> -----Original Message----- > From: David Sterba [mailto:dsterba@xxxxxxx] > Sent: Monday, July 16, 2018 8:34 PM > To: Gu, Jinxiang/顾 金香 <gujx@xxxxxxxxxxxxxx> > Cc: linux-btrfs@xxxxxxxxxxxxxxx; anand.jain@xxxxxxxxxx > Subject: Re: [PATCH v5 2/2] btrfs: get device pointer from btrfs_scan_one_device > > On Mon, Jul 16, 2018 at 05:11:17PM +0800, Gu Jinxiang wrote: > > Instead of pointer to btrfs_fs_devices as an arg in > > btrfs_scan_one_device, better to make it as a return value. > > > > And since btrfs_fs_devices can be get by btrfs_device, > > better to return btrfs_device than fs_btrfs_devices. > > > > Signed-off-by: Gu Jinxiang <gujx@xxxxxxxxxxxxxx> > > --- > > > > Changelog: > > v5: rebase to misc-next. > > v4: as suggested by Anand, change return value of > > btrfs_scan_one_device from btrfs_fs_devices to btrfs_device. > > v3: as comment by robot, use PTR_ERR_OR_ZERO, and rebase to misc-next. > > v2: as comment by Nikolay, use ERR_CAST instead of cast type manually. > > > > fs/btrfs/super.c | 35 ++++++++++++++++++++++------------- > > fs/btrfs/volumes.c | 22 ++++++++-------------- > > fs/btrfs/volumes.h | 4 ++-- > > 3 files changed, 32 insertions(+), 29 deletions(-) > > > > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > > index dcab4a0244e5..413bbe2d6db2 100644 > > --- a/fs/btrfs/super.c > > +++ b/fs/btrfs/super.c > > @@ -888,7 +888,7 @@ static int btrfs_parse_early_options(const char *options, fmode_t flags, > > { > > substring_t args[MAX_OPT_ARGS]; > > char *device_name, *opts, *orig, *p; > > - struct btrfs_fs_devices *fs_devices = NULL; > > + struct btrfs_device *device = NULL; > > int error = 0; > > > > lockdep_assert_held(&uuid_mutex); > > @@ -918,11 +918,13 @@ static int btrfs_parse_early_options(const char *options, fmode_t flags, > > error = -ENOMEM; > > goto out; > > } > > - error = btrfs_scan_one_device(device_name, flags, > > - holder, &fs_devices); > > + device = btrfs_scan_one_device(device_name, flags, > > + holder); > > kfree(device_name); > > - if (error) > > + if (IS_ERR(device)) { > > + error = PTR_ERR(device); > > goto out; > > + } > > } > > } > > > > @@ -1518,6 +1520,7 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, > > { > > struct block_device *bdev = NULL; > > struct super_block *s; > > + struct btrfs_device *device = NULL; > > struct btrfs_fs_devices *fs_devices = NULL; > > struct btrfs_fs_info *fs_info = NULL; > > struct security_mnt_opts new_sec_opts; > > @@ -1561,12 +1564,15 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, > > goto error_fs_info; > > } > > > > - error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices); > > - if (error) { > > + device = btrfs_scan_one_device(device_name, mode, fs_type); > > + if (IS_ERR(device)) { > > + error = PTR_ERR(device); > > mutex_unlock(&uuid_mutex); > > goto error_fs_info; > > } > > > > + fs_devices = device->fs_devices; > > + > > fs_info->fs_devices = fs_devices; > > > > error = btrfs_open_devices(fs_devices, mode, fs_type); > > @@ -2227,7 +2233,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, > > unsigned long arg) > > { > > struct btrfs_ioctl_vol_args *vol; > > - struct btrfs_fs_devices *fs_devices; > > + struct btrfs_device *device = NULL; > > int ret = -ENOTTY; > > > > if (!capable(CAP_SYS_ADMIN)) > > @@ -2240,19 +2246,22 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, > > switch (cmd) { > > case BTRFS_IOC_SCAN_DEV: > > mutex_lock(&uuid_mutex); > > - ret = btrfs_scan_one_device(vol->name, FMODE_READ, > > - &btrfs_root_fs_type, &fs_devices); > > + device = btrfs_scan_one_device(vol->name, FMODE_READ, > > + &btrfs_root_fs_type); > > + ret = PTR_ERR_OR_ZERO(device); > > mutex_unlock(&uuid_mutex); > > break; > > case BTRFS_IOC_DEVICES_READY: > > mutex_lock(&uuid_mutex); > > - ret = btrfs_scan_one_device(vol->name, FMODE_READ, > > - &btrfs_root_fs_type, &fs_devices); > > - if (ret) { > > + device = btrfs_scan_one_device(vol->name, FMODE_READ, > > + &btrfs_root_fs_type); > > + if (IS_ERR(device)) { > > + ret = PTR_ERR(device); > > mutex_unlock(&uuid_mutex); > > break; > > } > > - ret = !(fs_devices->num_devices == fs_devices->total_devices); > > + ret = !(device->fs_devices->num_devices == > > + device->fs_devices->total_devices); > > mutex_unlock(&uuid_mutex); > > break; > > case BTRFS_IOC_GET_SUPPORTED_FEATURES: > > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > > index 88d37bfa99c8..9f485696461b 100644 > > --- a/fs/btrfs/volumes.c > > +++ b/fs/btrfs/volumes.c > > @@ -1213,15 +1213,14 @@ static int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr, > > * and we are not allowed to call set_blocksize during the scan. The superblock > > * is read via pagecache > > */ > > -int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, > > - struct btrfs_fs_devices **fs_devices_ret) > > +struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags, > > + void *holder) > > { > > struct btrfs_super_block *disk_super; > > bool new_device_added = false; > > - struct btrfs_device *device; > > + struct btrfs_device *ret = NULL; > > struct block_device *bdev; > > struct page *page; > > - int ret = 0; > > u64 bytenr; > > > > lockdep_assert_held(&uuid_mutex); > > @@ -1237,21 +1236,16 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, > > > > bdev = blkdev_get_by_path(path, flags, holder); > > if (IS_ERR(bdev)) > > - return PTR_ERR(bdev); > > + return ERR_CAST(bdev); > > > > if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) { > > - ret = -EINVAL; > > + ret = ERR_PTR(-EINVAL); > > goto error_bdev_put; > > } > > > > - device = device_list_add(path, disk_super, &new_device_added); > > - if (IS_ERR(device)) { > > - ret = PTR_ERR(device); > > - } else { > > - *fs_devices_ret = device->fs_devices; > > - if (new_device_added) > > - btrfs_free_stale_devices(path, device); > > - } > > + ret = device_list_add(path, disk_super, &new_device_added); > > + if (new_device_added) > > + btrfs_free_stale_devices(path, ret); > > Why is this skipping the error handling? I've resolved the conflict in a > different way in misc-next, have you had a look there? Since when new_device_added set to be true, the return value of device_list_add must not a error value. So, I think no necessary to add the judge. > > Also the 'ret' got dropped and 'device' is used instead, the non-int > type for ret would be confusing. OK, Thank you. > > > > > btrfs_release_disk_super(page); > > > > diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h > > index 9665b84b1026..06d8bb7dd557 100644 > > --- a/fs/btrfs/volumes.h > > +++ b/fs/btrfs/volumes.h > > @@ -403,8 +403,8 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio, > > int mirror_num, int async_submit); > > int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, > > fmode_t flags, void *holder); > > -int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, > > - struct btrfs_fs_devices **fs_devices_ret); > > +struct btrfs_device *btrfs_scan_one_device(const char *path, > > + fmode_t flags, void *holder); > > int btrfs_close_devices(struct btrfs_fs_devices *fs_devices); > > void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step); > > void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info, > > -- > > 2.17.1 > > > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > ?韬{.n?????%??檩??w?{.n???{饼?~镶?^n?■???h?璀?｛?夸z罐?+€?zf＂?????i?????_璁?:+v??撸?
