dovecot: Fixed cache file's NFS attribute cache flushing.

[dovecot at dovecot.org]

details:   http://hg.dovecot.org/dovecot/rev/c991d1b132d8
changeset: 6815:c991d1b132d8
user:      Timo Sirainen <tss at iki.fi>
date:      Fri Nov 16 04:45:53 2007 +0200
description:
Fixed cache file's NFS attribute cache flushing.

diffstat:

2 files changed, 25 insertions(+), 11 deletions(-)
src/lib-index/mail-cache-private.h |    3 +++
src/lib-index/mail-cache.c         |   33 ++++++++++++++++++++++-----------

diffs (78 lines):

diff -r 020838158024 -r c991d1b132d8 src/lib-index/mail-cache-private.h
--- a/src/lib-index/mail-cache-private.h	Fri Nov 16 04:25:12 2007 +0200
+++ b/src/lib-index/mail-cache-private.h	Fri Nov 16 04:45:53 2007 +0200
@@ -131,6 +131,9 @@ struct mail_cache {
 	char *filepath;
 	int fd;
 
+	ino_t st_ino;
+	dev_t st_dev;
+
 	void *mmap_base;
 	const void *data;
 	size_t mmap_length;
diff -r 020838158024 -r c991d1b132d8 src/lib-index/mail-cache.c
--- a/src/lib-index/mail-cache.c	Fri Nov 16 04:25:12 2007 +0200
+++ b/src/lib-index/mail-cache.c	Fri Nov 16 04:45:53 2007 +0200
@@ -86,15 +86,18 @@ static void mail_cache_init_file_cache(s
 
 	file_cache_set_fd(cache->file_cache, cache->fd);
 
-	if (fstat(cache->fd, &st) < 0)
+	if (fstat(cache->fd, &st) == 0)
+		file_cache_set_size(cache->file_cache, st.st_size);
+	else if (errno != ESTALE)
 		mail_cache_set_syscall_error(cache, "fstat()");
-	else
-		file_cache_set_size(cache->file_cache, st.st_size);
+
+	cache->st_ino = st.st_ino;
+	cache->st_dev = st.st_dev;
 }
 
 static bool mail_cache_need_reopen(struct mail_cache *cache)
 {
-	struct stat st1, st2;
+	struct stat st;
 
 	if (MAIL_CACHE_IS_UNUSABLE(cache)) {
 		if (cache->need_compress_file_seq != 0) {
@@ -111,16 +114,22 @@ static bool mail_cache_need_reopen(struc
 		return TRUE;
 
 	/* see if the file has changed */
-	if (fstat(cache->fd, &st1) < 0) {
-		mail_cache_set_syscall_error(cache, "fstat()");
-		return TRUE;
-	}
-	if (stat(cache->filepath, &st2) < 0) {
+	if (cache->index->nfs_flush)
+		nfs_flush_attr_cache(cache->filepath, TRUE);
+	if (nfs_safe_stat(cache->filepath, &st) < 0) {
 		mail_cache_set_syscall_error(cache, "stat()");
 		return TRUE;
 	}
-	return st1.st_ino != st2.st_ino ||
-		!CMP_DEV_T(st1.st_dev, st2.st_dev);
+	if (cache->index->nfs_flush) {
+		/* if the old file has been deleted, the new file may have
+		   the same inode as the old one, but we'll catch this by
+		   flushing attribute cache and seeing if it fails with
+		   ESTALE */
+		if (!nfs_flush_attr_cache_fd(cache->filepath, cache->fd))
+			return TRUE;
+	}
+	return st.st_ino != cache->st_ino ||
+		!CMP_DEV_T(st.st_dev, cache->st_dev);
 }
 
 int mail_cache_reopen(struct mail_cache *cache)
@@ -481,6 +490,8 @@ static int mail_cache_lock_file(struct m
 	if (ret <= 0)
 		return ret;
 
+	if (cache->index->nfs_flush)
+		nfs_flush_attr_cache_fd(cache->filepath, cache->fd);
 	mail_cache_flush_read_cache(cache, TRUE);
 	return 1;
 }