Whamcloud - gitweb
filefrag: improvements to filefrag FIEMAP handling
authorAndreas Dilger <adilger@whamcloud.com>
Thu, 22 Nov 2012 15:06:12 +0000 (15:06 +0000)
committerTheodore Ts'o <tytso@mit.edu>
Sun, 30 Dec 2012 03:41:41 +0000 (22:41 -0500)
Update the filefrag program to allow displaying the extents in
some different formats.  Try and stay within 80 columns.
* add -k option to print extents in kB-sized units (like df -k)
* add -b {blocksize} to print extents in blocksize units
* add -e option to print extent format, even when FIBMAP is used
* add -X option to print extents in hexadecimal format

Internally, the FIBMAP handling code has been moved into its own
function like FIEMAP, so that the code is more modular.  Extent
offsets are now handled in bytes instead of in blocks, to allow
printing extents with arbitrary block sizes.  The extent header
printing also moved into its own function so that it can be shared
between the FIEMAP and FIBMAP handling routines, since it got more
complex with the different output options.

Only print error about FIBMAP being root-only a single time.
Print the filesystem type if it changes between specified files.
Add fsync() for FIBMAP if "-s" is given.

Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
misc/filefrag.8.in
misc/filefrag.c

index 463f731..a6d7b27 100644 (file)
@@ -5,7 +5,10 @@ filefrag \- report on file fragmentation
 .SH SYNOPSIS
 .B filefrag
 [
-.B \-Bbsvx
+.BI \-b blocksize
+]
+[
+.B \-BeksvxX
 ]
 [
 .I files...
@@ -27,8 +30,21 @@ If FIEMAP is not supported then filefrag will fall back to using FIBMAP.
 Force the use of the older FIBMAP ioctl instead of the FIEMAP ioctl for
 testing purposes.
 .TP
-.B \-b
-Use 1024 byte blocksize for the output.
+.BI \-b blocksize
+Use
+.I blocksize
+in bytes for output instead of the filesystem blocksize.
+For compatibility with earlier versions of
+.BR filefrag ,
+if
+.I blocksize
+is unspecified it defaults to 1024 bytes.
+.TP
+.B \-e
+Print output in extent format, even for block-mapped files.
+.TP
+.BI \-k
+Use 1024\-byte blocksize for output (identical to '\-b 1024').
 .TP
 .B \-s
 Sync the file before requesting the mapping.
@@ -38,6 +54,9 @@ Be verbose when checking for file fragmentation.
 .TP
 .B \-x
 Display mapping of extended attributes.
+.TP
+.B \-X
+Display extent block numbers in hexadecimal format.
 .SH AUTHOR
 .B filefrag
 was written by Theodore Ts'o <tytso@mit.edu>.
index 56985a1..13f5e15 100644 (file)
@@ -16,8 +16,8 @@
 #include <unistd.h>
 
 int main(void) {
-    fputs("This program is only supported on Linux!\n", stderr);
-    exit(EXIT_FAILURE);
+       fputs("This program is only supported on Linux!\n", stderr);
+       exit(EXIT_FAILURE);
 }
 #else
 #define _LARGEFILE64_SOURCE
@@ -40,23 +40,28 @@ extern int optind;
 #include <sys/vfs.h>
 #include <sys/ioctl.h>
 #include <linux/fd.h>
+#include <ext2fs/ext2fs.h>
 #include <ext2fs/ext2_types.h>
 #include <ext2fs/fiemap.h>
 
 int verbose = 0;
-int no_bs = 0;         /* Don't use the files blocksize, use 1K blocksize */
+int blocksize;         /* Use specified blocksize (default 1kB) */
 int sync_file = 0;     /* fsync file before getting the mapping */
 int xattr_map = 0;     /* get xattr mapping */
-int force_bmap = 0;
-int logical_width = 12;
-int physical_width = 14;
-unsigned long long filesize;
+int force_bmap;        /* force use of FIBMAP instead of FIEMAP */
+int force_extent;      /* print output in extent format always */
+int logical_width = 8;
+int physical_width = 10;
+char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
+char *hex_fmt = "%4d: %*llx..%*llx: %*llx..%*llx: %6llx: %s\n";
 
 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
 
 #define FIBMAP         _IO(0x00, 1)    /* bmap access */
 #define FIGETBSZ       _IO(0x00, 2)    /* get the block size used for bmap */
 
+#define LUSTRE_SUPER_MAGIC 0x0BD00BD0
+
 #define        EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 #define        EXT3_IOC_GETFLAGS               _IOR('f', 1, long)
 
@@ -102,30 +107,47 @@ static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
                if (errno == EPERM) {
                        fprintf(stderr, "No permission to use FIBMAP ioctl; "
                                "must have root privileges\n");
-                       exit(1);
                }
-               perror("FIBMAP");
        }
        *phy_blk = b;
 
        return ret;
 }
 
+static void print_extent_header(void)
+{
+       printf(" ext: %*s %*s length: %*s flags:\n",
+              logical_width * 2 + 3,
+              "logical_offset:",
+              physical_width * 2 + 3, "physical_offset:",
+              physical_width + 1,
+              "expected:");
+}
+
 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
-                             unsigned long long expected, int blk_shift)
+                             unsigned long long expected, int blk_shift,
+                             ext2fs_struct_stat *st)
 {
-       __u64 phy_blk;
+       unsigned long long physical_blk;
        unsigned long long logical_blk;
-       unsigned long ext_len;
+       unsigned long long ext_len;
+       unsigned long long ext_blks;
        char flags[256] = "";
 
-       /* For inline data all offsets should be in terms of bytes, not blocks */
+       /* For inline data all offsets should be in bytes, not blocks */
        if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
                blk_shift = 0;
 
        ext_len = fm_extent->fe_length >> blk_shift;
+       ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
        logical_blk = fm_extent->fe_logical >> blk_shift;
-       phy_blk = fm_extent->fe_physical >> blk_shift;
+       physical_blk = fm_extent->fe_physical >> blk_shift;
+
+       if (expected)
+               sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
+                       physical_width, expected >> blk_shift);
+       else
+               sprintf(flags, "%.*s  ", physical_width, "                   ");
 
        if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN)
                strcat(flags, "unknown,");
@@ -144,28 +166,24 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
        if (fm_extent->fe_flags & FIEMAP_EXTENT_MERGED)
                strcat(flags, "merged,");
 
-       if (fm_extent->fe_logical + fm_extent->fe_length >= filesize)
+       if (fm_extent->fe_logical + fm_extent->fe_length >= st->st_size)
                strcat(flags, "eof,");
 
        /* Remove trailing comma, if any */
        if (flags[0])
                flags[strlen(flags) - 1] = '\0';
 
-       if (expected)
-               printf("%4d %*llu %*llu %*llu %6lu %s\n",
-                      cur_ex, logical_width, logical_blk,
-                      physical_width, phy_blk, physical_width, expected,
-                      ext_len, flags);
-       else
-               printf("%4d %*llu %*llu %*s %6lu %s\n",
-                      cur_ex, logical_width, logical_blk,
-                      physical_width, phy_blk, physical_width, "",
-                      ext_len, flags);
+       printf(ext_fmt, cur_ex, logical_width, logical_blk,
+              logical_width, logical_blk + ext_blks,
+              physical_width, physical_blk,
+              physical_width, physical_blk + ext_blks,
+              ext_len, flags);
 }
 
-static int filefrag_fiemap(int fd, int blk_shift, int *num_extents)
+static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
+                          ext2fs_struct_stat *st)
 {
-       char buf[4096] = "";
+       char buf[16384];
        struct fiemap *fiemap = (struct fiemap *)buf;
        struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
        int count = (sizeof(buf) - sizeof(*fiemap)) /
@@ -206,21 +224,13 @@ static int filefrag_fiemap(int fd, int blk_shift, int *num_extents)
                        break;
 
                if (verbose && !fiemap_header_printed) {
-                       printf(" ext %*s %*s %*s length flags\n", logical_width,
-                              "logical", physical_width, "physical",
-                              physical_width, "expected");
+                       print_extent_header();
                        fiemap_header_printed = 1;
                }
 
                for (i = 0; i < fiemap->fm_mapped_extents; i++) {
-                       __u64 phy_blk, logical_blk;
-                       unsigned long ext_len;
-
-                       phy_blk = fm_ext[i].fe_physical >> blk_shift;
-                       ext_len = fm_ext[i].fe_length >> blk_shift;
-                       logical_blk = fm_ext[i].fe_logical >> blk_shift;
-
-                       if (logical_blk && phy_blk != expected) {
+                       if (fm_ext[i].fe_logical != 0 &&
+                           fm_ext[i].fe_physical != expected) {
                                tot_extents++;
                        } else {
                                expected = 0;
@@ -229,16 +239,16 @@ static int filefrag_fiemap(int fd, int blk_shift, int *num_extents)
                        }
                        if (verbose)
                                print_extent_info(&fm_ext[i], n, expected,
-                                                 blk_shift);
+                                                 blk_shift, st);
 
-                       expected = phy_blk + ext_len;
+                       expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
                        if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
                                last = 1;
                        n++;
                }
 
-               fiemap->fm_start = (fm_ext[i-1].fe_logical +
-                                   fm_ext[i-1].fe_length);
+               fiemap->fm_start = (fm_ext[i - 1].fe_logical +
+                                   fm_ext[i - 1].fe_length);
        } while (last == 0);
 
        *num_extents = tot_extents;
@@ -248,26 +258,95 @@ static int filefrag_fiemap(int fd, int blk_shift, int *num_extents)
 
 #define EXT2_DIRECT    12
 
+static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
+                          ext2fs_struct_stat *st,
+                          unsigned long numblocks, int is_ext2)
+{
+       struct fiemap_extent    fm_ext;
+       unsigned long           i, last_block;
+       unsigned long long      logical;
+                               /* Blocks per indirect block */
+       const long              bpib = st->st_blksize / 4;
+       int                     count;
+
+       if (force_extent) {
+               memset(&fm_ext, 0, sizeof(fm_ext));
+               fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
+       }
+
+       if (sync_file)
+               fsync(fd);
+
+       for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
+            i < numblocks;
+            i++, logical += st->st_blksize) {
+               unsigned long block = 0;
+               int rc;
+
+               if (is_ext2 && last_block) {
+                       if (((i - EXT2_DIRECT) % bpib) == 0)
+                               last_block++;
+                       if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
+                               last_block++;
+                       if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
+                            (((unsigned long long)bpib) * bpib * bpib)) == 0)
+                               last_block++;
+               }
+               rc = get_bmap(fd, i, &block);
+               if (rc < 0)
+                       return rc;
+               if (block == 0)
+                       continue;
+               if (*num_extents == 0) {
+                       (*num_extents)++;
+                       if (force_extent) {
+                               print_extent_header();
+                               fm_ext.fe_physical = block * st->st_blksize;
+                       }
+               }
+               count++;
+               if (force_extent && last_block != 0 &&
+                   (block != last_block + 1 ||
+                    fm_ext.fe_logical + fm_ext.fe_length != logical)) {
+                       print_extent_info(&fm_ext, *num_extents - 1,
+                                         (last_block + 1) * st->st_blksize,
+                                         blk_shift, st);
+                       fm_ext.fe_logical = logical;
+                       fm_ext.fe_physical = block * st->st_blksize;
+                       fm_ext.fe_length = 0;
+                       (*num_extents)++;
+               } else if (verbose && last_block && (block != last_block + 1)) {
+                       printf("Discontinuity: Block %ld is at %lu (was %lu)\n",
+                              i, block, last_block + 1);
+                       (*num_extents)++;
+               }
+               fm_ext.fe_length += st->st_blksize;
+               last_block = block;
+       }
+
+       if (force_extent)
+               print_extent_info(&fm_ext, *num_extents - 1,
+                                 last_block * st->st_blksize, blk_shift, st);
+
+       return count;
+}
+
 static void frag_report(const char *filename)
 {
-       struct statfs   fsinfo;
-#ifdef HAVE_FSTAT64
-       struct stat64   fileinfo;
-#else
-       struct stat     fileinfo;
-#endif
+       static struct statfs fsinfo;
+       ext2fs_struct_stat st;
+       int             blk_shift;
        int             bs;
        long            fd;
-       unsigned long   block, last_block = 0, numblocks, i, count = 0;
-       long            bpib;   /* Blocks per indirect block */
-       long            cylgroups;
-       int             num_extents = 0, expected;
+       unsigned long   numblocks;
+       int             data_blocks_per_cyl = 1;
+       int             num_extents = 1, expected = ~0;
        int             is_ext2 = 0;
-       static int      once = 1;
+       static dev_t    last_device;
        unsigned int    flags;
-       int rc;
+       int             width;
 
-#ifdef HAVE_OPEN64
+#if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
        fd = open64(filename, O_RDONLY);
 #else
        fd = open(filename, O_RDONLY);
@@ -277,103 +356,98 @@ static void frag_report(const char *filename)
                return;
        }
 
-       if (statfs(filename, &fsinfo) < 0) {
-               perror("statfs");
-               return;
-       }
-#ifdef HAVE_FSTAT64
-       if (stat64(filename, &fileinfo) < 0) {
+#if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
+       if (fstat64(fd, &st) < 0) {
 #else
-       if (stat(filename, &fileinfo) < 0) {
+       if (fstat(fd, &st) < 0) {
 #endif
                perror("stat");
                return;
        }
+
+       if (last_device != st.st_dev) {
+               if (fstatfs(fd, &fsinfo) < 0) {
+                       perror("fstatfs");
+                       return;
+               }
+               if (verbose)
+                       printf("Filesystem type is: %lx\n",
+                              (unsigned long) fsinfo.f_type);
+       }
+       st.st_blksize = fsinfo.f_bsize;
        if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0)
                flags = 0;
        if (!(flags & EXT4_EXTENTS_FL) &&
            ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) ||
             (fsinfo.f_type == 0xef53)))
                is_ext2++;
-       if (verbose && once)
-               printf("Filesystem type is: %lx\n",
-                      (unsigned long) fsinfo.f_type);
-
-       cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize*8);
-       if (verbose && is_ext2 && once)
-               printf("Filesystem cylinder groups is approximately %ld\n",
-                      cylgroups);
-
-       physical_width = int_log10(fsinfo.f_blocks);
-       if (physical_width < 8)
-               physical_width = 8;
-
-       if (ioctl(fd, FIGETBSZ, &bs) < 0) { /* FIGETBSZ takes an int */
-               perror("FIGETBSZ");
-               close(fd);
-               return;
+
+       if (is_ext2) {
+               long cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize * 8);
+
+               if (verbose && last_device != st.st_dev)
+                       printf("Filesystem cylinder groups approximately %ld\n",
+                              cylgroups);
+
+               data_blocks_per_cyl = fsinfo.f_bsize * 8 -
+                                       (fsinfo.f_files / 8 / cylgroups) - 3;
        }
+       last_device = st.st_dev;
+
+       width = int_log10(fsinfo.f_blocks);
+       if (width > physical_width)
+               physical_width = width;
 
-       if (no_bs)
-               bs = 1024;
+       numblocks = (st.st_size + fsinfo.f_bsize - 1) / fsinfo.f_bsize;
+       if (blocksize != 0)
+               blk_shift = int_log2(blocksize);
+       else
+               blk_shift = int_log2(fsinfo.f_bsize);
 
-       bpib = bs / 4;
-       numblocks = (fileinfo.st_size + (bs-1)) / bs;
-       logical_width = int_log10(numblocks);
-       if (logical_width < 7)
-               logical_width = 7;
-       filesize = (long long)fileinfo.st_size;
+       width = int_log10(numblocks);
+       if (width > logical_width)
+               logical_width = width;
        if (verbose)
-               printf("File size of %s is %lld (%ld block%s, blocksize %d)\n",
-                      filename, (long long) fileinfo.st_size, numblocks,
-                      numblocks == 1 ? "" : "s", bs);
+               printf("File size of %s is %llu (%lu block%s of %d bytes)\n",
+                      filename, (unsigned long long)st.st_size,
+                      numblocks * fsinfo.f_bsize >> blk_shift,
+                      numblocks == 1 ? "" : "s", 1 << blk_shift);
+
        if (force_bmap ||
-           filefrag_fiemap(fd, int_log2(bs), &num_extents) != 0) {
-               for (i = 0, count = 0; i < numblocks; i++) {
-                       if (is_ext2 && last_block) {
-                               if (((i-EXT2_DIRECT) % bpib) == 0)
-                                       last_block++;
-                               if (((i-EXT2_DIRECT-bpib) % (bpib*bpib)) == 0)
-                                       last_block++;
-                               if (((i-EXT2_DIRECT-bpib-bpib*bpib) %
-                                    (((__u64) bpib)*bpib*bpib)) == 0)
-                                       last_block++;
-                       }
-                       rc = get_bmap(fd, i, &block);
-                       if (block == 0)
-                               continue;
-                       if (!num_extents)
-                               num_extents++;
-                       count++;
-                       if (last_block && (block != last_block+1) ) {
-                               if (verbose)
-                                       printf("Discontinuity: Block %ld is at "
-                                              "%lu (was %lu)\n",
-                                              i, block, last_block+1);
-                               num_extents++;
+           filefrag_fiemap(fd, blk_shift, &num_extents, &st) != 0) {
+               expected = filefrag_fibmap(fd, blk_shift, &num_extents,
+                                          &st, numblocks, is_ext2);
+               if (expected < 0) {
+                       if (errno == EINVAL || errno == ENOTTY) {
+                               fprintf(stderr, "%s: FIBMAP unsupported\n",
+                                       filename);
+                       } else if (errno != EPERM) {
+                               fprintf(stderr, "%s: FIBMAP error: %s",
+                                       filename, strerror(errno));
                        }
-                       last_block = block;
+                       goto out_close;
                }
+               expected = expected / data_blocks_per_cyl + 1;
        }
+
        if (num_extents == 1)
                printf("%s: 1 extent found", filename);
        else
                printf("%s: %d extents found", filename, num_extents);
        /* count, and thus expected, only set for indirect FIBMAP'd files */
-       if (is_ext2) {
-               expected = (count/((bs*8)-(fsinfo.f_files/8/cylgroups)-3))+1;
-               if (expected && expected < num_extents)
-                       printf(", perfection would be %d extent%s\n", expected,
-                               (expected>1) ? "s" : "");
-       } else
+       if (is_ext2 && expected && expected < num_extents)
+               printf(", perfection would be %d extent%s\n", expected,
+                       (expected > 1) ? "s" : "");
+       else
                fputc('\n', stdout);
+out_close:
        close(fd);
-       once = 0;
 }
 
 static void usage(const char *progname)
 {
-       fprintf(stderr, "Usage: %s [-Bbvsx] file ...\n", progname);
+       fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeklsvxX] file ...\n",
+               progname);
        exit(1);
 }
 
@@ -382,23 +456,61 @@ int main(int argc, char**argv)
        char **cpp;
        int c;
 
-       while ((c = getopt(argc, argv, "Bbsvx")) != EOF)
+       while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF)
                switch (c) {
                case 'B':
                        force_bmap++;
                        break;
                case 'b':
-                       no_bs++;
+                       if (optarg) {
+                               char *end;
+                               blocksize = strtoul(optarg, &end, 0);
+                               if (end) {
+                                       switch (end[0]) {
+                                       case 'g':
+                                       case 'G':
+                                               blocksize *= 1024;
+                                               /* no break */
+                                       case 'm':
+                                       case 'M':
+                                               blocksize *= 1024;
+                                               /* no break */
+                                       case 'k':
+                                       case 'K':
+                                               blocksize *= 1024;
+                                               break;
+                                       default:
+                                               break;
+                                       }
+                               }
+                       } else { /* Allow -b without argument for compat. Remove
+                                 * this eventually so "-b {blocksize}" works */
+                               fprintf(stderr, "%s: -b needs a blocksize "
+                                       "option, assuming 1024-byte blocks.\n",
+                                       argv[0]);
+                               blocksize = 1024;
+                       }
                        break;
-               case 'v':
-                       verbose++;
+               case 'e':
+                       force_extent++;
+                       if (!verbose)
+                               verbose++;
+                       break;
+               case 'k':
+                       blocksize = 1024;
                        break;
                case 's':
                        sync_file++;
                        break;
+               case 'v':
+                       verbose++;
+                       break;
                case 'x':
                        xattr_map++;
                        break;
+               case 'X':
+                       ext_fmt = hex_fmt;
+                       break;
                default:
                        usage(argv[0]);
                        break;