Kernel: Declare proper blocking support for StorageDevicePartitions

This commit is contained in:
Liav A 2023-06-30 11:19:21 +03:00 committed by Andrew Kaster
parent 42ed0a6c94
commit 67e028e4f4
2 changed files with 18 additions and 20 deletions

View file

@ -47,30 +47,24 @@ void StorageDevicePartition::start_request(AsyncBlockDeviceRequest& request)
ErrorOr<size_t> StorageDevicePartition::read(OpenFileDescription& fd, u64 offset, UserOrKernelBuffer& outbuf, size_t len)
{
// NOTE: The last available offset is actually just after the last addressable block.
if (offset >= (m_metadata.end_block() - m_metadata.start_block() + 1) * block_size())
return 0;
size_t nread = min(static_cast<size_t>((m_metadata.end_block() - m_metadata.start_block() + 1) - offset), len);
u64 adjust = m_metadata.start_block() * block_size();
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::read offset={}, adjust={}, len={}", fd.offset(), adjust, len);
return m_device.strong_ref()->read(fd, offset + adjust, outbuf, len);
}
bool StorageDevicePartition::can_read(OpenFileDescription const& fd, u64 offset) const
{
u64 adjust = m_metadata.start_block() * block_size();
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::can_read offset={}, adjust={}", offset, adjust);
return m_device.strong_ref()->can_read(fd, offset + adjust);
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::read offset={}, adjust={}, len={}", fd.offset(), adjust, nread);
return m_device.strong_ref()->read(fd, offset + adjust, outbuf, nread);
}
ErrorOr<size_t> StorageDevicePartition::write(OpenFileDescription& fd, u64 offset, UserOrKernelBuffer const& inbuf, size_t len)
{
// NOTE: The last available offset is actually just after the last addressable block.
if (offset >= (m_metadata.end_block() - m_metadata.start_block() + 1) * block_size())
return Error::from_errno(ENOSPC);
size_t nwrite = min(static_cast<size_t>((m_metadata.end_block() - m_metadata.start_block() + 1) - offset), len);
u64 adjust = m_metadata.start_block() * block_size();
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::write offset={}, adjust={}, len={}", offset, adjust, len);
return m_device.strong_ref()->write(fd, offset + adjust, inbuf, len);
}
bool StorageDevicePartition::can_write(OpenFileDescription const& fd, u64 offset) const
{
u64 adjust = m_metadata.start_block() * block_size();
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::can_write offset={}, adjust={}", offset, adjust);
return m_device.strong_ref()->can_write(fd, offset + adjust);
dbgln_if(OFFD_DEBUG, "StorageDevicePartition::write offset={}, adjust={}, len={}", offset, adjust, nwrite);
return m_device.strong_ref()->write(fd, offset + adjust, inbuf, nwrite);
}
StringView StorageDevicePartition::class_name() const

View file

@ -24,9 +24,13 @@ public:
// ^BlockDevice
virtual ErrorOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override;
virtual bool can_read(OpenFileDescription const&, u64) const override;
virtual ErrorOr<size_t> write(OpenFileDescription&, u64, UserOrKernelBuffer const&, size_t) override;
virtual bool can_write(OpenFileDescription const&, u64) const override;
// NOTE: Technically we need to query the underlying StorageDevice,
// but since it will always return true in both of these methods,
// we can return true here too.
virtual bool can_read(OpenFileDescription const&, u64) const override { return true; }
virtual bool can_write(OpenFileDescription const&, u64) const override { return true; }
Partition::DiskPartitionMetadata const& metadata() const;