description, u64, UserOrKernelBuffer& buffer, size_t size)
{ {
TRY(m_closing_instances.with([&](auto& closing_instances) -> ErrorOr<void> {
bool removed = closing_instances.remove_first_matching([&](auto const* closing_description) { return closing_description == &description; });
if (removed)
return Error::from_errno(ENODEV);
return {};
}));
if (size < 0x21000)
return Error::from_errno(EIO);
return m_instances.with([&](auto& instances) -> ErrorOr<size_t> { return m_instances.with([&](auto& instances) -> ErrorOr<size_t> {
Optional<size_t> instance_index = {}; auto instance_iterator = instances.find(&description);
for (size_t i = 0; i < instances.size(); ++i) { if (instance_iterator == instances.end())
if (instances[i].fd == &fd) {
instance_index = i;
break;
}
}
if (!instance_index.has_value())
return Error::from_errno(ENODEV); return Error::from_errno(ENODEV);
auto& instance = instances[instance_index.value()]; auto& requests_for_instance = (*instance_iterator).value;
if (instance.drop_request) { for (auto& request : requests_for_instance.in_reverse()) {
instance.drop_request = false; if (!request.buffer_ready)
continue;
instances.remove(instance_index.value()); TRY(buffer.write(request.pending_request->bytes()));
return Error::from_errno(ENODEV); request.buffer_ready = false;
return request.pending_request->size();
} }
if (size < 0x21000) return Error::from_errno(ENOENT);
return Error::from_errno(EIO);
if (!instance.buffer_ready)
return Error::from_errno(ENOENT);
TRY(buffer.write(instance.pending_request->bytes()));
instance.buffer_ready = false;
return instance.pending_request->size();
}); });
} }
ErrorOr<size_t> FUSEDevice::write(OpenFileDescription& description, u64, UserOrKernelBuffer const& buffer, size_t size) ErrorOr<size_t> FUSEDevice::write(OpenFileDescription& description, u64, UserOrKernelBuffer const& buffer, size_t size)
{ {
return m_instances.with([&](auto& instances) -> ErrorOr<size_t> { return m_instances.with([&](auto& instances) -> ErrorOr<size_t> {
Optional<size_t> instance_index = {}; auto instance_iterator = instances.find(&description);
for (size_t i = 0; i < instances.size(); ++i) {
if (instances[i].fd == &description) {
instance_index = i;
break;
}
}
if (!instance_index.has_value()) if (instance_iterator == instances.end())
return Error::from_errno(ENODEV); return Error::from_errno(ENODEV);
auto& instance = instances[instance_index.value()]; auto& requests_for_instance = (*instance_iterator).value;
auto& instance = requests_for_instance.last();
if (instance.expecting_header) { if (instance.expecting_header) {
memset(instance.response->data(), 0, instance.response->size()); memset(instance.response->data(), 0, instance.response->size());
@ -149,18 +141,18 @@ ErrorOr<size_t> FUSEDevice::write(OpenFileDescription& description, u64, UserOrK
ErrorOr<NonnullOwnPtr<KBuffer>> FUSEDevice::send_request_and_wait_for_a_reply(OpenFileDescription const& description, Bytes bytes) ErrorOr<NonnullOwnPtr<KBuffer>> FUSEDevice::send_request_and_wait_for_a_reply(OpenFileDescription const& description, Bytes bytes)
{ {
return m_instances.with([&](auto& instances) -> ErrorOr<NonnullOwnPtr<KBuffer>> { return m_instances.with([&](auto& instances) -> ErrorOr<NonnullOwnPtr<KBuffer>> {
Optional<size_t> instance_index = {}; auto instance_iterator = instances.find(&description);
for (size_t i = 0; i < instances.size(); ++i) { VERIFY(instance_iterator != instances.end());
if (instances[i].fd == &description) { auto& requests_for_instance = (*instance_iterator).value;
instance_index = i;
break;
}
}
VERIFY(instance_index.has_value()); TRY(requests_for_instance.try_append({
auto& instance = instances[instance_index.value()]; &description,
TRY(KBuffer::try_create_with_size("FUSE: Pending request buffer"sv, 0x21000)),
TRY(KBuffer::try_create_with_size("FUSE: Response buffer"sv, 0x21000)),
}));
VERIFY(!instance.drop_request); size_t instance_index = requests_for_instance.size() - 1;
auto& instance = requests_for_instance.last();
VERIFY(bytes.size() <= 0x21000); VERIFY(bytes.size() <= 0x21000);
memset(instance.pending_request->data(), 0, instance.pending_request->size()); memset(instance.pending_request->data(), 0, instance.pending_request->size());
@ -172,7 +164,7 @@ ErrorOr<NonnullOwnPtr<KBuffer>> FUSEDevice::send_request_and_wait_for_a_reply(Op
(void)Thread::current()->sleep(Duration::from_microseconds(100)); (void)Thread::current()->sleep(Duration::from_microseconds(100));
auto result = KBuffer::try_create_with_bytes("FUSEDevice: Response"sv, instance.response->bytes()); auto result = KBuffer::try_create_with_bytes("FUSEDevice: Response"sv, instance.response->bytes());
instance.response_ready = false; requests_for_instance.remove(instance_index);
return result; return result;
}); });
@ -181,15 +173,11 @@ ErrorOr<NonnullOwnPtr<KBuffer>> FUSEDevice::send_request_and_wait_for_a_reply(Op
void FUSEDevice::shutdown_for_description(OpenFileDescription const& description) void FUSEDevice::shutdown_for_description(OpenFileDescription const& description)
{ {
m_instances.with([&](auto& instances) { m_instances.with([&](auto& instances) {
Optional<size_t> instance_index = {}; VERIFY(instances.remove(&description));
for (size_t i = 0; i < instances.size(); ++i) { });
if (instances[i].fd == &description) {
instance_index = i; m_closing_instances.with([&](auto& closing_instances) {
break; closing_instances.append(&description);
}
}
VERIFY(instance_index.has_value());
instances[instance_index.value()].drop_request = true;
}); });
evaluate_block_conditions(); evaluate_block_conditions();

View file

@ -6,7 +6,7 @@
#pragma once #pragma once
#include <AK/Atomic.h> #include <AK/HashMap.h>
#include <Kernel/Devices/CharacterDevice.h> #include <Kernel/Devices/CharacterDevice.h>
#include <Kernel/Locking/Mutex.h> #include <Kernel/Locking/Mutex.h>
#include <Kernel/Locking/SpinlockProtected.h> #include <Kernel/Locking/SpinlockProtected.h>
@ -17,7 +17,6 @@ struct FUSEInstance {
OpenFileDescription const* fd = nullptr; OpenFileDescription const* fd = nullptr;
NonnullOwnPtr<KBuffer> pending_request; NonnullOwnPtr<KBuffer> pending_request;
NonnullOwnPtr<KBuffer> response; NonnullOwnPtr<KBuffer> response;
bool drop_request = false;
bool buffer_ready = false; bool buffer_ready = false;
bool response_ready = false; bool response_ready = false;
bool expecting_header = true; bool expecting_header = true;
@ -47,7 +46,8 @@ private:
virtual bool can_write(OpenFileDescription const&, u64) const override; virtual bool can_write(OpenFileDescription const&, u64) const override;
virtual StringView class_name() const override { return "FUSEDevice"sv; } virtual StringView class_name() const override { return "FUSEDevice"sv; }
SpinlockProtected<Vector<FUSEInstance>, LockRank::None> m_instances; SpinlockProtected<HashMap<OpenFileDescription const*, Vector<FUSEInstance>>, LockRank::None> m_instances;
SpinlockProtected<Vector<OpenFileDescription const*>, LockRank::None> m_closing_instances;
}; };
} }

View file

@ -6,6 +6,7 @@
#pragma once #pragma once
#include <AK/Atomic.h>
#include <Kernel/FileSystem/FUSE/Definitions.h> #include <Kernel/FileSystem/FUSE/Definitions.h>
#include <Kernel/FileSystem/OpenFileDescription.h> #include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Library/KBuffer.h> #include <Kernel/Library/KBuffer.h>
@ -62,10 +63,11 @@ public:
if (!m_initialized) if (!m_initialized)
TRY(handle_init()); TRY(handle_init());
auto request = TRY(create_request(opcode, nodeid, m_unique, request_body)); u32 unique = m_unique++;
auto request = TRY(create_request(opcode, nodeid, unique, request_body));
auto response = TRY(device->send_request_and_wait_for_a_reply(m_description, request->bytes())); auto response = TRY(device->send_request_and_wait_for_a_reply(m_description, request->bytes()));
if (validate_response(*response, m_unique++).is_error()) if (validate_response(*response, unique).is_error())
return Error::from_errno(EIO); return Error::from_errno(EIO);
return response; return response;
@ -134,7 +136,7 @@ private:
NonnullRefPtr<OpenFileDescription> m_description; NonnullRefPtr<OpenFileDescription> m_description;
bool m_initialized { false }; bool m_initialized { false };
u32 m_unique { 0 }; Atomic<u32> m_unique { 0 };
u32 m_major { 0 }; u32 m_major { 0 };
u32 m_minor { 0 }; u32 m_minor { 0 };