From: Namjae Jeon Subject: [PATCH v10 1/12] fs: Add support FALLOC_FL_INSERT_RANGE for fallocate Date: Sun, 22 Feb 2015 00:45:43 +0900 Message-ID: <1424533554-28024-2-git-send-email-linkinjeon@gmail.com> References: <1424533554-28024-1-git-send-email-linkinjeon@gmail.com> Cc: linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xfs-VZNHf3L845pBDgjK7y7TUQ@public.gmane.org, a.sangwan-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, bfoster-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Namjae Jeon , Namjae Jeon To: david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org, tytso-3s7WtUTddSA@public.gmane.org Return-path: In-Reply-To: <1424533554-28024-1-git-send-email-linkinjeon-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org From: Namjae Jeon FALLOC_FL_INSERT_RANGE command is the opposite command of FALLOC_FL_COLLAPSE_RANGE that is needed for advertisers or someone who want to add some data in the middle of file. FALLOC_FL_INSERT_RANGE will create space for writing new data within a file after shifting extents to right as given length. and this command also has same limitation as FALLOC_FL_COLLAPSE_RANGE, that is block boundary and use ftruncate(2) for crosses EOF. Signed-off-by: Namjae Jeon Signed-off-by: Ashish Sangwan --- fs/open.c | 8 ++++++-- include/linux/falloc.h | 6 ++++++ include/uapi/linux/falloc.h | 17 +++++++++++++++++ 3 files changed, 29 insertions(+), 2 deletions(-) diff --git a/fs/open.c b/fs/open.c index 33f9cbf..b724cc0 100644 --- a/fs/open.c +++ b/fs/open.c @@ -231,8 +231,7 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) return -EINVAL; /* Return error if mode is not supported */ - if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | - FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)) + if (mode & ~FALLOC_FL_SUPPORTED_MASK) return -EOPNOTSUPP; /* Punch hole and zero range are mutually exclusive */ @@ -250,6 +249,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) (mode & ~FALLOC_FL_COLLAPSE_RANGE)) return -EINVAL; + /* Insert range should only be used exclusively. */ + if ((mode & FALLOC_FL_INSERT_RANGE) && + (mode & ~FALLOC_FL_INSERT_RANGE)) + return -EINVAL; + if (!(file->f_mode & FMODE_WRITE)) return -EBADF; diff --git a/include/linux/falloc.h b/include/linux/falloc.h index 3159168..9961110 100644 --- a/include/linux/falloc.h +++ b/include/linux/falloc.h @@ -21,4 +21,10 @@ struct space_resv { #define FS_IOC_RESVSP _IOW('X', 40, struct space_resv) #define FS_IOC_RESVSP64 _IOW('X', 42, struct space_resv) +#define FALLOC_FL_SUPPORTED_MASK (FALLOC_FL_KEEP_SIZE | \ + FALLOC_FL_PUNCH_HOLE | \ + FALLOC_FL_COLLAPSE_RANGE | \ + FALLOC_FL_ZERO_RANGE | \ + FALLOC_FL_INSERT_RANGE) + #endif /* _FALLOC_H_ */ diff --git a/include/uapi/linux/falloc.h b/include/uapi/linux/falloc.h index d1197ae..3e445a7 100644 --- a/include/uapi/linux/falloc.h +++ b/include/uapi/linux/falloc.h @@ -41,4 +41,21 @@ */ #define FALLOC_FL_ZERO_RANGE 0x10 +/* + * FALLOC_FL_INSERT_RANGE is use to insert space within the file size without + * overwriting any existing data. The contents of the file beyond offset are + * shifted towards right by len bytes to create a hole. As such, this + * operation will increase the size of the file by len bytes. + * + * Different filesystems may implement different limitations on the granularity + * of the operation. Most will limit operations to filesystem block size + * boundaries, but this boundary may be larger or smaller depending on + * the filesystem and/or the configuration of the filesystem or file. + * + * Attempting to insert space using this flag at OR beyond the end of + * the file is considered an illegal operation - just use ftruncate(2) or + * fallocate(2) with mode 0 for such type of operations. + */ +#define FALLOC_FL_INSERT_RANGE 0x20 + #endif /* _UAPI_FALLOC_H_ */ -- 1.7.9.5