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authorRobert Morris <[email protected]>2014-08-04 13:06:48 -0400
committerRobert Morris <[email protected]>2014-08-04 13:06:48 -0400
commit2c56547272e43b483d560a61692f1e24926a82fb (patch)
tree514014c69ff9cfe2a67159b9a3f514a3a619aea6 /log.c
parent020c8e2384877ffc13579f633ac3c723f80baf8c (diff)
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every iput() and namei() must be inside a transaction
Diffstat (limited to 'log.c')
-rw-r--r--log.c6
1 files changed, 1 insertions, 5 deletions
diff --git a/log.c b/log.c
index 1814edc..95cc4d5 100644
--- a/log.c
+++ b/log.c
@@ -5,7 +5,7 @@
#include "fs.h"
#include "buf.h"
-// Simple logging. Each system call that might write the file system
+// Simple logging. Each file system system call
// should be surrounded with begin_trans() and commit_trans() calls.
//
// The log holds at most one transaction at a time. Commit forces
@@ -18,10 +18,6 @@
// one transaction reading a block that another one has modified,
// for example an i-node block.
//
-// Read-only system calls don't need to use transactions, though
-// this means that they may observe uncommitted data. I-node and
-// buffer locks prevent read-only calls from seeing inconsistent data.
-//
// The log is a physical re-do log containing disk blocks.
// The on-disk log format:
// header block, containing sector #s for block A, B, C, ...