lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 25 Sep 2018 15:13:29 +0800 From: Huang Ying <ying.huang@...el.com> To: Andrew Morton <akpm@...ux-foundation.org> Cc: linux-mm@...ck.org, linux-kernel@...r.kernel.org, Huang Ying <ying.huang@...el.com>, "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>, Andrea Arcangeli <aarcange@...hat.com>, Michal Hocko <mhocko@...nel.org>, Johannes Weiner <hannes@...xchg.org>, Shaohua Li <shli@...nel.org>, Hugh Dickins <hughd@...gle.com>, Minchan Kim <minchan@...nel.org>, Rik van Riel <riel@...hat.com>, Dave Hansen <dave.hansen@...ux.intel.com>, Naoya Horiguchi <n-horiguchi@...jp.nec.com>, Zi Yan <zi.yan@...rutgers.edu>, Daniel Jordan <daniel.m.jordan@...cle.com> Subject: [PATCH -V5 RESEND 02/21] swap: Add __swap_duplicate_locked() The part of __swap_duplicate() with lock held is separated into a new function __swap_duplicate_locked(). Because we will add more logic about the PMD swap mapping into __swap_duplicate() and keep the most PTE swap mapping related logic in __swap_duplicate_locked(). Just mechanical code refactoring, there is no any functional change in this patch. Signed-off-by: "Huang, Ying" <ying.huang@...el.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com> Cc: Andrea Arcangeli <aarcange@...hat.com> Cc: Michal Hocko <mhocko@...nel.org> Cc: Johannes Weiner <hannes@...xchg.org> Cc: Shaohua Li <shli@...nel.org> Cc: Hugh Dickins <hughd@...gle.com> Cc: Minchan Kim <minchan@...nel.org> Cc: Rik van Riel <riel@...hat.com> Cc: Dave Hansen <dave.hansen@...ux.intel.com> Cc: Naoya Horiguchi <n-horiguchi@...jp.nec.com> Cc: Zi Yan <zi.yan@...rutgers.edu> Cc: Daniel Jordan <daniel.m.jordan@...cle.com> --- mm/swapfile.c | 63 +++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 35 insertions(+), 28 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index 97a1bd1a7c9a..6a570ef00fa7 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3436,32 +3436,12 @@ void si_swapinfo(struct sysinfo *val) spin_unlock(&swap_lock); } -/* - * Verify that a swap entry is valid and increment its swap map count. - * - * Returns error code in following case. - * - success -> 0 - * - swp_entry is invalid -> EINVAL - * - swp_entry is migration entry -> EINVAL - * - swap-cache reference is requested but there is already one. -> EEXIST - * - swap-cache reference is requested but the entry is not used. -> ENOENT - * - swap-mapped reference requested but needs continued swap count. -> ENOMEM - */ -static int __swap_duplicate(swp_entry_t entry, unsigned char usage) +static int __swap_duplicate_locked(struct swap_info_struct *p, + unsigned long offset, unsigned char usage) { - struct swap_info_struct *p; - struct swap_cluster_info *ci; - unsigned long offset; unsigned char count; unsigned char has_cache; - int err = -EINVAL; - - p = get_swap_device(entry); - if (!p) - goto out; - - offset = swp_offset(entry); - ci = lock_cluster_or_swap_info(p, offset); + int err = 0; count = p->swap_map[offset]; @@ -3471,12 +3451,11 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) */ if (unlikely(swap_count(count) == SWAP_MAP_BAD)) { err = -ENOENT; - goto unlock_out; + goto out; } has_cache = count & SWAP_HAS_CACHE; count &= ~SWAP_HAS_CACHE; - err = 0; if (usage == SWAP_HAS_CACHE) { @@ -3503,11 +3482,39 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) p->swap_map[offset] = count | has_cache; -unlock_out: +out: + return err; +} + +/* + * Verify that a swap entry is valid and increment its swap map count. + * + * Returns error code in following case. + * - success -> 0 + * - swp_entry is invalid -> EINVAL + * - swp_entry is migration entry -> EINVAL + * - swap-cache reference is requested but there is already one. -> EEXIST + * - swap-cache reference is requested but the entry is not used. -> ENOENT + * - swap-mapped reference requested but needs continued swap count. -> ENOMEM + */ +static int __swap_duplicate(swp_entry_t entry, unsigned char usage) +{ + struct swap_info_struct *p; + struct swap_cluster_info *ci; + unsigned long offset; + int err = -EINVAL; + + p = get_swap_device(entry); + if (!p) + goto out; + + offset = swp_offset(entry); + ci = lock_cluster_or_swap_info(p, offset); + err = __swap_duplicate_locked(p, offset, usage); unlock_cluster_or_swap_info(p, ci); + + put_swap_device(p); out: - if (p) - put_swap_device(p); return err; } -- 2.16.4
Powered by blists - more mailing lists