[PATCH 13/24] HWPOISON: introduce struct hwpoison_control
From: Wu Fengguang
Date: Tue Dec 01 2009 - 23:41:34 EST
This allows passing around more parameters and states.
No behavior change.
CC: Andi Kleen <andi@xxxxxxxxxxxxxx>
Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx>
---
mm/memory-failure.c | 108 +++++++++++++++++++++++++-----------------
1 file changed, 65 insertions(+), 43 deletions(-)
--- linux-mm.orig/mm/memory-failure.c 2009-11-30 20:33:58.000000000 +0800
+++ linux-mm/mm/memory-failure.c 2009-11-30 20:35:49.000000000 +0800
@@ -313,20 +313,27 @@ static void collect_procs(struct page *p
* Error handlers for various types of pages.
*/
-enum outcome {
+enum hwpoison_result {
FAILED, /* Error handling failed */
DELAYED, /* Will be handled later */
IGNORED, /* Error safely ignored */
RECOVERED, /* Successfully recovered */
};
-static const char *action_name[] = {
+static const char *hwpoison_result_name[] = {
[FAILED] = "Failed",
[DELAYED] = "Delayed",
[IGNORED] = "Ignored",
[RECOVERED] = "Recovered",
};
+struct hwpoison_control {
+ unsigned long pfn;
+ struct page *p; /* raw corrupted page */
+ struct page *page; /* compound page head */
+ int result;
+};
+
/*
* XXX: It is possible that a page is isolated from LRU cache,
* and then kept in swap cache or failed to remove from page cache.
@@ -356,7 +363,7 @@ static int delete_from_lru_cache(struct
* Do nothing, try to be lucky and not touch this instead. For a few cases we
* could be more sophisticated.
*/
-static int me_kernel(struct page *p, unsigned long pfn)
+static int me_kernel(struct hwpoison_control *hpc)
{
return DELAYED;
}
@@ -364,28 +371,30 @@ static int me_kernel(struct page *p, uns
/*
* Already poisoned page.
*/
-static int me_ignore(struct page *p, unsigned long pfn)
+static int me_ignore(struct hwpoison_control *hpc)
{
+ printk(KERN_ERR "MCE %#lx: Unknown page state\n", hpc->pfn);
return IGNORED;
}
/*
* Page in unknown state. Do nothing.
*/
-static int me_unknown(struct page *p, unsigned long pfn)
+static int me_unknown(struct hwpoison_control *hpc)
{
- printk(KERN_ERR "MCE %#lx: Unknown page state\n", pfn);
+ printk(KERN_ERR "MCE %#lx: Unknown page state\n", hpc->pfn);
return FAILED;
}
/*
* Clean (or cleaned) page cache page.
*/
-static int me_pagecache_clean(struct page *p, unsigned long pfn)
+static int me_pagecache_clean(struct hwpoison_control *hpc)
{
int err;
int ret = FAILED;
struct address_space *mapping;
+ struct page *p = hpc->page;
delete_from_lru_cache(p);
@@ -420,10 +429,11 @@ static int me_pagecache_clean(struct pag
err = mapping->a_ops->error_remove_page(mapping, p);
if (err != 0) {
printk(KERN_INFO "MCE %#lx: Failed to punch page: %d\n",
- pfn, err);
+ hpc->pfn, err);
} else if (page_has_private(p) &&
!try_to_release_page(p, GFP_NOIO)) {
- pr_debug("MCE %#lx: failed to release buffers\n", pfn);
+ pr_debug("MCE %#lx: failed to release buffers\n",
+ hpc->pfn);
} else {
ret = RECOVERED;
}
@@ -436,7 +446,7 @@ static int me_pagecache_clean(struct pag
ret = RECOVERED;
else
printk(KERN_INFO "MCE %#lx: Failed to invalidate\n",
- pfn);
+ hpc->pfn);
}
return ret;
}
@@ -446,11 +456,11 @@ static int me_pagecache_clean(struct pag
* Issues: when the error hit a hole page the error is not properly
* propagated.
*/
-static int me_pagecache_dirty(struct page *p, unsigned long pfn)
+static int me_pagecache_dirty(struct hwpoison_control *hpc)
{
- struct address_space *mapping = page_mapping(p);
+ struct address_space *mapping = page_mapping(hpc->page);
- SetPageError(p);
+ SetPageError(hpc->page);
/* TBD: print more information about the file. */
if (mapping) {
/*
@@ -490,7 +500,7 @@ static int me_pagecache_dirty(struct pag
mapping_set_error(mapping, EIO);
}
- return me_pagecache_clean(p, pfn);
+ return me_pagecache_clean(hpc);
}
/*
@@ -512,8 +522,9 @@ static int me_pagecache_dirty(struct pag
* Clean swap cache pages can be directly isolated. A later page fault will
* bring in the known good data from disk.
*/
-static int me_swapcache_dirty(struct page *p, unsigned long pfn)
+static int me_swapcache_dirty(struct hwpoison_control *hpc)
{
+ struct page *p = hpc->page;
ClearPageDirty(p);
/* Trigger EIO in shmem: */
ClearPageUptodate(p);
@@ -524,8 +535,10 @@ static int me_swapcache_dirty(struct pag
return FAILED;
}
-static int me_swapcache_clean(struct page *p, unsigned long pfn)
+static int me_swapcache_clean(struct hwpoison_control *hpc)
{
+ struct page *p = hpc->page;
+
delete_from_swap_cache(p);
if (!delete_from_lru_cache(p))
@@ -545,7 +558,7 @@ static int me_swapcache_clean(struct pag
* Should handle free huge pages and dequeue them too, but this needs to
* handle huge page accounting correctly.
*/
-static int me_huge_page(struct page *p, unsigned long pfn)
+static int me_huge_page(struct hwpoison_control *hpc)
{
return FAILED;
}
@@ -581,7 +594,7 @@ static struct page_state {
unsigned long mask;
unsigned long res;
char *msg;
- int (*action)(struct page *p, unsigned long pfn);
+ int (*action)(struct hwpoison_control *hpc);
} error_states[] = {
{ reserved, reserved, "reserved kernel", me_ignore },
@@ -619,30 +632,29 @@ static struct page_state {
{ 0, 0, "unknown page state", me_unknown },
};
-static void action_result(unsigned long pfn, char *msg, int result)
+static void action_result(struct hwpoison_control *hpc, char *msg, int result)
{
- struct page *page = pfn_to_page(pfn);
-
+ hpc->result = result;
printk(KERN_ERR "MCE %#lx: %s%s page recovery: %s\n",
- pfn,
- PageDirty(page) ? "dirty " : "",
- msg, action_name[result]);
+ hpc->pfn,
+ PageDirty(hpc->page) ? "dirty " : "",
+ msg, hwpoison_result_name[result]);
}
-static int page_action(struct page_state *ps, struct page *p,
- unsigned long pfn)
+static int page_action(struct page_state *ps,
+ struct hwpoison_control *hpc)
{
int result;
int count;
- result = ps->action(p, pfn);
- action_result(pfn, ps->msg, result);
+ result = ps->action(hpc);
+ action_result(hpc, ps->msg, result);
- count = page_count(p) - 1;
+ count = page_count(hpc->page) - 1;
if (count != 0)
printk(KERN_ERR
"MCE %#lx: %s page still referenced by %d users\n",
- pfn, ps->msg, count);
+ hpc->pfn, ps->msg, count);
/* Could do more checks here if page looks ok */
/*
@@ -658,11 +670,12 @@ static int page_action(struct page_state
* Do all that is necessary to remove user space mappings. Unmap
* the pages and send SIGBUS to the processes if the data was dirty.
*/
-static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
- int trapno)
+static int hwpoison_user_mappings(struct hwpoison_control *hpc, int trapno)
{
enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS;
struct address_space *mapping;
+ struct page *p = hpc->page;
+ unsigned long pfn = hpc->pfn;
LIST_HEAD(tokill);
int ret;
int i;
@@ -725,7 +738,8 @@ static int hwpoison_user_mappings(struct
ret = try_to_unmap(p, ttu);
if (ret == SWAP_SUCCESS)
break;
- pr_debug("MCE %#lx: try_to_unmap retry needed %d\n", pfn, ret);
+ pr_debug("MCE %#lx: try_to_unmap retry needed %d\n",
+ pfn, ret);
}
if (ret != SWAP_SUCCESS)
@@ -749,8 +763,10 @@ static int hwpoison_user_mappings(struct
int __memory_failure(unsigned long pfn, int trapno, int ref)
{
+ struct hwpoison_control hpc;
struct page_state *ps;
struct page *p;
+ struct page *page;
int res;
if (!sysctl_memory_failure_recovery)
@@ -763,9 +779,15 @@ int __memory_failure(unsigned long pfn,
return -ENXIO;
}
- p = pfn_to_page(pfn);
+ p = pfn_to_page(pfn);
+ page = compound_head(p);
+
+ hpc.pfn = pfn;
+ hpc.p = p;
+ hpc.page = page;
+
if (TestSetPageHWPoison(p)) {
- action_result(pfn, "already hardware poisoned", IGNORED);
+ action_result(&hpc, "already hardware poisoned", IGNORED);
return 0;
}
@@ -782,12 +804,12 @@ int __memory_failure(unsigned long pfn,
* In fact it's dangerous to directly bump up page count from 0,
* that may make page_freeze_refs()/page_unfreeze_refs() mismatch.
*/
- if (!ref && !get_page_unless_zero(compound_head(p))) {
+ if (!ref && !get_page_unless_zero(page)) {
if (is_free_buddy_page(p)) {
- action_result(pfn, "free buddy", DELAYED);
+ action_result(&hpc, "free buddy", DELAYED);
return 0;
} else {
- action_result(pfn, "high order kernel", IGNORED);
+ action_result(&hpc, "high order kernel", IGNORED);
return -EBUSY;
}
}
@@ -803,7 +825,7 @@ int __memory_failure(unsigned long pfn,
if (!PageLRU(p))
lru_add_drain_all();
if (!PageLRU(p)) {
- action_result(pfn, "non LRU", IGNORED);
+ action_result(&hpc, "non LRU", IGNORED);
put_page(p);
return -EBUSY;
}
@@ -819,7 +841,7 @@ int __memory_failure(unsigned long pfn,
* unpoison always clear PG_hwpoison inside page lock
*/
if (!PageHWPoison(p)) {
- action_result(pfn, "unpoisoned", IGNORED);
+ action_result(&hpc, "unpoisoned", IGNORED);
res = 0;
goto out;
}
@@ -830,7 +852,7 @@ int __memory_failure(unsigned long pfn,
* Now take care of user space mappings.
* Abort on fail: __remove_from_page_cache() assumes unmapped page.
*/
- if (hwpoison_user_mappings(p, pfn, trapno) != SWAP_SUCCESS) {
+ if (hwpoison_user_mappings(&hpc, trapno) != SWAP_SUCCESS) {
res = -EBUSY;
goto out;
}
@@ -839,7 +861,7 @@ int __memory_failure(unsigned long pfn,
* Torn down by someone else?
*/
if (PageLRU(p) && !PageSwapCache(p) && p->mapping == NULL) {
- action_result(pfn, "already truncated LRU", IGNORED);
+ action_result(&hpc, "already truncated LRU", IGNORED);
res = 0;
goto out;
}
@@ -847,7 +869,7 @@ int __memory_failure(unsigned long pfn,
res = -EBUSY;
for (ps = error_states;; ps++) {
if ((p->flags & ps->mask) == ps->res) {
- res = page_action(ps, p, pfn);
+ res = page_action(ps, &hpc);
break;
}
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/