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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c')
-rw-r--r--ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c286
1 files changed, 0 insertions, 286 deletions
diff --git a/ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c b/ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c
deleted file mode 100644
index 08d9a207..00000000
--- a/ANDROID_3.4.5/drivers/md/dm-log-userspace-transfer.c
+++ /dev/null
@@ -1,286 +0,0 @@
-/*
- * Copyright (C) 2006-2009 Red Hat, Inc.
- *
- * This file is released under the LGPL.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <net/sock.h>
-#include <linux/workqueue.h>
-#include <linux/connector.h>
-#include <linux/device-mapper.h>
-#include <linux/dm-log-userspace.h>
-
-#include "dm-log-userspace-transfer.h"
-
-static uint32_t dm_ulog_seq;
-
-/*
- * Netlink/Connector is an unreliable protocol. How long should
- * we wait for a response before assuming it was lost and retrying?
- * (If we do receive a response after this time, it will be discarded
- * and the response to the resent request will be waited for.
- */
-#define DM_ULOG_RETRY_TIMEOUT (15 * HZ)
-
-/*
- * Pre-allocated space for speed
- */
-#define DM_ULOG_PREALLOCED_SIZE 512
-static struct cn_msg *prealloced_cn_msg;
-static struct dm_ulog_request *prealloced_ulog_tfr;
-
-static struct cb_id ulog_cn_id = {
- .idx = CN_IDX_DM,
- .val = CN_VAL_DM_USERSPACE_LOG
-};
-
-static DEFINE_MUTEX(dm_ulog_lock);
-
-struct receiving_pkg {
- struct list_head list;
- struct completion complete;
-
- uint32_t seq;
-
- int error;
- size_t *data_size;
- char *data;
-};
-
-static DEFINE_SPINLOCK(receiving_list_lock);
-static struct list_head receiving_list;
-
-static int dm_ulog_sendto_server(struct dm_ulog_request *tfr)
-{
- int r;
- struct cn_msg *msg = prealloced_cn_msg;
-
- memset(msg, 0, sizeof(struct cn_msg));
-
- msg->id.idx = ulog_cn_id.idx;
- msg->id.val = ulog_cn_id.val;
- msg->ack = 0;
- msg->seq = tfr->seq;
- msg->len = sizeof(struct dm_ulog_request) + tfr->data_size;
-
- r = cn_netlink_send(msg, 0, gfp_any());
-
- return r;
-}
-
-/*
- * Parameters for this function can be either msg or tfr, but not
- * both. This function fills in the reply for a waiting request.
- * If just msg is given, then the reply is simply an ACK from userspace
- * that the request was received.
- *
- * Returns: 0 on success, -ENOENT on failure
- */
-static int fill_pkg(struct cn_msg *msg, struct dm_ulog_request *tfr)
-{
- uint32_t rtn_seq = (msg) ? msg->seq : (tfr) ? tfr->seq : 0;
- struct receiving_pkg *pkg;
-
- /*
- * The 'receiving_pkg' entries in this list are statically
- * allocated on the stack in 'dm_consult_userspace'.
- * Each process that is waiting for a reply from the user
- * space server will have an entry in this list.
- *
- * We are safe to do it this way because the stack space
- * is unique to each process, but still addressable by
- * other processes.
- */
- list_for_each_entry(pkg, &receiving_list, list) {
- if (rtn_seq != pkg->seq)
- continue;
-
- if (msg) {
- pkg->error = -msg->ack;
- /*
- * If we are trying again, we will need to know our
- * storage capacity. Otherwise, along with the
- * error code, we make explicit that we have no data.
- */
- if (pkg->error != -EAGAIN)
- *(pkg->data_size) = 0;
- } else if (tfr->data_size > *(pkg->data_size)) {
- DMERR("Insufficient space to receive package [%u] "
- "(%u vs %zu)", tfr->request_type,
- tfr->data_size, *(pkg->data_size));
-
- *(pkg->data_size) = 0;
- pkg->error = -ENOSPC;
- } else {
- pkg->error = tfr->error;
- memcpy(pkg->data, tfr->data, tfr->data_size);
- *(pkg->data_size) = tfr->data_size;
- }
- complete(&pkg->complete);
- return 0;
- }
-
- return -ENOENT;
-}
-
-/*
- * This is the connector callback that delivers data
- * that was sent from userspace.
- */
-static void cn_ulog_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
-{
- struct dm_ulog_request *tfr = (struct dm_ulog_request *)(msg + 1);
-
- if (!capable(CAP_SYS_ADMIN))
- return;
-
- spin_lock(&receiving_list_lock);
- if (msg->len == 0)
- fill_pkg(msg, NULL);
- else if (msg->len < sizeof(*tfr))
- DMERR("Incomplete message received (expected %u, got %u): [%u]",
- (unsigned)sizeof(*tfr), msg->len, msg->seq);
- else
- fill_pkg(NULL, tfr);
- spin_unlock(&receiving_list_lock);
-}
-
-/**
- * dm_consult_userspace
- * @uuid: log's universal unique identifier (must be DM_UUID_LEN in size)
- * @luid: log's local unique identifier
- * @request_type: found in include/linux/dm-log-userspace.h
- * @data: data to tx to the server
- * @data_size: size of data in bytes
- * @rdata: place to put return data from server
- * @rdata_size: value-result (amount of space given/amount of space used)
- *
- * rdata_size is undefined on failure.
- *
- * Memory used to communicate with userspace is zero'ed
- * before populating to ensure that no unwanted bits leak
- * from kernel space to user-space. All userspace log communications
- * between kernel and user space go through this function.
- *
- * Returns: 0 on success, -EXXX on failure
- **/
-int dm_consult_userspace(const char *uuid, uint64_t luid, int request_type,
- char *data, size_t data_size,
- char *rdata, size_t *rdata_size)
-{
- int r = 0;
- size_t dummy = 0;
- int overhead_size = sizeof(struct dm_ulog_request) + sizeof(struct cn_msg);
- struct dm_ulog_request *tfr = prealloced_ulog_tfr;
- struct receiving_pkg pkg;
-
- /*
- * Given the space needed to hold the 'struct cn_msg' and
- * 'struct dm_ulog_request' - do we have enough payload
- * space remaining?
- */
- if (data_size > (DM_ULOG_PREALLOCED_SIZE - overhead_size)) {
- DMINFO("Size of tfr exceeds preallocated size");
- return -EINVAL;
- }
-
- if (!rdata_size)
- rdata_size = &dummy;
-resend:
- /*
- * We serialize the sending of requests so we can
- * use the preallocated space.
- */
- mutex_lock(&dm_ulog_lock);
-
- memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - sizeof(struct cn_msg));
- memcpy(tfr->uuid, uuid, DM_UUID_LEN);
- tfr->version = DM_ULOG_REQUEST_VERSION;
- tfr->luid = luid;
- tfr->seq = dm_ulog_seq++;
-
- /*
- * Must be valid request type (all other bits set to
- * zero). This reserves other bits for possible future
- * use.
- */
- tfr->request_type = request_type & DM_ULOG_REQUEST_MASK;
-
- tfr->data_size = data_size;
- if (data && data_size)
- memcpy(tfr->data, data, data_size);
-
- memset(&pkg, 0, sizeof(pkg));
- init_completion(&pkg.complete);
- pkg.seq = tfr->seq;
- pkg.data_size = rdata_size;
- pkg.data = rdata;
- spin_lock(&receiving_list_lock);
- list_add(&(pkg.list), &receiving_list);
- spin_unlock(&receiving_list_lock);
-
- r = dm_ulog_sendto_server(tfr);
-
- mutex_unlock(&dm_ulog_lock);
-
- if (r) {
- DMERR("Unable to send log request [%u] to userspace: %d",
- request_type, r);
- spin_lock(&receiving_list_lock);
- list_del_init(&(pkg.list));
- spin_unlock(&receiving_list_lock);
-
- goto out;
- }
-
- r = wait_for_completion_timeout(&(pkg.complete), DM_ULOG_RETRY_TIMEOUT);
- spin_lock(&receiving_list_lock);
- list_del_init(&(pkg.list));
- spin_unlock(&receiving_list_lock);
- if (!r) {
- DMWARN("[%s] Request timed out: [%u/%u] - retrying",
- (strlen(uuid) > 8) ?
- (uuid + (strlen(uuid) - 8)) : (uuid),
- request_type, pkg.seq);
- goto resend;
- }
-
- r = pkg.error;
- if (r == -EAGAIN)
- goto resend;
-
-out:
- return r;
-}
-
-int dm_ulog_tfr_init(void)
-{
- int r;
- void *prealloced;
-
- INIT_LIST_HEAD(&receiving_list);
-
- prealloced = kmalloc(DM_ULOG_PREALLOCED_SIZE, GFP_KERNEL);
- if (!prealloced)
- return -ENOMEM;
-
- prealloced_cn_msg = prealloced;
- prealloced_ulog_tfr = prealloced + sizeof(struct cn_msg);
-
- r = cn_add_callback(&ulog_cn_id, "dmlogusr", cn_ulog_callback);
- if (r) {
- cn_del_callback(&ulog_cn_id);
- return r;
- }
-
- return 0;
-}
-
-void dm_ulog_tfr_exit(void)
-{
- cn_del_callback(&ulog_cn_id);
- kfree(prealloced_cn_msg);
-}