misc: xilinx-sdfec: improve get_user_pages_fast() error handling

This fixes the case of get_user_pages_fast() returning a -errno.
The result needs to be stored in a signed integer. And for safe
signed/unsigned comparisons, it's best to keep everything signed.
And get_user_pages_fast() also expects a signed value for number
of pages to pin.

Therefore, change most relevant variables, from u32 to int. Leave
"n" unsigned, for convenience in checking for overflow. And provide
a WARN_ON_ONCE() and early return, if overflow occurs.

Also, as long as we're tidying up: rename the page array from page,
to pages, in order to match the conventions used in most other call
sites.

Fixes: 20ec628e8007e ("misc: xilinx_sdfec: Add ability to configure LDPC")
Cc: Derek Kiernan <[email protected]>
Cc: Dragan Cvetic <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: [email protected]
Signed-off-by: John Hubbard <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

0 files changed, 0 insertions, 0 deletions