* [PATCH v4 0/6] DFS fixes
@ 2019-12-04 20:37 Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 1/6] cifs: Clean up DFS referral cache Paulo Alcantara (SUSE)
` (6 more replies)
0 siblings, 7 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:37 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE)
Hi,
Follow v4 of DFS fixes and cleanups.
Add kref to vol_info structure and avoid potential races in cache_ttl
(Aurelien).
Paulo Alcantara (SUSE) (6):
cifs: Clean up DFS referral cache
cifs: Get rid of kstrdup_const()'d paths
cifs: Introduce helpers for finding TCP connection
cifs: Merge is_path_valid() into get_normalized_path()
cifs: Fix potential deadlock when updating vol in cifs_reconnect()
cifs: Avoid doing network I/O while holding cache lock
fs/cifs/dfs_cache.c | 1110 +++++++++++++++++++++++--------------------
1 file changed, 586 insertions(+), 524 deletions(-)
--
2.24.0
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v4 1/6] cifs: Clean up DFS referral cache
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
@ 2019-12-04 20:37 ` Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 2/6] cifs: Get rid of kstrdup_const()'d paths Paulo Alcantara (SUSE)
` (5 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:37 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE), Aurelien Aptel
Do some renaming and code cleanup.
No functional changes.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
---
fs/cifs/dfs_cache.c | 565 ++++++++++++++++++++++----------------------
1 file changed, 279 insertions(+), 286 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index 2faa05860a48..aed4183840c5 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -22,60 +22,59 @@
#include "dfs_cache.h"
-#define DFS_CACHE_HTABLE_SIZE 32
-#define DFS_CACHE_MAX_ENTRIES 64
+#define CACHE_HTABLE_SIZE 32
+#define CACHE_MAX_ENTRIES 64
#define IS_INTERLINK_SET(v) ((v) & (DFSREF_REFERRAL_SERVER | \
DFSREF_STORAGE_SERVER))
-struct dfs_cache_tgt {
- char *t_name;
- struct list_head t_list;
+struct cache_dfs_tgt {
+ char *name;
+ struct list_head list;
};
-struct dfs_cache_entry {
- struct hlist_node ce_hlist;
- const char *ce_path;
- int ce_ttl;
- int ce_srvtype;
- int ce_flags;
- struct timespec64 ce_etime;
- int ce_path_consumed;
- int ce_numtgts;
- struct list_head ce_tlist;
- struct dfs_cache_tgt *ce_tgthint;
- struct rcu_head ce_rcu;
+struct cache_entry {
+ struct hlist_node hlist;
+ const char *path;
+ int ttl;
+ int srvtype;
+ int flags;
+ struct timespec64 etime;
+ int path_consumed;
+ int numtgts;
+ struct list_head tlist;
+ struct cache_dfs_tgt *tgthint;
+ struct rcu_head rcu;
};
-static struct kmem_cache *dfs_cache_slab __read_mostly;
-
-struct dfs_cache_vol_info {
- char *vi_fullpath;
- struct smb_vol vi_vol;
- char *vi_mntdata;
- struct list_head vi_list;
+struct vol_info {
+ char *fullpath;
+ struct smb_vol smb_vol;
+ char *mntdata;
+ struct list_head list;
};
-struct dfs_cache {
- struct mutex dc_lock;
- struct nls_table *dc_nlsc;
- struct list_head dc_vol_list;
- int dc_ttl;
- struct delayed_work dc_refresh;
-};
+static struct kmem_cache *cache_slab __read_mostly;
+static struct workqueue_struct *dfscache_wq __read_mostly;
-static struct dfs_cache dfs_cache;
+static int cache_ttl;
+static struct nls_table *cache_nlsc;
/*
* Number of entries in the cache
*/
-static size_t dfs_cache_count;
+static size_t cache_count;
+
+static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
+static DEFINE_MUTEX(list_lock);
-static DEFINE_MUTEX(dfs_cache_list_lock);
-static struct hlist_head dfs_cache_htable[DFS_CACHE_HTABLE_SIZE];
+static LIST_HEAD(vol_list);
+static DEFINE_MUTEX(vol_lock);
static void refresh_cache_worker(struct work_struct *work);
+static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
+
static inline bool is_path_valid(const char *path)
{
return path && (strchr(path + 1, '\\') || strchr(path + 1, '/'));
@@ -100,42 +99,42 @@ static inline void free_normalized_path(const char *path, char *npath)
kfree(npath);
}
-static inline bool cache_entry_expired(const struct dfs_cache_entry *ce)
+static inline bool cache_entry_expired(const struct cache_entry *ce)
{
struct timespec64 ts;
ktime_get_coarse_real_ts64(&ts);
- return timespec64_compare(&ts, &ce->ce_etime) >= 0;
+ return timespec64_compare(&ts, &ce->etime) >= 0;
}
-static inline void free_tgts(struct dfs_cache_entry *ce)
+static inline void free_tgts(struct cache_entry *ce)
{
- struct dfs_cache_tgt *t, *n;
+ struct cache_dfs_tgt *t, *n;
- list_for_each_entry_safe(t, n, &ce->ce_tlist, t_list) {
- list_del(&t->t_list);
- kfree(t->t_name);
+ list_for_each_entry_safe(t, n, &ce->tlist, list) {
+ list_del(&t->list);
+ kfree(t->name);
kfree(t);
}
}
static void free_cache_entry(struct rcu_head *rcu)
{
- struct dfs_cache_entry *ce = container_of(rcu, struct dfs_cache_entry,
- ce_rcu);
- kmem_cache_free(dfs_cache_slab, ce);
+ struct cache_entry *ce = container_of(rcu, struct cache_entry, rcu);
+
+ kmem_cache_free(cache_slab, ce);
}
-static inline void flush_cache_ent(struct dfs_cache_entry *ce)
+static inline void flush_cache_ent(struct cache_entry *ce)
{
- if (hlist_unhashed(&ce->ce_hlist))
+ if (hlist_unhashed(&ce->hlist))
return;
- hlist_del_init_rcu(&ce->ce_hlist);
- kfree_const(ce->ce_path);
+ hlist_del_init_rcu(&ce->hlist);
+ kfree_const(ce->path);
free_tgts(ce);
- dfs_cache_count--;
- call_rcu(&ce->ce_rcu, free_cache_entry);
+ cache_count--;
+ call_rcu(&ce->rcu, free_cache_entry);
}
static void flush_cache_ents(void)
@@ -143,11 +142,11 @@ static void flush_cache_ents(void)
int i;
rcu_read_lock();
- for (i = 0; i < DFS_CACHE_HTABLE_SIZE; i++) {
- struct hlist_head *l = &dfs_cache_htable[i];
- struct dfs_cache_entry *ce;
+ for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+ struct hlist_head *l = &cache_htable[i];
+ struct cache_entry *ce;
- hlist_for_each_entry_rcu(ce, l, ce_hlist)
+ hlist_for_each_entry_rcu(ce, l, hlist)
flush_cache_ent(ce);
}
rcu_read_unlock();
@@ -159,35 +158,35 @@ static void flush_cache_ents(void)
static int dfscache_proc_show(struct seq_file *m, void *v)
{
int bucket;
- struct dfs_cache_entry *ce;
- struct dfs_cache_tgt *t;
+ struct cache_entry *ce;
+ struct cache_dfs_tgt *t;
seq_puts(m, "DFS cache\n---------\n");
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
rcu_read_lock();
- hash_for_each_rcu(dfs_cache_htable, bucket, ce, ce_hlist) {
+ hash_for_each_rcu(cache_htable, bucket, ce, hlist) {
seq_printf(m,
"cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
"interlink=%s,path_consumed=%d,expired=%s\n",
- ce->ce_path,
- ce->ce_srvtype == DFS_TYPE_ROOT ? "root" : "link",
- ce->ce_ttl, ce->ce_etime.tv_nsec,
- IS_INTERLINK_SET(ce->ce_flags) ? "yes" : "no",
- ce->ce_path_consumed,
+ ce->path,
+ ce->srvtype == DFS_TYPE_ROOT ? "root" : "link",
+ ce->ttl, ce->etime.tv_nsec,
+ IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
+ ce->path_consumed,
cache_entry_expired(ce) ? "yes" : "no");
- list_for_each_entry(t, &ce->ce_tlist, t_list) {
+ list_for_each_entry(t, &ce->tlist, list) {
seq_printf(m, " %s%s\n",
- t->t_name,
- ce->ce_tgthint == t ? " (target hint)" : "");
+ t->name,
+ ce->tgthint == t ? " (target hint)" : "");
}
}
rcu_read_unlock();
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
return 0;
}
@@ -205,9 +204,9 @@ static ssize_t dfscache_proc_write(struct file *file, const char __user *buffer,
return -EINVAL;
cifs_dbg(FYI, "clearing dfs cache");
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
flush_cache_ents();
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
return count;
}
@@ -226,25 +225,25 @@ const struct file_operations dfscache_proc_fops = {
};
#ifdef CONFIG_CIFS_DEBUG2
-static inline void dump_tgts(const struct dfs_cache_entry *ce)
+static inline void dump_tgts(const struct cache_entry *ce)
{
- struct dfs_cache_tgt *t;
+ struct cache_dfs_tgt *t;
cifs_dbg(FYI, "target list:\n");
- list_for_each_entry(t, &ce->ce_tlist, t_list) {
- cifs_dbg(FYI, " %s%s\n", t->t_name,
- ce->ce_tgthint == t ? " (target hint)" : "");
+ list_for_each_entry(t, &ce->tlist, list) {
+ cifs_dbg(FYI, " %s%s\n", t->name,
+ ce->tgthint == t ? " (target hint)" : "");
}
}
-static inline void dump_ce(const struct dfs_cache_entry *ce)
+static inline void dump_ce(const struct cache_entry *ce)
{
cifs_dbg(FYI, "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
- "interlink=%s,path_consumed=%d,expired=%s\n", ce->ce_path,
- ce->ce_srvtype == DFS_TYPE_ROOT ? "root" : "link", ce->ce_ttl,
- ce->ce_etime.tv_nsec,
- IS_INTERLINK_SET(ce->ce_flags) ? "yes" : "no",
- ce->ce_path_consumed,
+ "interlink=%s,path_consumed=%d,expired=%s\n", ce->path,
+ ce->srvtype == DFS_TYPE_ROOT ? "root" : "link", ce->ttl,
+ ce->etime.tv_nsec,
+ IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
+ ce->path_consumed,
cache_entry_expired(ce) ? "yes" : "no");
dump_tgts(ce);
}
@@ -284,25 +283,34 @@ static inline void dump_refs(const struct dfs_info3_param *refs, int numrefs)
*/
int dfs_cache_init(void)
{
+ int rc;
int i;
- dfs_cache_slab = kmem_cache_create("cifs_dfs_cache",
- sizeof(struct dfs_cache_entry), 0,
- SLAB_HWCACHE_ALIGN, NULL);
- if (!dfs_cache_slab)
+ dfscache_wq = alloc_workqueue("cifs-dfscache",
+ WQ_FREEZABLE | WQ_MEM_RECLAIM, 1);
+ if (!dfscache_wq)
return -ENOMEM;
- for (i = 0; i < DFS_CACHE_HTABLE_SIZE; i++)
- INIT_HLIST_HEAD(&dfs_cache_htable[i]);
+ cache_slab = kmem_cache_create("cifs_dfs_cache",
+ sizeof(struct cache_entry), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!cache_slab) {
+ rc = -ENOMEM;
+ goto out_destroy_wq;
+ }
+
+ for (i = 0; i < CACHE_HTABLE_SIZE; i++)
+ INIT_HLIST_HEAD(&cache_htable[i]);
- INIT_LIST_HEAD(&dfs_cache.dc_vol_list);
- mutex_init(&dfs_cache.dc_lock);
- INIT_DELAYED_WORK(&dfs_cache.dc_refresh, refresh_cache_worker);
- dfs_cache.dc_ttl = -1;
- dfs_cache.dc_nlsc = load_nls_default();
+ cache_ttl = -1;
+ cache_nlsc = load_nls_default();
cifs_dbg(FYI, "%s: initialized DFS referral cache\n", __func__);
return 0;
+
+out_destroy_wq:
+ destroy_workqueue(dfscache_wq);
+ return rc;
}
static inline unsigned int cache_entry_hash(const void *data, int size)
@@ -310,7 +318,7 @@ static inline unsigned int cache_entry_hash(const void *data, int size)
unsigned int h;
h = jhash(data, size, 0);
- return h & (DFS_CACHE_HTABLE_SIZE - 1);
+ return h & (CACHE_HTABLE_SIZE - 1);
}
/* Check whether second path component of @path is SYSVOL or NETLOGON */
@@ -325,11 +333,11 @@ static inline bool is_sysvol_or_netlogon(const char *path)
}
/* Return target hint of a DFS cache entry */
-static inline char *get_tgt_name(const struct dfs_cache_entry *ce)
+static inline char *get_tgt_name(const struct cache_entry *ce)
{
- struct dfs_cache_tgt *t = ce->ce_tgthint;
+ struct cache_dfs_tgt *t = ce->tgthint;
- return t ? t->t_name : ERR_PTR(-ENOENT);
+ return t ? t->name : ERR_PTR(-ENOENT);
}
/* Return expire time out of a new entry's TTL */
@@ -346,19 +354,19 @@ static inline struct timespec64 get_expire_time(int ttl)
}
/* Allocate a new DFS target */
-static inline struct dfs_cache_tgt *alloc_tgt(const char *name)
+static inline struct cache_dfs_tgt *alloc_tgt(const char *name)
{
- struct dfs_cache_tgt *t;
+ struct cache_dfs_tgt *t;
t = kmalloc(sizeof(*t), GFP_KERNEL);
if (!t)
return ERR_PTR(-ENOMEM);
- t->t_name = kstrndup(name, strlen(name), GFP_KERNEL);
- if (!t->t_name) {
+ t->name = kstrndup(name, strlen(name), GFP_KERNEL);
+ if (!t->name) {
kfree(t);
return ERR_PTR(-ENOMEM);
}
- INIT_LIST_HEAD(&t->t_list);
+ INIT_LIST_HEAD(&t->list);
return t;
}
@@ -367,63 +375,63 @@ static inline struct dfs_cache_tgt *alloc_tgt(const char *name)
* target hint.
*/
static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs,
- struct dfs_cache_entry *ce, const char *tgthint)
+ struct cache_entry *ce, const char *tgthint)
{
int i;
- ce->ce_ttl = refs[0].ttl;
- ce->ce_etime = get_expire_time(ce->ce_ttl);
- ce->ce_srvtype = refs[0].server_type;
- ce->ce_flags = refs[0].ref_flag;
- ce->ce_path_consumed = refs[0].path_consumed;
+ ce->ttl = refs[0].ttl;
+ ce->etime = get_expire_time(ce->ttl);
+ ce->srvtype = refs[0].server_type;
+ ce->flags = refs[0].ref_flag;
+ ce->path_consumed = refs[0].path_consumed;
for (i = 0; i < numrefs; i++) {
- struct dfs_cache_tgt *t;
+ struct cache_dfs_tgt *t;
t = alloc_tgt(refs[i].node_name);
if (IS_ERR(t)) {
free_tgts(ce);
return PTR_ERR(t);
}
- if (tgthint && !strcasecmp(t->t_name, tgthint)) {
- list_add(&t->t_list, &ce->ce_tlist);
+ if (tgthint && !strcasecmp(t->name, tgthint)) {
+ list_add(&t->list, &ce->tlist);
tgthint = NULL;
} else {
- list_add_tail(&t->t_list, &ce->ce_tlist);
+ list_add_tail(&t->list, &ce->tlist);
}
- ce->ce_numtgts++;
+ ce->numtgts++;
}
- ce->ce_tgthint = list_first_entry_or_null(&ce->ce_tlist,
- struct dfs_cache_tgt, t_list);
+ ce->tgthint = list_first_entry_or_null(&ce->tlist,
+ struct cache_dfs_tgt, list);
return 0;
}
/* Allocate a new cache entry */
-static struct dfs_cache_entry *
-alloc_cache_entry(const char *path, const struct dfs_info3_param *refs,
- int numrefs)
+static struct cache_entry *alloc_cache_entry(const char *path,
+ const struct dfs_info3_param *refs,
+ int numrefs)
{
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
int rc;
- ce = kmem_cache_zalloc(dfs_cache_slab, GFP_KERNEL);
+ ce = kmem_cache_zalloc(cache_slab, GFP_KERNEL);
if (!ce)
return ERR_PTR(-ENOMEM);
- ce->ce_path = kstrdup_const(path, GFP_KERNEL);
- if (!ce->ce_path) {
- kmem_cache_free(dfs_cache_slab, ce);
+ ce->path = kstrdup_const(path, GFP_KERNEL);
+ if (!ce->path) {
+ kmem_cache_free(cache_slab, ce);
return ERR_PTR(-ENOMEM);
}
- INIT_HLIST_NODE(&ce->ce_hlist);
- INIT_LIST_HEAD(&ce->ce_tlist);
+ INIT_HLIST_NODE(&ce->hlist);
+ INIT_LIST_HEAD(&ce->tlist);
rc = copy_ref_data(refs, numrefs, ce, NULL);
if (rc) {
- kfree_const(ce->ce_path);
- kmem_cache_free(dfs_cache_slab, ce);
+ kfree_const(ce->path);
+ kmem_cache_free(cache_slab, ce);
ce = ERR_PTR(rc);
}
return ce;
@@ -432,13 +440,13 @@ alloc_cache_entry(const char *path, const struct dfs_info3_param *refs,
static void remove_oldest_entry(void)
{
int bucket;
- struct dfs_cache_entry *ce;
- struct dfs_cache_entry *to_del = NULL;
+ struct cache_entry *ce;
+ struct cache_entry *to_del = NULL;
rcu_read_lock();
- hash_for_each_rcu(dfs_cache_htable, bucket, ce, ce_hlist) {
- if (!to_del || timespec64_compare(&ce->ce_etime,
- &to_del->ce_etime) < 0)
+ hash_for_each_rcu(cache_htable, bucket, ce, hlist) {
+ if (!to_del || timespec64_compare(&ce->etime,
+ &to_del->etime) < 0)
to_del = ce;
}
if (!to_del) {
@@ -453,93 +461,84 @@ static void remove_oldest_entry(void)
}
/* Add a new DFS cache entry */
-static inline struct dfs_cache_entry *
+static inline struct cache_entry *
add_cache_entry(unsigned int hash, const char *path,
const struct dfs_info3_param *refs, int numrefs)
{
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
ce = alloc_cache_entry(path, refs, numrefs);
if (IS_ERR(ce))
return ce;
- hlist_add_head_rcu(&ce->ce_hlist, &dfs_cache_htable[hash]);
+ hlist_add_head_rcu(&ce->hlist, &cache_htable[hash]);
- mutex_lock(&dfs_cache.dc_lock);
- if (dfs_cache.dc_ttl < 0) {
- dfs_cache.dc_ttl = ce->ce_ttl;
- queue_delayed_work(cifsiod_wq, &dfs_cache.dc_refresh,
- dfs_cache.dc_ttl * HZ);
+ mutex_lock(&vol_lock);
+ if (cache_ttl < 0) {
+ cache_ttl = ce->ttl;
+ queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
} else {
- dfs_cache.dc_ttl = min_t(int, dfs_cache.dc_ttl, ce->ce_ttl);
- mod_delayed_work(cifsiod_wq, &dfs_cache.dc_refresh,
- dfs_cache.dc_ttl * HZ);
+ cache_ttl = min_t(int, cache_ttl, ce->ttl);
+ mod_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
}
- mutex_unlock(&dfs_cache.dc_lock);
+ mutex_unlock(&vol_lock);
return ce;
}
-static struct dfs_cache_entry *__find_cache_entry(unsigned int hash,
- const char *path)
+/*
+ * Find a DFS cache entry in hash table and optionally check prefix path against
+ * @path.
+ * Use whole path components in the match.
+ * Return ERR_PTR(-ENOENT) if the entry is not found.
+ */
+static struct cache_entry *lookup_cache_entry(const char *path,
+ unsigned int *hash)
{
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
+ unsigned int h;
bool found = false;
- rcu_read_lock();
- hlist_for_each_entry_rcu(ce, &dfs_cache_htable[hash], ce_hlist) {
- if (!strcasecmp(path, ce->ce_path)) {
-#ifdef CONFIG_CIFS_DEBUG2
- char *name = get_tgt_name(ce);
+ h = cache_entry_hash(path, strlen(path));
- if (IS_ERR(name)) {
- rcu_read_unlock();
- return ERR_CAST(name);
- }
- cifs_dbg(FYI, "%s: cache hit\n", __func__);
- cifs_dbg(FYI, "%s: target hint: %s\n", __func__, name);
-#endif
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(ce, &cache_htable[h], hlist) {
+ if (!strcasecmp(path, ce->path)) {
found = true;
+ dump_ce(ce);
break;
}
}
rcu_read_unlock();
- return found ? ce : ERR_PTR(-ENOENT);
-}
-/*
- * Find a DFS cache entry in hash table and optionally check prefix path against
- * @path.
- * Use whole path components in the match.
- * Return ERR_PTR(-ENOENT) if the entry is not found.
- */
-static inline struct dfs_cache_entry *find_cache_entry(const char *path,
- unsigned int *hash)
-{
- *hash = cache_entry_hash(path, strlen(path));
- return __find_cache_entry(*hash, path);
+ if (!found)
+ ce = ERR_PTR(-ENOENT);
+ if (hash)
+ *hash = h;
+
+ return ce;
}
static inline void destroy_slab_cache(void)
{
rcu_barrier();
- kmem_cache_destroy(dfs_cache_slab);
+ kmem_cache_destroy(cache_slab);
}
-static inline void free_vol(struct dfs_cache_vol_info *vi)
+static inline void free_vol(struct vol_info *vi)
{
- list_del(&vi->vi_list);
- kfree(vi->vi_fullpath);
- kfree(vi->vi_mntdata);
- cifs_cleanup_volume_info_contents(&vi->vi_vol);
+ list_del(&vi->list);
+ kfree(vi->fullpath);
+ kfree(vi->mntdata);
+ cifs_cleanup_volume_info_contents(&vi->smb_vol);
kfree(vi);
}
static inline void free_vol_list(void)
{
- struct dfs_cache_vol_info *vi, *nvi;
+ struct vol_info *vi, *nvi;
- list_for_each_entry_safe(vi, nvi, &dfs_cache.dc_vol_list, vi_list)
+ list_for_each_entry_safe(vi, nvi, &vol_list, list)
free_vol(vi);
}
@@ -548,40 +547,38 @@ static inline void free_vol_list(void)
*/
void dfs_cache_destroy(void)
{
- cancel_delayed_work_sync(&dfs_cache.dc_refresh);
- unload_nls(dfs_cache.dc_nlsc);
+ cancel_delayed_work_sync(&refresh_task);
+ unload_nls(cache_nlsc);
free_vol_list();
- mutex_destroy(&dfs_cache.dc_lock);
-
flush_cache_ents();
destroy_slab_cache();
- mutex_destroy(&dfs_cache_list_lock);
+ destroy_workqueue(dfscache_wq);
cifs_dbg(FYI, "%s: destroyed DFS referral cache\n", __func__);
}
-static inline struct dfs_cache_entry *
+static inline struct cache_entry *
__update_cache_entry(const char *path, const struct dfs_info3_param *refs,
int numrefs)
{
int rc;
unsigned int h;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
char *s, *th = NULL;
- ce = find_cache_entry(path, &h);
+ ce = lookup_cache_entry(path, &h);
if (IS_ERR(ce))
return ce;
- if (ce->ce_tgthint) {
- s = ce->ce_tgthint->t_name;
+ if (ce->tgthint) {
+ s = ce->tgthint->name;
th = kstrndup(s, strlen(s), GFP_KERNEL);
if (!th)
return ERR_PTR(-ENOMEM);
}
free_tgts(ce);
- ce->ce_numtgts = 0;
+ ce->numtgts = 0;
rc = copy_ref_data(refs, numrefs, ce, th);
kfree(th);
@@ -593,10 +590,10 @@ __update_cache_entry(const char *path, const struct dfs_info3_param *refs,
}
/* Update an expired cache entry by getting a new DFS referral from server */
-static struct dfs_cache_entry *
+static struct cache_entry *
update_cache_entry(const unsigned int xid, struct cifs_ses *ses,
const struct nls_table *nls_codepage, int remap,
- const char *path, struct dfs_cache_entry *ce)
+ const char *path, struct cache_entry *ce)
{
int rc;
struct dfs_info3_param *refs = NULL;
@@ -636,20 +633,20 @@ update_cache_entry(const unsigned int xid, struct cifs_ses *ses,
* For interlinks, __cifs_dfs_mount() and expand_dfs_referral() are supposed to
* handle them properly.
*/
-static struct dfs_cache_entry *
+static struct cache_entry *
do_dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
const struct nls_table *nls_codepage, int remap,
const char *path, bool noreq)
{
int rc;
unsigned int h;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
struct dfs_info3_param *nrefs;
int numnrefs;
cifs_dbg(FYI, "%s: search path: %s\n", __func__, path);
- ce = find_cache_entry(path, &h);
+ ce = lookup_cache_entry(path, &h);
if (IS_ERR(ce)) {
cifs_dbg(FYI, "%s: cache miss\n", __func__);
/*
@@ -690,9 +687,9 @@ do_dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
cifs_dbg(FYI, "%s: new cache entry\n", __func__);
- if (dfs_cache_count >= DFS_CACHE_MAX_ENTRIES) {
+ if (cache_count >= CACHE_MAX_ENTRIES) {
cifs_dbg(FYI, "%s: reached max cache size (%d)",
- __func__, DFS_CACHE_MAX_ENTRIES);
+ __func__, CACHE_MAX_ENTRIES);
remove_oldest_entry();
}
ce = add_cache_entry(h, path, nrefs, numnrefs);
@@ -701,7 +698,7 @@ do_dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
if (IS_ERR(ce))
return ce;
- dfs_cache_count++;
+ cache_count++;
}
dump_ce(ce);
@@ -723,7 +720,7 @@ do_dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
}
/* Set up a new DFS referral from a given cache entry */
-static int setup_ref(const char *path, const struct dfs_cache_entry *ce,
+static int setup_ref(const char *path, const struct cache_entry *ce,
struct dfs_info3_param *ref, const char *tgt)
{
int rc;
@@ -736,7 +733,7 @@ static int setup_ref(const char *path, const struct dfs_cache_entry *ce,
if (!ref->path_name)
return -ENOMEM;
- ref->path_consumed = ce->ce_path_consumed;
+ ref->path_consumed = ce->path_consumed;
ref->node_name = kstrndup(tgt, strlen(tgt), GFP_KERNEL);
if (!ref->node_name) {
@@ -744,9 +741,9 @@ static int setup_ref(const char *path, const struct dfs_cache_entry *ce,
goto err_free_path;
}
- ref->ttl = ce->ce_ttl;
- ref->server_type = ce->ce_srvtype;
- ref->ref_flag = ce->ce_flags;
+ ref->ttl = ce->ttl;
+ ref->server_type = ce->srvtype;
+ ref->ref_flag = ce->flags;
return 0;
@@ -757,25 +754,25 @@ static int setup_ref(const char *path, const struct dfs_cache_entry *ce,
}
/* Return target list of a DFS cache entry */
-static int get_tgt_list(const struct dfs_cache_entry *ce,
+static int get_tgt_list(const struct cache_entry *ce,
struct dfs_cache_tgt_list *tl)
{
int rc;
struct list_head *head = &tl->tl_list;
- struct dfs_cache_tgt *t;
+ struct cache_dfs_tgt *t;
struct dfs_cache_tgt_iterator *it, *nit;
memset(tl, 0, sizeof(*tl));
INIT_LIST_HEAD(head);
- list_for_each_entry(t, &ce->ce_tlist, t_list) {
+ list_for_each_entry(t, &ce->tlist, list) {
it = kzalloc(sizeof(*it), GFP_KERNEL);
if (!it) {
rc = -ENOMEM;
goto err_free_it;
}
- it->it_name = kstrndup(t->t_name, strlen(t->t_name),
+ it->it_name = kstrndup(t->name, strlen(t->name),
GFP_KERNEL);
if (!it->it_name) {
kfree(it);
@@ -783,12 +780,12 @@ static int get_tgt_list(const struct dfs_cache_entry *ce,
goto err_free_it;
}
- if (ce->ce_tgthint == t)
+ if (ce->tgthint == t)
list_add(&it->it_list, head);
else
list_add_tail(&it->it_list, head);
}
- tl->tl_numtgts = ce->ce_numtgts;
+ tl->tl_numtgts = ce->numtgts;
return 0;
@@ -829,7 +826,7 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
{
int rc;
char *npath;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
if (unlikely(!is_path_valid(path)))
return -EINVAL;
@@ -838,7 +835,7 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
if (rc)
return rc;
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
ce = do_dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
if (!IS_ERR(ce)) {
if (ref)
@@ -850,7 +847,7 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
} else {
rc = PTR_ERR(ce);
}
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
free_normalized_path(path, npath);
return rc;
}
@@ -876,7 +873,7 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
{
int rc;
char *npath;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
if (unlikely(!is_path_valid(path)))
return -EINVAL;
@@ -885,7 +882,7 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
if (rc)
return rc;
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
ce = do_dfs_cache_find(0, NULL, NULL, 0, npath, true);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
@@ -899,7 +896,7 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
if (!rc && tgt_list)
rc = get_tgt_list(ce, tgt_list);
out:
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
free_normalized_path(path, npath);
return rc;
}
@@ -929,8 +926,8 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
{
int rc;
char *npath;
- struct dfs_cache_entry *ce;
- struct dfs_cache_tgt *t;
+ struct cache_entry *ce;
+ struct cache_dfs_tgt *t;
if (unlikely(!is_path_valid(path)))
return -EINVAL;
@@ -941,7 +938,7 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
ce = do_dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
@@ -950,14 +947,14 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
rc = 0;
- t = ce->ce_tgthint;
+ t = ce->tgthint;
- if (likely(!strcasecmp(it->it_name, t->t_name)))
+ if (likely(!strcasecmp(it->it_name, t->name)))
goto out;
- list_for_each_entry(t, &ce->ce_tlist, t_list) {
- if (!strcasecmp(t->t_name, it->it_name)) {
- ce->ce_tgthint = t;
+ list_for_each_entry(t, &ce->tlist, list) {
+ if (!strcasecmp(t->name, it->it_name)) {
+ ce->tgthint = t;
cifs_dbg(FYI, "%s: new target hint: %s\n", __func__,
it->it_name);
break;
@@ -965,7 +962,7 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
}
out:
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
free_normalized_path(path, npath);
return rc;
}
@@ -989,8 +986,8 @@ int dfs_cache_noreq_update_tgthint(const char *path,
{
int rc;
char *npath;
- struct dfs_cache_entry *ce;
- struct dfs_cache_tgt *t;
+ struct cache_entry *ce;
+ struct cache_dfs_tgt *t;
if (unlikely(!is_path_valid(path)) || !it)
return -EINVAL;
@@ -1001,7 +998,7 @@ int dfs_cache_noreq_update_tgthint(const char *path,
cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
ce = do_dfs_cache_find(0, NULL, NULL, 0, npath, true);
if (IS_ERR(ce)) {
@@ -1011,14 +1008,14 @@ int dfs_cache_noreq_update_tgthint(const char *path,
rc = 0;
- t = ce->ce_tgthint;
+ t = ce->tgthint;
- if (unlikely(!strcasecmp(it->it_name, t->t_name)))
+ if (unlikely(!strcasecmp(it->it_name, t->name)))
goto out;
- list_for_each_entry(t, &ce->ce_tlist, t_list) {
- if (!strcasecmp(t->t_name, it->it_name)) {
- ce->ce_tgthint = t;
+ list_for_each_entry(t, &ce->tlist, list) {
+ if (!strcasecmp(t->name, it->it_name)) {
+ ce->tgthint = t;
cifs_dbg(FYI, "%s: new target hint: %s\n", __func__,
it->it_name);
break;
@@ -1026,7 +1023,7 @@ int dfs_cache_noreq_update_tgthint(const char *path,
}
out:
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
free_normalized_path(path, npath);
return rc;
}
@@ -1047,7 +1044,7 @@ int dfs_cache_get_tgt_referral(const char *path,
{
int rc;
char *npath;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
unsigned int h;
if (!it || !ref)
@@ -1061,9 +1058,9 @@ int dfs_cache_get_tgt_referral(const char *path,
cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
- ce = find_cache_entry(npath, &h);
+ ce = lookup_cache_entry(npath, &h);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
goto out;
@@ -1074,7 +1071,7 @@ int dfs_cache_get_tgt_referral(const char *path,
rc = setup_ref(path, ce, ref, it->it_name);
out:
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
free_normalized_path(path, npath);
return rc;
}
@@ -1085,7 +1082,7 @@ static int dup_vol(struct smb_vol *vol, struct smb_vol *new)
if (vol->username) {
new->username = kstrndup(vol->username, strlen(vol->username),
- GFP_KERNEL);
+ GFP_KERNEL);
if (!new->username)
return -ENOMEM;
}
@@ -1103,7 +1100,7 @@ static int dup_vol(struct smb_vol *vol, struct smb_vol *new)
}
if (vol->domainname) {
new->domainname = kstrndup(vol->domainname,
- strlen(vol->domainname), GFP_KERNEL);
+ strlen(vol->domainname), GFP_KERNEL);
if (!new->domainname)
goto err_free_unc;
}
@@ -1150,7 +1147,7 @@ static int dup_vol(struct smb_vol *vol, struct smb_vol *new)
int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol, const char *fullpath)
{
int rc;
- struct dfs_cache_vol_info *vi;
+ struct vol_info *vi;
if (!vol || !fullpath || !mntdata)
return -EINVAL;
@@ -1161,38 +1158,37 @@ int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol, const char *fullpath)
if (!vi)
return -ENOMEM;
- vi->vi_fullpath = kstrndup(fullpath, strlen(fullpath), GFP_KERNEL);
- if (!vi->vi_fullpath) {
+ vi->fullpath = kstrndup(fullpath, strlen(fullpath), GFP_KERNEL);
+ if (!vi->fullpath) {
rc = -ENOMEM;
goto err_free_vi;
}
- rc = dup_vol(vol, &vi->vi_vol);
+ rc = dup_vol(vol, &vi->smb_vol);
if (rc)
goto err_free_fullpath;
- vi->vi_mntdata = mntdata;
+ vi->mntdata = mntdata;
- mutex_lock(&dfs_cache.dc_lock);
- list_add_tail(&vi->vi_list, &dfs_cache.dc_vol_list);
- mutex_unlock(&dfs_cache.dc_lock);
+ mutex_lock(&vol_lock);
+ list_add_tail(&vi->list, &vol_list);
+ mutex_unlock(&vol_lock);
return 0;
err_free_fullpath:
- kfree(vi->vi_fullpath);
+ kfree(vi->fullpath);
err_free_vi:
kfree(vi);
return rc;
}
-static inline struct dfs_cache_vol_info *find_vol(const char *fullpath)
+static inline struct vol_info *find_vol(const char *fullpath)
{
- struct dfs_cache_vol_info *vi;
+ struct vol_info *vi;
- list_for_each_entry(vi, &dfs_cache.dc_vol_list, vi_list) {
- cifs_dbg(FYI, "%s: vi->vi_fullpath: %s\n", __func__,
- vi->vi_fullpath);
- if (!strcasecmp(vi->vi_fullpath, fullpath))
+ list_for_each_entry(vi, &vol_list, list) {
+ cifs_dbg(FYI, "%s: vi->fullpath: %s\n", __func__, vi->fullpath);
+ if (!strcasecmp(vi->fullpath, fullpath))
return vi;
}
return ERR_PTR(-ENOENT);
@@ -1209,14 +1205,14 @@ static inline struct dfs_cache_vol_info *find_vol(const char *fullpath)
int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
{
int rc;
- struct dfs_cache_vol_info *vi;
+ struct vol_info *vi;
if (!fullpath || !server)
return -EINVAL;
cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
- mutex_lock(&dfs_cache.dc_lock);
+ mutex_lock(&vol_lock);
vi = find_vol(fullpath);
if (IS_ERR(vi)) {
@@ -1225,12 +1221,12 @@ int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
}
cifs_dbg(FYI, "%s: updating volume info\n", __func__);
- memcpy(&vi->vi_vol.dstaddr, &server->dstaddr,
- sizeof(vi->vi_vol.dstaddr));
+ memcpy(&vi->smb_vol.dstaddr, &server->dstaddr,
+ sizeof(vi->smb_vol.dstaddr));
rc = 0;
out:
- mutex_unlock(&dfs_cache.dc_lock);
+ mutex_unlock(&vol_lock);
return rc;
}
@@ -1241,18 +1237,18 @@ int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
*/
void dfs_cache_del_vol(const char *fullpath)
{
- struct dfs_cache_vol_info *vi;
+ struct vol_info *vi;
if (!fullpath || !*fullpath)
return;
cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
- mutex_lock(&dfs_cache.dc_lock);
+ mutex_lock(&vol_lock);
vi = find_vol(fullpath);
if (!IS_ERR(vi))
free_vol(vi);
- mutex_unlock(&dfs_cache.dc_lock);
+ mutex_unlock(&vol_lock);
}
/* Get all tcons that are within a DFS namespace and can be refreshed */
@@ -1280,7 +1276,7 @@ static void get_tcons(struct TCP_Server_Info *server, struct list_head *head)
spin_unlock(&cifs_tcp_ses_lock);
}
-static inline bool is_dfs_link(const char *path)
+static bool is_dfs_link(const char *path)
{
char *s;
@@ -1290,7 +1286,7 @@ static inline bool is_dfs_link(const char *path)
return !!strchr(s + 1, '\\');
}
-static inline char *get_dfs_root(const char *path)
+static char *get_dfs_root(const char *path)
{
char *s, *npath;
@@ -1310,8 +1306,9 @@ static inline char *get_dfs_root(const char *path)
}
/* Find root SMB session out of a DFS link path */
-static struct cifs_ses *find_root_ses(struct dfs_cache_vol_info *vi,
- struct cifs_tcon *tcon, const char *path)
+static struct cifs_ses *find_root_ses(struct vol_info *vi,
+ struct cifs_tcon *tcon,
+ const char *path)
{
char *rpath;
int rc;
@@ -1333,8 +1330,7 @@ static struct cifs_ses *find_root_ses(struct dfs_cache_vol_info *vi,
goto out;
}
- mdata = cifs_compose_mount_options(vi->vi_mntdata, rpath, &ref,
- &devname);
+ mdata = cifs_compose_mount_options(vi->mntdata, rpath, &ref, &devname);
free_dfs_info_param(&ref);
if (IS_ERR(mdata)) {
@@ -1373,14 +1369,13 @@ static struct cifs_ses *find_root_ses(struct dfs_cache_vol_info *vi,
}
/* Refresh DFS cache entry from a given tcon */
-static void do_refresh_tcon(struct dfs_cache *dc, struct dfs_cache_vol_info *vi,
- struct cifs_tcon *tcon)
+static void refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
{
int rc = 0;
unsigned int xid;
char *path, *npath;
unsigned int h;
- struct dfs_cache_entry *ce;
+ struct cache_entry *ce;
struct dfs_info3_param *refs = NULL;
int numrefs = 0;
struct cifs_ses *root_ses = NULL, *ses;
@@ -1393,9 +1388,9 @@ static void do_refresh_tcon(struct dfs_cache *dc, struct dfs_cache_vol_info *vi,
if (rc)
goto out;
- mutex_lock(&dfs_cache_list_lock);
- ce = find_cache_entry(npath, &h);
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
+ ce = lookup_cache_entry(npath, &h);
+ mutex_unlock(&list_lock);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
@@ -1421,12 +1416,12 @@ static void do_refresh_tcon(struct dfs_cache *dc, struct dfs_cache_vol_info *vi,
rc = -EOPNOTSUPP;
} else {
rc = ses->server->ops->get_dfs_refer(xid, ses, path, &refs,
- &numrefs, dc->dc_nlsc,
+ &numrefs, cache_nlsc,
tcon->remap);
if (!rc) {
- mutex_lock(&dfs_cache_list_lock);
+ mutex_lock(&list_lock);
ce = __update_cache_entry(npath, refs, numrefs);
- mutex_unlock(&dfs_cache_list_lock);
+ mutex_unlock(&list_lock);
dump_refs(refs, numrefs);
free_dfs_info_array(refs, numrefs);
if (IS_ERR(ce))
@@ -1448,30 +1443,28 @@ static void do_refresh_tcon(struct dfs_cache *dc, struct dfs_cache_vol_info *vi,
*/
static void refresh_cache_worker(struct work_struct *work)
{
- struct dfs_cache *dc = container_of(work, struct dfs_cache,
- dc_refresh.work);
- struct dfs_cache_vol_info *vi;
+ struct vol_info *vi;
struct TCP_Server_Info *server;
LIST_HEAD(list);
struct cifs_tcon *tcon, *ntcon;
- mutex_lock(&dc->dc_lock);
+ mutex_lock(&vol_lock);
- list_for_each_entry(vi, &dc->dc_vol_list, vi_list) {
- server = cifs_find_tcp_session(&vi->vi_vol);
+ list_for_each_entry(vi, &vol_list, list) {
+ server = cifs_find_tcp_session(&vi->smb_vol);
if (IS_ERR_OR_NULL(server))
continue;
if (server->tcpStatus != CifsGood)
goto next;
get_tcons(server, &list);
list_for_each_entry_safe(tcon, ntcon, &list, ulist) {
- do_refresh_tcon(dc, vi, tcon);
+ refresh_tcon(vi, tcon);
list_del_init(&tcon->ulist);
cifs_put_tcon(tcon);
}
next:
cifs_put_tcp_session(server, 0);
}
- queue_delayed_work(cifsiod_wq, &dc->dc_refresh, dc->dc_ttl * HZ);
- mutex_unlock(&dc->dc_lock);
+ queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
+ mutex_unlock(&vol_lock);
}
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 2/6] cifs: Get rid of kstrdup_const()'d paths
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 1/6] cifs: Clean up DFS referral cache Paulo Alcantara (SUSE)
@ 2019-12-04 20:37 ` Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 3/6] cifs: Introduce helpers for finding TCP connection Paulo Alcantara (SUSE)
` (4 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:37 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE), Aurelien Aptel
The DFS cache API is mostly used with heap allocated strings.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
---
fs/cifs/dfs_cache.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index aed4183840c5..49c5f045270f 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -131,7 +131,7 @@ static inline void flush_cache_ent(struct cache_entry *ce)
return;
hlist_del_init_rcu(&ce->hlist);
- kfree_const(ce->path);
+ kfree(ce->path);
free_tgts(ce);
cache_count--;
call_rcu(&ce->rcu, free_cache_entry);
@@ -420,7 +420,7 @@ static struct cache_entry *alloc_cache_entry(const char *path,
if (!ce)
return ERR_PTR(-ENOMEM);
- ce->path = kstrdup_const(path, GFP_KERNEL);
+ ce->path = kstrndup(path, strlen(path), GFP_KERNEL);
if (!ce->path) {
kmem_cache_free(cache_slab, ce);
return ERR_PTR(-ENOMEM);
@@ -430,7 +430,7 @@ static struct cache_entry *alloc_cache_entry(const char *path,
rc = copy_ref_data(refs, numrefs, ce, NULL);
if (rc) {
- kfree_const(ce->path);
+ kfree(ce->path);
kmem_cache_free(cache_slab, ce);
ce = ERR_PTR(rc);
}
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 3/6] cifs: Introduce helpers for finding TCP connection
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 1/6] cifs: Clean up DFS referral cache Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 2/6] cifs: Get rid of kstrdup_const()'d paths Paulo Alcantara (SUSE)
@ 2019-12-04 20:38 ` Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 4/6] cifs: Merge is_path_valid() into get_normalized_path() Paulo Alcantara (SUSE)
` (3 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:38 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE), Aurelien Aptel
Add helpers for finding TCP connections that are good candidates for
being used by DFS refresh worker.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
---
fs/cifs/dfs_cache.c | 44 +++++++++++++++++++++++++++++++-------------
1 file changed, 31 insertions(+), 13 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index 49c5f045270f..e889608e5e13 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -1305,6 +1305,30 @@ static char *get_dfs_root(const char *path)
return npath;
}
+static inline void put_tcp_server(struct TCP_Server_Info *server)
+{
+ cifs_put_tcp_session(server, 0);
+}
+
+static struct TCP_Server_Info *get_tcp_server(struct smb_vol *vol)
+{
+ struct TCP_Server_Info *server;
+
+ server = cifs_find_tcp_session(vol);
+ if (IS_ERR_OR_NULL(server))
+ return NULL;
+
+ spin_lock(&GlobalMid_Lock);
+ if (server->tcpStatus != CifsGood) {
+ spin_unlock(&GlobalMid_Lock);
+ put_tcp_server(server);
+ return NULL;
+ }
+ spin_unlock(&GlobalMid_Lock);
+
+ return server;
+}
+
/* Find root SMB session out of a DFS link path */
static struct cifs_ses *find_root_ses(struct vol_info *vi,
struct cifs_tcon *tcon,
@@ -1347,13 +1371,8 @@ static struct cifs_ses *find_root_ses(struct vol_info *vi,
goto out;
}
- server = cifs_find_tcp_session(&vol);
- if (IS_ERR_OR_NULL(server)) {
- ses = ERR_PTR(-EHOSTDOWN);
- goto out;
- }
- if (server->tcpStatus != CifsGood) {
- cifs_put_tcp_session(server, 0);
+ server = get_tcp_server(&vol);
+ if (!server) {
ses = ERR_PTR(-EHOSTDOWN);
goto out;
}
@@ -1451,19 +1470,18 @@ static void refresh_cache_worker(struct work_struct *work)
mutex_lock(&vol_lock);
list_for_each_entry(vi, &vol_list, list) {
- server = cifs_find_tcp_session(&vi->smb_vol);
- if (IS_ERR_OR_NULL(server))
+ server = get_tcp_server(&vi->smb_vol);
+ if (!server)
continue;
- if (server->tcpStatus != CifsGood)
- goto next;
+
get_tcons(server, &list);
list_for_each_entry_safe(tcon, ntcon, &list, ulist) {
refresh_tcon(vi, tcon);
list_del_init(&tcon->ulist);
cifs_put_tcon(tcon);
}
-next:
- cifs_put_tcp_session(server, 0);
+
+ put_tcp_server(server);
}
queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
mutex_unlock(&vol_lock);
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 4/6] cifs: Merge is_path_valid() into get_normalized_path()
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
` (2 preceding siblings ...)
2019-12-04 20:38 ` [PATCH v4 3/6] cifs: Introduce helpers for finding TCP connection Paulo Alcantara (SUSE)
@ 2019-12-04 20:38 ` Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 5/6] cifs: Fix potential deadlock when updating vol in cifs_reconnect() Paulo Alcantara (SUSE)
` (2 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:38 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE), Aurelien Aptel
Just do the trivial path validation in get_normalized_path().
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
---
fs/cifs/dfs_cache.c | 21 ++++-----------------
1 file changed, 4 insertions(+), 17 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index e889608e5e13..1d1f7c03931b 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -75,13 +75,11 @@ static void refresh_cache_worker(struct work_struct *work);
static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
-static inline bool is_path_valid(const char *path)
+static int get_normalized_path(const char *path, char **npath)
{
- return path && (strchr(path + 1, '\\') || strchr(path + 1, '/'));
-}
+ if (!path || strlen(path) < 3 || (*path != '\\' && *path != '/'))
+ return -EINVAL;
-static inline int get_normalized_path(const char *path, char **npath)
-{
if (*path == '\\') {
*npath = (char *)path;
} else {
@@ -828,9 +826,6 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
char *npath;
struct cache_entry *ce;
- if (unlikely(!is_path_valid(path)))
- return -EINVAL;
-
rc = get_normalized_path(path, &npath);
if (rc)
return rc;
@@ -875,9 +870,6 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
char *npath;
struct cache_entry *ce;
- if (unlikely(!is_path_valid(path)))
- return -EINVAL;
-
rc = get_normalized_path(path, &npath);
if (rc)
return rc;
@@ -929,9 +921,6 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
struct cache_entry *ce;
struct cache_dfs_tgt *t;
- if (unlikely(!is_path_valid(path)))
- return -EINVAL;
-
rc = get_normalized_path(path, &npath);
if (rc)
return rc;
@@ -989,7 +978,7 @@ int dfs_cache_noreq_update_tgthint(const char *path,
struct cache_entry *ce;
struct cache_dfs_tgt *t;
- if (unlikely(!is_path_valid(path)) || !it)
+ if (!it)
return -EINVAL;
rc = get_normalized_path(path, &npath);
@@ -1049,8 +1038,6 @@ int dfs_cache_get_tgt_referral(const char *path,
if (!it || !ref)
return -EINVAL;
- if (unlikely(!is_path_valid(path)))
- return -EINVAL;
rc = get_normalized_path(path, &npath);
if (rc)
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 5/6] cifs: Fix potential deadlock when updating vol in cifs_reconnect()
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
` (3 preceding siblings ...)
2019-12-04 20:38 ` [PATCH v4 4/6] cifs: Merge is_path_valid() into get_normalized_path() Paulo Alcantara (SUSE)
@ 2019-12-04 20:38 ` Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 6/6] cifs: Avoid doing network I/O while holding cache lock Paulo Alcantara (SUSE)
2020-01-15 21:08 ` [PATCH v4 0/6] DFS fixes Steve French
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:38 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE)
We can't acquire volume lock while refreshing the DFS cache because
cifs_reconnect() may call dfs_cache_update_vol() while we are walking
through the volume list.
To prevent that, make vol_info refcounted, create a temp list with all
volumes eligible for refreshing, and then use it without any locks
held.
Besides, replace vol_lock with a spinlock and protect cache_ttl from
concurrent accesses or changes.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
---
fs/cifs/dfs_cache.c | 109 +++++++++++++++++++++++++++++++-------------
1 file changed, 77 insertions(+), 32 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index 1d1f7c03931b..82c5d9a31f9e 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -49,15 +49,20 @@ struct cache_entry {
struct vol_info {
char *fullpath;
+ spinlock_t smb_vol_lock;
struct smb_vol smb_vol;
char *mntdata;
struct list_head list;
+ struct list_head rlist;
+ struct kref refcnt;
};
static struct kmem_cache *cache_slab __read_mostly;
static struct workqueue_struct *dfscache_wq __read_mostly;
static int cache_ttl;
+static DEFINE_SPINLOCK(cache_ttl_lock);
+
static struct nls_table *cache_nlsc;
/*
@@ -69,7 +74,7 @@ static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
static DEFINE_MUTEX(list_lock);
static LIST_HEAD(vol_list);
-static DEFINE_MUTEX(vol_lock);
+static DEFINE_SPINLOCK(vol_list_lock);
static void refresh_cache_worker(struct work_struct *work);
@@ -300,7 +305,6 @@ int dfs_cache_init(void)
for (i = 0; i < CACHE_HTABLE_SIZE; i++)
INIT_HLIST_HEAD(&cache_htable[i]);
- cache_ttl = -1;
cache_nlsc = load_nls_default();
cifs_dbg(FYI, "%s: initialized DFS referral cache\n", __func__);
@@ -471,15 +475,15 @@ add_cache_entry(unsigned int hash, const char *path,
hlist_add_head_rcu(&ce->hlist, &cache_htable[hash]);
- mutex_lock(&vol_lock);
- if (cache_ttl < 0) {
+ spin_lock(&cache_ttl_lock);
+ if (!cache_ttl) {
cache_ttl = ce->ttl;
queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
} else {
cache_ttl = min_t(int, cache_ttl, ce->ttl);
mod_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
}
- mutex_unlock(&vol_lock);
+ spin_unlock(&cache_ttl_lock);
return ce;
}
@@ -523,21 +527,32 @@ static inline void destroy_slab_cache(void)
kmem_cache_destroy(cache_slab);
}
-static inline void free_vol(struct vol_info *vi)
+static void __vol_release(struct vol_info *vi)
{
- list_del(&vi->list);
kfree(vi->fullpath);
kfree(vi->mntdata);
cifs_cleanup_volume_info_contents(&vi->smb_vol);
kfree(vi);
}
+static void vol_release(struct kref *kref)
+{
+ struct vol_info *vi = container_of(kref, struct vol_info, refcnt);
+
+ spin_lock(&vol_list_lock);
+ list_del(&vi->list);
+ spin_unlock(&vol_list_lock);
+ __vol_release(vi);
+}
+
static inline void free_vol_list(void)
{
struct vol_info *vi, *nvi;
- list_for_each_entry_safe(vi, nvi, &vol_list, list)
- free_vol(vi);
+ list_for_each_entry_safe(vi, nvi, &vol_list, list) {
+ list_del_init(&vi->list);
+ __vol_release(vi);
+ }
}
/**
@@ -1156,10 +1171,13 @@ int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol, const char *fullpath)
goto err_free_fullpath;
vi->mntdata = mntdata;
+ spin_lock_init(&vi->smb_vol_lock);
+ kref_init(&vi->refcnt);
- mutex_lock(&vol_lock);
+ spin_lock(&vol_list_lock);
list_add_tail(&vi->list, &vol_list);
- mutex_unlock(&vol_lock);
+ spin_unlock(&vol_list_lock);
+
return 0;
err_free_fullpath:
@@ -1169,7 +1187,8 @@ int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol, const char *fullpath)
return rc;
}
-static inline struct vol_info *find_vol(const char *fullpath)
+/* Must be called with vol_list_lock held */
+static struct vol_info *find_vol(const char *fullpath)
{
struct vol_info *vi;
@@ -1191,7 +1210,6 @@ static inline struct vol_info *find_vol(const char *fullpath)
*/
int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
{
- int rc;
struct vol_info *vi;
if (!fullpath || !server)
@@ -1199,22 +1217,24 @@ int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
- mutex_lock(&vol_lock);
-
+ spin_lock(&vol_list_lock);
vi = find_vol(fullpath);
if (IS_ERR(vi)) {
- rc = PTR_ERR(vi);
- goto out;
+ spin_unlock(&vol_list_lock);
+ return PTR_ERR(vi);
}
+ kref_get(&vi->refcnt);
+ spin_unlock(&vol_list_lock);
cifs_dbg(FYI, "%s: updating volume info\n", __func__);
+ spin_lock(&vi->smb_vol_lock);
memcpy(&vi->smb_vol.dstaddr, &server->dstaddr,
sizeof(vi->smb_vol.dstaddr));
- rc = 0;
+ spin_unlock(&vi->smb_vol_lock);
-out:
- mutex_unlock(&vol_lock);
- return rc;
+ kref_put(&vi->refcnt, vol_release);
+
+ return 0;
}
/**
@@ -1231,11 +1251,11 @@ void dfs_cache_del_vol(const char *fullpath)
cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
- mutex_lock(&vol_lock);
+ spin_lock(&vol_list_lock);
vi = find_vol(fullpath);
- if (!IS_ERR(vi))
- free_vol(vi);
- mutex_unlock(&vol_lock);
+ spin_unlock(&vol_list_lock);
+
+ kref_put(&vi->refcnt, vol_release);
}
/* Get all tcons that are within a DFS namespace and can be refreshed */
@@ -1449,27 +1469,52 @@ static void refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
*/
static void refresh_cache_worker(struct work_struct *work)
{
- struct vol_info *vi;
+ struct vol_info *vi, *nvi;
struct TCP_Server_Info *server;
- LIST_HEAD(list);
+ LIST_HEAD(vols);
+ LIST_HEAD(tcons);
struct cifs_tcon *tcon, *ntcon;
- mutex_lock(&vol_lock);
-
+ /*
+ * Find SMB volumes that are eligible (server->tcpStatus == CifsGood)
+ * for refreshing.
+ */
+ spin_lock(&vol_list_lock);
list_for_each_entry(vi, &vol_list, list) {
server = get_tcp_server(&vi->smb_vol);
if (!server)
continue;
- get_tcons(server, &list);
- list_for_each_entry_safe(tcon, ntcon, &list, ulist) {
+ kref_get(&vi->refcnt);
+ list_add_tail(&vi->rlist, &vols);
+ put_tcp_server(server);
+ }
+ spin_unlock(&vol_list_lock);
+
+ /* Walk through all TCONs and refresh any expired cache entry */
+ list_for_each_entry_safe(vi, nvi, &vols, rlist) {
+ spin_lock(&vi->smb_vol_lock);
+ server = get_tcp_server(&vi->smb_vol);
+ spin_unlock(&vi->smb_vol_lock);
+
+ if (!server)
+ goto next_vol;
+
+ get_tcons(server, &tcons);
+ list_for_each_entry_safe(tcon, ntcon, &tcons, ulist) {
refresh_tcon(vi, tcon);
list_del_init(&tcon->ulist);
cifs_put_tcon(tcon);
}
put_tcp_server(server);
+
+next_vol:
+ list_del_init(&vi->rlist);
+ kref_put(&vi->refcnt, vol_release);
}
+
+ spin_lock(&cache_ttl_lock);
queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
- mutex_unlock(&vol_lock);
+ spin_unlock(&cache_ttl_lock);
}
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v4 6/6] cifs: Avoid doing network I/O while holding cache lock
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
` (4 preceding siblings ...)
2019-12-04 20:38 ` [PATCH v4 5/6] cifs: Fix potential deadlock when updating vol in cifs_reconnect() Paulo Alcantara (SUSE)
@ 2019-12-04 20:38 ` Paulo Alcantara (SUSE)
2020-01-15 21:08 ` [PATCH v4 0/6] DFS fixes Steve French
6 siblings, 0 replies; 8+ messages in thread
From: Paulo Alcantara (SUSE) @ 2019-12-04 20:38 UTC (permalink / raw)
To: smfrench; +Cc: linux-cifs, Paulo Alcantara (SUSE)
When creating or updating a cache entry, we need to get an DFS
referral (get_dfs_referral), so avoid holding any locks during such
network operation.
To prevent that, do the following:
* change cache hashtable sync method from RCU sync to a read/write
lock.
* use GFP_ATOMIC in memory allocations.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
---
fs/cifs/dfs_cache.c | 547 +++++++++++++++++++++++---------------------
1 file changed, 283 insertions(+), 264 deletions(-)
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index 82c5d9a31f9e..76ffe12d64f5 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -5,8 +5,6 @@
* Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
*/
-#include <linux/rcupdate.h>
-#include <linux/rculist.h>
#include <linux/jhash.h>
#include <linux/ktime.h>
#include <linux/slab.h>
@@ -44,7 +42,6 @@ struct cache_entry {
int numtgts;
struct list_head tlist;
struct cache_dfs_tgt *tgthint;
- struct rcu_head rcu;
};
struct vol_info {
@@ -68,10 +65,10 @@ static struct nls_table *cache_nlsc;
/*
* Number of entries in the cache
*/
-static size_t cache_count;
+static atomic_t cache_count;
static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
-static DEFINE_MUTEX(list_lock);
+static DECLARE_RWSEM(htable_rw_lock);
static LIST_HEAD(vol_list);
static DEFINE_SPINLOCK(vol_list_lock);
@@ -121,38 +118,29 @@ static inline void free_tgts(struct cache_entry *ce)
}
}
-static void free_cache_entry(struct rcu_head *rcu)
-{
- struct cache_entry *ce = container_of(rcu, struct cache_entry, rcu);
-
- kmem_cache_free(cache_slab, ce);
-}
-
static inline void flush_cache_ent(struct cache_entry *ce)
{
- if (hlist_unhashed(&ce->hlist))
- return;
-
- hlist_del_init_rcu(&ce->hlist);
+ hlist_del_init(&ce->hlist);
kfree(ce->path);
free_tgts(ce);
- cache_count--;
- call_rcu(&ce->rcu, free_cache_entry);
+ atomic_dec(&cache_count);
+ kmem_cache_free(cache_slab, ce);
}
static void flush_cache_ents(void)
{
int i;
- rcu_read_lock();
for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
struct hlist_head *l = &cache_htable[i];
+ struct hlist_node *n;
struct cache_entry *ce;
- hlist_for_each_entry_rcu(ce, l, hlist)
- flush_cache_ent(ce);
+ hlist_for_each_entry_safe(ce, n, l, hlist) {
+ if (!hlist_unhashed(&ce->hlist))
+ flush_cache_ent(ce);
+ }
}
- rcu_read_unlock();
}
/*
@@ -160,36 +148,39 @@ static void flush_cache_ents(void)
*/
static int dfscache_proc_show(struct seq_file *m, void *v)
{
- int bucket;
+ int i;
struct cache_entry *ce;
struct cache_dfs_tgt *t;
seq_puts(m, "DFS cache\n---------\n");
- mutex_lock(&list_lock);
-
- rcu_read_lock();
- hash_for_each_rcu(cache_htable, bucket, ce, hlist) {
- seq_printf(m,
- "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
- "interlink=%s,path_consumed=%d,expired=%s\n",
- ce->path,
- ce->srvtype == DFS_TYPE_ROOT ? "root" : "link",
- ce->ttl, ce->etime.tv_nsec,
- IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
- ce->path_consumed,
- cache_entry_expired(ce) ? "yes" : "no");
-
- list_for_each_entry(t, &ce->tlist, list) {
- seq_printf(m, " %s%s\n",
- t->name,
- ce->tgthint == t ? " (target hint)" : "");
- }
+ down_read(&htable_rw_lock);
+ for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+ struct hlist_head *l = &cache_htable[i];
+ hlist_for_each_entry(ce, l, hlist) {
+ if (hlist_unhashed(&ce->hlist))
+ continue;
+
+ seq_printf(m,
+ "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
+ "interlink=%s,path_consumed=%d,expired=%s\n",
+ ce->path,
+ ce->srvtype == DFS_TYPE_ROOT ? "root" : "link",
+ ce->ttl, ce->etime.tv_nsec,
+ IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
+ ce->path_consumed,
+ cache_entry_expired(ce) ? "yes" : "no");
+
+ list_for_each_entry(t, &ce->tlist, list) {
+ seq_printf(m, " %s%s\n",
+ t->name,
+ ce->tgthint == t ? " (target hint)" : "");
+ }
+ }
}
- rcu_read_unlock();
+ up_read(&htable_rw_lock);
- mutex_unlock(&list_lock);
return 0;
}
@@ -207,9 +198,10 @@ static ssize_t dfscache_proc_write(struct file *file, const char __user *buffer,
return -EINVAL;
cifs_dbg(FYI, "clearing dfs cache");
- mutex_lock(&list_lock);
+
+ down_write(&htable_rw_lock);
flush_cache_ents();
- mutex_unlock(&list_lock);
+ up_write(&htable_rw_lock);
return count;
}
@@ -305,6 +297,7 @@ int dfs_cache_init(void)
for (i = 0; i < CACHE_HTABLE_SIZE; i++)
INIT_HLIST_HEAD(&cache_htable[i]);
+ atomic_set(&cache_count, 0);
cache_nlsc = load_nls_default();
cifs_dbg(FYI, "%s: initialized DFS referral cache\n", __func__);
@@ -356,14 +349,14 @@ static inline struct timespec64 get_expire_time(int ttl)
}
/* Allocate a new DFS target */
-static inline struct cache_dfs_tgt *alloc_tgt(const char *name)
+static struct cache_dfs_tgt *alloc_target(const char *name)
{
struct cache_dfs_tgt *t;
- t = kmalloc(sizeof(*t), GFP_KERNEL);
+ t = kmalloc(sizeof(*t), GFP_ATOMIC);
if (!t)
return ERR_PTR(-ENOMEM);
- t->name = kstrndup(name, strlen(name), GFP_KERNEL);
+ t->name = kstrndup(name, strlen(name), GFP_ATOMIC);
if (!t->name) {
kfree(t);
return ERR_PTR(-ENOMEM);
@@ -390,7 +383,7 @@ static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs,
for (i = 0; i < numrefs; i++) {
struct cache_dfs_tgt *t;
- t = alloc_tgt(refs[i].node_name);
+ t = alloc_target(refs[i].node_name);
if (IS_ERR(t)) {
free_tgts(ce);
return PTR_ERR(t);
@@ -439,41 +432,44 @@ static struct cache_entry *alloc_cache_entry(const char *path,
return ce;
}
+/* Must be called with htable_rw_lock held */
static void remove_oldest_entry(void)
{
- int bucket;
+ int i;
struct cache_entry *ce;
struct cache_entry *to_del = NULL;
- rcu_read_lock();
- hash_for_each_rcu(cache_htable, bucket, ce, hlist) {
- if (!to_del || timespec64_compare(&ce->etime,
- &to_del->etime) < 0)
- to_del = ce;
+ for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+ struct hlist_head *l = &cache_htable[i];
+
+ hlist_for_each_entry(ce, l, hlist) {
+ if (hlist_unhashed(&ce->hlist))
+ continue;
+ if (!to_del || timespec64_compare(&ce->etime,
+ &to_del->etime) < 0)
+ to_del = ce;
+ }
}
+
if (!to_del) {
cifs_dbg(FYI, "%s: no entry to remove", __func__);
- goto out;
+ return;
}
+
cifs_dbg(FYI, "%s: removing entry", __func__);
dump_ce(to_del);
flush_cache_ent(to_del);
-out:
- rcu_read_unlock();
}
/* Add a new DFS cache entry */
-static inline struct cache_entry *
-add_cache_entry(unsigned int hash, const char *path,
- const struct dfs_info3_param *refs, int numrefs)
+static int add_cache_entry(const char *path, unsigned int hash,
+ struct dfs_info3_param *refs, int numrefs)
{
struct cache_entry *ce;
ce = alloc_cache_entry(path, refs, numrefs);
if (IS_ERR(ce))
- return ce;
-
- hlist_add_head_rcu(&ce->hlist, &cache_htable[hash]);
+ return PTR_ERR(ce);
spin_lock(&cache_ttl_lock);
if (!cache_ttl) {
@@ -485,13 +481,20 @@ add_cache_entry(unsigned int hash, const char *path,
}
spin_unlock(&cache_ttl_lock);
- return ce;
+ down_write(&htable_rw_lock);
+ hlist_add_head(&ce->hlist, &cache_htable[hash]);
+ dump_ce(ce);
+ up_write(&htable_rw_lock);
+
+ return 0;
}
/*
* Find a DFS cache entry in hash table and optionally check prefix path against
* @path.
* Use whole path components in the match.
+ * Must be called with htable_rw_lock held.
+ *
* Return ERR_PTR(-ENOENT) if the entry is not found.
*/
static struct cache_entry *lookup_cache_entry(const char *path,
@@ -503,15 +506,13 @@ static struct cache_entry *lookup_cache_entry(const char *path,
h = cache_entry_hash(path, strlen(path));
- rcu_read_lock();
- hlist_for_each_entry_rcu(ce, &cache_htable[h], hlist) {
+ hlist_for_each_entry(ce, &cache_htable[h], hlist) {
if (!strcasecmp(path, ce->path)) {
found = true;
dump_ce(ce);
break;
}
}
- rcu_read_unlock();
if (!found)
ce = ERR_PTR(-ENOENT);
@@ -521,12 +522,6 @@ static struct cache_entry *lookup_cache_entry(const char *path,
return ce;
}
-static inline void destroy_slab_cache(void)
-{
- rcu_barrier();
- kmem_cache_destroy(cache_slab);
-}
-
static void __vol_release(struct vol_info *vi)
{
kfree(vi->fullpath);
@@ -564,77 +559,74 @@ void dfs_cache_destroy(void)
unload_nls(cache_nlsc);
free_vol_list();
flush_cache_ents();
- destroy_slab_cache();
+ kmem_cache_destroy(cache_slab);
destroy_workqueue(dfscache_wq);
cifs_dbg(FYI, "%s: destroyed DFS referral cache\n", __func__);
}
-static inline struct cache_entry *
-__update_cache_entry(const char *path, const struct dfs_info3_param *refs,
- int numrefs)
+/* Must be called with htable_rw_lock held */
+static int __update_cache_entry(const char *path,
+ const struct dfs_info3_param *refs,
+ int numrefs)
{
int rc;
- unsigned int h;
struct cache_entry *ce;
char *s, *th = NULL;
- ce = lookup_cache_entry(path, &h);
+ ce = lookup_cache_entry(path, NULL);
if (IS_ERR(ce))
- return ce;
+ return PTR_ERR(ce);
if (ce->tgthint) {
s = ce->tgthint->name;
- th = kstrndup(s, strlen(s), GFP_KERNEL);
+ th = kstrndup(s, strlen(s), GFP_ATOMIC);
if (!th)
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
}
free_tgts(ce);
ce->numtgts = 0;
rc = copy_ref_data(refs, numrefs, ce, th);
- kfree(th);
- if (rc)
- ce = ERR_PTR(rc);
+ kfree(th);
- return ce;
+ return 0;
}
-/* Update an expired cache entry by getting a new DFS referral from server */
-static struct cache_entry *
-update_cache_entry(const unsigned int xid, struct cifs_ses *ses,
- const struct nls_table *nls_codepage, int remap,
- const char *path, struct cache_entry *ce)
+static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
+ const struct nls_table *nls_codepage, int remap,
+ const char *path, struct dfs_info3_param **refs,
+ int *numrefs)
{
- int rc;
- struct dfs_info3_param *refs = NULL;
- int numrefs = 0;
+ cifs_dbg(FYI, "%s: get an DFS referral for %s\n", __func__, path);
- cifs_dbg(FYI, "%s: update expired cache entry\n", __func__);
- /*
- * Check if caller provided enough parameters to update an expired
- * entry.
- */
if (!ses || !ses->server || !ses->server->ops->get_dfs_refer)
- return ERR_PTR(-ETIME);
+ return -EOPNOTSUPP;
if (unlikely(!nls_codepage))
- return ERR_PTR(-ETIME);
+ return -EINVAL;
- cifs_dbg(FYI, "%s: DFS referral request for %s\n", __func__, path);
+ *refs = NULL;
+ *numrefs = 0;
- rc = ses->server->ops->get_dfs_refer(xid, ses, path, &refs, &numrefs,
- nls_codepage, remap);
- if (rc)
- ce = ERR_PTR(rc);
- else
- ce = __update_cache_entry(path, refs, numrefs);
+ return ses->server->ops->get_dfs_refer(xid, ses, path, refs, numrefs,
+ nls_codepage, remap);
+}
- dump_refs(refs, numrefs);
- free_dfs_info_array(refs, numrefs);
+/* Update an expired cache entry by getting a new DFS referral from server */
+static int update_cache_entry(const char *path,
+ const struct dfs_info3_param *refs,
+ int numrefs)
+{
- return ce;
+ int rc;
+
+ down_write(&htable_rw_lock);
+ rc = __update_cache_entry(path, refs, numrefs);
+ up_write(&htable_rw_lock);
+
+ return rc;
}
/*
@@ -646,95 +638,86 @@ update_cache_entry(const unsigned int xid, struct cifs_ses *ses,
* For interlinks, __cifs_dfs_mount() and expand_dfs_referral() are supposed to
* handle them properly.
*/
-static struct cache_entry *
-do_dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
- const struct nls_table *nls_codepage, int remap,
- const char *path, bool noreq)
+static int __dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
+ const struct nls_table *nls_codepage, int remap,
+ const char *path, bool noreq)
{
int rc;
- unsigned int h;
+ unsigned int hash;
struct cache_entry *ce;
- struct dfs_info3_param *nrefs;
- int numnrefs;
+ struct dfs_info3_param *refs = NULL;
+ int numrefs = 0;
+ bool newent = false;
cifs_dbg(FYI, "%s: search path: %s\n", __func__, path);
- ce = lookup_cache_entry(path, &h);
- if (IS_ERR(ce)) {
- cifs_dbg(FYI, "%s: cache miss\n", __func__);
- /*
- * If @noreq is set, no requests will be sent to the server for
- * either updating or getting a new DFS referral.
- */
- if (noreq)
- return ce;
- /*
- * No cache entry was found, so check for valid parameters that
- * will be required to get a new DFS referral and then create a
- * new cache entry.
- */
- if (!ses || !ses->server || !ses->server->ops->get_dfs_refer) {
- ce = ERR_PTR(-EOPNOTSUPP);
- return ce;
- }
- if (unlikely(!nls_codepage)) {
- ce = ERR_PTR(-EINVAL);
- return ce;
- }
+ down_read(&htable_rw_lock);
- nrefs = NULL;
- numnrefs = 0;
+ ce = lookup_cache_entry(path, &hash);
- cifs_dbg(FYI, "%s: DFS referral request for %s\n", __func__,
- path);
+ /*
+ * If @noreq is set, no requests will be sent to the server. Just return
+ * the cache entry.
+ */
+ if (noreq) {
+ up_read(&htable_rw_lock);
+ return IS_ERR(ce) ? PTR_ERR(ce) : 0;
+ }
- rc = ses->server->ops->get_dfs_refer(xid, ses, path, &nrefs,
- &numnrefs, nls_codepage,
- remap);
- if (rc) {
- ce = ERR_PTR(rc);
- return ce;
+ if (!IS_ERR(ce)) {
+ if (!cache_entry_expired(ce)) {
+ dump_ce(ce);
+ up_read(&htable_rw_lock);
+ return 0;
}
+ } else {
+ newent = true;
+ }
- dump_refs(nrefs, numnrefs);
+ up_read(&htable_rw_lock);
- cifs_dbg(FYI, "%s: new cache entry\n", __func__);
+ /*
+ * No entry was found.
+ *
+ * Request a new DFS referral in order to create a new cache entry, or
+ * updating an existing one.
+ */
+ rc = get_dfs_referral(xid, ses, nls_codepage, remap, path,
+ &refs, &numrefs);
+ if (rc)
+ return rc;
- if (cache_count >= CACHE_MAX_ENTRIES) {
- cifs_dbg(FYI, "%s: reached max cache size (%d)",
- __func__, CACHE_MAX_ENTRIES);
- remove_oldest_entry();
- }
- ce = add_cache_entry(h, path, nrefs, numnrefs);
- free_dfs_info_array(nrefs, numnrefs);
+ dump_refs(refs, numrefs);
- if (IS_ERR(ce))
- return ce;
+ if (!newent) {
+ rc = update_cache_entry(path, refs, numrefs);
+ goto out_free_refs;
+ }
- cache_count++;
+ if (atomic_read(&cache_count) >= CACHE_MAX_ENTRIES) {
+ cifs_dbg(FYI, "%s: reached max cache size (%d)", __func__,
+ CACHE_MAX_ENTRIES);
+ down_write(&htable_rw_lock);
+ remove_oldest_entry();
+ up_write(&htable_rw_lock);
}
- dump_ce(ce);
+ rc = add_cache_entry(path, hash, refs, numrefs);
+ if (!rc)
+ atomic_inc(&cache_count);
- /* Just return the found cache entry in case @noreq is set */
- if (noreq)
- return ce;
-
- if (cache_entry_expired(ce)) {
- cifs_dbg(FYI, "%s: expired cache entry\n", __func__);
- ce = update_cache_entry(xid, ses, nls_codepage, remap, path,
- ce);
- if (IS_ERR(ce)) {
- cifs_dbg(FYI, "%s: failed to update expired entry\n",
- __func__);
- }
- }
- return ce;
+out_free_refs:
+ free_dfs_info_array(refs, numrefs);
+ return rc;
}
-/* Set up a new DFS referral from a given cache entry */
-static int setup_ref(const char *path, const struct cache_entry *ce,
- struct dfs_info3_param *ref, const char *tgt)
+/*
+ * Set up a DFS referral from a given cache entry.
+ *
+ * Must be called with htable_rw_lock held.
+ */
+static int setup_referral(const char *path, struct cache_entry *ce,
+ struct dfs_info3_param *ref, const char *target)
{
int rc;
@@ -742,18 +725,17 @@ static int setup_ref(const char *path, const struct cache_entry *ce,
memset(ref, 0, sizeof(*ref));
- ref->path_name = kstrndup(path, strlen(path), GFP_KERNEL);
+ ref->path_name = kstrndup(path, strlen(path), GFP_ATOMIC);
if (!ref->path_name)
return -ENOMEM;
- ref->path_consumed = ce->path_consumed;
-
- ref->node_name = kstrndup(tgt, strlen(tgt), GFP_KERNEL);
+ ref->node_name = kstrndup(target, strlen(target), GFP_ATOMIC);
if (!ref->node_name) {
rc = -ENOMEM;
goto err_free_path;
}
+ ref->path_consumed = ce->path_consumed;
ref->ttl = ce->ttl;
ref->server_type = ce->srvtype;
ref->ref_flag = ce->flags;
@@ -767,8 +749,7 @@ static int setup_ref(const char *path, const struct cache_entry *ce,
}
/* Return target list of a DFS cache entry */
-static int get_tgt_list(const struct cache_entry *ce,
- struct dfs_cache_tgt_list *tl)
+static int get_targets(struct cache_entry *ce, struct dfs_cache_tgt_list *tl)
{
int rc;
struct list_head *head = &tl->tl_list;
@@ -779,14 +760,13 @@ static int get_tgt_list(const struct cache_entry *ce,
INIT_LIST_HEAD(head);
list_for_each_entry(t, &ce->tlist, list) {
- it = kzalloc(sizeof(*it), GFP_KERNEL);
+ it = kzalloc(sizeof(*it), GFP_ATOMIC);
if (!it) {
rc = -ENOMEM;
goto err_free_it;
}
- it->it_name = kstrndup(t->name, strlen(t->name),
- GFP_KERNEL);
+ it->it_name = kstrndup(t->name, strlen(t->name), GFP_ATOMIC);
if (!it->it_name) {
kfree(it);
rc = -ENOMEM;
@@ -798,6 +778,7 @@ static int get_tgt_list(const struct cache_entry *ce,
else
list_add_tail(&it->it_list, head);
}
+
tl->tl_numtgts = ce->numtgts;
return 0;
@@ -845,19 +826,29 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
if (rc)
return rc;
- mutex_lock(&list_lock);
- ce = do_dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
- if (!IS_ERR(ce)) {
- if (ref)
- rc = setup_ref(path, ce, ref, get_tgt_name(ce));
- else
- rc = 0;
- if (!rc && tgt_list)
- rc = get_tgt_list(ce, tgt_list);
- } else {
+ rc = __dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
+ if (rc)
+ goto out_free_path;
+
+ down_read(&htable_rw_lock);
+
+ ce = lookup_cache_entry(npath, NULL);
+ if (IS_ERR(ce)) {
+ up_read(&htable_rw_lock);
rc = PTR_ERR(ce);
+ goto out_free_path;
}
- mutex_unlock(&list_lock);
+
+ if (ref)
+ rc = setup_referral(path, ce, ref, get_tgt_name(ce));
+ else
+ rc = 0;
+ if (!rc && tgt_list)
+ rc = get_targets(ce, tgt_list);
+
+ up_read(&htable_rw_lock);
+
+out_free_path:
free_normalized_path(path, npath);
return rc;
}
@@ -889,22 +880,27 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
if (rc)
return rc;
- mutex_lock(&list_lock);
- ce = do_dfs_cache_find(0, NULL, NULL, 0, npath, true);
+ cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
+
+ down_read(&htable_rw_lock);
+
+ ce = lookup_cache_entry(npath, NULL);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
- goto out;
+ goto out_unlock;
}
if (ref)
- rc = setup_ref(path, ce, ref, get_tgt_name(ce));
+ rc = setup_referral(path, ce, ref, get_tgt_name(ce));
else
rc = 0;
if (!rc && tgt_list)
- rc = get_tgt_list(ce, tgt_list);
-out:
- mutex_unlock(&list_lock);
+ rc = get_targets(ce, tgt_list);
+
+out_unlock:
+ up_read(&htable_rw_lock);
free_normalized_path(path, npath);
+
return rc;
}
@@ -940,21 +936,24 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
if (rc)
return rc;
- cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
+ cifs_dbg(FYI, "%s: update target hint - path: %s\n", __func__, npath);
+
+ rc = __dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
+ if (rc)
+ goto out_free_path;
- mutex_lock(&list_lock);
- ce = do_dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
+ down_write(&htable_rw_lock);
+
+ ce = lookup_cache_entry(npath, NULL);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
- goto out;
+ goto out_unlock;
}
- rc = 0;
-
t = ce->tgthint;
if (likely(!strcasecmp(it->it_name, t->name)))
- goto out;
+ goto out_unlock;
list_for_each_entry(t, &ce->tlist, list) {
if (!strcasecmp(t->name, it->it_name)) {
@@ -965,9 +964,11 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
}
}
-out:
- mutex_unlock(&list_lock);
+out_unlock:
+ up_write(&htable_rw_lock);
+out_free_path:
free_normalized_path(path, npath);
+
return rc;
}
@@ -1002,20 +1003,19 @@ int dfs_cache_noreq_update_tgthint(const char *path,
cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
- mutex_lock(&list_lock);
+ down_write(&htable_rw_lock);
- ce = do_dfs_cache_find(0, NULL, NULL, 0, npath, true);
+ ce = lookup_cache_entry(npath, NULL);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
- goto out;
+ goto out_unlock;
}
rc = 0;
-
t = ce->tgthint;
if (unlikely(!strcasecmp(it->it_name, t->name)))
- goto out;
+ goto out_unlock;
list_for_each_entry(t, &ce->tlist, list) {
if (!strcasecmp(t->name, it->it_name)) {
@@ -1026,9 +1026,10 @@ int dfs_cache_noreq_update_tgthint(const char *path,
}
}
-out:
- mutex_unlock(&list_lock);
+out_unlock:
+ up_write(&htable_rw_lock);
free_normalized_path(path, npath);
+
return rc;
}
@@ -1049,7 +1050,6 @@ int dfs_cache_get_tgt_referral(const char *path,
int rc;
char *npath;
struct cache_entry *ce;
- unsigned int h;
if (!it || !ref)
return -EINVAL;
@@ -1060,21 +1060,22 @@ int dfs_cache_get_tgt_referral(const char *path,
cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
- mutex_lock(&list_lock);
+ down_read(&htable_rw_lock);
- ce = lookup_cache_entry(npath, &h);
+ ce = lookup_cache_entry(npath, NULL);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
- goto out;
+ goto out_unlock;
}
cifs_dbg(FYI, "%s: target name: %s\n", __func__, it->it_name);
- rc = setup_ref(path, ce, ref, it->it_name);
+ rc = setup_referral(path, ce, ref, it->it_name);
-out:
- mutex_unlock(&list_lock);
+out_unlock:
+ up_read(&htable_rw_lock);
free_normalized_path(path, npath);
+
return rc;
}
@@ -1343,6 +1344,7 @@ static struct cifs_ses *find_root_ses(struct vol_info *vi,
{
char *rpath;
int rc;
+ struct cache_entry *ce;
struct dfs_info3_param ref = {0};
char *mdata = NULL, *devname = NULL;
struct TCP_Server_Info *server;
@@ -1353,15 +1355,26 @@ static struct cifs_ses *find_root_ses(struct vol_info *vi,
if (IS_ERR(rpath))
return ERR_CAST(rpath);
- memset(&vol, 0, sizeof(vol));
+ down_read(&htable_rw_lock);
+
+ ce = lookup_cache_entry(rpath, NULL);
+ if (IS_ERR(ce)) {
+ up_read(&htable_rw_lock);
+ ses = ERR_CAST(ce);
+ goto out;
+ }
- rc = dfs_cache_noreq_find(rpath, &ref, NULL);
+ rc = setup_referral(path, ce, &ref, get_tgt_name(ce));
if (rc) {
+ up_read(&htable_rw_lock);
ses = ERR_PTR(rc);
goto out;
}
- mdata = cifs_compose_mount_options(vi->mntdata, rpath, &ref, &devname);
+ up_read(&htable_rw_lock);
+
+ mdata = cifs_compose_mount_options(vi->mntdata, rpath, &ref,
+ &devname);
free_dfs_info_param(&ref);
if (IS_ERR(mdata)) {
@@ -1395,16 +1408,15 @@ static struct cifs_ses *find_root_ses(struct vol_info *vi,
}
/* Refresh DFS cache entry from a given tcon */
-static void refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
+static int refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
{
int rc = 0;
unsigned int xid;
char *path, *npath;
- unsigned int h;
struct cache_entry *ce;
+ struct cifs_ses *root_ses = NULL, *ses;
struct dfs_info3_param *refs = NULL;
int numrefs = 0;
- struct cifs_ses *root_ses = NULL, *ses;
xid = get_xid();
@@ -1412,19 +1424,23 @@ static void refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
rc = get_normalized_path(path, &npath);
if (rc)
- goto out;
+ goto out_free_xid;
- mutex_lock(&list_lock);
- ce = lookup_cache_entry(npath, &h);
- mutex_unlock(&list_lock);
+ down_read(&htable_rw_lock);
+ ce = lookup_cache_entry(npath, NULL);
if (IS_ERR(ce)) {
rc = PTR_ERR(ce);
- goto out;
+ up_read(&htable_rw_lock);
+ goto out_free_path;
}
- if (!cache_entry_expired(ce))
- goto out;
+ if (!cache_entry_expired(ce)) {
+ up_read(&htable_rw_lock);
+ goto out_free_path;
+ }
+
+ up_read(&htable_rw_lock);
/* If it's a DFS Link, then use root SMB session for refreshing it */
if (is_dfs_link(npath)) {
@@ -1432,35 +1448,29 @@ static void refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
if (IS_ERR(ses)) {
rc = PTR_ERR(ses);
root_ses = NULL;
- goto out;
+ goto out_free_path;
}
} else {
ses = tcon->ses;
}
- if (unlikely(!ses->server->ops->get_dfs_refer)) {
- rc = -EOPNOTSUPP;
- } else {
- rc = ses->server->ops->get_dfs_refer(xid, ses, path, &refs,
- &numrefs, cache_nlsc,
- tcon->remap);
- if (!rc) {
- mutex_lock(&list_lock);
- ce = __update_cache_entry(npath, refs, numrefs);
- mutex_unlock(&list_lock);
- dump_refs(refs, numrefs);
- free_dfs_info_array(refs, numrefs);
- if (IS_ERR(ce))
- rc = PTR_ERR(ce);
- }
+ rc = get_dfs_referral(xid, ses, cache_nlsc, tcon->remap, npath, &refs,
+ &numrefs);
+ if (!rc) {
+ dump_refs(refs, numrefs);
+ rc = update_cache_entry(npath, refs, numrefs);
+ free_dfs_info_array(refs, numrefs);
}
-out:
if (root_ses)
cifs_put_smb_ses(root_ses);
- free_xid(xid);
+out_free_path:
free_normalized_path(path, npath);
+
+out_free_xid:
+ free_xid(xid);
+ return rc;
}
/*
@@ -1474,6 +1484,7 @@ static void refresh_cache_worker(struct work_struct *work)
LIST_HEAD(vols);
LIST_HEAD(tcons);
struct cifs_tcon *tcon, *ntcon;
+ int rc;
/*
* Find SMB volumes that are eligible (server->tcpStatus == CifsGood)
@@ -1501,8 +1512,16 @@ static void refresh_cache_worker(struct work_struct *work)
goto next_vol;
get_tcons(server, &tcons);
+ rc = 0;
+
list_for_each_entry_safe(tcon, ntcon, &tcons, ulist) {
- refresh_tcon(vi, tcon);
+ /*
+ * Skip tcp server if any of its tcons failed to refresh
+ * (possibily due to reconnects).
+ */
+ if (!rc)
+ rc = refresh_tcon(vi, tcon);
+
list_del_init(&tcon->ulist);
cifs_put_tcon(tcon);
}
--
2.24.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v4 0/6] DFS fixes
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
` (5 preceding siblings ...)
2019-12-04 20:38 ` [PATCH v4 6/6] cifs: Avoid doing network I/O while holding cache lock Paulo Alcantara (SUSE)
@ 2020-01-15 21:08 ` Steve French
6 siblings, 0 replies; 8+ messages in thread
From: Steve French @ 2020-01-15 21:08 UTC (permalink / raw)
To: Paulo Alcantara (SUSE); +Cc: CIFS
tentatively merged into cifs-2.6.git for-next pending more testing
(buildbot) and review of patches 5 and 6 in the series
On Wed, Dec 4, 2019 at 2:38 PM Paulo Alcantara (SUSE) <pc@cjr.nz> wrote:
>
> Hi,
>
> Follow v4 of DFS fixes and cleanups.
>
> Add kref to vol_info structure and avoid potential races in cache_ttl
> (Aurelien).
>
> Paulo Alcantara (SUSE) (6):
> cifs: Clean up DFS referral cache
> cifs: Get rid of kstrdup_const()'d paths
> cifs: Introduce helpers for finding TCP connection
> cifs: Merge is_path_valid() into get_normalized_path()
> cifs: Fix potential deadlock when updating vol in cifs_reconnect()
> cifs: Avoid doing network I/O while holding cache lock
>
> fs/cifs/dfs_cache.c | 1110 +++++++++++++++++++++++--------------------
> 1 file changed, 586 insertions(+), 524 deletions(-)
>
> --
> 2.24.0
>
--
Thanks,
Steve
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2020-01-15 21:08 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-04 20:37 [PATCH v4 0/6] DFS fixes Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 1/6] cifs: Clean up DFS referral cache Paulo Alcantara (SUSE)
2019-12-04 20:37 ` [PATCH v4 2/6] cifs: Get rid of kstrdup_const()'d paths Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 3/6] cifs: Introduce helpers for finding TCP connection Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 4/6] cifs: Merge is_path_valid() into get_normalized_path() Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 5/6] cifs: Fix potential deadlock when updating vol in cifs_reconnect() Paulo Alcantara (SUSE)
2019-12-04 20:38 ` [PATCH v4 6/6] cifs: Avoid doing network I/O while holding cache lock Paulo Alcantara (SUSE)
2020-01-15 21:08 ` [PATCH v4 0/6] DFS fixes Steve French
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