X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=kernel%2Fpower%2Fswap.c;fp=kernel%2Fpower%2Fswap.c;h=0917c5db5ecbc301ae302582bc28ae8623d37655;hb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;hp=044b8e0c102547fe909e1d25142dad3c311ad4f8;hpb=4e76c8a9fa413ccc09d3f7f664183dcce3555d57;p=linux-2.6.git diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 044b8e0c1..0917c5db5 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -49,18 +50,16 @@ static int mark_swapfiles(swp_entry_t start) { int error; - rw_swap_page_sync(READ, - swp_entry(root_swap, 0), - virt_to_page((unsigned long)&swsusp_header)); + rw_swap_page_sync(READ, swp_entry(root_swap, 0), + virt_to_page((unsigned long)&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; - error = rw_swap_page_sync(WRITE, - swp_entry(root_swap, 0), - virt_to_page((unsigned long) - &swsusp_header)); + error = rw_swap_page_sync(WRITE, swp_entry(root_swap, 0), + virt_to_page((unsigned long)&swsusp_header), + NULL); } else { pr_debug("swsusp: Partition is not swap space.\n"); error = -ENODEV; @@ -88,16 +87,37 @@ static int swsusp_swap_check(void) /* This is called before saving image */ * write_page - Write one page to given swap location. * @buf: Address we're writing. * @offset: Offset of the swap page we're writing to. + * @bio_chain: Link the next write BIO here */ -static int write_page(void *buf, unsigned long offset) +static int write_page(void *buf, unsigned long offset, struct bio **bio_chain) { swp_entry_t entry; int error = -ENOSPC; if (offset) { + struct page *page = virt_to_page(buf); + + if (bio_chain) { + /* + * Whether or not we successfully allocated a copy page, + * we take a ref on the page here. It gets undone in + * wait_on_bio_chain(). + */ + struct page *page_copy; + page_copy = alloc_page(GFP_ATOMIC); + if (page_copy == NULL) { + WARN_ON_ONCE(1); + bio_chain = NULL; /* Go synchronous */ + get_page(page); + } else { + memcpy(page_address(page_copy), + page_address(page), PAGE_SIZE); + page = page_copy; + } + } entry = swp_entry(root_swap, offset); - error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf)); + error = rw_swap_page_sync(WRITE, entry, page, bio_chain); } return error; } @@ -146,6 +166,26 @@ static void release_swap_writer(struct swap_map_handle *handle) handle->bitmap = NULL; } +static void show_speed(struct timeval *start, struct timeval *stop, + unsigned nr_pages, char *msg) +{ + s64 elapsed_centisecs64; + int centisecs; + int k; + int kps; + + elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start); + do_div(elapsed_centisecs64, NSEC_PER_SEC / 100); + centisecs = elapsed_centisecs64; + if (centisecs == 0) + centisecs = 1; /* avoid div-by-zero */ + k = nr_pages * (PAGE_SIZE / 1024); + kps = (k * 100) / centisecs; + printk("%s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n", msg, k, + centisecs / 100, centisecs % 100, + kps / 1000, (kps % 1000) / 10); +} + static int get_swap_writer(struct swap_map_handle *handle) { handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); @@ -165,37 +205,70 @@ static int get_swap_writer(struct swap_map_handle *handle) return 0; } -static int swap_write_page(struct swap_map_handle *handle, void *buf) +static int wait_on_bio_chain(struct bio **bio_chain) { - int error; + 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; +} + +static int swap_write_page(struct swap_map_handle *handle, void *buf, + struct bio **bio_chain) +{ + int error = 0; unsigned long offset; if (!handle->cur) return -EINVAL; offset = alloc_swap_page(root_swap, handle->bitmap); - error = write_page(buf, offset); + error = write_page(buf, offset, bio_chain); if (error) return error; handle->cur->entries[handle->k++] = offset; if (handle->k >= MAP_PAGE_ENTRIES) { + error = wait_on_bio_chain(bio_chain); + if (error) + goto out; offset = alloc_swap_page(root_swap, handle->bitmap); if (!offset) return -ENOSPC; handle->cur->next_swap = offset; - error = write_page(handle->cur, handle->cur_swap); + error = write_page(handle->cur, handle->cur_swap, NULL); if (error) - return error; + goto out; memset(handle->cur, 0, PAGE_SIZE); handle->cur_swap = offset; handle->k = 0; } - return 0; +out: + return error; } static int flush_swap_writer(struct swap_map_handle *handle) { if (handle->cur && handle->cur_swap) - return write_page(handle->cur, handle->cur_swap); + return write_page(handle->cur, handle->cur_swap, NULL); else return -EINVAL; } @@ -206,21 +279,29 @@ static int flush_swap_writer(struct swap_map_handle *handle) static int save_image(struct swap_map_handle *handle, struct snapshot_handle *snapshot, - unsigned int nr_pages) + unsigned int nr_to_write) { unsigned int m; int ret; int error = 0; + int nr_pages; + int err2; + struct bio *bio; + struct timeval start; + struct timeval stop; - printk("Saving image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; + printk("Saving image data pages (%u pages) ... ", nr_to_write); + m = nr_to_write / 100; if (!m) m = 1; nr_pages = 0; + bio = NULL; + do_gettimeofday(&start); do { ret = snapshot_read_next(snapshot, PAGE_SIZE); if (ret > 0) { - error = swap_write_page(handle, data_of(*snapshot)); + error = swap_write_page(handle, data_of(*snapshot), + &bio); if (error) break; if (!(nr_pages % m)) @@ -228,8 +309,13 @@ static int save_image(struct swap_map_handle *handle, nr_pages++; } } while (ret > 0); + err2 = wait_on_bio_chain(&bio); + do_gettimeofday(&stop); + if (!error) + error = err2; if (!error) printk("\b\b\b\bdone\n"); + show_speed(&start, &stop, nr_to_write, "Wrote"); return error; } @@ -263,11 +349,11 @@ int swsusp_write(void) struct swap_map_handle handle; struct snapshot_handle snapshot; struct swsusp_info *header; - unsigned long start; int error; if ((error = swsusp_swap_check())) { - printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n"); + printk(KERN_ERR "swsusp: Cannot find swap device, try " + "swapon -a.\n"); return error; } memset(&snapshot, 0, sizeof(struct snapshot_handle)); @@ -281,16 +367,17 @@ int swsusp_write(void) } error = get_swap_writer(&handle); if (!error) { - start = handle.cur_swap; - error = swap_write_page(&handle, header); - } - if (!error) - error = save_image(&handle, &snapshot, header->pages - 1); - if (!error) { - flush_swap_writer(&handle); - printk("S"); - error = mark_swapfiles(swp_entry(root_swap, start)); - printk("|\n"); + unsigned long start = handle.cur_swap; + error = swap_write_page(&handle, header, NULL); + if (!error) + error = save_image(&handle, &snapshot, + header->pages - 1); + if (!error) { + flush_swap_writer(&handle); + printk("S"); + error = mark_swapfiles(swp_entry(root_swap, start)); + printk("|\n"); + } } if (error) free_all_swap_pages(root_swap, handle.bitmap); @@ -298,25 +385,6 @@ int swsusp_write(void) return error; } -/* - * Using bio to read from swap. - * This code requires a bit more work than just using buffer heads - * but, it is the recommended way for 2.5/2.6. - * The following are to signal the beginning and end of I/O. Bios - * finish asynchronously, while we want them to happen synchronously. - * A simple atomic_t, and a wait loop take care of this problem. - */ - -static atomic_t io_done = ATOMIC_INIT(0); - -static int end_io(struct bio *bio, unsigned int num, int err) -{ - if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) - panic("I/O error reading memory image"); - atomic_set(&io_done, 0); - return 0; -} - static struct block_device *resume_bdev; /** @@ -324,15 +392,15 @@ static struct block_device *resume_bdev; * @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 writing, make sure the page is marked as dirty. - * Then submit it and wait. + * 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, void *page) +static int submit(int rw, pgoff_t page_off, struct page *page, + struct bio **bio_chain) { - int error = 0; struct bio *bio; bio = bio_alloc(GFP_ATOMIC, 1); @@ -340,33 +408,40 @@ static int submit(int rw, pgoff_t page_off, void *page) return -ENOMEM; bio->bi_sector = page_off * (PAGE_SIZE >> 9); bio->bi_bdev = resume_bdev; - bio->bi_end_io = end_io; + bio->bi_end_io = end_swap_bio_read; - if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { - printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); - error = -EFAULT; - goto Done; + if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { + printk("swsusp: ERROR: adding page to bio at %ld\n", page_off); + bio_put(bio); + return -EFAULT; } - atomic_set(&io_done, 1); - submit_bio(rw | (1 << BIO_RW_SYNC), bio); - while (atomic_read(&io_done)) - yield(); - if (rw == READ) - bio_set_pages_dirty(bio); - Done: - bio_put(bio); - return error; + lock_page(page); + bio_get(bio); + + if (bio_chain == NULL) { + submit_bio(rw | (1 << BIO_RW_SYNC), bio); + wait_on_page_locked(page); + if (rw == READ) + bio_set_pages_dirty(bio); + bio_put(bio); + } else { + get_page(page); + bio->bi_private = *bio_chain; + *bio_chain = bio; + submit_bio(rw, bio); + } + return 0; } -static int bio_read_page(pgoff_t page_off, void *page) +static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain) { - return submit(READ, page_off, page); + return submit(READ, page_off, virt_to_page(addr), bio_chain); } -static int bio_write_page(pgoff_t page_off, void *page) +static int bio_write_page(pgoff_t page_off, void *addr) { - return submit(WRITE, page_off, page); + return submit(WRITE, page_off, virt_to_page(addr), NULL); } /** @@ -391,7 +466,7 @@ static int get_swap_reader(struct swap_map_handle *handle, handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); if (!handle->cur) return -ENOMEM; - error = bio_read_page(swp_offset(start), handle->cur); + error = bio_read_page(swp_offset(start), handle->cur, NULL); if (error) { release_swap_reader(handle); return error; @@ -400,7 +475,8 @@ static int get_swap_reader(struct swap_map_handle *handle, return 0; } -static int swap_read_page(struct swap_map_handle *handle, void *buf) +static int swap_read_page(struct swap_map_handle *handle, void *buf, + struct bio **bio_chain) { unsigned long offset; int error; @@ -410,16 +486,17 @@ 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); + error = bio_read_page(offset, buf, bio_chain); if (error) return error; if (++handle->k >= MAP_PAGE_ENTRIES) { + error = wait_on_bio_chain(bio_chain); handle->k = 0; offset = handle->cur->next_swap; if (!offset) release_swap_reader(handle); - else - error = bio_read_page(offset, handle->cur); + else if (!error) + error = bio_read_page(offset, handle->cur, NULL); } return error; } @@ -432,33 +509,48 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf) static int load_image(struct swap_map_handle *handle, struct snapshot_handle *snapshot, - unsigned int nr_pages) + unsigned int nr_to_read) { unsigned int m; - int ret; int error = 0; + struct timeval start; + struct timeval stop; + struct bio *bio; + int err2; + unsigned nr_pages; - printk("Loading image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; + printk("Loading image data pages (%u pages) ... ", nr_to_read); + m = nr_to_read / 100; if (!m) m = 1; nr_pages = 0; - do { - ret = snapshot_write_next(snapshot, PAGE_SIZE); - if (ret > 0) { - error = swap_read_page(handle, data_of(*snapshot)); - if (error) - break; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } - } while (ret > 0); + bio = NULL; + do_gettimeofday(&start); + for ( ; ; ) { + error = snapshot_write_next(snapshot, PAGE_SIZE); + if (error <= 0) + break; + error = swap_read_page(handle, data_of(*snapshot), &bio); + if (error) + break; + if (snapshot->sync_read) + error = 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); + do_gettimeofday(&stop); + if (!error) + error = err2; if (!error) { printk("\b\b\b\bdone\n"); if (!snapshot_image_loaded(snapshot)) error = -ENODATA; } + show_speed(&start, &stop, nr_to_read, "Read"); return error; } @@ -481,7 +573,7 @@ int swsusp_read(void) header = (struct swsusp_info *)data_of(snapshot); error = get_swap_reader(&handle, swsusp_header.image); if (!error) - error = swap_read_page(&handle, header); + error = swap_read_page(&handle, header, NULL); if (!error) error = load_image(&handle, &snapshot, header->pages - 1); release_swap_reader(&handle); @@ -507,7 +599,7 @@ int swsusp_check(void) if (!IS_ERR(resume_bdev)) { set_blocksize(resume_bdev, PAGE_SIZE); memset(&swsusp_header, 0, sizeof(swsusp_header)); - if ((error = bio_read_page(0, &swsusp_header))) + if ((error = bio_read_page(0, &swsusp_header, NULL))) return error; if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);