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linux-next/drivers/s390/scsi/zfcp_qdio.c
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license 
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

506 lines
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// SPDX-License-Identifier: GPL-2.0
/*
* zfcp device driver
*
* Setup and helper functions to access QDIO.
*
* Copyright IBM Corp. 2002, 2010
*/
#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/slab.h>
#include <linux/module.h>
#include "zfcp_ext.h"
#include "zfcp_qdio.h"
static bool enable_multibuffer = true;
module_param_named(datarouter, enable_multibuffer, bool, 0400);
MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");
static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id,
unsigned int qdio_err)
{
struct zfcp_adapter *adapter = qdio->adapter;
dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
if (qdio_err & QDIO_ERROR_SLSB_STATE) {
zfcp_qdio_siosl(adapter);
zfcp_erp_adapter_shutdown(adapter, 0, id);
return;
}
zfcp_erp_adapter_reopen(adapter,
ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
ZFCP_STATUS_COMMON_ERP_FAILED, id);
}
static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
{
int i, sbal_idx;
for (i = first; i < first + cnt; i++) {
sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
}
}
/* this needs to be called prior to updating the queue fill level */
static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
{
unsigned long long now, span;
int used;
now = get_tod_clock_monotonic();
span = (now - qdio->req_q_time) >> 12;
used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free);
qdio->req_q_util += used * span;
qdio->req_q_time = now;
}
static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
int queue_no, int idx, int count,
unsigned long parm)
{
struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
if (unlikely(qdio_err)) {
zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
return;
}
/* cleanup all SBALs being program-owned now */
zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
spin_lock_irq(&qdio->stat_lock);
zfcp_qdio_account(qdio);
spin_unlock_irq(&qdio->stat_lock);
atomic_add(count, &qdio->req_q_free);
wake_up(&qdio->req_q_wq);
}
static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
int queue_no, int idx, int count,
unsigned long parm)
{
struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
struct zfcp_adapter *adapter = qdio->adapter;
int sbal_no, sbal_idx;
if (unlikely(qdio_err)) {
if (zfcp_adapter_multi_buffer_active(adapter)) {
void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
struct qdio_buffer_element *sbale;
u64 req_id;
u8 scount;
memset(pl, 0,
ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
sbale = qdio->res_q[idx]->element;
req_id = (u64) sbale->addr;
scount = min(sbale->scount + 1,
ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);
/* incl. signaling SBAL */
for (sbal_no = 0; sbal_no < scount; sbal_no++) {
sbal_idx = (idx + sbal_no) %
QDIO_MAX_BUFFERS_PER_Q;
pl[sbal_no] = qdio->res_q[sbal_idx];
}
zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
}
zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
return;
}
/*
* go through all SBALs from input queue currently
* returned by QDIO layer
*/
for (sbal_no = 0; sbal_no < count; sbal_no++) {
sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
/* go through all SBALEs of SBAL */
zfcp_fsf_reqid_check(qdio, sbal_idx);
}
/*
* put SBALs back to response queue
*/
if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count))
zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
}
static struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
struct qdio_buffer_element *sbale;
/* set last entry flag in current SBALE of current SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
/* don't exceed last allowed SBAL */
if (q_req->sbal_last == q_req->sbal_limit)
return NULL;
/* set chaining flag in first SBALE of current SBAL */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;
/* calculate index of next SBAL */
q_req->sbal_last++;
q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
/* keep this requests number of SBALs up-to-date */
q_req->sbal_number++;
BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
/* start at first SBALE of new SBAL */
q_req->sbale_curr = 0;
/* set storage-block type for new SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->sflags |= q_req->sbtype;
return sbale;
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
return zfcp_qdio_sbal_chain(qdio, q_req);
q_req->sbale_curr++;
return zfcp_qdio_sbale_curr(qdio, q_req);
}
/**
* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_qdio_req
* @sg: scatter-gather list
* @max_sbals: upper bound for number of SBALs to be used
* Returns: zero or -EINVAL on error
*/
int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
struct scatterlist *sg)
{
struct qdio_buffer_element *sbale;
/* set storage-block type for this request */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->sflags |= q_req->sbtype;
for (; sg; sg = sg_next(sg)) {
sbale = zfcp_qdio_sbale_next(qdio, q_req);
if (!sbale) {
atomic_inc(&qdio->req_q_full);
zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
q_req->sbal_number);
return -EINVAL;
}
sbale->addr = sg_virt(sg);
sbale->length = sg->length;
}
return 0;
}
static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
{
if (atomic_read(&qdio->req_q_free) ||
!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return 1;
return 0;
}
/**
* zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
* @qdio: pointer to struct zfcp_qdio
*
* The req_q_lock must be held by the caller of this function, and
* this function may only be called from process context; it will
* sleep when waiting for a free sbal.
*
* Returns: 0 on success, -EIO if there is no free sbal after waiting.
*/
int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
{
long ret;
ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,
zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);
if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return -EIO;
if (ret > 0)
return 0;
if (!ret) {
atomic_inc(&qdio->req_q_full);
/* assume hanging outbound queue, try queue recovery */
zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
}
return -EIO;
}
/**
* zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_qdio_req
* Returns: 0 on success, error otherwise
*/
int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
int retval;
u8 sbal_number = q_req->sbal_number;
spin_lock(&qdio->stat_lock);
zfcp_qdio_account(qdio);
spin_unlock(&qdio->stat_lock);
retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0,
q_req->sbal_first, sbal_number);
if (unlikely(retval)) {
zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
sbal_number);
return retval;
}
/* account for transferred buffers */
atomic_sub(sbal_number, &qdio->req_q_free);
qdio->req_q_idx += sbal_number;
qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
return 0;
}
static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
struct zfcp_qdio *qdio)
{
memset(id, 0, sizeof(*id));
id->cdev = qdio->adapter->ccw_device;
id->q_format = QDIO_ZFCP_QFMT;
memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
ASCEBC(id->adapter_name, 8);
id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
if (enable_multibuffer)
id->qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;
id->no_input_qs = 1;
id->no_output_qs = 1;
id->input_handler = zfcp_qdio_int_resp;
id->output_handler = zfcp_qdio_int_req;
id->int_parm = (unsigned long) qdio;
id->input_sbal_addr_array = (void **) (qdio->res_q);
id->output_sbal_addr_array = (void **) (qdio->req_q);
id->scan_threshold =
QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2;
}
/**
* zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
* @adapter: pointer to struct zfcp_adapter
* Returns: -ENOMEM on memory allocation error or return value from
* qdio_allocate
*/
static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
{
struct qdio_initialize init_data;
int ret;
ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
if (ret)
return -ENOMEM;
ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
if (ret)
goto free_req_q;
zfcp_qdio_setup_init_data(&init_data, qdio);
init_waitqueue_head(&qdio->req_q_wq);
ret = qdio_allocate(&init_data);
if (ret)
goto free_res_q;
return 0;
free_res_q:
qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
free_req_q:
qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
return ret;
}
/**
* zfcp_close_qdio - close qdio queues for an adapter
* @qdio: pointer to structure zfcp_qdio
*/
void zfcp_qdio_close(struct zfcp_qdio *qdio)
{
struct zfcp_adapter *adapter = qdio->adapter;
int idx, count;
if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return;
/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
spin_lock_irq(&qdio->req_q_lock);
atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
spin_unlock_irq(&qdio->req_q_lock);
wake_up(&qdio->req_q_wq);
qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
/* cleanup used outbound sbals */
count = atomic_read(&qdio->req_q_free);
if (count < QDIO_MAX_BUFFERS_PER_Q) {
idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;
count = QDIO_MAX_BUFFERS_PER_Q - count;
zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
}
qdio->req_q_idx = 0;
atomic_set(&qdio->req_q_free, 0);
}
/**
* zfcp_qdio_open - prepare and initialize response queue
* @qdio: pointer to struct zfcp_qdio
* Returns: 0 on success, otherwise -EIO
*/
int zfcp_qdio_open(struct zfcp_qdio *qdio)
{
struct qdio_buffer_element *sbale;
struct qdio_initialize init_data;
struct zfcp_adapter *adapter = qdio->adapter;
struct ccw_device *cdev = adapter->ccw_device;
struct qdio_ssqd_desc ssqd;
int cc;
if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
return -EIO;
atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
&qdio->adapter->status);
zfcp_qdio_setup_init_data(&init_data, qdio);
if (qdio_establish(&init_data))
goto failed_establish;
if (qdio_get_ssqd_desc(init_data.cdev, &ssqd))
goto failed_qdio;
if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
&qdio->adapter->status);
if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {
atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;
} else {
atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;
}
qdio->max_sbale_per_req =
ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal
- 2;
if (qdio_activate(cdev))
goto failed_qdio;
for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
sbale = &(qdio->res_q[cc]->element[0]);
sbale->length = 0;
sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;
sbale->sflags = 0;
sbale->addr = NULL;
}
if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q))
goto failed_qdio;
/* set index of first available SBALS / number of available SBALS */
qdio->req_q_idx = 0;
atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
if (adapter->scsi_host) {
adapter->scsi_host->sg_tablesize = qdio->max_sbale_per_req;
adapter->scsi_host->max_sectors = qdio->max_sbale_per_req * 8;
}
return 0;
failed_qdio:
qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
failed_establish:
dev_err(&cdev->dev,
"Setting up the QDIO connection to the FCP adapter failed\n");
return -EIO;
}
void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
{
if (!qdio)
return;
if (qdio->adapter->ccw_device)
qdio_free(qdio->adapter->ccw_device);
qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
kfree(qdio);
}
int zfcp_qdio_setup(struct zfcp_adapter *adapter)
{
struct zfcp_qdio *qdio;
qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
if (!qdio)
return -ENOMEM;
qdio->adapter = adapter;
if (zfcp_qdio_allocate(qdio)) {
kfree(qdio);
return -ENOMEM;
}
spin_lock_init(&qdio->req_q_lock);
spin_lock_init(&qdio->stat_lock);
adapter->qdio = qdio;
return 0;
}
/**
* zfcp_qdio_siosl - Trigger logging in FCP channel
* @adapter: The zfcp_adapter where to trigger logging
*
* Call the cio siosl function to trigger hardware logging. This
* wrapper function sets a flag to ensure hardware logging is only
* triggered once before going through qdio shutdown.
*
* The triggers are always run from qdio tasklet context, so no
* additional synchronization is necessary.
*/
void zfcp_qdio_siosl(struct zfcp_adapter *adapter)
{
int rc;
if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)
return;
rc = ccw_device_siosl(adapter->ccw_device);
if (!rc)
atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
&adapter->status);
}
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