From bb3247a399801ebba20bef101c89e563f5fe7f02 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 21 Sep 2020 09:19:55 +0200 Subject: PM: rewrite is_hibernate_resume_dev to not require an inode Just check the dev_t to help simplifying the code. Signed-off-by: Christoph Hellwig Acked-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Jens Axboe --- kernel/power/user.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'kernel/power') diff --git a/kernel/power/user.c b/kernel/power/user.c index d5eedc2baa2a..b5815685b944 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -35,12 +35,12 @@ static struct snapshot_data { bool ready; bool platform_support; bool free_bitmaps; - struct inode *bd_inode; + dev_t dev; } snapshot_state; -int is_hibernate_resume_dev(const struct inode *bd_inode) +int is_hibernate_resume_dev(dev_t dev) { - return hibernation_available() && snapshot_state.bd_inode == bd_inode; + return hibernation_available() && snapshot_state.dev == dev; } static int snapshot_open(struct inode *inode, struct file *filp) @@ -101,7 +101,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) data->frozen = false; data->ready = false; data->platform_support = false; - data->bd_inode = NULL; + data->dev = 0; Unlock: unlock_system_sleep(); @@ -117,7 +117,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) swsusp_free(); data = filp->private_data; - data->bd_inode = NULL; + data->dev = 0; free_all_swap_pages(data->swap); if (data->frozen) { pm_restore_gfp_mask(); @@ -245,7 +245,7 @@ static int snapshot_set_swap_area(struct snapshot_data *data, if (data->swap < 0) return -ENODEV; - data->bd_inode = bdev->bd_inode; + data->dev = bdev->bd_dev; bdput(bdev); return 0; } -- cgit v1.2.3-58-ga151 From 21bd900572f3708e281ea25f051fc92462eb1193 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 21 Sep 2020 09:19:56 +0200 Subject: mm: split swap_type_of swap_type_of is used for two entirely different purposes: (1) check what swap type a given device/offset corresponds to (2) find the first available swap device that can be written to Mixing both in a single function creates an unreadable mess. Create two separate functions instead, and switch both to pass a dev_t instead of a struct block_device to further simplify the code. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- include/linux/swap.h | 3 ++- kernel/power/swap.c | 17 ++++++++--------- kernel/power/user.c | 16 ++++------------ mm/swapfile.c | 39 +++++++++++++++++++++------------------ 4 files changed, 35 insertions(+), 40 deletions(-) (limited to 'kernel/power') diff --git a/include/linux/swap.h b/include/linux/swap.h index 661046994db4..4340a7b6e7a1 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -467,7 +467,8 @@ extern int swapcache_prepare(swp_entry_t); extern void swap_free(swp_entry_t); extern void swapcache_free_entries(swp_entry_t *entries, int n); extern int free_swap_and_cache(swp_entry_t); -extern int swap_type_of(dev_t, sector_t, struct block_device **); +int swap_type_of(dev_t device, sector_t offset); +int find_first_swap(dev_t *device); extern unsigned int count_swap_pages(int, int); extern sector_t map_swap_page(struct page *, struct block_device **); extern sector_t swapdev_block(int, pgoff_t); diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 01e2858b5fe3..9d3ffbfe08db 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -335,12 +335,17 @@ static int swsusp_swap_check(void) { int res; - res = swap_type_of(swsusp_resume_device, swsusp_resume_block, - &hib_resume_bdev); + if (swsusp_resume_device) + res = swap_type_of(swsusp_resume_device, swsusp_resume_block); + else + res = find_first_swap(&swsusp_resume_device); if (res < 0) return res; - root_swap = res; + + hib_resume_bdev = bdget(swsusp_resume_device); + if (!hib_resume_bdev) + return -ENOMEM; res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL); if (res) return res; @@ -349,12 +354,6 @@ static int swsusp_swap_check(void) if (res < 0) blkdev_put(hib_resume_bdev, FMODE_WRITE); - /* - * Update the resume device to the one actually used, - * so the test_resume mode can use it in case it is - * invoked from hibernate() to test the snapshot. - */ - swsusp_resume_device = hib_resume_bdev->bd_dev; return res; } diff --git a/kernel/power/user.c b/kernel/power/user.c index b5815685b944..6510a8f7687f 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -69,8 +69,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) memset(&data->handle, 0, sizeof(struct snapshot_handle)); if ((filp->f_flags & O_ACCMODE) == O_RDONLY) { /* Hibernating. The image device should be accessible. */ - data->swap = swsusp_resume_device ? - swap_type_of(swsusp_resume_device, 0, NULL) : -1; + data->swap = swap_type_of(swsusp_resume_device, 0); data->mode = O_RDONLY; data->free_bitmaps = false; error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls); @@ -210,7 +209,6 @@ struct compat_resume_swap_area { static int snapshot_set_swap_area(struct snapshot_data *data, void __user *argp) { - struct block_device *bdev; sector_t offset; dev_t swdev; @@ -237,16 +235,10 @@ static int snapshot_set_swap_area(struct snapshot_data *data, * User space encodes device types as two-byte values, * so we need to recode them */ - if (!swdev) { - data->swap = -1; - return -EINVAL; - } - data->swap = swap_type_of(swdev, offset, &bdev); + data->swap = swap_type_of(swdev, offset); if (data->swap < 0) - return -ENODEV; - - data->dev = bdev->bd_dev; - bdput(bdev); + return swdev ? -ENODEV : -EINVAL; + data->dev = swdev; return 0; } diff --git a/mm/swapfile.c b/mm/swapfile.c index 7438c4affc75..b90f86920743 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1801,13 +1801,12 @@ int free_swap_and_cache(swp_entry_t entry) * * This is needed for the suspend to disk (aka swsusp). */ -int swap_type_of(dev_t device, sector_t offset, struct block_device **bdev_p) +int swap_type_of(dev_t device, sector_t offset) { - struct block_device *bdev = NULL; int type; - if (device) - bdev = bdget(device); + if (!device) + return -1; spin_lock(&swap_lock); for (type = 0; type < nr_swapfiles; type++) { @@ -1816,30 +1815,34 @@ int swap_type_of(dev_t device, sector_t offset, struct block_device **bdev_p) if (!(sis->flags & SWP_WRITEOK)) continue; - if (!bdev) { - if (bdev_p) - *bdev_p = bdgrab(sis->bdev); - - spin_unlock(&swap_lock); - return type; - } - if (bdev == sis->bdev) { + if (device == sis->bdev->bd_dev) { struct swap_extent *se = first_se(sis); if (se->start_block == offset) { - if (bdev_p) - *bdev_p = bdgrab(sis->bdev); - spin_unlock(&swap_lock); - bdput(bdev); return type; } } } spin_unlock(&swap_lock); - if (bdev) - bdput(bdev); + return -ENODEV; +} +int find_first_swap(dev_t *device) +{ + int type; + + spin_lock(&swap_lock); + for (type = 0; type < nr_swapfiles; type++) { + struct swap_info_struct *sis = swap_info[type]; + + if (!(sis->flags & SWP_WRITEOK)) + continue; + *device = sis->bdev->bd_dev; + spin_unlock(&swap_lock); + return type; + } + spin_unlock(&swap_lock); return -ENODEV; } -- cgit v1.2.3-58-ga151 From 36daaa98f7ad9224421b18549a3f7bdf4d220414 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 21 Sep 2020 09:19:57 +0200 Subject: PM: mm: cleanup swsusp_swap_check Use blkdev_get_by_dev instead of bdget + blkdev_get. Signed-off-by: Christoph Hellwig Acked-by: Rafael J. Wysocki Signed-off-by: Jens Axboe --- kernel/power/swap.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'kernel/power') diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 9d3ffbfe08db..71385bedcc3a 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -343,12 +343,10 @@ static int swsusp_swap_check(void) return res; root_swap = res; - hib_resume_bdev = bdget(swsusp_resume_device); - if (!hib_resume_bdev) - return -ENOMEM; - res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL); - if (res) - return res; + hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, FMODE_WRITE, + NULL); + if (IS_ERR(hib_resume_bdev)) + return PTR_ERR(hib_resume_bdev); res = set_blocksize(hib_resume_bdev, PAGE_SIZE); if (res < 0) -- cgit v1.2.3-58-ga151