bbd876adb8
Once the dma request is passed to the DMA engine, the DMA subsystem would hold a pointer to this structure and could call the completion callback after do_dma_request() has timed out. The current code deals with this by putting timed out SYNC requests to a pending list and freeing them later, when the mport cdev device is released. This still does not guarantee that the DMA subsystem is really done with those transfers, so in theory dma_xfer_callback/dma_req_free could be called after mport_cdev_release_dma and could potentially access already freed memory. This patch simplifies the current handling by using a kref in the mport dma request structure, so that it gets freed only when nobody uses it anymore. This also simplifies the code a bit, as FAF transfers are now handled in the same way as SYNC and ASYNC transfers. There is no need anymore for the pending list and for the dma workqueue which was used in case of FAF transfers, so we remove them both. Link: http://lkml.kernel.org/r/20180405203342.GA16191@nokia.com Signed-off-by: Ioan Nicu <ioan.nicu.ext@nokia.com> Acked-by: Alexandre Bounine <alex.bou9@gmail.com> Cc: Barry Wood <barry.wood@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Frank Kunz <frank.kunz@nokia.com> Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.