From: Dietmar Maurer <dietmar@proxmox.com>
To: pbs-devel@lists.proxmox.com
Subject: [pbs-devel] [PATCH proxmox-backup v3 2/4] tape: lock media_catalog file to to get a consistent view with load_catalog
Date: Wed, 28 Jul 2021 11:11:16 +0200 [thread overview]
Message-ID: <20210728091118.581161-3-dietmar@proxmox.com> (raw)
In-Reply-To: <20210728091118.581161-1-dietmar@proxmox.com>
---
src/tape/media_catalog.rs | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/src/tape/media_catalog.rs b/src/tape/media_catalog.rs
index 62c6acb3..1bd136f9 100644
--- a/src/tape/media_catalog.rs
+++ b/src/tape/media_catalog.rs
@@ -231,7 +231,12 @@ impl MediaCatalog {
pending: Vec::new(),
};
- let (found_magic_number, _) = me.load_catalog(&mut file, media_id.media_set_label.as_ref())?;
+ // Note: lock file, to get a consistent view with load_catalog
+ nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::LockExclusive)?;
+ let result = me.load_catalog(&mut file, media_id.media_set_label.as_ref());
+ nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::Unlock)?;
+
+ let (found_magic_number, _) = result?;
if !found_magic_number {
me.pending.extend(&Self::PROXMOX_BACKUP_MEDIA_CATALOG_MAGIC_1_1);
@@ -372,9 +377,18 @@ impl MediaCatalog {
match self.file {
Some(ref mut file) => {
- file.write_all(&self.pending)?;
- file.flush()?;
- file.sync_data()?;
+ let pending = &self.pending;
+ // Note: lock file, to get a consistent view with load_catalog
+ nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::LockExclusive)?;
+ let result: Result<(), Error> = proxmox::try_block!({
+ file.write_all(pending)?;
+ file.flush()?;
+ file.sync_data()?;
+ Ok(())
+ });
+ nix::fcntl::flock(file.as_raw_fd(), nix::fcntl::FlockArg::Unlock)?;
+
+ result?;
}
None => bail!("media catalog not writable (opened read only)"),
}
--
2.30.2
next prev parent reply other threads:[~2021-07-28 9:11 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-28 9:11 [pbs-devel] [PATCH proxmox-backup v3 0/4] improve catalog handling Dietmar Maurer
2021-07-28 9:11 ` [pbs-devel] [PATCH proxmox-backup v3 1/4] cleanup: factor out tape catalog path helpers Dietmar Maurer
2021-07-28 9:11 ` Dietmar Maurer [this message]
2021-07-28 9:11 ` [pbs-devel] [PATCH proxmox-backup v3 3/4] tape: media_catalog: add snapshot list cache for catalog Dietmar Maurer
2021-07-28 9:11 ` [pbs-devel] [PATCH proxmox-backup v3 4/4] api2: tape: media: use MediaCatalog::snapshot_list for content listing Dietmar Maurer
2021-07-29 12:30 ` [pbs-devel] applied: [PATCH proxmox-backup v3 0/4] improve catalog handling Dietmar Maurer
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