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reactos/base/services/nfsd/name_cache.c

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/* NFSv4.1 client for Windows
* Copyright © 2012 The Regents of the University of Michigan
*
* Olga Kornievskaia <aglo@umich.edu>
* Casey Bodley <cbodley@umich.edu>
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* without any warranty; without even the implied warranty of merchantability
* or fitness for a particular purpose. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA
*/
#include <windows.h>
#include <strsafe.h>
#include <time.h>
#include <assert.h>
#include "nfs41_ops.h"
#include "nfs41_compound.h"
#include "name_cache.h"
#include "util.h"
#include "tree.h"
#include "daemon_debug.h"
/* dprintf levels for name cache logging */
enum {
NCLVL1 = 2,
NCLVL2
};
#define NAME_CACHE_EXPIRATION 20 /* TODO: get from configuration */
/* allow up to 256K of memory for name and attribute cache entries */
#define NAME_CACHE_MAX_SIZE 262144
/* negative lookup caching
*
* by caching lookups that result in NOENT, we can avoid sending subsequent
* lookups over the wire. a name cache entry is negative when its attributes
* pointer is NULL. negative entries are created by three functions:
* nfs41_name_cache_remove(), _insert() when called with NULL for the fh and
* attributes, and _rename() for the source entry */
/* delegations and cache feedback
*
* delegations provide a guarantee that no links or attributes will change
* without notice. the name cache takes advantage of this by preventing
* delegated entries from being removed on NAME_CACHE_EXPIRATION, though
* they're still removed when a parent is invalidated. the attribute cache
* holds an extra reference on delegated entries to prevent their removal
* entirely, until the delegation is returned.
* this extra reference presents a problem when the number of delegations
* approaches the maximum number of attribute cache entries. when there are
* not enough available entries to store the parent directories, every lookup
* results in a name cache miss, and cache performance degrades significantly.
* the solution is to provide feedback via nfs41_name_cache_insert() when
* delegations reach a certain percent of the cache capacity. the error code
* ERROR_TOO_MANY_OPEN_FILES, chosen arbitrarily for this case, instructs the
* caller to return an outstanding delegation before caching a new one.
*/
static __inline bool_t is_delegation(
IN enum open_delegation_type4 type)
{
return type == OPEN_DELEGATE_READ || type == OPEN_DELEGATE_WRITE;
}
/* attribute cache */
struct attr_cache_entry {
RB_ENTRY(attr_cache_entry) rbnode;
struct list_entry free_entry;
uint64_t change;
uint64_t size;
uint64_t fileid;
int64_t time_access_s;
int64_t time_create_s;
int64_t time_modify_s;
uint32_t time_access_ns;
uint32_t time_create_ns;
uint32_t time_modify_ns;
uint32_t numlinks;
unsigned mode : 30;
unsigned hidden : 1;
unsigned system : 1;
unsigned archive : 1;
time_t expiration;
unsigned ref_count : 26;
unsigned type : 4;
unsigned invalidated : 1;
unsigned delegated : 1;
};
#define ATTR_ENTRY_SIZE sizeof(struct attr_cache_entry)
RB_HEAD(attr_tree, attr_cache_entry);
struct attr_cache {
struct attr_tree head;
struct attr_cache_entry *pool;
struct list_entry free_entries;
};
int attr_cmp(struct attr_cache_entry *lhs, struct attr_cache_entry *rhs)
{
return lhs->fileid < rhs->fileid ? -1 : lhs->fileid > rhs->fileid;
}
RB_GENERATE(attr_tree, attr_cache_entry, rbnode, attr_cmp)
/* attr_cache_entry */
#define attr_entry(pos) list_container(pos, struct attr_cache_entry, free_entry)
static int attr_cache_entry_create(
IN struct attr_cache *cache,
IN uint64_t fileid,
OUT struct attr_cache_entry **entry_out)
{
struct attr_cache_entry *entry;
int status = NO_ERROR;
/* get the next entry from free_entries and remove it */
if (list_empty(&cache->free_entries)) {
status = ERROR_OUTOFMEMORY;
goto out;
}
entry = attr_entry(cache->free_entries.next);
list_remove(&entry->free_entry);
entry->fileid = fileid;
entry->invalidated = FALSE;
entry->delegated = FALSE;
*entry_out = entry;
out:
return status;
}
static __inline void attr_cache_entry_free(
IN struct attr_cache *cache,
IN struct attr_cache_entry *entry)
{
dprintf(NCLVL1, "attr_cache_entry_free(%llu)\n", entry->fileid);
RB_REMOVE(attr_tree, &cache->head, entry);
/* add it back to free_entries */
list_add_tail(&cache->free_entries, &entry->free_entry);
}
static __inline void attr_cache_entry_ref(
IN struct attr_cache *cache,
IN struct attr_cache_entry *entry)
{
const uint32_t previous = entry->ref_count++;
dprintf(NCLVL2, "attr_cache_entry_ref(%llu) %u -> %u\n",
entry->fileid, previous, entry->ref_count);
}
static __inline void attr_cache_entry_deref(
IN struct attr_cache *cache,
IN struct attr_cache_entry *entry)
{
const uint32_t previous = entry->ref_count--;
dprintf(NCLVL2, "attr_cache_entry_deref(%llu) %u -> %u\n",
entry->fileid, previous, entry->ref_count);
if (entry->ref_count == 0)
attr_cache_entry_free(cache, entry);
}
static __inline int attr_cache_entry_expired(
IN const struct attr_cache_entry *entry)
{
return entry->invalidated ||
(!entry->delegated && time(NULL) > entry->expiration);
}
/* attr_cache */
static int attr_cache_init(
IN struct attr_cache *cache,
IN uint32_t max_entries)
{
uint32_t i;
int status = NO_ERROR;
/* allocate a pool of entries */
cache->pool = calloc(max_entries, ATTR_ENTRY_SIZE);
if (cache->pool == NULL) {
status = GetLastError();
goto out;
}
/* initialize the list of free entries */
list_init(&cache->free_entries);
for (i = 0; i < max_entries; i++) {
list_init(&cache->pool[i].free_entry);
list_add_tail(&cache->free_entries, &cache->pool[i].free_entry);
}
out:
return status;
}
static void attr_cache_free(
IN struct attr_cache *cache)
{
/* free the pool */
free(cache->pool);
cache->pool = NULL;
list_init(&cache->free_entries);
}
static struct attr_cache_entry* attr_cache_search(
IN struct attr_cache *cache,
IN uint64_t fileid)
{
/* find an entry that matches fileid */
struct attr_cache_entry tmp;
tmp.fileid = fileid;
return RB_FIND(attr_tree, &cache->head, &tmp);
}
static int attr_cache_insert(
IN struct attr_cache *cache,
IN struct attr_cache_entry *entry)
{
int status = NO_ERROR;
dprintf(NCLVL2, "--> attr_cache_insert(%llu)\n", entry->fileid);
if (RB_INSERT(attr_tree, &cache->head, entry))
status = ERROR_FILE_EXISTS;
dprintf(NCLVL2, "<-- attr_cache_insert() returning %d\n", status);
return status;
}
static int attr_cache_find_or_create(
IN struct attr_cache *cache,
IN uint64_t fileid,
OUT struct attr_cache_entry **entry_out)
{
struct attr_cache_entry *entry;
int status = NO_ERROR;
dprintf(NCLVL1, "--> attr_cache_find_or_create(%llu)\n", fileid);
/* look for an existing entry */
entry = attr_cache_search(cache, fileid);
if (entry == NULL) {
/* create and insert */
status = attr_cache_entry_create(cache, fileid, &entry);
if (status)
goto out;
status = attr_cache_insert(cache, entry);
if (status)
goto out_err_free;
}
/* take a reference on success */
attr_cache_entry_ref(cache, entry);
out:
*entry_out = entry;
dprintf(NCLVL1, "<-- attr_cache_find_or_create() returning %d\n",
status);
return status;
out_err_free:
attr_cache_entry_free(cache, entry);
entry = NULL;
goto out;
}
static void attr_cache_update(
IN struct attr_cache_entry *entry,
IN const nfs41_file_info *info,
IN enum open_delegation_type4 delegation)
{
/* update the attributes present in mask */
if (info->attrmask.count >= 1) {
if (info->attrmask.arr[0] & FATTR4_WORD0_TYPE)
entry->type = (unsigned char)(info->type & NFS_FTYPE_MASK);
if (info->attrmask.arr[0] & FATTR4_WORD0_CHANGE) {
entry->change = info->change;
/* revalidate whenever we get a change attribute */
entry->invalidated = 0;
entry->expiration = time(NULL) + NAME_CACHE_EXPIRATION;
}
if (info->attrmask.arr[0] & FATTR4_WORD0_SIZE)
entry->size = info->size;
if (info->attrmask.arr[0] & FATTR4_WORD0_HIDDEN)
entry->hidden = info->hidden;
if (info->attrmask.arr[0] & FATTR4_WORD0_ARCHIVE)
entry->archive = info->archive;
}
if (info->attrmask.count >= 2) {
if (info->attrmask.arr[1] & FATTR4_WORD1_MODE)
entry->mode = info->mode;
if (info->attrmask.arr[1] & FATTR4_WORD1_NUMLINKS)
entry->numlinks = info->numlinks;
if (info->attrmask.arr[1] & FATTR4_WORD1_TIME_ACCESS) {
entry->time_access_s = info->time_access.seconds;
entry->time_access_ns = info->time_access.nseconds;
}
if (info->attrmask.arr[1] & FATTR4_WORD1_TIME_CREATE) {
entry->time_create_s = info->time_create.seconds;
entry->time_create_ns = info->time_create.nseconds;
}
if (info->attrmask.arr[1] & FATTR4_WORD1_TIME_MODIFY) {
entry->time_modify_s = info->time_modify.seconds;
entry->time_modify_ns = info->time_modify.nseconds;
}
if (info->attrmask.arr[1] & FATTR4_WORD1_SYSTEM)
entry->system = info->system;
}
if (is_delegation(delegation))
entry->delegated = TRUE;
}
static void copy_attrs(
OUT nfs41_file_info *dst,
IN const struct attr_cache_entry *src)
{
dst->change = src->change;
dst->size = src->size;
dst->time_access.seconds = src->time_access_s;
dst->time_access.nseconds = src->time_access_ns;
dst->time_create.seconds = src->time_create_s;
dst->time_create.nseconds = src->time_create_ns;
dst->time_modify.seconds = src->time_modify_s;
dst->time_modify.nseconds = src->time_modify_ns;
dst->type = src->type;
dst->numlinks = src->numlinks;
dst->mode = src->mode;
dst->fileid = src->fileid;
dst->hidden = src->hidden;
dst->system = src->system;
dst->archive = src->archive;
dst->attrmask.count = 2;
dst->attrmask.arr[0] = FATTR4_WORD0_TYPE | FATTR4_WORD0_CHANGE
| FATTR4_WORD0_SIZE | FATTR4_WORD0_FILEID
| FATTR4_WORD0_HIDDEN | FATTR4_WORD0_ARCHIVE;
dst->attrmask.arr[1] = FATTR4_WORD1_MODE
| FATTR4_WORD1_NUMLINKS | FATTR4_WORD1_TIME_ACCESS
| FATTR4_WORD1_TIME_CREATE | FATTR4_WORD1_TIME_MODIFY
| FATTR4_WORD1_SYSTEM;
}
/* name cache */
RB_HEAD(name_tree, name_cache_entry);
struct name_cache_entry {
char component[NFS41_MAX_COMPONENT_LEN];
nfs41_fh fh;
RB_ENTRY(name_cache_entry) rbnode;
struct name_tree rbchildren;
struct attr_cache_entry *attributes;
struct name_cache_entry *parent;
struct list_entry exp_entry;
time_t expiration;
unsigned short component_len;
};
#define NAME_ENTRY_SIZE sizeof(struct name_cache_entry)
int name_cmp(struct name_cache_entry *lhs, struct name_cache_entry *rhs)
{
const int diff = rhs->component_len - lhs->component_len;
return diff ? diff : strncmp(lhs->component, rhs->component, lhs->component_len);
}
RB_GENERATE(name_tree, name_cache_entry, rbnode, name_cmp)
struct nfs41_name_cache {
struct name_cache_entry *root;
struct name_cache_entry *pool;
struct attr_cache attributes;
struct list_entry exp_entries; /* list of entries by expiry */
uint32_t expiration;
uint32_t entries;
uint32_t max_entries;
uint32_t delegations;
uint32_t max_delegations;
SRWLOCK lock;
};
/* internal name cache functions used by the public name cache interface;
* these functions expect the caller to hold a lock on the cache */
#define name_entry(pos) list_container(pos, struct name_cache_entry, exp_entry)
static __inline bool_t name_cache_enabled(
IN struct nfs41_name_cache *cache)
{
return cache->expiration > 0;
}
static __inline void name_cache_entry_rename(
OUT struct name_cache_entry *entry,
IN const nfs41_component *component)
{
StringCchCopyNA(entry->component, NFS41_MAX_COMPONENT_LEN,
component->name, component->len);
entry->component_len = component->len;
}
static __inline void name_cache_remove(
IN struct name_cache_entry *entry,
IN struct name_cache_entry *parent)
{
RB_REMOVE(name_tree, &parent->rbchildren, entry);
entry->parent = NULL;
}
static void name_cache_unlink_children_recursive(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *parent);
static __inline void name_cache_unlink(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry)
{
/* remove the entry from the tree */
if (entry->parent)
name_cache_remove(entry, entry->parent);
else if (entry == cache->root)
cache->root = NULL;
/* unlink all of its children */
name_cache_unlink_children_recursive(cache, entry);
/* release the cached attributes */
if (entry->attributes) {
attr_cache_entry_deref(&cache->attributes, entry->attributes);
entry->attributes = NULL;
}
/* move it to the end of exp_entries for scavenging */
list_remove(&entry->exp_entry);
list_add_tail(&cache->exp_entries, &entry->exp_entry);
}
static void name_cache_unlink_children_recursive(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *parent)
{
struct name_cache_entry *entry, *tmp;
RB_FOREACH_SAFE(entry, name_tree, &parent->rbchildren, tmp)
name_cache_unlink(cache, entry);
}
static int name_cache_entry_create(
IN struct nfs41_name_cache *cache,
IN const nfs41_component *component,
OUT struct name_cache_entry **entry_out)
{
int status = NO_ERROR;
struct name_cache_entry *entry;
if (cache->entries >= cache->max_entries) {
/* scavenge the oldest entry */
if (list_empty(&cache->exp_entries)) {
status = ERROR_OUTOFMEMORY;
goto out;
}
entry = name_entry(cache->exp_entries.prev);
name_cache_unlink(cache, entry);
dprintf(NCLVL2, "name_cache_entry_create('%s') scavenged 0x%p\n",
component->name, entry);
} else {
/* take the next entry in the pool and add it to exp_entries */
entry = &cache->pool[cache->entries++];
list_init(&entry->exp_entry);
list_add_tail(&cache->exp_entries, &entry->exp_entry);
}
name_cache_entry_rename(entry, component);
*entry_out = entry;
out:
return status;
}
static void name_cache_entry_accessed(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry)
{
/* move the entry to the front of cache->exp_entries, then do
* the same for its parents, which are more costly to evict */
while (entry) {
/* if entry is delegated, it won't be in the list */
if (!list_empty(&entry->exp_entry)) {
list_remove(&entry->exp_entry);
list_add_head(&cache->exp_entries, &entry->exp_entry);
}
if (entry == entry->parent)
break;
entry = entry->parent;
}
}
static void name_cache_entry_updated(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry)
{
/* update the expiration timer */
entry->expiration = time(NULL) + cache->expiration;
name_cache_entry_accessed(cache, entry);
}
static int name_cache_entry_update(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry,
IN OPTIONAL const nfs41_fh *fh,
IN OPTIONAL const nfs41_file_info *info,
IN enum open_delegation_type4 delegation)
{
int status = NO_ERROR;
if (fh)
fh_copy(&entry->fh, fh);
else
entry->fh.len = 0;
if (info) {
if (entry->attributes == NULL) {
/* negative -> positive entry, create the attributes */
status = attr_cache_find_or_create(&cache->attributes,
info->fileid, &entry->attributes);
if (status)
goto out;
}
attr_cache_update(entry->attributes, info, delegation);
/* hold a reference as long as we have the delegation */
if (is_delegation(delegation)) {
attr_cache_entry_ref(&cache->attributes, entry->attributes);
cache->delegations++;
}
/* keep the entry from expiring */
if (entry->attributes->delegated)
list_remove(&entry->exp_entry);
} else if (entry->attributes) {
/* positive -> negative entry, deref the attributes */
attr_cache_entry_deref(&cache->attributes, entry->attributes);
entry->attributes = NULL;
}
name_cache_entry_updated(cache, entry);
out:
return status;
}
static int name_cache_entry_changed(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry,
IN const change_info4 *cinfo)
{
if (entry->attributes == NULL)
return FALSE;
if (cinfo->after == entry->attributes->change ||
(cinfo->atomic && cinfo->before == entry->attributes->change)) {
entry->attributes->change = cinfo->after;
name_cache_entry_updated(cache, entry);
dprintf(NCLVL1, "name_cache_entry_changed('%s') has not changed. "
"updated change=%llu\n", entry->component,
entry->attributes->change);
return FALSE;
} else {
dprintf(NCLVL1, "name_cache_entry_changed('%s') has changed: was %llu, "
"got before=%llu\n", entry->component,
entry->attributes->change, cinfo->before);
return TRUE;
}
}
static void name_cache_entry_invalidate(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *entry)
{
dprintf(NCLVL1, "name_cache_entry_invalidate('%s')\n", entry->component);
if (entry->attributes) {
/* flag attributes so that entry_invis() will return true
* if another entry attempts to use them */
entry->attributes->invalidated = 1;
}
name_cache_unlink(cache, entry);
}
static struct name_cache_entry* name_cache_search(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *parent,
IN const nfs41_component *component)
{
struct name_cache_entry tmp, *entry;
dprintf(NCLVL2, "--> name_cache_search('%.*s' under '%s')\n",
component->len, component->name, parent->component);
StringCchCopyNA(tmp.component, NFS41_MAX_COMPONENT_LEN,
component->name, component->len);
tmp.component_len = component->len;
entry = RB_FIND(name_tree, &parent->rbchildren, &tmp);
if (entry)
dprintf(NCLVL2, "<-- name_cache_search() "
"found existing entry 0x%p\n", entry);
else
dprintf(NCLVL2, "<-- name_cache_search() returning NULL\n");
return entry;
}
static int entry_invis(
IN struct name_cache_entry *entry,
OUT OPTIONAL bool_t *is_negative)
{
/* name entry timer expired? */
if (!list_empty(&entry->exp_entry) && time(NULL) > entry->expiration) {
dprintf(NCLVL2, "name_entry_expired('%s')\n", entry->component);
return 1;
}
/* negative lookup entry? */
if (entry->attributes == NULL) {
if (is_negative) *is_negative = 1;
dprintf(NCLVL2, "name_entry_negative('%s')\n", entry->component);
return 1;
}
/* attribute entry expired? */
if (attr_cache_entry_expired(entry->attributes)) {
dprintf(NCLVL2, "attr_entry_expired(%llu)\n",
entry->attributes->fileid);
return 1;
}
return 0;
}
static int name_cache_lookup(
IN struct nfs41_name_cache *cache,
IN bool_t skip_invis,
IN const char *path,
IN const char *path_end,
OUT OPTIONAL const char **remaining_path_out,
OUT OPTIONAL struct name_cache_entry **parent_out,
OUT OPTIONAL struct name_cache_entry **target_out,
OUT OPTIONAL bool_t *is_negative)
{
struct name_cache_entry *parent, *target;
nfs41_component component;
const char *path_pos;
int status = NO_ERROR;
dprintf(NCLVL1, "--> name_cache_lookup('%s')\n", path);
parent = NULL;
target = cache->root;
component.name = path_pos = path;
if (target == NULL || (skip_invis && entry_invis(target, is_negative))) {
target = NULL;
status = ERROR_PATH_NOT_FOUND;
goto out;
}
while (next_component(path_pos, path_end, &component)) {
parent = target;
target = name_cache_search(cache, parent, &component);
path_pos = component.name + component.len;
if (target == NULL || (skip_invis && entry_invis(target, is_negative))) {
target = NULL;
if (is_last_component(component.name, path_end))
status = ERROR_FILE_NOT_FOUND;
else
status = ERROR_PATH_NOT_FOUND;
break;
}
}
out:
if (remaining_path_out) *remaining_path_out = component.name;
if (parent_out) *parent_out = parent;
if (target_out) *target_out = target;
dprintf(NCLVL1, "<-- name_cache_lookup() returning %d\n", status);
return status;
}
static int name_cache_insert(
IN struct name_cache_entry *entry,
IN struct name_cache_entry *parent)
{
int status = NO_ERROR;
dprintf(NCLVL2, "--> name_cache_insert('%s')\n", entry->component);
if (RB_INSERT(name_tree, &parent->rbchildren, entry))
status = ERROR_FILE_EXISTS;
entry->parent = parent;
dprintf(NCLVL2, "<-- name_cache_insert() returning %u\n", status);
return status;
}
static int name_cache_find_or_create(
IN struct nfs41_name_cache *cache,
IN struct name_cache_entry *parent,
IN const nfs41_component *component,
OUT struct name_cache_entry **target_out)
{
int status = NO_ERROR;
dprintf(NCLVL1, "--> name_cache_find_or_create('%.*s' under '%s')\n",
component->len, component->name, parent->component);
*target_out = name_cache_search(cache, parent, component);
if (*target_out)
goto out;
status = name_cache_entry_create(cache, component, target_out);
if (status)
goto out;
status = name_cache_insert(*target_out, parent);
if (status)
goto out_err;
out:
dprintf(NCLVL1, "<-- name_cache_find_or_create() returning %d\n",
status);
return status;
out_err:
*target_out = NULL;
goto out;
}
/* public name cache interface, declared in name_cache.h */
/* assuming no hard links, calculate how many entries will fit in the cache */
#define SIZE_PER_ENTRY (ATTR_ENTRY_SIZE + NAME_ENTRY_SIZE)
#define NAME_CACHE_MAX_ENTRIES (NAME_CACHE_MAX_SIZE / SIZE_PER_ENTRY)
int nfs41_name_cache_create(
OUT struct nfs41_name_cache **cache_out)
{
struct nfs41_name_cache *cache;
int status = NO_ERROR;
dprintf(NCLVL1, "nfs41_name_cache_create()\n");
/* allocate the cache */
cache = calloc(1, sizeof(struct nfs41_name_cache));
if (cache == NULL) {
status = GetLastError();
goto out;
}
list_init(&cache->exp_entries);
cache->expiration = NAME_CACHE_EXPIRATION;
cache->max_entries = NAME_CACHE_MAX_ENTRIES;
cache->max_delegations = NAME_CACHE_MAX_ENTRIES / 2;
InitializeSRWLock(&cache->lock);
/* allocate a pool of entries */
cache->pool = calloc(cache->max_entries, NAME_ENTRY_SIZE);
if (cache->pool == NULL) {
status = GetLastError();
goto out_err_cache;
}
/* initialize the attribute cache */
status = attr_cache_init(&cache->attributes, cache->max_entries);
if (status)
goto out_err_pool;
*cache_out = cache;
out:
return status;
out_err_pool:
free(cache->pool);
out_err_cache:
free(cache);
goto out;
}
int nfs41_name_cache_free(
IN struct nfs41_name_cache **cache_out)
{
struct nfs41_name_cache *cache = *cache_out;
int status = NO_ERROR;
dprintf(NCLVL1, "nfs41_name_cache_free()\n");
/* free the attribute cache */
attr_cache_free(&cache->attributes);
/* free the name entry pool */
free(cache->pool);
free(cache);
*cache_out = NULL;
return status;
}
static __inline void copy_fh(
OUT nfs41_fh *dst,
IN OPTIONAL const struct name_cache_entry *src)
{
if (src)
fh_copy(dst, &src->fh);
else
dst->len = 0;
}
int nfs41_name_cache_lookup(
IN struct nfs41_name_cache *cache,
IN const char *path,
IN const char *path_end,
OUT OPTIONAL const char **remaining_path_out,
OUT OPTIONAL nfs41_fh *parent_out,
OUT OPTIONAL nfs41_fh *target_out,
OUT OPTIONAL nfs41_file_info *info_out,
OUT OPTIONAL bool_t *is_negative)
{
struct name_cache_entry *parent, *target;
const char *path_pos = path;
int status;
AcquireSRWLockShared(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
status = name_cache_lookup(cache, 1, path, path_end,
&path_pos, &parent, &target, is_negative);
if (parent_out) copy_fh(parent_out, parent);
if (target_out) copy_fh(target_out, target);
if (info_out && target && target->attributes)
copy_attrs(info_out, target->attributes);
out_unlock:
ReleaseSRWLockShared(&cache->lock);
if (remaining_path_out) *remaining_path_out = path_pos;
return status;
}
int nfs41_attr_cache_lookup(
IN struct nfs41_name_cache *cache,
IN uint64_t fileid,
OUT nfs41_file_info *info_out)
{
struct attr_cache_entry *entry;
int status = NO_ERROR;
dprintf(NCLVL1, "--> nfs41_attr_cache_lookup(%llu)\n", fileid);
AcquireSRWLockShared(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
entry = attr_cache_search(&cache->attributes, fileid);
if (entry == NULL || attr_cache_entry_expired(entry)) {
status = ERROR_FILE_NOT_FOUND;
goto out_unlock;
}
copy_attrs(info_out, entry);
out_unlock:
ReleaseSRWLockShared(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_attr_cache_lookup() returning %d\n", status);
return status;
}
int nfs41_attr_cache_update(
IN struct nfs41_name_cache *cache,
IN uint64_t fileid,
IN const nfs41_file_info *info)
{
struct attr_cache_entry *entry;
int status = NO_ERROR;
dprintf(NCLVL1, "--> nfs41_attr_cache_update(%llu)\n", fileid);
AcquireSRWLockExclusive(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
entry = attr_cache_search(&cache->attributes, fileid);
if (entry == NULL) {
status = ERROR_FILE_NOT_FOUND;
goto out_unlock;
}
attr_cache_update(entry, info, OPEN_DELEGATE_NONE);
out_unlock:
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_attr_cache_update() returning %d\n", status);
return status;
}
int nfs41_name_cache_insert(
IN struct nfs41_name_cache *cache,
IN const char *path,
IN const nfs41_component *name,
IN OPTIONAL const nfs41_fh *fh,
IN OPTIONAL const nfs41_file_info *info,
IN OPTIONAL const change_info4 *cinfo,
IN enum open_delegation_type4 delegation)
{
struct name_cache_entry *parent, *target;
int status;
dprintf(NCLVL1, "--> nfs41_name_cache_insert('%.*s')\n",
name->name + name->len - path, path);
AcquireSRWLockExclusive(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
/* limit the number of delegations to prevent attr cache starvation */
if (is_delegation(delegation) &&
cache->delegations >= cache->max_delegations) {
status = ERROR_TOO_MANY_OPEN_FILES;
goto out_unlock;
}
/* an empty path or component implies the root entry */
if (path == NULL || name == NULL || name->len == 0) {
/* create the root entry if it doesn't exist */
if (cache->root == NULL) {
const nfs41_component name = { "ROOT", 4 };
status = name_cache_entry_create(cache, &name, &cache->root);
if (status)
goto out_err_deleg;
}
target = cache->root;
} else {
/* find/create an entry under its parent */
status = name_cache_lookup(cache, 0, path,
name->name, NULL, NULL, &parent, NULL);
if (status)
goto out_err_deleg;
if (cinfo && name_cache_entry_changed(cache, parent, cinfo)) {
name_cache_entry_invalidate(cache, parent);
goto out_err_deleg;
}
status = name_cache_find_or_create(cache, parent, name, &target);
if (status)
goto out_err_deleg;
}
/* pass in the new fh/attributes */
status = name_cache_entry_update(cache, target, fh, info, delegation);
if (status)
goto out_err_update;
out_unlock:
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_name_cache_insert() returning %d\n",
status);
return status;
out_err_update:
/* a failure in name_cache_entry_update() leaves a negative entry
* where there shouldn't be one; remove it from the cache */
name_cache_entry_invalidate(cache, target);
out_err_deleg:
if (is_delegation(delegation)) {
/* we still need a reference to the attributes for the delegation */
struct attr_cache_entry *attributes;
status = attr_cache_find_or_create(&cache->attributes,
info->fileid, &attributes);
if (status == NO_ERROR) {
attr_cache_update(attributes, info, delegation);
cache->delegations++;
}
else
status = ERROR_TOO_MANY_OPEN_FILES;
}
goto out_unlock;
}
int nfs41_name_cache_delegreturn(
IN struct nfs41_name_cache *cache,
IN uint64_t fileid,
IN const char *path,
IN const nfs41_component *name)
{
struct name_cache_entry *parent, *target;
struct attr_cache_entry *attributes;
int status;
dprintf(NCLVL1, "--> nfs41_name_cache_delegreturn(%llu, '%s')\n",
fileid, path);
AcquireSRWLockExclusive(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
status = name_cache_lookup(cache, 0, path,
name->name + name->len, NULL, &parent, &target, NULL);
if (status == NO_ERROR) {
/* put the name cache entry back on the exp_entries list */
list_add_head(&cache->exp_entries, &target->exp_entry);
name_cache_entry_updated(cache, target);
attributes = target->attributes;
} else {
/* should still have an attr cache entry */
attributes = attr_cache_search(&cache->attributes, fileid);
}
if (attributes == NULL) {
status = ERROR_FILE_NOT_FOUND;
goto out_unlock;
}
/* release the reference from name_cache_entry_update() */
if (attributes->delegated) {
attributes->delegated = FALSE;
attr_cache_entry_deref(&cache->attributes, attributes);
assert(cache->delegations > 0);
cache->delegations--;
}
status = NO_ERROR;
out_unlock:
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_name_cache_delegreturn() returning %d\n", status);
return status;
}
int nfs41_name_cache_remove(
IN struct nfs41_name_cache *cache,
IN const char *path,
IN const nfs41_component *name,
IN uint64_t fileid,
IN const change_info4 *cinfo)
{
struct name_cache_entry *parent, *target;
struct attr_cache_entry *attributes = NULL;
int status;
dprintf(NCLVL1, "--> nfs41_name_cache_remove('%s')\n", path);
AcquireSRWLockExclusive(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
status = name_cache_lookup(cache, 0, path,
name->name + name->len, NULL, &parent, &target, NULL);
if (status == ERROR_PATH_NOT_FOUND)
goto out_attributes;
if (cinfo && name_cache_entry_changed(cache, parent, cinfo)) {
name_cache_entry_invalidate(cache, parent);
goto out_attributes;
}
if (status == ERROR_FILE_NOT_FOUND)
goto out_attributes;
if (target->attributes)
target->attributes->numlinks--;
/* make this a negative entry and unlink children */
name_cache_entry_update(cache, target, NULL, NULL, OPEN_DELEGATE_NONE);
name_cache_unlink_children_recursive(cache, target);
out_unlock:
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_name_cache_remove() returning %d\n", status);
return status;
out_attributes:
/* in the presence of other links, we need to update numlinks
* regardless of a failure to find the target entry */
dprintf(NCLVL1, "nfs41_name_cache_remove: need to find attributes for %s\n", path);
attributes = attr_cache_search(&cache->attributes, fileid);
if (attributes)
attributes->numlinks--;
goto out_unlock;
}
int nfs41_name_cache_rename(
IN struct nfs41_name_cache *cache,
IN const char *src_path,
IN const nfs41_component *src_name,
IN const change_info4 *src_cinfo,
IN const char *dst_path,
IN const nfs41_component *dst_name,
IN const change_info4 *dst_cinfo)
{
struct name_cache_entry *src_parent, *src;
struct name_cache_entry *dst_parent;
int status = NO_ERROR;
dprintf(NCLVL1, "--> nfs41_name_cache_rename('%s' to '%s')\n",
src_path, dst_path);
AcquireSRWLockExclusive(&cache->lock);
if (!name_cache_enabled(cache)) {
status = ERROR_NOT_SUPPORTED;
goto out_unlock;
}
/* look up dst_parent */
status = name_cache_lookup(cache, 0, dst_path,
dst_name->name, NULL, NULL, &dst_parent, NULL);
/* we can't create the dst entry without a parent */
if (status || dst_parent->attributes == NULL) {
/* if src exists, make it negative */
dprintf(NCLVL1, "nfs41_name_cache_rename: adding negative cache "
"entry for %.*s\n", src_name->len, src_name->name);
status = name_cache_lookup(cache, 0, src_path,
src_name->name + src_name->len, NULL, NULL, &src, NULL);
if (status == NO_ERROR) {
name_cache_entry_update(cache, src, NULL, NULL, OPEN_DELEGATE_NONE);
name_cache_unlink_children_recursive(cache, src);
}
status = ERROR_PATH_NOT_FOUND;
goto out_unlock;
}
/* look up src_parent and src */
status = name_cache_lookup(cache, 0, src_path,
src_name->name + src_name->len, NULL, &src_parent, &src, NULL);
/* we can't create the dst entry without valid attributes */
if (status || src->attributes == NULL) {
/* remove dst if it exists */
struct name_cache_entry *dst;
dprintf(NCLVL1, "nfs41_name_cache_rename: removing negative cache "
"entry for %.*s\n", dst_name->len, dst_name->name);
dst = name_cache_search(cache, dst_parent, dst_name);
if (dst) name_cache_unlink(cache, dst);
goto out_unlock;
}
if (name_cache_entry_changed(cache, dst_parent, dst_cinfo)) {
name_cache_entry_invalidate(cache, dst_parent);
/* if dst_parent and src_parent are both gone,
* we no longer have an entry to rename */
if (dst_parent == src_parent)
goto out_unlock;
} else {
struct name_cache_entry *existing;
existing = name_cache_search(cache, dst_parent, dst_name);
if (existing) {
if (existing == src)
goto out_unlock;
/* remove the existing entry, but don't unlink it yet;
* we may reuse it for a negative entry */
name_cache_remove(existing, dst_parent);
}
/* move the src entry under dst_parent */
name_cache_remove(src, src_parent);
name_cache_entry_rename(src, dst_name);
name_cache_insert(src, dst_parent);
if (existing) {
/* recycle 'existing' as the negative entry 'src' */
name_cache_entry_rename(existing, src_name);
name_cache_insert(existing, src_parent);
}
src = existing;
}
if (name_cache_entry_changed(cache, src_parent, src_cinfo)) {
name_cache_entry_invalidate(cache, src_parent);
goto out_unlock;
}
/* leave a negative entry where the file used to be */
if (src == NULL) {
/* src was moved, create a new entry in its place */
status = name_cache_find_or_create(cache, src_parent, src_name, &src);
if (status)
goto out_unlock;
}
name_cache_entry_update(cache, src, NULL, NULL, OPEN_DELEGATE_NONE);
name_cache_unlink_children_recursive(cache, src);
out_unlock:
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- nfs41_name_cache_rename() returning %d\n", status);
return status;
}
/* nfs41_name_cache_resolve_fh() */
#define MAX_PUTFH_PER_COMPOUND 16
static bool_t get_path_fhs(
IN struct nfs41_name_cache *cache,
IN nfs41_abs_path *path,
IN OUT const char **path_pos,
IN uint32_t max_components,
OUT nfs41_path_fh *files,
OUT uint32_t *count)
{
struct name_cache_entry *target;
const char *path_end = path->path + path->len;
nfs41_component *name;
uint32_t i;
int status;
*count = 0;
AcquireSRWLockShared(&cache->lock);
/* look up the parent of the first component */
status = name_cache_lookup(cache, 1, path->path,
*path_pos, NULL, NULL, &target, NULL);
if (status)
goto out_unlock;
for (i = 0; i < max_components; i++) {
files[i].path = path;
name = &files[i].name;
if (!next_component(*path_pos, path_end, name))
break;
*path_pos = name->name + name->len;
target = name_cache_search(cache, target, name);
if (target == NULL || entry_invis(target, NULL)) {
if (is_last_component(name->name, path_end))
status = ERROR_FILE_NOT_FOUND;
else
status = ERROR_PATH_NOT_FOUND;
goto out_unlock;
}
/* make copies for use outside of cache->lock */
fh_copy(&files[i].fh, &target->fh);
(*count)++;
}
out_unlock:
ReleaseSRWLockShared(&cache->lock);
return *count && status == 0;
}
static int rpc_array_putfh(
IN nfs41_session *session,
IN nfs41_path_fh *files,
IN uint32_t count,
OUT uint32_t *valid_out)
{
nfs41_compound compound;
nfs_argop4 argops[1+MAX_PUTFH_PER_COMPOUND];
nfs_resop4 resops[1+MAX_PUTFH_PER_COMPOUND];
nfs41_sequence_args sequence_args;
nfs41_sequence_res sequence_res = { 0 };
nfs41_putfh_args putfh_args[MAX_PUTFH_PER_COMPOUND];
nfs41_putfh_res putfh_res[MAX_PUTFH_PER_COMPOUND] = { 0 };
uint32_t i;
int status;
*valid_out = 0;
compound_init(&compound, argops, resops, "array_putfh");
compound_add_op(&compound, OP_SEQUENCE, &sequence_args, &sequence_res);
nfs41_session_sequence(&sequence_args, session, 0);
for (i = 0; i < count; i++){
compound_add_op(&compound, OP_PUTFH, &putfh_args[i], &putfh_res[i]);
putfh_args[i].file = &files[i];
putfh_args[i].in_recovery = 1;
}
status = compound_encode_send_decode(session, &compound, TRUE);
if (status) goto out;
status = sequence_res.sr_status;
if (status) goto out;
for (i = 0; i < count; i++) {
status = putfh_res[i].status;
if (status) break;
}
*valid_out = i;
out:
return status;
}
static int delete_stale_component(
IN struct nfs41_name_cache *cache,
IN nfs41_session *session,
IN const nfs41_abs_path *path,
IN const nfs41_component *component)
{
struct name_cache_entry *target;
int status;
dprintf(NCLVL1, "--> delete_stale_component('%s')\n",
component->name);
AcquireSRWLockExclusive(&cache->lock);
status = name_cache_lookup(cache, 0, path->path,
component->name + component->len, NULL, NULL, &target, NULL);
if (status == NO_ERROR)
name_cache_unlink(cache, target);
ReleaseSRWLockExclusive(&cache->lock);
dprintf(NCLVL1, "<-- delete_stale_component() returning %d\n", status);
return status;
}
static __inline uint32_t max_putfh_components(
IN const nfs41_session *session)
{
const uint32_t comps = session->fore_chan_attrs.ca_maxoperations - 1;
return min(comps, MAX_PUTFH_PER_COMPOUND);
}
int nfs41_name_cache_remove_stale(
IN struct nfs41_name_cache *cache,
IN nfs41_session *session,
IN nfs41_abs_path *path)
{
nfs41_path_fh files[MAX_PUTFH_PER_COMPOUND];
const char *path_pos = path->path;
const char* const path_end = path->path + path->len;
const uint32_t max_components = max_putfh_components(session);
uint32_t count, index;
int status = NO_ERROR;
AcquireSRWLockShared(&cache->lock);
/* if there's no cache, don't check any components */
if (!name_cache_enabled(cache))
path_pos = path_end;
ReleaseSRWLockShared(&cache->lock);
/* hold a lock on the path to protect against rename */
AcquireSRWLockShared(&path->lock);
while (get_path_fhs(cache, path, &path_pos, max_components, files, &count)) {
status = rpc_array_putfh(session, files, count, &index);
if (status == NFS4ERR_STALE || status == NFS4ERR_FHEXPIRED) {
status = delete_stale_component(cache,
session, path, &files[index].name);
break;
}
if (status) {
status = nfs_to_windows_error(status, ERROR_FILE_NOT_FOUND);
break;
}
}
ReleaseSRWLockShared(&path->lock);
return status;
}
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