| Message ID | 1309120615-18104-3-git-send-email-hugo@carfax.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hugo Mills wrote: > This patch adds an ioctl for cancelling a btrfs balance operation > mid-flight. The ioctl simply sets a flag, and the operation terminates > after the current block group move has completed. > > Signed-off-by: Hugo Mills <hugo@carfax.org.uk> > --- > fs/btrfs/ctree.h | 1 + > fs/btrfs/ioctl.c | 28 ++++++++++++++++++++++++++++ > fs/btrfs/ioctl.h | 1 + > fs/btrfs/volumes.c | 7 ++++++- > 4 files changed, 36 insertions(+), 1 deletions(-) > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 25aa3cf..5031085 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -876,6 +876,7 @@ struct btrfs_block_group_cache { > struct btrfs_balance_info { > u32 expected; > u32 completed; > + int cancel_pending; > }; > > struct reloc_control; > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index 5ddf816..d4458d0 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -2868,6 +2868,32 @@ error: > return ret; > } > > +/* > + * Cancel a running balance operation > + */ > +long btrfs_ioctl_balance_cancel(struct btrfs_fs_info *fs_info) > +{ > + int err = 0; > + > + if (!capable(CAP_SYS_ADMIN)) > + return -EPERM; > + > + spin_lock(&fs_info->balance_info_lock); > + if (!fs_info->balance_info) { > + err = -EINVAL; > + goto error; > + } > + if (fs_info->balance_info->cancel_pending) { > + err = -ECANCELED; > + goto error; > + } > + fs_info->balance_info->cancel_pending = 1; > + > +error: > + spin_unlock(&fs_info->balance_info_lock); > + return err; > +} > + > long btrfs_ioctl(struct file *file, unsigned int > cmd, unsigned long arg) > { > @@ -2915,6 +2941,8 @@ long btrfs_ioctl(struct file *file, unsigned int > return btrfs_balance(root->fs_info->dev_root); > case BTRFS_IOC_BALANCE_PROGRESS: > return btrfs_ioctl_balance_progress(root->fs_info, argp); > + case BTRFS_IOC_BALANCE_CANCEL: > + return btrfs_ioctl_balance_cancel(root->fs_info); > case BTRFS_IOC_CLONE: > return btrfs_ioctl_clone(file, arg, 0, 0, 0); > case BTRFS_IOC_CLONE_RANGE: > diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h > index 575b25f..edcbe61 100644 > --- a/fs/btrfs/ioctl.h > +++ b/fs/btrfs/ioctl.h > @@ -255,4 +255,5 @@ struct btrfs_ioctl_balance_progress { > struct btrfs_ioctl_fs_info_args) > #define BTRFS_IOC_BALANCE_PROGRESS _IOR(BTRFS_IOCTL_MAGIC, 32, \ > struct btrfs_ioctl_balance_progress) > +#define BTRFS_IOC_BALANCE_CANCEL _IO(BTRFS_IOCTL_MAGIC, 33) > #endif > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index 4c0a386..f38b231 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -2049,6 +2049,7 @@ int btrfs_balance(struct btrfs_root *dev_root) > bal_info->expected = -1; /* One less than actually counted, > because chunk 0 is special */ > bal_info->completed = 0; > + bal_info->cancel_pending = 0; > spin_unlock(&dev_root->fs_info->balance_info_lock); > > /* step one make some room on all the devices */ > @@ -2109,7 +2110,7 @@ int btrfs_balance(struct btrfs_root *dev_root) > key.offset = (u64)-1; > key.type = BTRFS_CHUNK_ITEM_KEY; > > - while (1) { > + while (!bal_info->cancel_pending) { > ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); > if (ret < 0) > goto error; > @@ -2149,6 +2150,10 @@ int btrfs_balance(struct btrfs_root *dev_root) > bal_info->completed, bal_info->expected); > } > ret = 0; > + if (bal_info->cancel_pending) { > + printk(KERN_INFO "btrfs: balance cancelled\n"); > + ret = -EINTR; > + } Why not detect if there's any pending signal in the while loop? so we can just use Ctrl+C to cancel balance. > error: > btrfs_free_path(path); > spin_lock(&dev_root->fs_info->balance_info_lock); -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Jun 29, 2011 at 02:00:20PM +0800, Li Zefan wrote: > Hugo Mills wrote: > > @@ -2149,6 +2150,10 @@ int btrfs_balance(struct btrfs_root *dev_root) > > bal_info->completed, bal_info->expected); > > } > > ret = 0; > > + if (bal_info->cancel_pending) { > > + printk(KERN_INFO "btrfs: balance cancelled\n"); > > + ret = -EINTR; > > + } > > Why not detect if there's any pending signal in the while loop? so > we can just use Ctrl+C to cancel balance. Balance is capable of running in background, you could not send the Ctrl-C to such process. david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 25aa3cf..5031085 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -876,6 +876,7 @@ struct btrfs_block_group_cache { struct btrfs_balance_info { u32 expected; u32 completed; + int cancel_pending; }; struct reloc_control; diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 5ddf816..d4458d0 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2868,6 +2868,32 @@ error: return ret; } +/* + * Cancel a running balance operation + */ +long btrfs_ioctl_balance_cancel(struct btrfs_fs_info *fs_info) +{ + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + spin_lock(&fs_info->balance_info_lock); + if (!fs_info->balance_info) { + err = -EINVAL; + goto error; + } + if (fs_info->balance_info->cancel_pending) { + err = -ECANCELED; + goto error; + } + fs_info->balance_info->cancel_pending = 1; + +error: + spin_unlock(&fs_info->balance_info_lock); + return err; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2915,6 +2941,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_balance(root->fs_info->dev_root); case BTRFS_IOC_BALANCE_PROGRESS: return btrfs_ioctl_balance_progress(root->fs_info, argp); + case BTRFS_IOC_BALANCE_CANCEL: + return btrfs_ioctl_balance_cancel(root->fs_info); case BTRFS_IOC_CLONE: return btrfs_ioctl_clone(file, arg, 0, 0, 0); case BTRFS_IOC_CLONE_RANGE: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 575b25f..edcbe61 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -255,4 +255,5 @@ struct btrfs_ioctl_balance_progress { struct btrfs_ioctl_fs_info_args) #define BTRFS_IOC_BALANCE_PROGRESS _IOR(BTRFS_IOCTL_MAGIC, 32, \ struct btrfs_ioctl_balance_progress) +#define BTRFS_IOC_BALANCE_CANCEL _IO(BTRFS_IOCTL_MAGIC, 33) #endif diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 4c0a386..f38b231 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2049,6 +2049,7 @@ int btrfs_balance(struct btrfs_root *dev_root) bal_info->expected = -1; /* One less than actually counted, because chunk 0 is special */ bal_info->completed = 0; + bal_info->cancel_pending = 0; spin_unlock(&dev_root->fs_info->balance_info_lock); /* step one make some room on all the devices */ @@ -2109,7 +2110,7 @@ int btrfs_balance(struct btrfs_root *dev_root) key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; - while (1) { + while (!bal_info->cancel_pending) { ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) goto error; @@ -2149,6 +2150,10 @@ int btrfs_balance(struct btrfs_root *dev_root) bal_info->completed, bal_info->expected); } ret = 0; + if (bal_info->cancel_pending) { + printk(KERN_INFO "btrfs: balance cancelled\n"); + ret = -EINTR; + } error: btrfs_free_path(path); spin_lock(&dev_root->fs_info->balance_info_lock);
This patch adds an ioctl for cancelling a btrfs balance operation mid-flight. The ioctl simply sets a flag, and the operation terminates after the current block group move has completed. Signed-off-by: Hugo Mills <hugo@carfax.org.uk> --- fs/btrfs/ctree.h | 1 + fs/btrfs/ioctl.c | 28 ++++++++++++++++++++++++++++ fs/btrfs/ioctl.h | 1 + fs/btrfs/volumes.c | 7 ++++++- 4 files changed, 36 insertions(+), 1 deletions(-)