- 根目录:
- drivers
- crypto
- nx
- nx-842.c
/*
* Driver for IBM Power 842 compression accelerator
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright (C) IBM Corporation, 2012
*
* Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
* Seth Jennings <sjenning@linux.vnet.ibm.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/nx842.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <asm/page.h>
#include <asm/vio.h>
#include "nx_csbcpb.h" /* struct nx_csbcpb */
#define MODULE_NAME "nx-compress"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Robert Jennings <rcj@linux.vnet.ibm.com>");
MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
#define SHIFT_4K 12
#define SHIFT_64K 16
#define SIZE_4K (1UL << SHIFT_4K)
#define SIZE_64K (1UL << SHIFT_64K)
/* IO buffer must be 128 byte aligned */
#define IO_BUFFER_ALIGN 128
struct nx842_header {
int blocks_nr; /* number of compressed blocks */
int offset; /* offset of the first block (from beginning of header) */
int sizes[0]; /* size of compressed blocks */
};
static inline int nx842_header_size(const struct nx842_header *hdr)
{
return sizeof(struct nx842_header) +
hdr->blocks_nr * sizeof(hdr->sizes[0]);
}
/* Macros for fields within nx_csbcpb */
/* Check the valid bit within the csbcpb valid field */
#define NX842_CSBCBP_VALID_CHK(x) (x & BIT_MASK(7))
/* CE macros operate on the completion_extension field bits in the csbcpb.
* CE0 0=full completion, 1=partial completion
* CE1 0=CE0 indicates completion, 1=termination (output may be modified)
* CE2 0=processed_bytes is source bytes, 1=processed_bytes is target bytes */
#define NX842_CSBCPB_CE0(x) (x & BIT_MASK(7))
#define NX842_CSBCPB_CE1(x) (x & BIT_MASK(6))
#define NX842_CSBCPB_CE2(x) (x & BIT_MASK(5))
/* The NX unit accepts data only on 4K page boundaries */
#define NX842_HW_PAGE_SHIFT SHIFT_4K
#define NX842_HW_PAGE_SIZE (ASM_CONST(1) << NX842_HW_PAGE_SHIFT)
#define NX842_HW_PAGE_MASK (~(NX842_HW_PAGE_SIZE-1))
enum nx842_status {
UNAVAILABLE,
AVAILABLE
};
struct ibm_nx842_counters {
atomic64_t comp_complete;
atomic64_t comp_failed;
atomic64_t decomp_complete;
atomic64_t decomp_failed;
atomic64_t swdecomp;
atomic64_t comp_times[32];
atomic64_t decomp_times[32];
};
static struct nx842_devdata {
struct vio_dev *vdev;
struct device *dev;
struct ibm_nx842_counters *counters;
unsigned int max_sg_len;
unsigned int max_sync_size;
unsigned int max_sync_sg;
enum nx842_status status;
} __rcu *devdata;
static DEFINE_SPINLOCK(devdata_mutex);
#define NX842_COUNTER_INC(_x) \
static inline void nx842_inc_##_x( \
const struct nx842_devdata *dev) { \
if (dev) \
atomic64_inc(&dev->counters->_x); \
}
NX842_COUNTER_INC(comp_complete);
NX842_COUNTER_INC(comp_failed);
NX842_COUNTER_INC(decomp_complete);
NX842_COUNTER_INC(decomp_failed);
NX842_COUNTER_INC(swdecomp);
#define NX842_HIST_SLOTS 16
static void ibm_nx842_incr_hist(atomic64_t *times, unsigned int time)
{
int bucket = fls(time);
if (bucket)
bucket = min((NX842_HIST_SLOTS - 1), bucket - 1);
atomic64_inc(×[bucket]);
}
/* NX unit operation flags */
#define NX842_OP_COMPRESS 0x0
#define NX842_OP_CRC 0x1
#define NX842_OP_DECOMPRESS 0x2
#define NX842_OP_COMPRESS_CRC (NX842_OP_COMPRESS | NX842_OP_CRC)
#define NX842_OP_DECOMPRESS_CRC (NX842_OP_DECOMPRESS | NX842_OP_CRC)
#define NX842_OP_ASYNC (1<<23)
#define NX842_OP_NOTIFY (1<<22)
#define NX842_OP_NOTIFY_INT(x) ((x & 0xff)<<8)
static unsigned long nx842_get_desired_dma(struct vio_dev *viodev)
{
/* No use of DMA mappings within the driver. */
return 0;
}
struct nx842_slentry {
unsigned long ptr; /* Real address (use __pa()) */
unsigned long len;
};
/* pHyp scatterlist entry */
struct nx842_scatterlist {
int entry_nr; /* number of slentries */
struct nx842_slentry *entries; /* ptr to array of slentries */
};
/* Does not include sizeof(entry_nr) in the size */
static inline unsigned long nx842_get_scatterlist_size(
struct nx842_scatterlist *sl)
{
return sl->entry_nr * sizeof(struct nx842_slentry);
}
static inline unsigned long nx842_get_pa(void *addr)
{
if (is_vmalloc_addr(addr))
return page_to_phys(vmalloc_to_page(addr))
+ offset_in_page(addr);
else
return __pa(addr);
}
static int nx842_build_scatterlist(unsigned long buf, int len,
struct nx842_scatterlist *sl)
{
unsigned long nextpage;
struct nx842_slentry *entry;
sl->entry_nr = 0;
entry = sl->entries;
while (len) {
entry->ptr = nx842_get_pa((void *)buf);
nextpage = ALIGN(buf + 1, NX842_HW_PAGE_SIZE);
if (nextpage < buf + len) {
/* we aren't at the end yet */
if (IS_ALIGNED(buf, NX842_HW_PAGE_SIZE))
/* we are in the middle (or beginning) */
entry->len = NX842_HW_PAGE_SIZE;
else
/* we are at the beginning */
entry->len = nextpage - buf;
} else {
/* at the end */
entry->len = len;
}
len -= entry->len;
buf += entry->len;
sl->entry_nr++;
entry++;
}
return 0;
}
/*
* Working memory for software decompression
*/
struct sw842_fifo {
union {
char f8[256][8];
char f4[512][4];
};
char f2[256][2];
unsigned char f84_full;
unsigned char f2_full;
unsigned char f8_count;
unsigned char f2_count;
unsigned int f4_count;
};
/*
* Working memory for crypto API
*/
struct nx842_workmem {
char bounce[PAGE_SIZE]; /* bounce buffer for decompression input */
union {
/* hardware working memory */
struct {
/* scatterlist */
char slin[SIZE_4K];
char slout[SIZE_4K];
/* coprocessor status/parameter block */
struct nx_csbcpb csbcpb;
};
/* software working memory */
struct sw842_fifo swfifo; /* software decompression fifo */
};
};
int nx842_get_workmem_size(void)
{
return sizeof(struct nx842_workmem) + NX842_HW_PAGE_SIZE;
}
EXPORT_SYMBOL_GPL(nx842_get_workmem_size);
int nx842_get_workmem_size_aligned(void)
{
return sizeof(struct nx842_workmem);
}
EXPORT_SYMBOL_GPL(nx842_get_workmem_size_aligned);
static int nx842_validate_result(struct device *dev,
struct cop_status_block *csb)
{
/* The csb must be valid after returning from vio_h_cop_sync */
if (!NX842_CSBCBP_VALID_CHK(csb->valid)) {
dev_err(dev, "%s: cspcbp not valid upon completion.\n",
__func__);
dev_dbg(dev, "valid:0x%02x cs:0x%02x cc:0x%02x ce:0x%02x\n",
csb->valid,
csb->crb_seq_number,
csb->completion_code,
csb->completion_extension);
dev_dbg(dev, "processed_bytes:%d address:0x%016lx\n",
csb->processed_byte_count,
(unsigned long)csb->address);
return -EIO;
}
/* Check return values from the hardware in the CSB */
switch (csb->completion_code) {
case 0: /* Completed without error */
break;
case 64: /* Target bytes > Source bytes during compression */
case 13: /* Output buffer too small */
dev_dbg(dev, "%s: Compression output larger than input\n",
__func__);
return -ENOSPC;
case 66: /* Input data contains an illegal template field */
case 67: /* Template indicates data past the end of the input stream */
dev_dbg(dev, "%s: Bad data for decompression (code:%d)\n",
__func__, csb->completion_code);
return -EINVAL;
default:
dev_dbg(dev, "%s: Unspecified error (code:%d)\n",
__func__, csb->completion_code);
return -EIO;
}
/* Hardware sanity check */
if (!NX842_CSBCPB_CE2(csb->completion_extension)) {
dev_err(dev, "%s: No error returned by hardware, but "
"data returned is unusable, contact support.\n"
"(Additional info: csbcbp->processed bytes "
"does not specify processed bytes for the "
"target buffer.)\n", __func__);
return -EIO;
}
return 0;
}
/**
* nx842_compress - Compress data using the 842 algorithm
*
* Compression provide by the NX842 coprocessor on IBM Power systems.
* The input buffer is compressed and the result is stored in the
* provided output buffer.
*
* Upon return from this function @outlen contains the length of the
* compressed data. If there is an error then @outlen will be 0 and an
* error will be specified by the return code from this function.
*
* @in: Pointer to input buffer, must be page aligned
* @inlen: Length of input buffer, must be PAGE_SIZE
* @out: Pointer to output buffer
* @outlen: Length of output buffer
* @wrkmem: ptr to buffer for working memory, size determined by
* nx842_get_workmem_size()
*
* Returns:
* 0 Success, output of length @outlen stored in the buffer at @out
* -ENOMEM Unable to allocate internal buffers
* -ENOSPC Output buffer is to small
* -EMSGSIZE XXX Difficult to describe this limitation
* -EIO Internal error
* -ENODEV Hardware unavailable
*/
int nx842_compress(const unsigned char *in, unsigned int inlen,
unsigned char *out, unsigned int *outlen, void *wmem)
{
struct nx842_header *hdr;
struct nx842_devdata *local_devdata;
struct device *dev = NULL;
struct nx842_workmem *workmem;
struct nx842_scatterlist slin, slout;
struct nx_csbcpb *csbcpb;
int ret = 0, max_sync_size, i, bytesleft, size, hdrsize;
unsigned long inbuf, outbuf, padding;
struct vio_pfo_op op = {
.done = NULL,
.handle = 0,
.timeout = 0,
};
unsigned long start_time = get_tb();
/*
* Make sure input buffer is 64k page aligned. This is assumed since
* this driver is designed for page compression only (for now). This
* is very nice since we can now use direct DDE(s) for the input and
* the alignment is guaranteed.
*/
inbuf = (unsigned long)in;
if (!IS_ALIGNED(inbuf, PAGE_SIZE) || inlen != PAGE_SIZE)
return -EINVAL;
rcu_read_lock();
local_devdata = rcu_dereference(devdata);
if (!local_devdata || !local_devdata->dev) {
rcu_read_unlock();
return -ENODEV;
}
max_sync_size = local_devdata->max_sync_size;
dev = local_devdata->dev;
/* Create the header */
hdr = (struct nx842_header *)out;
hdr->blocks_nr = PAGE_SIZE / max_sync_size;
hdrsize = nx842_header_size(hdr);
outbuf = (unsigned long)out + hdrsize;
bytesleft = *outlen - hdrsize;
/* Init scatterlist */
workmem = (struct nx842_workmem *)ALIGN((unsigned long)wmem,
NX842_HW_PAGE_SIZE);
slin.entries = (struct nx842_slentry *)workmem->slin;
slout.entries = (struct nx842_slentry *)workmem->slout;
/* Init operation */
op.flags = NX842_OP_COMPRESS;
csbcpb = &workmem->csbcpb;
memset(csbcpb, 0, sizeof(*csbcpb));
op.csbcpb = nx842_get_pa(csbcpb);
op.out = nx842_get_pa(slout.entries);
for (i = 0; i < hdr->blocks_nr; i++) {
/*
* Aligning the output blocks to 128 bytes does waste space,
* but it prevents the need for bounce buffers and memory
* copies. It also simplifies the code a lot. In the worst
* case (64k page, 4k max_sync_size), you lose up to
* (128*16)/64k = ~3% the compression factor. For 64k
* max_sync_size, the loss would be at most 128/64k = ~0.2%.
*/
padding = ALIGN(outbuf, IO_BUFFER_ALIGN) - outbuf;
outbuf += padding;
bytesleft -= padding;
if (i == 0)
/* save offset into first block in header */
hdr->offset = padding + hdrsize;
if (bytesleft <= 0) {
ret = -ENOSPC;
goto unlock;
}
/*
* NOTE: If the default max_sync_size is changed from 4k
* to 64k, remove the "likely" case below, since a
* scatterlist will always be needed.
*/
if (likely(max_sync_size == NX842_HW_PAGE_SIZE)) {
/* Create direct DDE */
op.in = nx842_get_pa((void *)inbuf);
op.inlen = max_sync_size;
} else {
/* Create indirect DDE (scatterlist) */
nx842_build_scatterlist(inbuf, max_sync_size, &slin);
op.in = nx842_get_pa(slin.entries);
op.inlen = -nx842_get_scatterlist_size(&slin);
}
/*
* If max_sync_size != NX842_HW_PAGE_SIZE, an indirect
* DDE is required for the outbuf.
* If max_sync_size == NX842_HW_PAGE_SIZE, outbuf must
* also be page aligned (1 in 128/4k=32 chance) in order
* to use a direct DDE.
* This is unlikely, just use an indirect DDE always.
*/
nx842_build_scatterlist(outbuf,
min(bytesleft, max_sync_size), &slout);
/* op.out set before loop */
op.outlen = -nx842_get_scatterlist_size(&slout);
/* Send request to pHyp */
ret = vio_h_cop_sync(local_devdata->vdev, &op);
/* Check for pHyp error */
if (ret) {
dev_dbg(dev, "%s: vio_h_cop_sync error (ret=%d, hret=%ld)\n",
__func__, ret, op.hcall_err);
ret = -EIO;
goto unlock;
}
/* Check for hardware error */
ret = nx842_validate_result(dev, &csbcpb->csb);
if (ret && ret != -ENOSPC)
goto unlock;
/* Handle incompressible data */
if (unlikely(ret == -ENOSPC)) {
if (bytesleft < max_sync_size) {
/*
* Not enough space left in the output buffer
* to store uncompressed block
*/
goto unlock;
} else {
/* Store incompressible block */
memcpy((void *)outbuf, (void *)inbuf,
max_sync_size);
hdr->sizes[i] = -max_sync_size;
outbuf += max_sync_size;
bytesleft -= max_sync_size;
/* Reset ret, incompressible data handled */
ret = 0;
}
} else {
/* Normal case, compression was successful */
size = csbcpb->csb.processed_byte_count;
dev_dbg(dev, "%s: processed_bytes=%d\n",
__func__, size);
hdr->sizes[i] = size;
outbuf += size;
bytesleft -= size;
}
inbuf += max_sync_size;
}
*outlen = (unsigned int)(outbuf - (unsigned long)out);
unlock:
if (ret)
nx842_inc_comp_failed(local_devdata);
else {
nx842_inc_comp_complete(local_devdata);
ibm_nx842_incr_hist(local_devdata->counters->comp_times,
(get_tb() - start_time) / tb_ticks_per_usec);
}
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(nx842_compress);
static int sw842_decompress(const unsigned char *, int, unsigned char *, int *,
const void *);
/**
* nx842_decompress - Decompress data using the 842 algorithm
*
* Decompression provide by the NX842 coprocessor on IBM Power systems.
* The input buffer is decompressed and the result is stored in the
* provided output buffer. The size allocated to the output buffer is
* provided by the caller of this function in @outlen. Upon return from
* this function @outlen contains the length of the decompressed data.
* If there is an error then @outlen will be 0 and an error will be
* specified by the return code from this function.
*
* @in: Pointer to input buffer, will use bounce buffer if not 128 byte
* aligned
* @inlen: Length of input buffer
* @out: Pointer to output buffer, must be page aligned
* @outlen: Length of output buffer, must be PAGE_SIZE
* @wrkmem: ptr to buffer for working memory, size determined by
* nx842_get_workmem_size()
*
* Returns:
* 0 Success, output of length @outlen stored in the buffer at @out
* -ENODEV Hardware decompression device is unavailable
* -ENOMEM Unable to allocate internal buffers
* -ENOSPC Output buffer is to small
* -EINVAL Bad input data encountered when attempting decompress
* -EIO Internal error
*/
int nx842_decompress(const unsigned char *in, unsigned int inlen,
unsigned char *out, unsigned int *outlen, void *wmem)
{
struct nx842_header *hdr;
struct nx842_devdata *local_devdata;
struct device *dev = NULL;
struct nx842_workmem *workmem;
struct nx842_scatterlist slin, slout;
struct nx_csbcpb *csbcpb;
int ret = 0, i, size, max_sync_size;
unsigned long inbuf, outbuf;
struct vio_pfo_op op = {
.done = NULL,
.handle = 0,
.timeout = 0,
};
unsigned long start_time = get_tb();
/* Ensure page alignment and size */
outbuf = (unsigned long)out;
if (!IS_ALIGNED(outbuf, PAGE_SIZE) || *outlen != PAGE_SIZE)
return -EINVAL;
rcu_read_lock();
local_devdata = rcu_dereference(devdata);
if (local_devdata)
dev = local_devdata->dev;
/* Get header */
hdr = (struct nx842_header *)in;
workmem = (struct nx842_workmem *)ALIGN((unsigned long)wmem,
NX842_HW_PAGE_SIZE);
inbuf = (unsigned long)in + hdr->offset;
if (likely(!IS_ALIGNED(inbuf, IO_BUFFER_ALIGN))) {
/* Copy block(s) into bounce buffer for alignment */
memcpy(workmem->bounce, in + hdr->offset, inlen - hdr->offset);
inbuf = (unsigned long)workmem->bounce;
}
/* Init scatterlist */
slin.entries = (struct nx842_slentry *)workmem->slin;
slout.entries = (struct nx842_slentry *)workmem->slout;
/* Init operation */
op.flags = NX842_OP_DECOMPRESS;
csbcpb = &workmem->csbcpb;
memset(csbcpb, 0, sizeof(*csbcpb));
op.csbcpb = nx842_get_pa(csbcpb);
/*
* max_sync_size may have changed since compression,
* so we can't read it from the device info. We need
* to derive it from hdr->blocks_nr.
*/
max_sync_size = PAGE_SIZE / hdr->blocks_nr;
for (i = 0; i < hdr->blocks_nr; i++) {
/* Skip padding */
inbuf = ALIGN(inbuf, IO_BUFFER_ALIGN);
if (hdr->sizes[i] < 0) {
/* Negative sizes indicate uncompressed data blocks */
size = abs(hdr->sizes[i]);
memcpy((void *)outbuf, (void *)inbuf, size);
outbuf += size;
inbuf += size;
continue;
}
if (!dev)
goto sw;
/*
* The better the compression, the more likely the "likely"
* case becomes.
*/
if (likely((inbuf & NX842_HW_PAGE_MASK) ==
((inbuf + hdr->sizes[i] - 1) & NX842_HW_PAGE_MASK))) {
/* Create direct DDE */
op.in = nx842_get_pa((void *)inbuf);
op.inlen = hdr->sizes[i];
} else {
/* Create indirect DDE (scatterlist) */
nx842_build_scatterlist(inbuf, hdr->sizes[i] , &slin);
op.in = nx842_get_pa(slin.entries);
op.inlen = -nx842_get_scatterlist_size(&slin);
}
/*
* NOTE: If the default max_sync_size is changed from 4k
* to 64k, remove the "likely" case below, since a
* scatterlist will always be needed.
*/
if (likely(max_sync_size == NX842_HW_PAGE_SIZE)) {
/* Create direct DDE */
op.out = nx842_get_pa((void *)outbuf);
op.outlen = max_sync_size;
} else {
/* Create indirect DDE (scatterlist) */
nx842_build_scatterlist(outbuf, max_sync_size, &slout);
op.out = nx842_get_pa(slout.entries);
op.outlen = -nx842_get_scatterlist_size(&slout);
}
/* Send request to pHyp */
ret = vio_h_cop_sync(local_devdata->vdev, &op);
/* Check for pHyp error */
if (ret) {
dev_dbg(dev, "%s: vio_h_cop_sync error (ret=%d, hret=%ld)\n",
__func__, ret, op.hcall_err);
dev = NULL;
goto sw;
}
/* Check for hardware error */
ret = nx842_validate_result(dev, &csbcpb->csb);
if (ret) {
dev = NULL;
goto sw;
}
/* HW decompression success */
inbuf += hdr->sizes[i];
outbuf += csbcpb->csb.processed_byte_count;
continue;
sw:
/* software decompression */
size = max_sync_size;
ret = sw842_decompress(
(unsigned char *)inbuf, hdr->sizes[i],
(unsigned char *)outbuf, &size, wmem);
if (ret)
pr_debug("%s: sw842_decompress failed with %d\n",
__func__, ret);
if (ret) {
if (ret != -ENOSPC && ret != -EINVAL &&
ret != -EMSGSIZE)
ret = -EIO;
goto unlock;
}
/* SW decompression success */
inbuf += hdr->sizes[i];
outbuf += size;
}
*outlen = (unsigned int)(outbuf - (unsigned long)out);
unlock:
if (ret)
/* decompress fail */
nx842_inc_decomp_failed(local_devdata);
else {
if (!dev)
/* software decompress */
nx842_inc_swdecomp(local_devdata);
nx842_inc_decomp_complete(local_devdata);
ibm_nx842_incr_hist(local_devdata->counters->decomp_times,
(get_tb() - start_time) / tb_ticks_per_usec);
}
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(nx842_decompress);
/**
* nx842_OF_set_defaults -- Set default (disabled) values for devdata
*
* @devdata - struct nx842_devdata to update
*
* Returns:
* 0 on success
* -ENOENT if @devdata ptr is NULL
*/
static int nx842_OF_set_defaults(struct nx842_devdata *devdata)
{
if (devdata) {
devdata->max_sync_size = 0;
devdata->max_sync_sg = 0;
devdata->max_sg_len = 0;
devdata->status = UNAVAILABLE;
return 0;
} else
return -ENOENT;
}
/**
* nx842_OF_upd_status -- Update the device info from OF status prop
*
* The status property indicates if the accelerator is enabled. If the
* device is in the OF tree it indicates that the hardware is present.
* The status field indicates if the device is enabled when the status
* is 'okay'. Otherwise the device driver will be disabled.
*
* @devdata - struct nx842_devdata to update
* @prop - struct property point containing the maxsyncop for the update
*
* Returns:
* 0 - Device is available
* -EINVAL - Device is not available
*/
static int nx842_OF_upd_status(struct nx842_devdata *devdata,
struct property *prop) {
int ret = 0;
const char *status = (const char *)prop->value;
if (!strncmp(status, "okay", (size_t)prop->length)) {
devdata->status = AVAILABLE;
} else {
dev_info(devdata->dev, "%s: status '%s' is not 'okay'\n",
__func__, status);
devdata->status = UNAVAILABLE;
}
return ret;
}
/**
* nx842_OF_upd_maxsglen -- Update the device info from OF maxsglen prop
*
* Definition of the 'ibm,max-sg-len' OF property:
* This field indicates the maximum byte length of a scatter list
* for the platform facility. It is a single cell encoded as with encode-int.
*
* Example:
* # od -x ibm,max-sg-len
* 0000000 0000 0ff0
*
* In this example, the maximum byte length of a scatter list is
* 0x0ff0 (4,080).
*
* @devdata - struct nx842_devdata to update
* @prop - struct property point containing the maxsyncop for the update
*
* Returns:
* 0 on success
* -EINVAL on failure
*/
static int nx842_OF_upd_maxsglen(struct nx842_devdata *devdata,
struct property *prop) {
int ret = 0;
const int *maxsglen = prop->value;
if (prop->length != sizeof(*maxsglen)) {
dev_err(devdata->dev, "%s: unexpected format for ibm,max-sg-len property\n", __func__);
dev_dbg(devdata->dev, "%s: ibm,max-sg-len is %d bytes long, expected %lu bytes\n", __func__,
prop->length, sizeof(*maxsglen));
ret = -EINVAL;
} else {
devdata->max_sg_len = (unsigned int)min(*maxsglen,
(int)NX842_HW_PAGE_SIZE);
}
return ret;
}
/**
* nx842_OF_upd_maxsyncop -- Update the device info from OF maxsyncop prop
*
* Definition of the 'ibm,max-sync-cop' OF property:
* Two series of cells. The first series of cells represents the maximums
* that can be synchronously compressed. The second series of cells
* represents the maximums that can be synchronously decompressed.
* 1. The first cell in each series contains the count of the number of
* data length, scatter list elements pairs that follow – each being
* of the form
* a. One cell data byte length
* b. One cell total number of scatter list elements
*
* Example:
* # od -x ibm,max-sync-cop
* 0000000 0000 0001 0000 1000 0000 01fe 0000 0001
* 0000020 0000 1000 0000 01fe
*
* In this example, compression supports 0x1000 (4,096) data byte length
* and 0x1fe (510) total scatter list elements. Decompression supports
* 0x1000 (4,096) data byte length and 0x1f3 (510) total scatter list
* elements.
*
* @devdata - struct nx842_devdata to update
* @prop - struct property point containing the maxsyncop for the update
*
* Returns:
* 0 on success
* -EINVAL on failure
*/
static int nx842_OF_upd_maxsyncop(struct nx842_devdata *devdata,
struct property *prop) {
int ret = 0;
const struct maxsynccop_t {
int comp_elements;
int comp_data_limit;
int comp_sg_limit;
int decomp_elements;
int decomp_data_limit;
int decomp_sg_limit;
} *maxsynccop;
if (prop->length != sizeof(*maxsynccop)) {
dev_err(devdata->dev, "%s: unexpected format for ibm,max-sync-cop property\n", __func__);
dev_dbg(devdata->dev, "%s: ibm,max-sync-cop is %d bytes long, expected %lu bytes\n", __func__, prop->length,
sizeof(*maxsynccop));
ret = -EINVAL;
goto out;
}
maxsynccop = (const struct maxsynccop_t *)prop->value;
/* Use one limit rather than separate limits for compression and
* decompression. Set a maximum for this so as not to exceed the
* size that the header can support and round the value down to
* the hardware page size (4K) */
devdata->max_sync_size =
(unsigned int)min(maxsynccop->comp_data_limit,
maxsynccop->decomp_data_limit);
devdata->max_sync_size = min_t(unsigned int, devdata->max_sync_size,
SIZE_64K);
if (devdata->max_sync_size < SIZE_4K) {
dev_err(devdata->dev, "%s: hardware max data size (%u) is "
"less than the driver minimum, unable to use "
"the hardware device\n",
__func__, devdata->max_sync_size);
ret = -EINVAL;
goto out;
}
devdata->max_sync_sg = (unsigned int)min(maxsynccop->comp_sg_limit,
maxsynccop->decomp_sg_limit);
if (devdata->max_sync_sg < 1) {
dev_err(devdata->dev, "%s: hardware max sg size (%u) is "
"less than the driver minimum, unable to use "
"the hardware device\n",
__func__, devdata->max_sync_sg);
ret = -EINVAL;
goto out;
}
out:
return ret;
}
/**
*
* nx842_OF_upd -- Handle OF properties updates for the device.
*
* Set all properties from the OF tree. Optionally, a new property
* can be provided by the @new_prop pointer to overwrite an existing value.
* The device will remain disabled until all values are valid, this function
* will return an error for updates unless all values are valid.
*
* @new_prop: If not NULL, this property is being updated. If NULL, update
* all properties from the current values in the OF tree.
*
* Returns:
* 0 - Success
* -ENOMEM - Could not allocate memory for new devdata structure
* -EINVAL - property value not found, new_prop is not a recognized
* property for the device or property value is not valid.
* -ENODEV - Device is not available
*/
static int nx842_OF_upd(struct property *new_prop)
{
struct nx842_devdata *old_devdata = NULL;
struct nx842_devdata *new_devdata = NULL;
struct device_node *of_node = NULL;
struct property *status = NULL;
struct property *maxsglen = NULL;
struct property *maxsyncop = NULL;
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&devdata_mutex, flags);
old_devdata = rcu_dereference_check(devdata,
lockdep_is_held(&devdata_mutex));
if (old_devdata)
of_node = old_devdata->dev->of_node;
if (!old_devdata || !of_node) {
pr_err("%s: device is not available\n", __func__);
spin_unlock_irqrestore(&devdata_mutex, flags);
return -ENODEV;
}
new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS);
if (!new_devdata) {
dev_err(old_devdata->dev, "%s: Could not allocate memory for device data\n", __func__);
ret = -ENOMEM;
goto error_out;
}
memcpy(new_devdata, old_devdata, sizeof(*old_devdata));
new_devdata->counters = old_devdata->counters;
/* Set ptrs for existing properties */
status = of_find_property(of_node, "status", NULL);
maxsglen = of_find_property(of_node, "ibm,max-sg-len", NULL);
maxsyncop = of_find_property(of_node, "ibm,max-sync-cop", NULL);
if (!status || !maxsglen || !maxsyncop) {
dev_err(old_devdata->dev, "%s: Could not locate device properties\n", __func__);
ret = -EINVAL;
goto error_out;
}
/*
* If this is a property update, there are only certain properties that
* we care about. Bail if it isn't in the below list
*/
if (new_prop && (strncmp(new_prop->name, "status", new_prop->length) ||
strncmp(new_prop->name, "ibm,max-sg-len", new_prop->length) ||
strncmp(new_prop->name, "ibm,max-sync-cop", new_prop->length)))
goto out;
/* Perform property updates */
ret = nx842_OF_upd_status(new_devdata, status);
if (ret)
goto error_out;
ret = nx842_OF_upd_maxsglen(new_devdata, maxsglen);
if (ret)
goto error_out;
ret = nx842_OF_upd_maxsyncop(new_devdata, maxsyncop);
if (ret)
goto error_out;
out:
dev_info(old_devdata->dev, "%s: max_sync_size new:%u old:%u\n",
__func__, new_devdata->max_sync_size,
old_devdata->max_sync_size);
dev_info(old_devdata->dev, "%s: max_sync_sg new:%u old:%u\n",
__func__, new_devdata->max_sync_sg,
old_devdata->max_sync_sg);
dev_info(old_devdata->dev, "%s: max_sg_len new:%u old:%u\n",
__func__, new_devdata->max_sg_len,
old_devdata->max_sg_len);
rcu_assign_pointer(devdata, new_devdata);
spin_unlock_irqrestore(&devdata_mutex, flags);
synchronize_rcu();
dev_set_drvdata(new_devdata->dev, new_devdata);
kfree(old_devdata);
return 0;
error_out:
if (new_devdata) {
dev_info(old_devdata->dev, "%s: device disabled\n", __func__);
nx842_OF_set_defaults(new_devdata);
rcu_assign_pointer(devdata, new_devdata);
spin_unlock_irqrestore(&devdata_mutex, flags);
synchronize_rcu();
dev_set_drvdata(new_devdata->dev, new_devdata);
kfree(old_devdata);
} else {
dev_err(old_devdata->dev, "%s: could not update driver from hardware\n", __func__);
spin_unlock_irqrestore(&devdata_mutex, flags);
}
if (!ret)
ret = -EINVAL;
return ret;
}
/**
* nx842_OF_notifier - Process updates to OF properties for the device
*
* @np: notifier block
* @action: notifier action
* @update: struct pSeries_reconfig_prop_update pointer if action is
* PSERIES_UPDATE_PROPERTY
*
* Returns:
* NOTIFY_OK on success
* NOTIFY_BAD encoded with error number on failure, use
* notifier_to_errno() to decode this value
*/
static int nx842_OF_notifier(struct notifier_block *np, unsigned long action,
void *data)
{
struct of_reconfig_data *upd = data;
struct nx842_devdata *local_devdata;
struct device_node *node = NULL;
rcu_read_lock();
local_devdata = rcu_dereference(devdata);
if (local_devdata)
node = local_devdata->dev->of_node;
if (local_devdata &&
action == OF_RECONFIG_UPDATE_PROPERTY &&
!strcmp(upd->dn->name, node->name)) {
rcu_read_unlock();
nx842_OF_upd(upd->prop);
} else
rcu_read_unlock();
return NOTIFY_OK;
}
static struct notifier_block nx842_of_nb = {
.notifier_call = nx842_OF_notifier,
};
#define nx842_counter_read(_name) \
static ssize_t nx842_##_name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) { \
struct nx842_devdata *local_devdata; \
int p = 0; \
rcu_read_lock(); \
local_devdata = rcu_dereference(devdata); \
if (local_devdata) \
p = snprintf(buf, PAGE_SIZE, "%ld\n", \
atomic64_read(&local_devdata->counters->_name)); \
rcu_read_unlock(); \
return p; \
}
#define NX842DEV_COUNTER_ATTR_RO(_name) \
nx842_counter_read(_name); \
static struct device_attribute dev_attr_##_name = __ATTR(_name, \
0444, \
nx842_##_name##_show,\
NULL);
NX842DEV_COUNTER_ATTR_RO(comp_complete);
NX842DEV_COUNTER_ATTR_RO(comp_failed);
NX842DEV_COUNTER_ATTR_RO(decomp_complete);
NX842DEV_COUNTER_ATTR_RO(decomp_failed);
NX842DEV_COUNTER_ATTR_RO(swdecomp);
static ssize_t nx842_timehist_show(struct device *,
struct device_attribute *, char *);
static struct device_attribute dev_attr_comp_times = __ATTR(comp_times, 0444,
nx842_timehist_show, NULL);
static struct device_attribute dev_attr_decomp_times = __ATTR(decomp_times,
0444, nx842_timehist_show, NULL);
static ssize_t nx842_timehist_show(struct device *dev,
struct device_attribute *attr, char *buf) {
char *p = buf;
struct nx842_devdata *local_devdata;
atomic64_t *times;
int bytes_remain = PAGE_SIZE;
int bytes;
int i;
rcu_read_lock();
local_devdata = rcu_dereference(devdata);
if (!local_devdata) {
rcu_read_unlock();
return 0;
}
if (attr == &dev_attr_comp_times)
times = local_devdata->counters->comp_times;
else if (attr == &dev_attr_decomp_times)
times = local_devdata->counters->decomp_times;
else {
rcu_read_unlock();
return 0;
}
for (i = 0; i < (NX842_HIST_SLOTS - 2); i++) {
bytes = snprintf(p, bytes_remain, "%u-%uus:\t%ld\n",
i ? (2<<(i-1)) : 0, (2<<i)-1,
atomic64_read(×[i]));
bytes_remain -= bytes;
p += bytes;
}
/* The last bucket holds everything over
* 2<<(NX842_HIST_SLOTS - 2) us */
bytes = snprintf(p, bytes_remain, "%uus - :\t%ld\n",
2<<(NX842_HIST_SLOTS - 2),
atomic64_read(×[(NX842_HIST_SLOTS - 1)]));
p += bytes;
rcu_read_unlock();
return p - buf;
}
static struct attribute *nx842_sysfs_entries[] = {
&dev_attr_comp_complete.attr,
&dev_attr_comp_failed.attr,
&dev_attr_decomp_complete.attr,
&dev_attr_decomp_failed.attr,
&dev_attr_swdecomp.attr,
&dev_attr_comp_times.attr,
&dev_attr_decomp_times.attr,
NULL,
};
static struct attribute_group nx842_attribute_group = {
.name = NULL, /* put in device directory */
.attrs = nx842_sysfs_entries,
};
static int __init nx842_probe(struct vio_dev *viodev,
const struct vio_device_id *id)
{
struct nx842_devdata *old_devdata, *new_devdata = NULL;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&devdata_mutex, flags);
old_devdata = rcu_dereference_check(devdata,
lockdep_is_held(&devdata_mutex));
if (old_devdata && old_devdata->vdev != NULL) {
dev_err(&viodev->dev, "%s: Attempt to register more than one instance of the hardware\n", __func__);
ret = -1;
goto error_unlock;
}
dev_set_drvdata(&viodev->dev, NULL);
new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS);
if (!new_devdata) {
dev_err(&viodev->dev, "%s: Could not allocate memory for device data\n", __func__);
ret = -ENOMEM;
goto error_unlock;
}
new_devdata->counters = kzalloc(sizeof(*new_devdata->counters),
GFP_NOFS);
if (!new_devdata->counters) {
dev_err(&viodev->dev, "%s: Could not allocate memory for performance counters\n", __func__);
ret = -ENOMEM;
goto error_unlock;
}
new_devdata->vdev = viodev;
new_devdata->dev = &viodev->dev;
nx842_OF_set_defaults(new_devdata);
rcu_assign_pointer(devdata, new_devdata);
spin_unlock_irqrestore(&devdata_mutex, flags);
synchronize_rcu();
kfree(old_devdata);
of_reconfig_notifier_register(&nx842_of_nb);
ret = nx842_OF_upd(NULL);
if (ret && ret != -ENODEV) {
dev_err(&viodev->dev, "could not parse device tree. %d\n", ret);
ret = -1;
goto error;
}
rcu_read_lock();
dev_set_drvdata(&viodev->dev, rcu_dereference(devdata));
rcu_read_unlock();
if (sysfs_create_group(&viodev->dev.kobj, &nx842_attribute_group)) {
dev_err(&viodev->dev, "could not create sysfs device attributes\n");
ret = -1;
goto error;
}
return 0;
error_unlock:
spin_unlock_irqrestore(&devdata_mutex, flags);
if (new_devdata)
kfree(new_devdata->counters);
kfree(new_devdata);
error:
return ret;
}
static int __exit nx842_remove(struct vio_dev *viodev)
{
struct nx842_devdata *old_devdata;
unsigned long flags;
pr_info("Removing IBM Power 842 compression device\n");
sysfs_remove_group(&viodev->dev.kobj, &nx842_attribute_group);
spin_lock_irqsave(&devdata_mutex, flags);
old_devdata = rcu_dereference_check(devdata,
lockdep_is_held(&devdata_mutex));
of_reconfig_notifier_unregister(&nx842_of_nb);
RCU_INIT_POINTER(devdata, NULL);
spin_unlock_irqrestore(&devdata_mutex, flags);
synchronize_rcu();
dev_set_drvdata(&viodev->dev, NULL);
if (old_devdata)
kfree(old_devdata->counters);
kfree(old_devdata);
return 0;
}
static struct vio_device_id nx842_driver_ids[] = {
{"ibm,compression-v1", "ibm,compression"},
{"", ""},
};
static struct vio_driver nx842_driver = {
.name = MODULE_NAME,
.probe = nx842_probe,
.remove = __exit_p(nx842_remove),
.get_desired_dma = nx842_get_desired_dma,
.id_table = nx842_driver_ids,
};
static int __init nx842_init(void)
{
struct nx842_devdata *new_devdata;
pr_info("Registering IBM Power 842 compression driver\n");
RCU_INIT_POINTER(devdata, NULL);
new_devdata = kzalloc(sizeof(*new_devdata), GFP_KERNEL);
if (!new_devdata) {
pr_err("Could not allocate memory for device data\n");
return -ENOMEM;
}
new_devdata->status = UNAVAILABLE;
RCU_INIT_POINTER(devdata, new_devdata);
return vio_register_driver(&nx842_driver);
}
module_init(nx842_init);
static void __exit nx842_exit(void)
{
struct nx842_devdata *old_devdata;
unsigned long flags;
pr_info("Exiting IBM Power 842 compression driver\n");
spin_lock_irqsave(&devdata_mutex, flags);
old_devdata = rcu_dereference_check(devdata,
lockdep_is_held(&devdata_mutex));
RCU_INIT_POINTER(devdata, NULL);
spin_unlock_irqrestore(&devdata_mutex, flags);
synchronize_rcu();
if (old_devdata)
dev_set_drvdata(old_devdata->dev, NULL);
kfree(old_devdata);
vio_unregister_driver(&nx842_driver);
}
module_exit(nx842_exit);
/*********************************
* 842 software decompressor
*********************************/
typedef int (*sw842_template_op)(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_data8(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_data4(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_data2(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_ptr8(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_ptr4(const char **, int *, unsigned char **,
struct sw842_fifo *);
static int sw842_ptr2(const char **, int *, unsigned char **,
struct sw842_fifo *);
/* special templates */
#define SW842_TMPL_REPEAT 0x1B
#define SW842_TMPL_ZEROS 0x1C
#define SW842_TMPL_EOF 0x1E
static sw842_template_op sw842_tmpl_ops[26][4] = {
{ sw842_data8, NULL}, /* 0 (00000) */
{ sw842_data4, sw842_data2, sw842_ptr2, NULL},
{ sw842_data4, sw842_ptr2, sw842_data2, NULL},
{ sw842_data4, sw842_ptr2, sw842_ptr2, NULL},
{ sw842_data4, sw842_ptr4, NULL},
{ sw842_data2, sw842_ptr2, sw842_data4, NULL},
{ sw842_data2, sw842_ptr2, sw842_data2, sw842_ptr2},
{ sw842_data2, sw842_ptr2, sw842_ptr2, sw842_data2},
{ sw842_data2, sw842_ptr2, sw842_ptr2, sw842_ptr2,},
{ sw842_data2, sw842_ptr2, sw842_ptr4, NULL},
{ sw842_ptr2, sw842_data2, sw842_data4, NULL}, /* 10 (01010) */
{ sw842_ptr2, sw842_data4, sw842_ptr2, NULL},
{ sw842_ptr2, sw842_data2, sw842_ptr2, sw842_data2},
{ sw842_ptr2, sw842_data2, sw842_ptr2, sw842_ptr2},
{ sw842_ptr2, sw842_data2, sw842_ptr4, NULL},
{ sw842_ptr2, sw842_ptr2, sw842_data4, NULL},
{ sw842_ptr2, sw842_ptr2, sw842_data2, sw842_ptr2},
{ sw842_ptr2, sw842_ptr2, sw842_ptr2, sw842_data2},
{ sw842_ptr2, sw842_ptr2, sw842_ptr2, sw842_ptr2},
{ sw842_ptr2, sw842_ptr2, sw842_ptr4, NULL},
{ sw842_ptr4, sw842_data4, NULL}, /* 20 (10100) */
{ sw842_ptr4, sw842_data2, sw842_ptr2, NULL},
{ sw842_ptr4, sw842_ptr2, sw842_data2, NULL},
{ sw842_ptr4, sw842_ptr2, sw842_ptr2, NULL},
{ sw842_ptr4, sw842_ptr4, NULL},
{ sw842_ptr8, NULL}
};
/* Software decompress helpers */
static uint8_t sw842_get_byte(const char *buf, int bit)
{
uint8_t tmpl;
uint16_t tmp;
tmp = htons(*(uint16_t *)(buf));
tmp = (uint16_t)(tmp << bit);
tmp = ntohs(tmp);
memcpy(&tmpl, &tmp, 1);
return tmpl;
}
static uint8_t sw842_get_template(const char **buf, int *bit)
{
uint8_t byte;
byte = sw842_get_byte(*buf, *bit);
byte = byte >> 3;
byte &= 0x1F;
*buf += (*bit + 5) / 8;
*bit = (*bit + 5) % 8;
return byte;
}
/* repeat_count happens to be 5-bit too (like the template) */
static uint8_t sw842_get_repeat_count(const char **buf, int *bit)
{
uint8_t byte;
byte = sw842_get_byte(*buf, *bit);
byte = byte >> 2;
byte &= 0x3F;
*buf += (*bit + 6) / 8;
*bit = (*bit + 6) % 8;
return byte;
}
static uint8_t sw842_get_ptr2(const char **buf, int *bit)
{
uint8_t ptr;
ptr = sw842_get_byte(*buf, *bit);
(*buf)++;
return ptr;
}
static uint16_t sw842_get_ptr4(const char **buf, int *bit,
struct sw842_fifo *fifo)
{
uint16_t ptr;
ptr = htons(*(uint16_t *)(*buf));
ptr = (uint16_t)(ptr << *bit);
ptr = ptr >> 7;
ptr &= 0x01FF;
*buf += (*bit + 9) / 8;
*bit = (*bit + 9) % 8;
return ptr;
}
static uint8_t sw842_get_ptr8(const char **buf, int *bit,
struct sw842_fifo *fifo)
{
return sw842_get_ptr2(buf, bit);
}
/* Software decompress template ops */
static int sw842_data8(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
int ret;
ret = sw842_data4(inbuf, inbit, outbuf, fifo);
if (ret)
return ret;
ret = sw842_data4(inbuf, inbit, outbuf, fifo);
return ret;
}
static int sw842_data4(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
int ret;
ret = sw842_data2(inbuf, inbit, outbuf, fifo);
if (ret)
return ret;
ret = sw842_data2(inbuf, inbit, outbuf, fifo);
return ret;
}
static int sw842_data2(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
**outbuf = sw842_get_byte(*inbuf, *inbit);
(*inbuf)++;
(*outbuf)++;
**outbuf = sw842_get_byte(*inbuf, *inbit);
(*inbuf)++;
(*outbuf)++;
return 0;
}
static int sw842_ptr8(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
uint8_t ptr;
ptr = sw842_get_ptr8(inbuf, inbit, fifo);
if (!fifo->f84_full && (ptr >= fifo->f8_count))
return 1;
memcpy(*outbuf, fifo->f8[ptr], 8);
*outbuf += 8;
return 0;
}
static int sw842_ptr4(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
uint16_t ptr;
ptr = sw842_get_ptr4(inbuf, inbit, fifo);
if (!fifo->f84_full && (ptr >= fifo->f4_count))
return 1;
memcpy(*outbuf, fifo->f4[ptr], 4);
*outbuf += 4;
return 0;
}
static int sw842_ptr2(const char **inbuf, int *inbit,
unsigned char **outbuf, struct sw842_fifo *fifo)
{
uint8_t ptr;
ptr = sw842_get_ptr2(inbuf, inbit);
if (!fifo->f2_full && (ptr >= fifo->f2_count))
return 1;
memcpy(*outbuf, fifo->f2[ptr], 2);
*outbuf += 2;
return 0;
}
static void sw842_copy_to_fifo(const char *buf, struct sw842_fifo *fifo)
{
unsigned char initial_f2count = fifo->f2_count;
memcpy(fifo->f8[fifo->f8_count], buf, 8);
fifo->f4_count += 2;
fifo->f8_count += 1;
if (!fifo->f84_full && fifo->f4_count >= 512) {
fifo->f84_full = 1;
fifo->f4_count /= 512;
}
memcpy(fifo->f2[fifo->f2_count++], buf, 2);
memcpy(fifo->f2[fifo->f2_count++], buf + 2, 2);
memcpy(fifo->f2[fifo->f2_count++], buf + 4, 2);
memcpy(fifo->f2[fifo->f2_count++], buf + 6, 2);
if (fifo->f2_count < initial_f2count)
fifo->f2_full = 1;
}
static int sw842_decompress(const unsigned char *src, int srclen,
unsigned char *dst, int *destlen,
const void *wrkmem)
{
uint8_t tmpl;
const char *inbuf;
int inbit = 0;
unsigned char *outbuf, *outbuf_end, *origbuf, *prevbuf;
const char *inbuf_end;
sw842_template_op op;
int opindex;
int i, repeat_count;
struct sw842_fifo *fifo;
int ret = 0;
fifo = &((struct nx842_workmem *)(wrkmem))->swfifo;
memset(fifo, 0, sizeof(*fifo));
origbuf = NULL;
inbuf = src;
inbuf_end = src + srclen;
outbuf = dst;
outbuf_end = dst + *destlen;
while ((tmpl = sw842_get_template(&inbuf, &inbit)) != SW842_TMPL_EOF) {
if (inbuf >= inbuf_end) {
ret = -EINVAL;
goto out;
}
opindex = 0;
prevbuf = origbuf;
origbuf = outbuf;
switch (tmpl) {
case SW842_TMPL_REPEAT:
if (prevbuf == NULL) {
ret = -EINVAL;
goto out;
}
repeat_count = sw842_get_repeat_count(&inbuf,
&inbit) + 1;
/* Did the repeat count advance past the end of input */
if (inbuf > inbuf_end) {
ret = -EINVAL;
goto out;
}
for (i = 0; i < repeat_count; i++) {
/* Would this overflow the output buffer */
if ((outbuf + 8) > outbuf_end) {
ret = -ENOSPC;
goto out;
}
memcpy(outbuf, prevbuf, 8);
sw842_copy_to_fifo(outbuf, fifo);
outbuf += 8;
}
break;
case SW842_TMPL_ZEROS:
/* Would this overflow the output buffer */
if ((outbuf + 8) > outbuf_end) {
ret = -ENOSPC;
goto out;
}
memset(outbuf, 0, 8);
sw842_copy_to_fifo(outbuf, fifo);
outbuf += 8;
break;
default:
if (tmpl > 25) {
ret = -EINVAL;
goto out;
}
/* Does this go past the end of the input buffer */
if ((inbuf + 2) > inbuf_end) {
ret = -EINVAL;
goto out;
}
/* Would this overflow the output buffer */
if ((outbuf + 8) > outbuf_end) {
ret = -ENOSPC;
goto out;
}
while (opindex < 4 &&
(op = sw842_tmpl_ops[tmpl][opindex++])
!= NULL) {
ret = (*op)(&inbuf, &inbit, &outbuf, fifo);
if (ret) {
ret = -EINVAL;
goto out;
}
sw842_copy_to_fifo(origbuf, fifo);
}
}
}
out:
if (!ret)
*destlen = (unsigned int)(outbuf - dst);
else
*destlen = 0;
return ret;
}