PM / Hibernate: Separate block_io

Move block I/O operations to a separate file. It is because it will
be used later not only by the swap writer.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index 43191815f874e855aa50ba34216c66ecea43a859..524e058dcf060b4f1acb845a71206082ad80f1a3 100644 (file)
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -8,7 +8,8 @@ obj-$(CONFIG_PM_SLEEP)          += console.o
 obj-$(CONFIG_FREEZER)          += process.o
 obj-$(CONFIG_SUSPEND)          += suspend.o
 obj-$(CONFIG_PM_TEST_SUSPEND)  += suspend_test.o
-obj-$(CONFIG_HIBERNATION)      += hibernate.o snapshot.o swap.o user.o
+obj-$(CONFIG_HIBERNATION)      += hibernate.o snapshot.o swap.o user.o \
+                                  block_io.o
 obj-$(CONFIG_HIBERNATION_NVS)  += hibernate_nvs.o
 
 obj-$(CONFIG_MAGIC_SYSRQ)      += poweroff.o

diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c
new file mode 100644 (file)
index 0000000..2a2f8ae
--- /dev/null
+++ b/kernel/power/block_io.c
@@ -0,0 +1,103 @@
+/*
+ * This file provides functions for block I/O operations on swap/file.
+ *
+ * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/bio.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/swap.h>
+
+#include "power.h"
+
+/**
+ *     submit - submit BIO request.
+ *     @rw:    READ or WRITE.
+ *     @off    physical offset of page.
+ *     @page:  page we're reading or writing.
+ *     @bio_chain: list of pending biod (for async reading)
+ *
+ *     Straight from the textbook - allocate and initialize the bio.
+ *     If we're reading, make sure the page is marked as dirty.
+ *     Then submit it and, if @bio_chain == NULL, wait.
+ */
+static int submit(int rw, struct block_device *bdev, sector_t sector,
+               struct page *page, struct bio **bio_chain)
+{
+       const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
+       struct bio *bio;
+
+       bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
+       bio->bi_sector = sector;
+       bio->bi_bdev = bdev;
+       bio->bi_end_io = end_swap_bio_read;
+
+       if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+               printk(KERN_ERR "PM: Adding page to bio failed at %ld\n",
+                       sector);
+               bio_put(bio);
+               return -EFAULT;
+       }
+
+       lock_page(page);
+       bio_get(bio);
+
+       if (bio_chain == NULL) {
+               submit_bio(bio_rw, bio);
+               wait_on_page_locked(page);
+               if (rw == READ)
+                       bio_set_pages_dirty(bio);
+               bio_put(bio);
+       } else {
+               if (rw == READ)
+                       get_page(page); /* These pages are freed later */
+               bio->bi_private = *bio_chain;
+               *bio_chain = bio;
+               submit_bio(bio_rw, bio);
+       }
+       return 0;
+}
+
+int hib_bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+       return submit(READ, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                       virt_to_page(addr), bio_chain);
+}
+
+int hib_bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+       return submit(WRITE, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                       virt_to_page(addr), bio_chain);
+}
+
+int hib_wait_on_bio_chain(struct bio **bio_chain)
+{
+       struct bio *bio;
+       struct bio *next_bio;
+       int ret = 0;
+
+       if (bio_chain == NULL)
+               return 0;
+
+       bio = *bio_chain;
+       if (bio == NULL)
+               return 0;
+       while (bio) {
+               struct page *page;
+
+               next_bio = bio->bi_private;
+               page = bio->bi_io_vec[0].bv_page;
+               wait_on_page_locked(page);
+               if (!PageUptodate(page) || PageError(page))
+                       ret = -EIO;
+               put_page(page);
+               bio_put(bio);
+               bio = next_bio;
+       }
+       *bio_chain = NULL;
+       return ret;
+}

diff --git a/kernel/power/power.h b/kernel/power/power.h
index b1e207dde1c251632a1118eefe36f14dfa3c9a86..006270fe382d7f756e02082e4f5309258b1ca5e3 100644 (file)
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -142,6 +142,15 @@ extern int swsusp_read(unsigned int *flags_p);
 extern int swsusp_write(unsigned int flags);
 extern void swsusp_close(fmode_t);
 
+/* kernel/power/block_io.c */
+extern struct block_device *hib_resume_bdev;
+
+extern int hib_bio_read_page(pgoff_t page_off, void *addr,
+               struct bio **bio_chain);
+extern int hib_bio_write_page(pgoff_t page_off, void *addr,
+               struct bio **bio_chain);
+extern int hib_wait_on_bio_chain(struct bio **bio_chain);
+
 struct timeval;
 /* kernel/power/swsusp.c */
 extern void swsusp_show_speed(struct timeval *, struct timeval *,

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 7f2a17e4067b4caa8d83ccf489313a29cc5fb04f..1b1ab6fcf38657d8ee1a2e11557b1a17d893f33b 100644 (file)
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -145,93 +145,7 @@ int swsusp_swap_in_use(void)
  */
 
 static unsigned short root_swap = 0xffff;
-static struct block_device *resume_bdev;
-
-/**
- *     submit - submit BIO request.
- *     @rw:    READ or WRITE.
- *     @off    physical offset of page.
- *     @page:  page we're reading or writing.
- *     @bio_chain: list of pending biod (for async reading)
- *
- *     Straight from the textbook - allocate and initialize the bio.
- *     If we're reading, make sure the page is marked as dirty.
- *     Then submit it and, if @bio_chain == NULL, wait.
- */
-static int submit(int rw, pgoff_t page_off, struct page *page,
-                       struct bio **bio_chain)
-{
-       const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
-       struct bio *bio;
-
-       bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
-       bio->bi_sector = page_off * (PAGE_SIZE >> 9);
-       bio->bi_bdev = resume_bdev;
-       bio->bi_end_io = end_swap_bio_read;
-
-       if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
-               printk(KERN_ERR "PM: Adding page to bio failed at %ld\n",
-                       page_off);
-               bio_put(bio);
-               return -EFAULT;
-       }
-
-       lock_page(page);
-       bio_get(bio);
-
-       if (bio_chain == NULL) {
-               submit_bio(bio_rw, bio);
-               wait_on_page_locked(page);
-               if (rw == READ)
-                       bio_set_pages_dirty(bio);
-               bio_put(bio);
-       } else {
-               if (rw == READ)
-                       get_page(page); /* These pages are freed later */
-               bio->bi_private = *bio_chain;
-               *bio_chain = bio;
-               submit_bio(bio_rw, bio);
-       }
-       return 0;
-}
-
-static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-       return submit(READ, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-       return submit(WRITE, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int wait_on_bio_chain(struct bio **bio_chain)
-{
-       struct bio *bio;
-       struct bio *next_bio;
-       int ret = 0;
-
-       if (bio_chain == NULL)
-               return 0;
-
-       bio = *bio_chain;
-       if (bio == NULL)
-               return 0;
-       while (bio) {
-               struct page *page;
-
-               next_bio = bio->bi_private;
-               page = bio->bi_io_vec[0].bv_page;
-               wait_on_page_locked(page);
-               if (!PageUptodate(page) || PageError(page))
-                       ret = -EIO;
-               put_page(page);
-               bio_put(bio);
-               bio = next_bio;
-       }
-       *bio_chain = NULL;
-       return ret;
-}
+struct block_device *hib_resume_bdev;
 
 /*
  * Saving part
@@ -241,14 +155,14 @@ static int mark_swapfiles(sector_t start, unsigned int flags)
 {
        int error;
 
-       bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+       hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
        if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
            !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
                memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
                memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
                swsusp_header->image = start;
                swsusp_header->flags = flags;
-               error = bio_write_page(swsusp_resume_block,
+               error = hib_bio_write_page(swsusp_resume_block,
                                        swsusp_header, NULL);
        } else {
                printk(KERN_ERR "PM: Swap header not found!\n");
@@ -267,18 +181,18 @@ static int swsusp_swap_check(void) /* This is called before saving image */
        int res;
 
        res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
-                       &resume_bdev);
+                       &hib_resume_bdev);
        if (res < 0)
                return res;
 
        root_swap = res;
-       res = blkdev_get(resume_bdev, FMODE_WRITE);
+       res = blkdev_get(hib_resume_bdev, FMODE_WRITE);
        if (res)
                return res;
 
-       res = set_blocksize(resume_bdev, PAGE_SIZE);
+       res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
        if (res < 0)
-               blkdev_put(resume_bdev, FMODE_WRITE);
+               blkdev_put(hib_resume_bdev, FMODE_WRITE);
 
        return res;
 }
@@ -309,7 +223,7 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
        } else {
                src = buf;
        }
-       return bio_write_page(offset, src, bio_chain);
+       return hib_bio_write_page(offset, src, bio_chain);
 }
 
 /*
@@ -380,7 +294,7 @@ 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 = wait_on_bio_chain(bio_chain);
+               error = hib_wait_on_bio_chain(bio_chain);
                if (error)
                        goto out;
                offset = alloc_swapdev_block(root_swap);
@@ -441,7 +355,7 @@ static int save_image(struct swap_map_handle *handle,
                        printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
                nr_pages++;
        }
-       err2 = wait_on_bio_chain(&bio);
+       err2 = hib_wait_on_bio_chain(&bio);
        do_gettimeofday(&stop);
        if (!ret)
                ret = err2;
@@ -553,7 +467,7 @@ static int get_swap_reader(struct swap_map_handle *handle, sector_t start)
        if (!handle->cur)
                return -ENOMEM;
 
-       error = bio_read_page(start, handle->cur, NULL);
+       error = hib_bio_read_page(start, handle->cur, NULL);
        if (error) {
                release_swap_reader(handle);
                return error;
@@ -573,17 +487,17 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
        offset = handle->cur->entries[handle->k];
        if (!offset)
                return -EFAULT;
-       error = bio_read_page(offset, buf, bio_chain);
+       error = hib_bio_read_page(offset, buf, bio_chain);
        if (error)
                return error;
        if (++handle->k >= MAP_PAGE_ENTRIES) {
-               error = wait_on_bio_chain(bio_chain);
+               error = hib_wait_on_bio_chain(bio_chain);
                handle->k = 0;
                offset = handle->cur->next_swap;
                if (!offset)
                        release_swap_reader(handle);
                else if (!error)
-                       error = bio_read_page(offset, handle->cur, NULL);
+                       error = hib_bio_read_page(offset, handle->cur, NULL);
        }
        return error;
 }
@@ -622,14 +536,14 @@ static int load_image(struct swap_map_handle *handle,
                if (error)
                        break;
                if (snapshot->sync_read)
-                       error = wait_on_bio_chain(&bio);
+                       error = hib_wait_on_bio_chain(&bio);
                if (error)
                        break;
                if (!(nr_pages % m))
                        printk("\b\b\b\b%3d%%", nr_pages / m);
                nr_pages++;
        }
-       err2 = wait_on_bio_chain(&bio);
+       err2 = hib_wait_on_bio_chain(&bio);
        do_gettimeofday(&stop);
        if (!error)
                error = err2;
@@ -686,11 +600,11 @@ int swsusp_check(void)
 {
        int error;
 
-       resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
-       if (!IS_ERR(resume_bdev)) {
-               set_blocksize(resume_bdev, PAGE_SIZE);
+       hib_resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
+       if (!IS_ERR(hib_resume_bdev)) {
+               set_blocksize(hib_resume_bdev, PAGE_SIZE);
                memset(swsusp_header, 0, PAGE_SIZE);
-               error = bio_read_page(swsusp_resume_block,
+               error = hib_bio_read_page(swsusp_resume_block,
                                        swsusp_header, NULL);
                if (error)
                        goto put;
@@ -698,7 +612,7 @@ int swsusp_check(void)
                if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
                        memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
                        /* Reset swap signature now */
-                       error = bio_write_page(swsusp_resume_block,
+                       error = hib_bio_write_page(swsusp_resume_block,
                                                swsusp_header, NULL);
                } else {
                        error = -EINVAL;
@@ -706,11 +620,11 @@ int swsusp_check(void)
 
 put:
                if (error)
-                       blkdev_put(resume_bdev, FMODE_READ);
+                       blkdev_put(hib_resume_bdev, FMODE_READ);
                else
                        pr_debug("PM: Signature found, resuming\n");
        } else {
-               error = PTR_ERR(resume_bdev);
+               error = PTR_ERR(hib_resume_bdev);
        }
 
        if (error)
@@ -725,12 +639,12 @@ put:
 
 void swsusp_close(fmode_t mode)
 {
-       if (IS_ERR(resume_bdev)) {
+       if (IS_ERR(hib_resume_bdev)) {
                pr_debug("PM: Image device not initialised\n");
                return;
        }
 
-       blkdev_put(resume_bdev, mode);
+       blkdev_put(hib_resume_bdev, mode);
 }
 
 static int swsusp_header_init(void)