Stop poking into block layer internals and just open the block device file an use kernel_read and kernel_write on it. Note that this means the transformation from name_to_dev_t can't be used anymore, and proper block device file names must be used.
Signed-off-by: Christoph Hellwig <[email protected]> --- fs/pstore/blk.c | 152 +++++++++++++------------------------ include/linux/pstore_blk.h | 2 + init/main.c | 4 + 3 files changed, 57 insertions(+), 101 deletions(-) diff --git a/fs/pstore/blk.c b/fs/pstore/blk.c index 0430b190a1df2a..bd4eadfc9bd795 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -8,15 +8,13 @@ #include <linux/kernel.h> #include <linux/module.h> -#include "../../block/blk.h" #include <linux/blkdev.h> #include <linux/string.h> -#include <linux/of.h> -#include <linux/of_address.h> -#include <linux/platform_device.h> #include <linux/pstore_blk.h> +#include <linux/fs.h> +#include <linux/file.h> +#include <linux/init_syscalls.h> #include <linux/mount.h> -#include <linux/uio.h> static long kmsg_size = CONFIG_PSTORE_BLK_KMSG_SIZE; module_param(kmsg_size, long, 0400); @@ -88,7 +86,6 @@ MODULE_PARM_DESC(blkdev, "block device for pstore storage"); * during the register/unregister functions. */ static DEFINE_MUTEX(pstore_blk_lock); -static struct block_device *psblk_bdev; static struct pstore_zone_info *pstore_zone_info; #define check_size(name, alignsize) ({ \ @@ -185,70 +182,20 @@ void unregister_pstore_device(const struct pstore_zone_ops *ops) } EXPORT_SYMBOL_GPL(unregister_pstore_device); +static struct file *psblk_file; + static ssize_t psblk_generic_blk_read(char *buf, size_t bytes, loff_t pos) { - struct block_device *bdev = psblk_bdev; - struct file file; - struct kiocb kiocb; - struct iov_iter iter; - struct kvec iov = {.iov_base = buf, .iov_len = bytes}; - - if (!bdev) - return -ENODEV; - - memset(&file, 0, sizeof(struct file)); - file.f_mapping = bdev->bd_inode->i_mapping; - file.f_flags = O_DSYNC | __O_SYNC | O_NOATIME; - file.f_inode = bdev->bd_inode; - file_ra_state_init(&file.f_ra, file.f_mapping); - - init_sync_kiocb(&kiocb, &file); - kiocb.ki_pos = pos; - iov_iter_kvec(&iter, READ, &iov, 1, bytes); - - return generic_file_read_iter(&kiocb, &iter); + return kernel_read(psblk_file, buf, bytes, &pos); } static ssize_t psblk_generic_blk_write(const char *buf, size_t bytes, loff_t pos) { - struct block_device *bdev = psblk_bdev; - struct iov_iter iter; - struct kiocb kiocb; - struct file file; - ssize_t ret; - struct kvec iov = {.iov_base = (void *)buf, .iov_len = bytes}; - - if (!bdev) - return -ENODEV; - /* Console/Ftrace backend may handle buffer until flush dirty zones */ if (in_interrupt() || irqs_disabled()) return -EBUSY; - - memset(&file, 0, sizeof(struct file)); - file.f_mapping = bdev->bd_inode->i_mapping; - file.f_flags = O_DSYNC | __O_SYNC | O_NOATIME; - file.f_inode = bdev->bd_inode; - - init_sync_kiocb(&kiocb, &file); - kiocb.ki_pos = pos; - iov_iter_kvec(&iter, WRITE, &iov, 1, bytes); - - inode_lock(bdev->bd_inode); - ret = generic_write_checks(&kiocb, &iter); - if (ret > 0) - ret = generic_perform_write(&file, &iter, pos); - inode_unlock(bdev->bd_inode); - - if (likely(ret > 0)) { - const struct file_operations f_op = {.fsync = blkdev_fsync}; - - file.f_op = &f_op; - kiocb.ki_pos += ret; - ret = generic_write_sync(&kiocb, ret); - } - return ret; + return kernel_write(psblk_file, buf, bytes, &pos); } static const struct pstore_zone_ops pstore_blk_zone_ops = { @@ -257,68 +204,71 @@ static const struct pstore_zone_ops pstore_blk_zone_ops = { .write = psblk_generic_blk_write, }; -static int __init pstore_blk_init(void) +static int __init __pstore_blk_init(const char *name) { - char bdev_name[BDEVNAME_SIZE]; - struct block_device *bdev; - int ret = -ENODEV; - fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL; - sector_t nr_sects; - + int ret = -EINVAL; + if (!best_effort || !blkdev[0]) return 0; - /* hold bdev exclusively */ - bdev = blkdev_get_by_path(blkdev, mode, blkdev); - if (IS_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); - } + psblk_file = filp_open(name, O_RDWR | O_DSYNC | O_NOATIME | O_EXCL, 0); + if (IS_ERR(psblk_file)) { + ret = PTR_ERR(psblk_file); + pr_err("failed to open '%s': %d!\n", name, ret); + goto out; } - - 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; + if (!S_ISBLK(file_inode(psblk_file)->i_mode)) { + pr_err("'%s' is not block device!\n", blkdev); + goto out_fput; } - /* psblk_bdev must be assigned before register to pstore/blk */ - psblk_bdev = bdev; - ret = register_pstore_device(&pstore_blk_zone_ops, - nr_sects << SECTOR_SHIFT, 0); + file_inode(psblk_file)->i_bdev->bd_inode->i_size, 0); if (ret) - goto err_put_bdev; + goto out_fput; - bdevname(bdev, bdev_name); - pr_info("attached %s (no dedicated panic_write!)\n", bdev_name); + pr_info("using device '%s'\n", blkdev); return 0; - -err_put_bdev: - blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); - psblk_bdev = NULL; +out_fput: + fput(psblk_file); +out: + psblk_file = NULL; return ret; } + +#ifdef MODULE +static int __init pstore_blk_init(void) +{ + return __pstore_blk_init(blkdev); +} late_initcall(pstore_blk_init); static void __exit pstore_blk_exit(void) { - if (!psblk_bdev) + if (!psblk_file) return; unregister_pstore_device(&pstore_blk_zone_ops); - blkdev_put(psblk_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); + fput(psblk_file); } module_exit(pstore_blk_exit); +#else /* MODULE */ +/* + * During early boot the real root file system hasn't been mounted yet, + * and not device nodes are present yet. Use the same scheme to find + * the device that we use for mounting the root file system. + */ +void __init pstore_blk_early_init(void) +{ + const char devname[] = "/dev/pstore-blk"; + dev_t dev = name_to_dev_t(blkdev); + + if (!dev) + return; + init_unlink(devname); + init_mknod(devname, S_IFBLK | 0600, new_encode_dev(dev)); + __pstore_blk_init(devname); +} +#endif /* MODULE */ /* get information of pstore/blk */ int pstore_blk_get_config(struct pstore_blk_config *info) diff --git a/include/linux/pstore_blk.h b/include/linux/pstore_blk.h index 0abd412a6cb3e3..7c06b9d6740e2a 100644 --- a/include/linux/pstore_blk.h +++ b/include/linux/pstore_blk.h @@ -39,4 +39,6 @@ struct pstore_blk_config { */ int pstore_blk_get_config(struct pstore_blk_config *info); +void __init pstore_blk_early_init(void); + #endif diff --git a/init/main.c b/init/main.c index 1af84337cb18d5..058cce64f70390 100644 --- a/init/main.c +++ b/init/main.c @@ -98,6 +98,7 @@ #include <linux/mem_encrypt.h> #include <linux/kcsan.h> #include <linux/init_syscalls.h> +#include <linux/pstore_blk.h> #include <asm/io.h> #include <asm/bugs.h> @@ -1524,6 +1525,9 @@ static noinline void __init kernel_init_freeable(void) prepare_namespace(); } + if (IS_BUILTIN(CONFIG_PSTORE_BLK)) + pstore_blk_early_init(); + /* * Ok, we have completed the initial bootup, and * we're essentially up and running. Get rid of the -- 2.28.0
