Re: [patch] PM / Hibernate: NULL dereferences on error paths

Bojan Smojver
2011-10-08T10:28:48Z

On Sat, 2011-10-08 at 07:58 +1100, Bojan Smojver wrote:
> Thanks - good catch. I'm an idiot. Will fix.

Here it is:
----------------------------------
kernel/power/swap.c | 632 ++++++++++++++++++++++++++++++++++++++-------------
1 files changed, 470 insertions(+), 162 deletions(-)

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 7c97c3a..61184fb 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -27,6 +27,9 @@
#include <linux/slab.h>
#include <linux/lzo.h>
#include <linux/vmalloc.h>
+#include <linux/cpumask.h>
+#include <linux/atomic.h>
+#include <linux/kthread.h>

#include "power.h"

@@ -43,8 +46,7 @@
* allocated and populated one at a time, so we only need one memory
* page to set up the entire structure.
*
- * During resume we also only need to use one swap_map_page structure
- * at a time.
+ * During resume we pick up all swap_map_page structures into a list.
*/

#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
@@ -54,6 +56,11 @@ struct swap_map_page {
sector_t next_swap;
};

+struct swap_map_page_list {
+ struct swap_map_page *map;
+ struct swap_map_page_list *next;
+};
+
/**
* The swap_map_handle structure is used for handling swap in
* a file-alike way
@@ -61,9 +68,11 @@ struct swap_map_page {

struct swap_map_handle {
struct swap_map_page *cur;
+ struct swap_map_page_list *maps;
sector_t cur_swap;
sector_t first_sector;
unsigned int k;
+ unsigned long nr_free_pages, written;
};

struct swsusp_header {
@@ -245,6 +254,7 @@ static int swsusp_swap_check(void)
static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
{
void *src;
+ int ret;

if (!offset)
return -ENOSPC;
@@ -254,9 +264,17 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
if (src) {
copy_page(src, buf);
} else {
- WARN_ON_ONCE(1);
- bio_chain = NULL; /* Go synchronous */
- src = buf;
+ ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */
+ if (ret)
+ return ret;
+ src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ WARN_ON_ONCE(1);
+ bio_chain = NULL; /* Go synchronous */
+ src = buf;
+ }
}
} else {
src = buf;
@@ -293,6 +311,8 @@ static int get_swap_writer(struct swap_map_handle *handle)
goto err_rel;
}
handle->k = 0;
+ handle->nr_free_pages = nr_free_pages();
+ handle->written = 0;
handle->first_sector = handle->cur_swap;
return 0;
err_rel:
@@ -316,20 +336,23 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
return error;
handle->cur->entries[handle->k++] = offset;
if (handle->k >= MAP_PAGE_ENTRIES) {
- error = hib_wait_on_bio_chain(bio_chain);
- if (error)
- goto out;
offset = alloc_swapdev_block(root_swap);
if (!offset)
return -ENOSPC;
handle->cur->next_swap = offset;
- error = write_page(handle->cur, handle->cur_swap, NULL);
+ error = write_page(handle->cur, handle->cur_swap, bio_chain);
if (error)
goto out;
clear_page(handle->cur);
handle->cur_swap = offset;
handle->k = 0;
}
+ if (++handle->written > (handle->nr_free_pages >> 1)) {
+ error = hib_wait_on_bio_chain(bio_chain);
+ if (error)
+ goto out;
+ handle->written = 0;
+ }
out:
return error;
}
@@ -372,6 +395,13 @@ static int swap_writer_finish(struct swap_map_handle *handle,
LZO_HEADER, PAGE_SIZE)
#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)

+/* Maximum number of threads for compression/decompression. */
+#define LZO_THREADS 3
+
+/* Maximum number of pages for read buffering. */
+#define LZO_READ_PAGES (MAP_PAGE_ENTRIES * 4)
+
+
/**
* save_image - save the suspend image data
*/
@@ -419,6 +449,50 @@ static int save_image(struct swap_map_handle *handle,
return ret;
}

+/**
+ * Structure used for LZO data compression.
+ */
+struct cmp_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start compression */
+ wait_queue_head_t done; /* compression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+ unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
+};
+
+/**
+ * Compression function that runs in its own thread.
+ */
+static int lzo_compress_threadfn(void *data)
+{
+ struct cmp_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->ret = lzo1x_1_compress(d->unc, d->unc_len,
+ d->cmp + LZO_HEADER, &d->cmp_len,
+ d->wrk);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}

/**
* save_image_lzo - Save the suspend image data compressed with LZO.
@@ -437,42 +511,65 @@ static int save_image_lzo(struct swap_map_handle *handle,
struct bio *bio;
struct timeval start;
struct timeval stop;
- size_t off, unc_len, cmp_len;
- unsigned char *unc, *cmp, *wrk, *page;
+ size_t off, thr, run_threads, nr_threads;
+ unsigned char *page = NULL;
+ struct cmp_data *data = NULL;
+
+ /*
+ * We'll limit the number of threads for compression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ if (nr_threads > LZO_THREADS)
+ nr_threads = LZO_THREADS;
+ else if (nr_threads < 1)
+ nr_threads = 1;

page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
if (!page) {
printk(KERN_ERR "PM: Failed to allocate LZO page\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_clean;
}

- wrk = vmalloc(LZO1X_1_MEM_COMPRESS);
- if (!wrk) {
- printk(KERN_ERR "PM: Failed to allocate LZO workspace\n");
- free_page((unsigned long)page);
- return -ENOMEM;
+ data = vmalloc(sizeof(*data) * nr_threads);
+ if (!data) {
+ printk(KERN_ERR "PM: Failed to allocate LZO data\n");
+ ret = -ENOMEM;
+ goto out_clean;
}
-
- unc = vmalloc(LZO_UNC_SIZE);
- if (!unc) {
- printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
- vfree(wrk);
- free_page((unsigned long)page);
- return -ENOMEM;
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct cmp_data, go));
+
+ /*
+ * Start the compression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_compress_threadfn,
+ &data[thr],
+ "image_compress/%zu", thr);
+ if (IS_ERR(data[thr].thr)) {
+ nr_threads = thr;
+ printk(KERN_ERR
+ "PM: Cannot start compression threads\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
}

- cmp = vmalloc(LZO_CMP_SIZE);
- if (!cmp) {
- printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
- vfree(unc);
- vfree(wrk);
- free_page((unsigned long)page);
- return -ENOMEM;
- }
+ /*
+ * Adjust number of free pages after all allocations have been done.
+ * We don't want to run out of pages when writing.
+ */
+ handle->nr_free_pages = nr_free_pages();

printk(KERN_INFO
+ "PM: Using %zu thread(s) for compression.\n"
"PM: Compressing and saving image data (%u pages) ... ",
- nr_to_write);
+ nr_threads, nr_to_write);
m = nr_to_write / 100;
if (!m)
m = 1;
@@ -480,54 +577,75 @@ static int save_image_lzo(struct swap_map_handle *handle,
bio = NULL;
do_gettimeofday(&start);
for (;;) {
- for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
- ret = snapshot_read_next(snapshot);
- if (ret < 0)
- goto out_finish;
-
- if (!ret)
+ for (thr = 0; thr < nr_threads; thr++) {
+ for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
+ ret = snapshot_read_next(snapshot);
+ if (ret < 0)
+ goto out_finish;
+
+ if (!ret)
+ break;
+
+ memcpy(data[thr].unc + off,
+ data_of(*snapshot), PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ printk(KERN_CONT "\b\b\b\b%3d%%",
+ nr_pages / m);
+ nr_pages++;
+ }
+ if (!off)
break;

- memcpy(unc + off, data_of(*snapshot), PAGE_SIZE);
+ data[thr].unc_len = off;

- if (!(nr_pages % m))
- printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
- nr_pages++;
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
}

- if (!off)
- break;
-
- unc_len = off;
- ret = lzo1x_1_compress(unc, unc_len,
- cmp + LZO_HEADER, &cmp_len, wrk);
- if (ret < 0) {
- printk(KERN_ERR "PM: LZO compression failed\n");
+ if (!thr)
break;
- }

- if (unlikely(!cmp_len ||
- cmp_len > lzo1x_worst_compress(unc_len))) {
- printk(KERN_ERR "PM: Invalid LZO compressed length\n");
- ret = -1;
- break;
- }
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);

- *(size_t *)cmp = cmp_len;
+ ret = data[thr].ret;

- /*
- * Given we are writing one page at a time to disk, we copy
- * that much from the buffer, although the last bit will likely
- * be smaller than full page. This is OK - we saved the length
- * of the compressed data, so any garbage at the end will be
- * discarded when we read it.
- */
- for (off = 0; off < LZO_HEADER + cmp_len; off += PAGE_SIZE) {
- memcpy(page, cmp + off, PAGE_SIZE);
+ if (ret < 0) {
+ printk(KERN_ERR "PM: LZO compression failed\n");
+ goto out_finish;
+ }

- ret = swap_write_page(handle, page, &bio);
- if (ret)
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(data[thr].unc_len))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO compressed length\n");
+ ret = -1;
goto out_finish;
+ }
+
+ *(size_t *)data[thr].cmp = data[thr].cmp_len;
+
+ /*
+ * Given we are writing one page at a time to disk, we
+ * copy that much from the buffer, although the last
+ * bit will likely be smaller than full page. This is
+ * OK - we saved the length of the compressed data, so
+ * any garbage at the end will be discarded when we
+ * read it.
+ */
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(page, data[thr].cmp + off, PAGE_SIZE);
+
+ ret = swap_write_page(handle, page, &bio);
+ if (ret)
+ goto out_finish;
+ }
}
}

@@ -541,11 +659,15 @@ out_finish:
else
printk(KERN_CONT "\n");
swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
-
- vfree(cmp);
- vfree(unc);
- vfree(wrk);
- free_page((unsigned long)page);
+out_clean:
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++) {
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ }
+ vfree(data);
+ }
+ if (page) free_page((unsigned long)page);

return ret;
}
@@ -625,31 +747,65 @@ out_finish:

static void release_swap_reader(struct swap_map_handle *handle)
{
+ struct swap_map_page_list *tmp;
+
if (handle->cur)
free_page((unsigned long)handle->cur);
+ while (handle->maps) {
+ if (handle->maps->map)
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ vfree(tmp);
+ }
handle->cur = NULL;
+ handle->maps = NULL;
}

static int get_swap_reader(struct swap_map_handle *handle,
unsigned int *flags_p)
{
int error;
+ struct swap_map_page_list *tmp, *last;
+ sector_t offset;

*flags_p = swsusp_header->flags;

if (!swsusp_header->image) /* how can this happen? */
return -EINVAL;

- handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH);
- if (!handle->cur)
- return -ENOMEM;
+ handle->cur = NULL;
+ last = handle->maps = NULL;
+ offset = swsusp_header->image;
+ while (offset) {
+ tmp = vmalloc(sizeof(*handle->maps));
+ if (!tmp) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+ memset(tmp, 0, sizeof(*tmp));
+ if (!handle->maps)
+ handle->maps = tmp;
+ if (last)
+ last->next = tmp;
+ last = tmp;
+
+ tmp->map = (struct swap_map_page *)
+ __get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (!tmp->map) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }

- error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
- if (error) {
- release_swap_reader(handle);
- return error;
+ error = hib_bio_read_page(offset, tmp->map, NULL);
+ if (error) {
+ release_swap_reader(handle);
+ return error;
+ }
+ offset = tmp->map->next_swap;
}
handle->k = 0;
+ handle->cur = handle->maps->map;
return 0;
}

@@ -658,6 +814,7 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
{
sector_t offset;
int error;
+ struct swap_map_page_list *tmp;

if (!handle->cur)
return -EINVAL;
@@ -668,13 +825,15 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
if (error)
return error;
if (++handle->k >= MAP_PAGE_ENTRIES) {
- error = hib_wait_on_bio_chain(bio_chain);
handle->k = 0;
- offset = handle->cur->next_swap;
- if (!offset)
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ vfree(tmp);
+ if (!handle->maps)
release_swap_reader(handle);
- else if (!error)
- error = hib_bio_read_page(offset, handle->cur, NULL);
+ else
+ handle->cur = handle->maps->map;
}
return error;
}
@@ -743,6 +902,50 @@ static int load_image(struct swap_map_handle *handle,
}

/**
+ * Structure used for LZO data decompression.
+ */
+struct dec_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start decompression */
+ wait_queue_head_t done; /* decompression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+};
+
+/**
+ * Deompression function that runs in its own thread.
+ */
+static int lzo_decompress_threadfn(void *data)
+{
+ struct dec_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->unc_len = LZO_UNC_SIZE;
+ d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
+ d->unc, &d->unc_len);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+
+/**
* load_image_lzo - Load compressed image data and decompress them with LZO.
* @handle: Swap map handle to use for loading data.
* @snapshot: Image to copy uncompressed data into.
@@ -754,49 +957,81 @@ static int load_image_lzo(struct swap_map_handle *handle,
{
unsigned int m;
int error = 0;
+ int eof = 0;
struct bio *bio;
struct timeval start;
struct timeval stop;
unsigned nr_pages;
- size_t i, off, unc_len, cmp_len;
- unsigned char *unc, *cmp, *page[LZO_CMP_PAGES];
-
- for (i = 0; i < LZO_CMP_PAGES; i++) {
- page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
- if (!page[i]) {
- printk(KERN_ERR "PM: Failed to allocate LZO page\n");
-
- while (i)
- free_page((unsigned long)page[--i]);
-
- return -ENOMEM;
- }
+ size_t i, off, thr, run_threads, nr_threads;
+ size_t ring = 0, pg = 0, ring_size = 0, have = 0, want, need, asked = 0;
+ unsigned char **page = NULL;
+ struct dec_data *data = NULL;
+
+ /*
+ * We'll limit the number of threads for decompression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ if (nr_threads > LZO_THREADS)
+ nr_threads = LZO_THREADS;
+ else if (nr_threads < 1)
+ nr_threads = 1;
+
+ page = vmalloc(sizeof(*page) * LZO_READ_PAGES);
+ if (!page) {
+ printk(KERN_ERR "PM: Failed to allocate LZO page\n");
+ error = -ENOMEM;
+ goto out_clean;
}

- unc = vmalloc(LZO_UNC_SIZE);
- if (!unc) {
- printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
-
- for (i = 0; i < LZO_CMP_PAGES; i++)
- free_page((unsigned long)page[i]);
-
- return -ENOMEM;
+ data = vmalloc(sizeof(*data) * nr_threads);
+ if (!data) {
+ printk(KERN_ERR "PM: Failed to allocate LZO data\n");
+ error = -ENOMEM;
+ goto out_clean;
+ }
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct dec_data, go));
+
+ /*
+ * Start the decompression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_decompress_threadfn,
+ &data[thr],
+ "image_decompress/%zu", thr);
+ if (IS_ERR(data[thr].thr)) {
+ nr_threads = thr;
+ printk(KERN_ERR
+ "PM: Cannot start decompression threads\n");
+ error = -ENOMEM;
+ goto out_clean;
+ }
}

- cmp = vmalloc(LZO_CMP_SIZE);
- if (!cmp) {
- printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
-
- vfree(unc);
- for (i = 0; i < LZO_CMP_PAGES; i++)
- free_page((unsigned long)page[i]);
-
- return -ENOMEM;
+ for (i = 0; i < LZO_READ_PAGES; i++) {
+ page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (!page[i]) {
+ if (i < LZO_CMP_PAGES) {
+ ring_size = i;
+ printk(KERN_ERR
+ "PM: Failed to allocate LZO pages\n");
+ error = -ENOMEM;
+ goto out_clean;
+ } else {
+ break;
+ }
+ }
}
+ want = ring_size = i;

printk(KERN_INFO
+ "PM: Using %zu thread(s) for decompression.\n"
"PM: Loading and decompressing image data (%u pages) ... ",
- nr_to_read);
+ nr_threads, nr_to_read);
m = nr_to_read / 100;
if (!m)
m = 1;
@@ -808,61 +1043,128 @@ static int load_image_lzo(struct swap_map_handle *handle,
if (error <= 0)
goto out_finish;

- for (;;) {
- error = swap_read_page(handle, page[0], NULL); /* sync */
- if (error)
- break;
-
- cmp_len = *(size_t *)page[0];
- if (unlikely(!cmp_len ||
- cmp_len > lzo1x_worst_compress(LZO_UNC_SIZE))) {
- printk(KERN_ERR "PM: Invalid LZO compressed length\n");
- error = -1;
- break;
+ for(;;) {
+ for (i = 0; !eof && i < want; i++) {
+ error = swap_read_page(handle, page[ring], &bio);
+ if (error) {
+ /*
+ * On real read error, finish. On end of data,
+ * set EOF flag and just exit the read loop.
+ */
+ if (handle->cur &&
+ handle->cur->entries[handle->k]) {
+ goto out_finish;
+ } else {
+ eof = 1;
+ break;
+ }
+ }
+ if (++ring >= ring_size)
+ ring = 0;
}
+ asked += i;
+ want -= i;

- for (off = PAGE_SIZE, i = 1;
- off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
- error = swap_read_page(handle, page[i], &bio);
+ /*
+ * We are out of data, wait for some more.
+ */
+ if (!have) {
+ if (!asked)
+ break;
+
+ error = hib_wait_on_bio_chain(&bio);
if (error)
goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
}

- error = hib_wait_on_bio_chain(&bio); /* need all data now */
- if (error)
- goto out_finish;
+ for (thr = 0; have && thr < nr_threads; thr++) {
+ data[thr].cmp_len = *(size_t *)page[pg];
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(LZO_UNC_SIZE))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO compressed length\n");
+ error = -1;
+ goto out_finish;
+ }

- for (off = 0, i = 0;
- off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
- memcpy(cmp + off, page[i], PAGE_SIZE);
- }
+ need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
+ PAGE_SIZE);
+ if (need > have) {
+ if (eof > 1) {
+ error = -1;
+ goto out_finish;
+ }
+ break;
+ }

- unc_len = LZO_UNC_SIZE;
- error = lzo1x_decompress_safe(cmp + LZO_HEADER, cmp_len,
- unc, &unc_len);
- if (error < 0) {
- printk(KERN_ERR "PM: LZO decompression failed\n");
- break;
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(data[thr].cmp + off,
+ page[pg], PAGE_SIZE);
+ have--;
+ want++;
+ if (++pg >= ring_size)
+ pg = 0;
+ }
+
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
}

- if (unlikely(!unc_len ||
- unc_len > LZO_UNC_SIZE ||
- unc_len & (PAGE_SIZE - 1))) {
- printk(KERN_ERR "PM: Invalid LZO uncompressed length\n");
- error = -1;
- break;
+ /*
+ * Wait for more data while we are decompressing.
+ */
+ if (have < LZO_CMP_PAGES && asked) {
+ error = hib_wait_on_bio_chain(&bio);
+ if (error)
+ goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
}

- for (off = 0; off < unc_len; off += PAGE_SIZE) {
- memcpy(data_of(*snapshot), unc + off, PAGE_SIZE);
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);

- if (!(nr_pages % m))
- printk("\b\b\b\b%3d%%", nr_pages / m);
- nr_pages++;
+ error = data[thr].ret;

- error = snapshot_write_next(snapshot);
- if (error <= 0)
+ if (error < 0) {
+ printk(KERN_ERR
+ "PM: LZO decompression failed\n");
goto out_finish;
+ }
+
+ if (unlikely(!data[thr].unc_len ||
+ data[thr].unc_len > LZO_UNC_SIZE ||
+ data[thr].unc_len & (PAGE_SIZE - 1))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO uncompressed length\n");
+ error = -1;
+ goto out_finish;
+ }
+
+ for (off = 0;
+ off < data[thr].unc_len; off += PAGE_SIZE) {
+ memcpy(data_of(*snapshot),
+ data[thr].unc + off, PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ printk("\b\b\b\b%3d%%", nr_pages / m);
+ nr_pages++;
+
+ error = snapshot_write_next(snapshot);
+ if (error <= 0)
+ goto out_finish;
+ }
}
}

@@ -876,11 +1178,17 @@ out_finish:
} else
printk("\n");
swsusp_show_speed(&start, &stop, nr_to_read, "Read");
-
- vfree(cmp);
- vfree(unc);
- for (i = 0; i < LZO_CMP_PAGES; i++)
+out_clean:
+ for (i = 0; i < ring_size; i++)
free_page((unsigned long)page[i]);
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++) {
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ }
+ vfree(data);
+ }
+ if (page) vfree(page);

return error;
}
----------------------------------

--
Bojan