68ab60ca2d
Currently, a namespace io_opt queue limit is set by default to the
physical sector size of the namespace and to the the write optimal
size (NOWS) when the namespace reports optimal IO sizes. This causes
problems with block limits stacking in blk_stack_limits() when a
namespace block device is combined with an HDD which generally do not
report any optimal transfer size (io_opt limit is 0). The code:
/* Optimal I/O a multiple of the physical block size? */
if (t->io_opt & (t->physical_block_size - 1)) {
t->io_opt = 0;
t->misaligned = 1;
ret = -1;
}
in blk_stack_limits() results in an error return for this function when
the combined devices have different but compatible physical sector
sizes (e.g. 512B sector SSD with 4KB sector disks).
Fix this by not setting the optimal IO size queue limit if the namespace
does not report an optimal write size value.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bart van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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.