From 81eaf151071eadbb3fba74d74324a0921c5fdb5f Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Tue, 18 Jun 2013 10:15:33 -0700 Subject: [PATCH] Register correct handlers in nvlist_alloc() The non-blocking allocation handlers in nvlist_alloc() would be mistakenly assigned if any flags other than KM_SLEEP were passed. This meant that nvlists allocated with KM_PUSHPUSH or other KM_* debug flags were effectively always using atomic allocations. While these failures were unlikely it could lead to assertions because KM_PUSHPAGE allocations in particular are guaranteed to succeed or block. They must never fail. Since the existing API does not allow us to pass allocation flags to the private allocators the cleanest thing to do is to add a KM_PUSHPAGE allocator. Signed-off-by: Brian Behlendorf Closes zfsonlinux/spl#249 --- include/sys/nvpair.h | 1 + module/nvpair/nvpair.c | 21 +++++++++++++++++---- module/nvpair/nvpair_alloc_spl.c | 20 ++++++++++++++++++++ 3 files changed, 38 insertions(+), 4 deletions(-) diff --git a/include/sys/nvpair.h b/include/sys/nvpair.h index cc399fd..c502568 100644 --- a/include/sys/nvpair.h +++ b/include/sys/nvpair.h @@ -144,6 +144,7 @@ extern nv_alloc_t *nv_alloc_nosleep; #if defined(_KERNEL) && !defined(_BOOT) extern nv_alloc_t *nv_alloc_sleep; +extern nv_alloc_t *nv_alloc_pushpage; #endif int nv_alloc_init(nv_alloc_t *, const nv_alloc_ops_t *, /* args */ ...); diff --git a/module/nvpair/nvpair.c b/module/nvpair/nvpair.c index 5c68984..36f4e4d 100644 --- a/module/nvpair/nvpair.c +++ b/module/nvpair/nvpair.c @@ -269,12 +269,25 @@ nvlist_nvflag(nvlist_t *nvl) int nvlist_alloc(nvlist_t **nvlp, uint_t nvflag, int kmflag) { + nv_alloc_t *nva = nv_alloc_nosleep; + #if defined(_KERNEL) && !defined(_BOOT) - return (nvlist_xalloc(nvlp, nvflag, - (kmflag == KM_SLEEP ? nv_alloc_sleep : nv_alloc_nosleep))); -#else - return (nvlist_xalloc(nvlp, nvflag, nv_alloc_nosleep)); + switch (kmflag) { + case KM_SLEEP: + nva = nv_alloc_sleep; + break; + case KM_PUSHPAGE: + nva = nv_alloc_pushpage; + break; + case KM_NOSLEEP: + nva = nv_alloc_nosleep; + break; + default: + return (EINVAL); + } #endif + + return (nvlist_xalloc(nvlp, nvflag, nva)); } int diff --git a/module/nvpair/nvpair_alloc_spl.c b/module/nvpair/nvpair_alloc_spl.c index 63d57a1..be6e8f0 100644 --- a/module/nvpair/nvpair_alloc_spl.c +++ b/module/nvpair/nvpair_alloc_spl.c @@ -34,6 +34,12 @@ nv_alloc_sleep_spl(nv_alloc_t *nva, size_t size) } static void * +nv_alloc_pushpage_spl(nv_alloc_t *nva, size_t size) +{ + return (kmem_alloc(size, KM_PUSHPAGE | KM_NODEBUG)); +} + +static void * nv_alloc_nosleep_spl(nv_alloc_t *nva, size_t size) { return (kmem_alloc(size, KM_NOSLEEP)); @@ -53,6 +59,14 @@ const nv_alloc_ops_t spl_sleep_ops_def = { NULL /* nv_ao_reset() */ }; +const nv_alloc_ops_t spl_pushpage_ops_def = { + NULL, /* nv_ao_init() */ + NULL, /* nv_ao_fini() */ + nv_alloc_pushpage_spl, /* nv_ao_alloc() */ + nv_free_spl, /* nv_ao_free() */ + NULL /* nv_ao_reset() */ +}; + const nv_alloc_ops_t spl_nosleep_ops_def = { NULL, /* nv_ao_init() */ NULL, /* nv_ao_fini() */ @@ -66,10 +80,16 @@ nv_alloc_t nv_alloc_sleep_def = { NULL }; +nv_alloc_t nv_alloc_pushpage_def = { + &spl_pushpage_ops_def, + NULL +}; + nv_alloc_t nv_alloc_nosleep_def = { &spl_nosleep_ops_def, NULL }; nv_alloc_t *nv_alloc_sleep = &nv_alloc_sleep_def; +nv_alloc_t *nv_alloc_pushpage = &nv_alloc_pushpage_def; nv_alloc_t *nv_alloc_nosleep = &nv_alloc_nosleep_def; -- 1.8.3.1