7ed2ed2db2
Code used to create a ddw property that was previously scattered in enable_ddw() is now gathered in ddw_property_create(), which deals with allocation and filling the property, letting it ready for of_property_add(), which now occurs in sequence. This created an opportunity to reorganize the second part of enable_ddw(): Without this patch enable_ddw() does, in order: kzalloc() property & members, create_ddw(), fill ddwprop inside property, ddw_list_new_entry(), do tce_setrange_multi_pSeriesLP_walk in all memory, of_add_property(), and list_add(). With this patch enable_ddw() does, in order: create_ddw(), ddw_property_create(), of_add_property(), ddw_list_new_entry(), do tce_setrange_multi_pSeriesLP_walk in all memory, and list_add(). This change requires of_remove_property() in case anything fails after of_add_property(), but we get to do tce_setrange_multi_pSeriesLP_walk in all memory, which looks the most expensive operation, only if everything else succeeds. Also, the error path got remove_ddw() replaced by a new helper __remove_dma_window(), which only removes the new DDW with an rtas-call. For this, a new helper clean_dma_window() was needed to clean anything that could left if walk_system_ram_range() fails. Signed-off-by: Leonardo Bras <leobras.c@gmail.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210817063929.38701-7-leobras.c@gmail.com
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.
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.