Rob Norris f237b8e2a4 vdev_disk: try harder to ensure IO alignment rules ... It seems out our notion of "properly" aligned IO was incomplete. In particular, dm-crypt does its own splitting, and assumes that a logical block will never cross an order-0 page boundary (ie, the physical page size, not compound size). This effectively means that it needs to be possible to split a BIO at any page or block size boundary and have it work correctly. This updates the alignment check function to enforce these rules (to the extent possible). Our response to misaligned data is to make some new allocation that is properly aligned, and copy the data into it. It turns out that linearising (via abd_borrow_buf()) is not enough, because we allocate eg 4K blocks from a general purpose slab, and so may receive (or already have) a 4K block that crosses pages. So instead, we allocate a new ABD, which is guaranteed to be aligned properly to block sizes, and then copy everything into it, and back out on the way back. Sponsored-by: Klara, Inc. Sponsored-by: Wasabi Technology, Inc. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Alexander Motin <mav@FreeBSD.org> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Signed-off-by: Rob Norris <rob.norris@klarasystems.com> Closes #16687 #16631 #15646 #15533 #14533 (cherry picked from commit 63bafe60ec741c269d29e26b192a8a5c4f6acf92)		2024-11-06 10:06:30 -08:00
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spl	Linux 6.11: avoid passing "end" sentinel to register_sysctl()	2024-08-22 15:42:14 -07:00
zfs	vdev_disk: try harder to ensure IO alignment rules	2024-11-06 10:06:30 -08:00