Remove the pointless psblk_get_bdev and psblk_put_bdev helper, and don't bother holding pstore_blk_lock over the block device open / close interactions given that they only happen first thing during module init and last thing during module exit. Also don't bother with unregistering a zone info that did not come from the actually block backed code, as users like mtd have to unregister it themselves already.
Signed-off-by: Christoph Hellwig <[email protected]> --- fs/pstore/blk.c | 156 ++++++++++++------------------------------------ 1 file changed, 38 insertions(+), 118 deletions(-) diff --git a/fs/pstore/blk.c b/fs/pstore/blk.c index 3a2214ecf942ae..a8aa56cba96d59 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -91,12 +91,6 @@ static DEFINE_MUTEX(pstore_blk_lock); static struct block_device *psblk_bdev; static struct pstore_zone_info *pstore_zone_info; -struct bdev_info { - dev_t devt; - sector_t nr_sects; - sector_t start_sect; -}; - #define check_size(name, alignsize) ({ \ long _##name_ = (name); \ _##name_ = _##name_ <= 0 ? 0 : (_##name_ * 1024); \ @@ -205,75 +199,6 @@ void unregister_pstore_device(struct pstore_device_info *dev) } EXPORT_SYMBOL_GPL(unregister_pstore_device); -/** - * psblk_get_bdev() - open block device - * - * @holder: Exclusive holder identifier - * @info: Information about bdev to fill in - * - * Return: pointer to block device on success and others on error. - * - * On success, the returned block_device has reference count of one. - */ -static struct block_device *psblk_get_bdev(void *holder, - struct bdev_info *info) -{ - struct block_device *bdev = ERR_PTR(-ENODEV); - fmode_t mode = FMODE_READ | FMODE_WRITE; - sector_t nr_sects; - - lockdep_assert_held(&pstore_blk_lock); - - if (pstore_zone_info) - return ERR_PTR(-EBUSY); - - if (!blkdev[0]) - return ERR_PTR(-ENODEV); - - if (holder) - mode |= FMODE_EXCL; - bdev = blkdev_get_by_path(blkdev, mode, holder); - if (IS_ERR(bdev)) { - dev_t devt; - - devt = name_to_dev_t(blkdev); - if (devt == 0) - return ERR_PTR(-ENODEV); - bdev = blkdev_get_by_dev(devt, mode, holder); - if (IS_ERR(bdev)) - return bdev; - } - - nr_sects = part_nr_sects_read(bdev->bd_part); - if (!nr_sects) { - pr_err("not enough space for '%s'\n", blkdev); - blkdev_put(bdev, mode); - return ERR_PTR(-ENOSPC); - } - - if (info) { - info->devt = bdev->bd_dev; - info->nr_sects = nr_sects; - info->start_sect = get_start_sect(bdev); - } - - return bdev; -} - -static void psblk_put_bdev(struct block_device *bdev, void *holder) -{ - fmode_t mode = FMODE_READ | FMODE_WRITE; - - lockdep_assert_held(&pstore_blk_lock); - - if (!bdev) - return; - - if (holder) - mode |= FMODE_EXCL; - blkdev_put(bdev, mode); -} - static ssize_t psblk_generic_blk_read(char *buf, size_t bytes, loff_t pos) { struct block_device *bdev = psblk_bdev; @@ -340,29 +265,39 @@ static ssize_t psblk_generic_blk_write(const char *buf, size_t bytes, return ret; } -static int __register_pstore_blk(void) +static int __init pstore_blk_init(void) { char bdev_name[BDEVNAME_SIZE]; struct block_device *bdev; struct pstore_device_info dev; - struct bdev_info binfo; - void *holder = blkdev; int ret = -ENODEV; - - lockdep_assert_held(&pstore_blk_lock); + fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL; + sector_t nr_sects; + + if (!best_effort || !blkdev[0]) + return 0; /* hold bdev exclusively */ - memset(&binfo, 0, sizeof(binfo)); - bdev = psblk_get_bdev(holder, &binfo); + bdev = blkdev_get_by_path(blkdev, mode, blkdev); if (IS_ERR(bdev)) { - pr_err("failed to open '%s'!\n", blkdev); - return PTR_ERR(bdev); + dev_t devt; + + devt = name_to_dev_t(blkdev); + if (devt == 0) { + pr_err("failed to open '%s'!\n", blkdev); + return -ENODEV; + } + bdev = blkdev_get_by_dev(devt, mode, blkdev); + if (IS_ERR(bdev)) { + pr_err("failed to open '%s'!\n", blkdev); + return PTR_ERR(bdev); + } } - /* only allow driver matching the @blkdev */ - if (!binfo.devt) { - pr_debug("no major\n"); - ret = -ENODEV; + nr_sects = part_nr_sects_read(bdev->bd_part); + if (!nr_sects) { + pr_err("not enough space for '%s'\n", blkdev); + ret = -ENOSPC; goto err_put_bdev; } @@ -370,11 +305,11 @@ static int __register_pstore_blk(void) psblk_bdev = bdev; memset(&dev, 0, sizeof(dev)); - dev.total_size = binfo.nr_sects << SECTOR_SHIFT; + dev.total_size = nr_sects << SECTOR_SHIFT; dev.read = psblk_generic_blk_read; dev.write = psblk_generic_blk_write; - ret = __register_pstore_device(&dev); + ret = register_pstore_device(&dev); if (ret) goto err_put_bdev; @@ -383,10 +318,22 @@ static int __register_pstore_blk(void) return 0; err_put_bdev: + blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); psblk_bdev = NULL; - psblk_put_bdev(bdev, holder); return ret; } +late_initcall(pstore_blk_init); + +static void __exit pstore_blk_exit(void) +{ + struct pstore_device_info dev = { .read = psblk_generic_blk_read }; + + if (!psblk_bdev) + return; + unregister_pstore_device(&dev); + blkdev_put(psblk_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); +} +module_exit(pstore_blk_exit); /* get information of pstore/blk */ int pstore_blk_get_config(struct pstore_blk_config *info) @@ -402,33 +349,6 @@ int pstore_blk_get_config(struct pstore_blk_config *info) } EXPORT_SYMBOL_GPL(pstore_blk_get_config); -static int __init pstore_blk_init(void) -{ - int ret = 0; - - mutex_lock(&pstore_blk_lock); - if (!pstore_zone_info && best_effort && blkdev[0]) - ret = __register_pstore_blk(); - mutex_unlock(&pstore_blk_lock); - - return ret; -} -late_initcall(pstore_blk_init); - -static void __exit pstore_blk_exit(void) -{ - struct pstore_device_info dev = { }; - - mutex_lock(&pstore_blk_lock); - if (pstore_zone_info) - dev.read = pstore_zone_info->read; - __unregister_pstore_device(&dev); - if (psblk_bdev) - psblk_put_bdev(psblk_bdev, blkdev); - mutex_unlock(&pstore_blk_lock); -} -module_exit(pstore_blk_exit); - MODULE_LICENSE("GPL"); MODULE_AUTHOR("WeiXiong Liao <[email protected]>"); MODULE_AUTHOR("Kees Cook <[email protected]>"); -- 2.28.0
