[OE-core] [PATCH 2/6] e2fsprogs: let debugfs do sparse copy
Darren Hart
dvhart at linux.intel.com
Thu Aug 22 14:52:33 UTC 2013
On Thu, 2013-08-22 at 09:13 -0400, Robert Yang wrote:
> Let debugfs do sparse copy when src is a sparse file, just like
> "cp --sparse=auto"
>
> This patch has been reviewed by the linux-ext4 mailing list, but isn't
> merged atm.
>
> [YOCTO #3848]
Minor whitespace nit below, but will likely be caught by upstream.
--
Darren
>
> Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
> ---
> .../e2fsprogs-1.42.8/debugfs-sparse-copy.patch | 147 ++++++++++++++++++++
> .../recipes-devtools/e2fsprogs/e2fsprogs_1.42.8.bb | 1 +
> 2 files changed, 148 insertions(+)
> create mode 100644 meta/recipes-devtools/e2fsprogs/e2fsprogs-1.42.8/debugfs-sparse-copy.patch
>
> diff --git a/meta/recipes-devtools/e2fsprogs/e2fsprogs-1.42.8/debugfs-sparse-copy.patch b/meta/recipes-devtools/e2fsprogs/e2fsprogs-1.42.8/debugfs-sparse-copy.patch
> new file mode 100644
> index 0000000..c87bcbf
> --- /dev/null
> +++ b/meta/recipes-devtools/e2fsprogs/e2fsprogs-1.42.8/debugfs-sparse-copy.patch
> @@ -0,0 +1,147 @@
> +debugfs.c: do sparse copy when src is a sparse file
> +
> +Let debugfs do sparse copy when src is a sparse file, just like
> +"cp --sparse=auto"
> +
> +* For the:
> + #define IO_BUFSIZE 64*1024
> + this is a suggested value from gnu coreutils:
> + http://git.savannah.gnu.org/gitweb/?p=coreutils.git;a=blob;f=src/ioblksize.h;h=1ae93255e7d0ccf0855208c7ae5888209997bf16;hb=HEAD
> +
> +* Use malloc() to allocate memory for the buffer since put 64K (or
> + more) on the stack seems not a good idea.
> +
> +Upstream-Status: Submitted
> +
> +Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
> +Acked-by: Darren Hart <dvhart at linux.intel.com>
> +---
> + debugfs/debugfs.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++----
> + 1 file changed, 57 insertions(+), 4 deletions(-)
> +
> +diff --git a/debugfs/debugfs.c b/debugfs/debugfs.c
> +--- a/debugfs/debugfs.c
> ++++ b/debugfs/debugfs.c
> +@@ -41,6 +41,16 @@ extern char *optarg;
> + #define BUFSIZ 8192
> + #endif
> +
> ++/* 64KiB is the minimium blksize to best minimize system call overhead. */
> ++#ifndef IO_BUFSIZE
> ++#define IO_BUFSIZE 64*1024
> ++#endif
> ++
> ++/* Block size for `st_blocks' */
> ++#ifndef S_BLKSIZE
> ++#define S_BLKSIZE 512
> ++#endif
> ++
> + ss_request_table *extra_cmds;
> + const char *debug_prog_name;
> + int sci_idx;
> +@@ -1575,22 +1585,36 @@ void do_find_free_inode(int argc, char *argv[])
> + }
> +
> + #ifndef READ_ONLY
> +-static errcode_t copy_file(int fd, ext2_ino_t newfile)
> ++static errcode_t copy_file(int fd, ext2_ino_t newfile, int bufsize, int make_holes)
> + {
> + ext2_file_t e2_file;
> + errcode_t retval;
> + int got;
> + unsigned int written;
> +- char buf[8192];
> ++ char *buf;
> + char *ptr;
> ++ char *zero_buf;
> ++ int cmp;
> +
> + retval = ext2fs_file_open(current_fs, newfile,
> + EXT2_FILE_WRITE, &e2_file);
> + if (retval)
> + return retval;
> +
> ++ if (!(buf = (char *) malloc(bufsize))){
> ++ com_err("copy_file", errno, "can't allocate buffer\n");
> ++ return;
> ++ }
> ++
> ++ /* This is used for checking whether the whole block is zero */
Whitespace/indentation error ^
> ++ retval = ext2fs_get_memzero(bufsize, &zero_buf);
> ++ if (retval) {
> ++ com_err("copy_file", retval, "can't allocate buffer\n");
> ++ return retval;
> ++ }
> ++
> + while (1) {
> +- got = read(fd, buf, sizeof(buf));
> ++ got = read(fd, buf, bufsize);
> + if (got == 0)
> + break;
> + if (got < 0) {
> +@@ -1598,6 +1622,21 @@ static errcode_t copy_file(int fd, ext2_ino_t newfile)
> + goto fail;
> + }
> + ptr = buf;
> ++
> ++ /* Sparse copy */
> ++ if (make_holes) {
> ++ /* Check whether all is zero */
> ++ cmp = memcmp(ptr, zero_buf, got);
> ++ if (cmp == 0) {
> ++ /* The whole block is zero, make a hole */
> ++ retval = ext2fs_file_lseek(e2_file, got, EXT2_SEEK_CUR, NULL);
> ++ if (retval)
> ++ goto fail;
> ++ got = 0;
> ++ }
> ++ }
> ++
> ++ /* Normal copy */
> + while (got > 0) {
> + retval = ext2fs_file_write(e2_file, ptr,
> + got, &written);
> +@@ -1608,10 +1647,14 @@ static errcode_t copy_file(int fd, ext2_ino_t newfile)
> + ptr += written;
> + }
> + }
> ++ free(buf);
> ++ ext2fs_free_mem(&zero_buf);
> + retval = ext2fs_file_close(e2_file);
> + return retval;
> +
> + fail:
> ++ free(buf);
> ++ ext2fs_free_mem(&zero_buf);
> + (void) ext2fs_file_close(e2_file);
> + return retval;
> + }
> +@@ -1624,6 +1667,8 @@ void do_write(int argc, char *argv[])
> + ext2_ino_t newfile;
> + errcode_t retval;
> + struct ext2_inode inode;
> ++ int bufsize = IO_BUFSIZE;
> ++ int make_holes = 0;
> +
> + if (common_args_process(argc, argv, 3, 3, "write",
> + "<native file> <new file>", CHECK_FS_RW))
> +@@ -1699,7 +1744,15 @@ void do_write(int argc, char *argv[])
> + return;
> + }
> + if (LINUX_S_ISREG(inode.i_mode)) {
> +- retval = copy_file(fd, newfile);
> ++ if (statbuf.st_blocks < statbuf.st_size / S_BLKSIZE) {
> ++ make_holes = 1;
> ++ /*
> ++ * Use I/O blocksize as buffer size when
> ++ * copying sparse files.
> ++ */
> ++ bufsize = statbuf.st_blksize;
> ++ }
> ++ retval = copy_file(fd, newfile, bufsize, make_holes);
> + if (retval)
> + com_err("copy_file", retval, 0);
> + }
> +--
> +1.8.1.2
> +
> diff --git a/meta/recipes-devtools/e2fsprogs/e2fsprogs_1.42.8.bb b/meta/recipes-devtools/e2fsprogs/e2fsprogs_1.42.8.bb
> index f97de7f..5d65bbc 100644
> --- a/meta/recipes-devtools/e2fsprogs/e2fsprogs_1.42.8.bb
> +++ b/meta/recipes-devtools/e2fsprogs/e2fsprogs_1.42.8.bb
> @@ -4,6 +4,7 @@ require e2fsprogs.inc
> SRC_URI += "file://acinclude.m4 \
> file://remove.ldconfig.call.patch \
> file://debugfs-too-short.patch \
> + file://debugfs-sparse-copy.patch \
> "
>
> SRC_URI[md5sum] = "8ef664b6eb698aa6b733df59b17b9ed4"
--
Darren Hart
Intel Open Source Technology Center
Yocto Project - Linux Kernel
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