mm: frontswap: core frontswap functionality

This patch, 3of4, provides the core frontswap code that interfaces between
the hooks in the swap subsystem and a frontswap backend via frontswap_ops.

---
New file added: mm/frontswap.c

[v14: add support for writethrough, per suggestion by [email protected]]
[v11: [email protected]: s/puts/failed_puts/]
[v10: [email protected]: fix debugfs calls on 32-bit]
[v9: [email protected]: change "flush" to "invalidate", part 1]
[v9: [email protected]: mark some statics __read_mostly]
[v9: [email protected]: add clarifying comments]
[v9: [email protected]: no need to loop repeating try_to_unuse]
[v9: [email protected]: remove superfluous check for NULL]
[v8: rebase to 3.0-rc4]
[v8: [email protected]: add comment to clarify find_next_to_unuse]
[v7: rebase to 3.0-rc3]
[v7: [email protected]: use new static inlines, no-ops if not config'd]
[v6: rebase to 3.1-rc1]
[v6: [email protected]: use vzalloc]
[v6: [email protected]: fix null pointer deref if vzalloc fails]
[v6: [email protected]: various checks and code clarifications/comments]
[v4: rebase to 2.6.39]
Signed-off-by: Dan Magenheimer <[email protected]>
Acked-by: Jan Beulich <[email protected]>
Acked-by: Seth Jennings <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Nitin Gupta <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: Rik Riel <[email protected]>
Cc: Andrew Morton <[email protected]>
[v12: Squashed s/flush/invalidate/ in]
[v15: A bit of cleanup and seperate DEBUGFS]
Signed-off-by: Konrad Wilk <[email protected]>

0 files changed, 0 insertions, 0 deletions