From: Yu Kuai <yukuai3@xxxxxxxxxx> On the one hand covert to use folio while reading bdev inode, on the other hand prevent to access bd_inode directly. Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> --- drivers/mtd/devices/block2mtd.c | 81 +++++++++++++++------------------ 1 file changed, 36 insertions(+), 45 deletions(-) diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c index aa44a23ec045..cf201bf73184 100644 --- a/drivers/mtd/devices/block2mtd.c +++ b/drivers/mtd/devices/block2mtd.c @@ -46,40 +46,34 @@ struct block2mtd_dev { /* Static info about the MTD, used in cleanup_module */ static LIST_HEAD(blkmtd_device_list); - -static struct page *page_read(struct address_space *mapping, pgoff_t index) -{ - return read_mapping_page(mapping, index, NULL); -} - /* erase a specified part of the device */ static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len) { - struct address_space *mapping = - dev->bdev_handle->bdev->bd_inode->i_mapping; - struct page *page; + struct block_device *bdev = dev->bdev_handle->bdev; + struct folio *folio; pgoff_t index = to >> PAGE_SHIFT; // page index int pages = len >> PAGE_SHIFT; u_long *p; u_long *max; while (pages) { - page = page_read(mapping, index); - if (IS_ERR(page)) - return PTR_ERR(page); + folio = bdev_read_folio(bdev, index << PAGE_SHIFT); + if (IS_ERR(folio)) + return PTR_ERR(folio); - max = page_address(page) + PAGE_SIZE; - for (p=page_address(page); p<max; p++) + max = folio_address(folio) + folio_size(folio); + for (p = folio_address(folio); p < max; p++) if (*p != -1UL) { - lock_page(page); - memset(page_address(page), 0xff, PAGE_SIZE); - set_page_dirty(page); - unlock_page(page); - balance_dirty_pages_ratelimited(mapping); + folio_lock(folio); + memset(folio_address(folio), 0xff, + folio_size(folio)); + folio_mark_dirty(folio); + folio_unlock(folio); + bdev_balance_dirty_pages_ratelimited(bdev); break; } - put_page(page); + folio_put(folio); pages--; index++; } @@ -106,9 +100,7 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) { struct block2mtd_dev *dev = mtd->priv; - struct address_space *mapping = - dev->bdev_handle->bdev->bd_inode->i_mapping; - struct page *page; + struct folio *folio; pgoff_t index = from >> PAGE_SHIFT; int offset = from & (PAGE_SIZE-1); int cpylen; @@ -120,12 +112,13 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len, cpylen = len; // this page len = len - cpylen; - page = page_read(mapping, index); - if (IS_ERR(page)) - return PTR_ERR(page); + folio = bdev_read_folio(dev->bdev_handle->bdev, + index << PAGE_SHIFT); + if (IS_ERR(folio)) + return PTR_ERR(folio); - memcpy(buf, page_address(page) + offset, cpylen); - put_page(page); + memcpy(buf, folio_address(folio) + offset, cpylen); + folio_put(folio); if (retlen) *retlen += cpylen; @@ -141,9 +134,8 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len, static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf, loff_t to, size_t len, size_t *retlen) { - struct page *page; - struct address_space *mapping = - dev->bdev_handle->bdev->bd_inode->i_mapping; + struct block_device *bdev = dev->bdev_handle->bdev; + struct folio *folio; pgoff_t index = to >> PAGE_SHIFT; // page index int offset = to & ~PAGE_MASK; // page offset int cpylen; @@ -155,18 +147,18 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf, cpylen = len; // this page len = len - cpylen; - page = page_read(mapping, index); - if (IS_ERR(page)) - return PTR_ERR(page); + folio = bdev_read_folio(bdev, index << PAGE_SHIFT); + if (IS_ERR(folio)) + return PTR_ERR(folio); - if (memcmp(page_address(page)+offset, buf, cpylen)) { - lock_page(page); - memcpy(page_address(page) + offset, buf, cpylen); - set_page_dirty(page); - unlock_page(page); - balance_dirty_pages_ratelimited(mapping); + if (memcmp(folio_address(folio) + offset, buf, cpylen)) { + folio_lock(folio); + memcpy(folio_address(folio) + offset, buf, cpylen); + folio_mark_dirty(folio); + folio_unlock(folio); + bdev_balance_dirty_pages_ratelimited(bdev); } - put_page(page); + folio_put(folio); if (retlen) *retlen += cpylen; @@ -211,8 +203,7 @@ static void block2mtd_free_device(struct block2mtd_dev *dev) kfree(dev->mtd.name); if (dev->bdev_handle) { - invalidate_mapping_pages( - dev->bdev_handle->bdev->bd_inode->i_mapping, 0, -1); + invalidate_bdev(dev->bdev_handle->bdev); bdev_release(dev->bdev_handle); } @@ -295,7 +286,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size, goto err_free_block2mtd; } - if ((long)bdev->bd_inode->i_size % erase_size) { + if (bdev_nr_bytes(bdev) % erase_size) { pr_err("erasesize must be a divisor of device size\n"); goto err_free_block2mtd; } @@ -313,7 +304,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size, dev->mtd.name = name; - dev->mtd.size = bdev->bd_inode->i_size & PAGE_MASK; + dev->mtd.size = bdev_nr_bytes(bdev) & PAGE_MASK; dev->mtd.erasesize = erase_size; dev->mtd.writesize = 1; dev->mtd.writebufsize = PAGE_SIZE; -- 2.39.2