Commit Graph

17 Commits

Author SHA1 Message Date
Norman Feske
04cf6ea3ab os: avoid implicit conversions
Issue #23
2021-12-17 15:04:45 +01:00
Norman Feske
0339318572 platform_session: cache arg for alloc_dma_buffer
This patch extends the 'Platform_session::alloc_dma_buffer' interface
with a 'Cache' argument that corresponds to the argument accepted by
'Ram_allocator::alloc', which is used by the platform driver under the
hood.

Since the x86 platform driver used to be hardwired to allocate DMA
buffers as UNCACHED, I adjusted all drivers by specifying the UNCACHED
argument. Right now, this is needed as a hint for core to steer the
allocation of I/O page tables. Once we eliminate the need for such hints
(by introducing an explicit 'Region_map::attach_dma' operation), we can
revisit the drivers individually because cached DMA buffers should
generally be fine on the x86 architecture.

Issue #2243
2021-04-20 12:10:57 +02:00
Josef Söntgen
c53be5a3fb os: omit size check on payloadless Block packets
The check is already performed in 'packet_valid' where the conditions
for payloadless packets are already considered.

Fixes #3660.
2020-02-27 14:46:57 +01:00
Norman Feske
593e971121 block_session: SYNC and TRIM as async operations
This patch removes the blocking Block::Session::sync RPC function and
adds the asynchronous operations SYNC and TRIM to the block session's
packet-stream interface.

Even though the patch adjusts all block components to the interface
change, the components keep the former blocking handling of sync
internally for now because of the design of the 'Block::Driver'
interface. This old interface is not worth changing. We should instead
migrate the block servers step by step to the new
'Block::Request_stream' API.

Fixes #3274
2019-05-06 16:15:24 +02:00
Norman Feske
bbe3ee8dc5 block_session: server-defined payload alignment
This patch replaces the formerly fixed 2 KiB data alignment within the
packet-stream buffer by a server-defined alignment. This has two
benefits.

First, when using block servers that provide small block sizes like 512
bytes, we avoid fragmenting the packet-stream buffer, which occurs when
aligning 512-byte requests at 2 KiB boundaries. This reduces meta data
costs for the packet-stream allocator and also allows fitting more
requests into the buffer.

Second, block drivers with alignment constraints dictated by the
hardware can now pass those constraints to the client, thereby easing
the use of zero-copy DMA directly into the packet stream.

The alignment is determined by the Block::Session_client at construction
time and applied by the Block::Session_client::alloc_packet method.
Block-session clients should always use this method, not the 'alloc_packet'
method of the packet stream (tx source) directly. The latter merely
applies a default alignment of 2 KiB.

At the server side, the alignment is automatically checked by
block/component.h (old API) and block/request_stream.h (new API).

Issue #3274
2019-05-03 13:53:12 +02:00
Norman Feske
2208220c12 block session: remove Block::Session::Operations
This patch modernizes the 'Block::Session::info' interface. Instead of
using out parameters, the 'init' RPC function returns a compound 'Info'
object now. The rather complicated 'Operations' struct is replaced by
a 'writeable' attribute in the 'Info' object.

Fixes #3275
2019-05-03 13:53:12 +02:00
Norman Feske
b3727a9b46 Add missing override annotations
Issue #3159
2019-02-19 11:12:11 +01:00
Emery Hemingway
a2bdcc68c2 Throw exception for invalid packets at packet streams
Some application code is dereferencing the pointer returned by
'packet_content' at packet streams without checking that it is valid.
Throw an exception rather than return a null pointer, except for
zero-length packets, which have somewhat implicit invalid content and
that we believe to be properly handled in all current cases.

The client-side of a packet stream cannot take corrective action if the
server-side is sending packets with invalid content, but the servers
that provide packet streams should catch this exception to detect
misbehaving clients.

Ref #3059
2018-11-29 11:54:29 +01:00
Norman Feske
eba9c15746 Follow practices suggested by "Effective C++"
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:

* A class with virtual functions can no longer publicly inherit base
  classed without a vtable. The inherited object may either be moved
  to a member variable, or inherited privately. The latter would be
  used for classes that inherit 'List::Element' or 'Avl_node'. In order
  to enable the 'List' and 'Avl_tree' to access the meta data, the
  'List' must become a friend.

* Instead of adding a virtual destructor to abstract base classes,
  we inherit the new 'Interface' class, which contains a virtual
  destructor. This way, single-line abstract base classes can stay
  as compact as they are now. The 'Interface' utility resides in
  base/include/util/interface.h.

* With the new warnings enabled, all member variables must be explicitly
  initialized. Basic types may be initialized with '='. All other types
  are initialized with braces '{ ... }' or as class initializers. If
  basic types and non-basic types appear in a row, it is nice to only
  use the brace syntax (also for basic types) and align the braces.

* If a class contains pointers as members, it must now also provide a
  copy constructor and assignment operator. In the most cases, one
  would make them private, effectively disallowing the objects to be
  copied. Unfortunately, this warning cannot be fixed be inheriting
  our existing 'Noncopyable' class (the compiler fails to detect that
  the inheriting class cannot be copied and still gives the error).
  For now, we have to manually add declarations for both the copy
  constructor and assignment operator as private class members. Those
  declarations should be prepended with a comment like this:

        /*
         * Noncopyable
         */
        Thread(Thread const &);
        Thread &operator = (Thread const &);

  In the future, we should revisit these places and try to replace
  the pointers with references. In the presence of at least one
  reference member, the compiler would no longer implicitly generate
  a copy constructor. So we could remove the manual declaration.

Issue #465
2018-01-17 12:14:35 +01:00
Emery Hemingway
1fce8d0d74 default ahci_drv and part_blk Block sessions to read-only
Add a "writeable" policy option to the ahci_drv and part_blk Block
servers and default from writeable to ready-only. Should a policy
permit write acesss the session request argument "writeable" may still
downgrade a session to ready-only.

Fix #2469
2017-08-28 16:49:51 +02:00
Norman Feske
6609aafb05 Replace Quota_exceeded by Insufficient_ram_quota
This patch replaces the 'Parent::Quota_exceeded',
'Service::Quota_exceeded', and 'Root::Quota_exceeded' exceptions
by the single 'Insufficient_ram_quota' exception type.

Furthermore, the 'Parent' interface distinguished now between
'Out_of_ram' (the child's RAM is exhausted) from
'Insufficient_ram_quota' (the child's RAM donation does not suffice to
establish the session).

This eliminates ambiguities and removes the need to convert exception
types along the path of the session creation.

Issue #2398
2017-05-31 13:16:05 +02:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Christian Prochaska
344f6f9e53 os/include/block: API transition (fix 'deprecated' warnings)
...and adaptation of the users of 'Block::Driver', 'Block::Root' and
'Block::Session_component' to the modified interface.

Issue #1987
2017-01-20 16:46:57 +01:00
Norman Feske
17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00
Stefan Kalkowski
7f8f0f50ea block layer: transition to new API
Ref #1987
Fix #2058
2016-08-29 17:23:20 +02:00
Sebastian Sumpf
4994616346 os: packets without playload in packet stream
issue #1988
2016-06-04 13:45:26 +02:00
Norman Feske
ca971bbfd8 Move repositories to 'repos/' subdirectory
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.

Issue #1082
2014-05-14 16:08:00 +02:00