btrfsic_read_block() (which calls kmap()) and
btrfsic_release_block_ctx() (which calls kunmap()) are always called
within a single thread of execution.
Therefore the mappings created within these calls can be a thread local
mapping.
Convert the kmap() of bloc_ctx->pagev to kmap_local_page(). Luckily the
unmap loops backwards through the array pointer so no adjustment needs
to be made to the unmapping order.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
BUG_ON(!block_ctx->pagev);
num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >>
PAGE_SHIFT;
+ /* Pages must be unmapped in reverse order */
while (num_pages > 0) {
num_pages--;
if (block_ctx->datav[num_pages]) {
- kunmap(block_ctx->pagev[num_pages]);
+ kunmap_local(block_ctx->datav[num_pages]);
block_ctx->datav[num_pages] = NULL;
}
if (block_ctx->pagev[num_pages]) {
i = j;
}
for (i = 0; i < num_pages; i++)
- block_ctx->datav[i] = kmap(block_ctx->pagev[i]);
+ block_ctx->datav[i] = kmap_local_page(block_ctx->pagev[i]);
return block_ctx->len;
}