On 12/14/24 04:10, Luis Chamberlain wrote:
Provide a helper to iterate on buffer heads on a folio. We do this as a preliminary step so to make the subsequent changes easier to read. Right now we use an array on stack to loop over all buffer heads in a folio of size MAX_BUF_PER_PAGE, however on CPUs where the system page size is quite larger like Hexagon with 256 KiB page size support this can mean the kernel can end up spewing spews stack growth warnings. To be able to break this down into smaller array chunks add support for processing smaller array chunks of buffer heads at a time. The used array size is not changed yet, that will be done in a subsequent patch, this just adds the iterator support and logic. While at it clarify the booleans used on bh_read_batch_async() and how they are only valid in consideration when we've processed all buffer-heads of a folio, that is when we're on the last buffer head in a folio: * bh_folio_reads * unmapped Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> --- fs/buffer.c | 130 +++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 94 insertions(+), 36 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich