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[92.109.99.123]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a993fdd2202sm153215766b.55.2024.10.06.01.24.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 06 Oct 2024 01:24:02 -0700 (PDT) From: Amir Goldstein To: Miklos Szeredi , Al Viro Cc: Christian Brauner , linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org Subject: [PATCH v2 0/4] Stash overlay real upper file in backing_file Date: Sun, 6 Oct 2024 10:23:55 +0200 Message-Id: <20241006082359.263755-1-amir73il@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Hi all, This is v2 of the code to avoid temporary backing file opens in overlayfs, taking into account Al's comments on v1 [1]. Miklos, The implementation of ovl_real_file_path() helper is roughly based on ovl_real_dir_file(). do you see any problems with this approach or any races not handled? Note that I did have a logical bug in v1 (always choosing the stashed upperfile if it exists), so there may be more. Thanks, Amir. Changes since v1: - Use helpers ovl_real_file() and ovl_upper_file() to express that ovl_real_file() cannot return NULL - Fix readability and bug is code to select and store stashed upperfile [1] https://lore.kernel.org/linux-fsdevel/20241004102342.179434-1-amir73il@gmail.com/ Amir Goldstein (4): ovl: do not open non-data lower file for fsync ovl: stash upper real file in backing_file struct ovl: convert ovl_real_fdget_path() callers to ovl_real_file_path() ovl: convert ovl_real_fdget() callers to ovl_real_file() fs/file_table.c | 7 ++ fs/internal.h | 6 + fs/overlayfs/file.c | 288 ++++++++++++++++++++++++++------------------ 3 files changed, 182 insertions(+), 119 deletions(-)