mm/swap: Convert to use bdev_open_by_dev()

Convert swapping code to use bdev_open_by_dev() and pass the handle
around.

CC: linux-mm@kvack.org
CC: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-18-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 493487ed7c388b31bf8a9bef37fea86c365e33a2..f6dd6575b90545c3c927efbb033c1134e091b69a 100644 (file)
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -298,6 +298,7 @@ struct swap_info_struct {
        unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */
        struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
        struct rb_root swap_extent_root;/* root of the swap extent rbtree */
+       struct bdev_handle *bdev_handle;/* open handle of the bdev */
        struct block_device *bdev;      /* swap device or bdev of swap file */
        struct file *swap_file;         /* seldom referenced */
        unsigned int old_block_size;    /* seldom referenced */

diff --git a/mm/swapfile.c b/mm/swapfile.c
index e52f486834ebf79e31c21f00845969050d256d38..4bc70f459164147e260eeb3b669737b0df1a2b82 100644 (file)
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2530,11 +2530,10 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
        exit_swap_address_space(p->type);
 
        inode = mapping->host;
-       if (S_ISBLK(inode->i_mode)) {
-               struct block_device *bdev = I_BDEV(inode);
-
-               set_blocksize(bdev, old_block_size);
-               blkdev_put(bdev, p);
+       if (p->bdev_handle) {
+               set_blocksize(p->bdev, old_block_size);
+               bdev_release(p->bdev_handle);
+               p->bdev_handle = NULL;
        }
 
        inode_lock(inode);
@@ -2764,13 +2763,14 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
        int error;
 
        if (S_ISBLK(inode->i_mode)) {
-               p->bdev = blkdev_get_by_dev(inode->i_rdev,
+               p->bdev_handle = bdev_open_by_dev(inode->i_rdev,
                                BLK_OPEN_READ | BLK_OPEN_WRITE, p, NULL);
-               if (IS_ERR(p->bdev)) {
-                       error = PTR_ERR(p->bdev);
-                       p->bdev = NULL;
+               if (IS_ERR(p->bdev_handle)) {
+                       error = PTR_ERR(p->bdev_handle);
+                       p->bdev_handle = NULL;
                        return error;
                }
+               p->bdev = p->bdev_handle->bdev;
                p->old_block_size = block_size(p->bdev);
                error = set_blocksize(p->bdev, PAGE_SIZE);
                if (error < 0)
@@ -3206,9 +3206,10 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
        p->percpu_cluster = NULL;
        free_percpu(p->cluster_next_cpu);
        p->cluster_next_cpu = NULL;
-       if (inode && S_ISBLK(inode->i_mode) && p->bdev) {
+       if (p->bdev_handle) {
                set_blocksize(p->bdev, p->old_block_size);
-               blkdev_put(p->bdev, p);
+               bdev_release(p->bdev_handle);
+               p->bdev_handle = NULL;
        }
        inode = NULL;
        destroy_swap_extents(p);