Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8d3bcd4b authored by Eric Biggers's avatar Eric Biggers
Browse files

fs_mgr: refactor pre-mount logic into prepare_fs_for_mount() 

There were several duplications in the code that runs before a
filesystem is mounted.  This made it difficult to start running tune2fs
to set the encryption feature flag.  Refactor to deduplicate the logic,
and improve the log messages.

Bug: 36231741
Change-Id: I90846dad9c5ec85b3c5460615dec4cc19cb7e198
parent eb42bb8c

fs_mgr/fs_mgr.cpp

+168 −192
Original line number Diff line number Diff line
@@ -78,13 +78,14 @@ enum FsStatFlags { 
    FS_STAT_E2FSCK_F_ALWAYS = 0x0004,

    FS_STAT_UNCLEAN_SHUTDOWN = 0x0008,

    FS_STAT_QUOTA_ENABLED = 0x0010,

    FS_STAT_TUNE2FS_FAILED = 0x0020,

    FS_STAT_RO_MOUNT_FAILED = 0x0040,

    FS_STAT_RO_UNMOUNT_FAILED = 0x0080,

    FS_STAT_FULL_MOUNT_FAILED = 0x0100,

    FS_STAT_E2FSCK_FAILED = 0x0200,

    FS_STAT_E2FSCK_FS_FIXED = 0x0400,

    FS_STAT_EXT4_INVALID_MAGIC = 0x0800,

    FS_STAT_TOGGLE_QUOTAS_FAILED = 0x10000,

    FS_STAT_SET_RESERVED_BLOCKS_FAILED = 0x20000,

};



/*
@@ -128,10 +129,15 @@ static void log_fs_stat(const char* blk_device, int fs_stat) 
    }

}



static bool is_extfs(const std::string& fs_type) {

    return fs_type == "ext4" || fs_type == "ext3" || fs_type == "ext2";

}



static bool should_force_check(int fs_stat) {

    return fs_stat & (FS_STAT_E2FSCK_F_ALWAYS | FS_STAT_UNCLEAN_SHUTDOWN | FS_STAT_QUOTA_ENABLED |

                      FS_STAT_TUNE2FS_FAILED | FS_STAT_RO_MOUNT_FAILED | FS_STAT_RO_UNMOUNT_FAILED |

                      FS_STAT_FULL_MOUNT_FAILED | FS_STAT_E2FSCK_FAILED);

                      FS_STAT_RO_MOUNT_FAILED | FS_STAT_RO_UNMOUNT_FAILED |

                      FS_STAT_FULL_MOUNT_FAILED | FS_STAT_E2FSCK_FAILED |

                      FS_STAT_TOGGLE_QUOTAS_FAILED | FS_STAT_SET_RESERVED_BLOCKS_FAILED);

}



static void check_fs(const char *blk_device, char *fs_type, char *target, int *fs_stat)
@@ -144,7 +150,7 @@ static void check_fs(const char *blk_device, char *fs_type, char *target, int *f 
    const char* e2fsck_forced_argv[] = {E2FSCK_BIN, "-f", "-y", blk_device};



    /* Check for the types of filesystems we know how to check */

    if (!strcmp(fs_type, "ext2") || !strcmp(fs_type, "ext3") || !strcmp(fs_type, "ext4")) {

    if (is_extfs(fs_type)) {

        if (*fs_stat & FS_STAT_EXT4_INVALID_MAGIC) {  // will fail, so do not try

            return;

        }
@@ -242,186 +248,181 @@ static void check_fs(const char *blk_device, char *fs_type, char *target, int *f 
    return;

}



/* Function to read the primary superblock */

static int read_super_block(int fd, struct ext4_super_block *sb)

{

    off64_t ret;



    ret = lseek64(fd, 1024, SEEK_SET);

    if (ret < 0)

        return ret;



    ret = read(fd, sb, sizeof(*sb));

    if (ret < 0)

        return ret;

    if (ret != sizeof(*sb))

        return ret;



    return 0;

}



static ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)

{

static ext4_fsblk_t ext4_blocks_count(const struct ext4_super_block* es) {

    return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |

           le32_to_cpu(es->s_blocks_count_lo);

}



static ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)

{

static ext4_fsblk_t ext4_r_blocks_count(const struct ext4_super_block* es) {

    return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |

           le32_to_cpu(es->s_r_blocks_count_lo);

}



static int do_quota_with_shutdown_check(char *blk_device, char *fs_type,

                                        struct fstab_rec *rec, int *fs_stat)

{

    int force_check = 0;

    if (!strcmp(fs_type, "ext4")) {

        /*

         * Some system images do not have tune2fs for licensing reasons

         * Detect these and skip reserve blocks.

         */

        if (access(TUNE2FS_BIN, X_OK)) {

            LERROR << "Not running " << TUNE2FS_BIN << " on "

                   << blk_device << " (executable not in system image)";

        } else {

            const char* arg1 = nullptr;

            const char* arg2 = nullptr;

            int status = 0;

            int ret = 0;

            android::base::unique_fd fd(

                TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC)));

            if (fd >= 0) {

                struct ext4_super_block sb;

                ret = read_super_block(fd, &sb);

                if (ret < 0) {

// Read the primary superblock from an ext4 filesystem.  On failure return

// false.  If it's not an ext4 filesystem, also set FS_STAT_EXT4_INVALID_MAGIC.

static bool read_ext4_superblock(const char* blk_device, struct ext4_super_block* sb, int* fs_stat) {

    android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC)));



    if (fd < 0) {

        PERROR << "Failed to open '" << blk_device << "'";

        return false;

    }



    if (pread(fd, sb, sizeof(*sb), 1024) != sizeof(*sb)) {

        PERROR << "Can't read '" << blk_device << "' superblock";

                    return force_check;

        return false;

    }

                if (sb.s_magic != EXT4_SUPER_MAGIC) {

                    LINFO << "Invalid ext4 magic:0x" << std::hex << sb.s_magic << "," << blk_device;



    if (sb->s_magic != EXT4_SUPER_MAGIC) {

        LINFO << "Invalid ext4 magic:0x" << std::hex << sb->s_magic << " "

              << "on '" << blk_device << "'";

        // not a valid fs, tune2fs, fsck, and mount  will all fail.

        *fs_stat |= FS_STAT_EXT4_INVALID_MAGIC;

                    return 0;  // not a valid fs, tune2fs, fsck, and mount  will all fail.

        return false;

    }

    *fs_stat |= FS_STAT_IS_EXT4;

                LINFO << "superblock s_max_mnt_count:" << sb.s_max_mnt_count << "," << blk_device;

                if (sb.s_max_mnt_count == 0xffff) {  // -1 (int16) in ext2, but uint16 in ext4

    LINFO << "superblock s_max_mnt_count:" << sb->s_max_mnt_count << "," << blk_device;

    if (sb->s_max_mnt_count == 0xffff) {  // -1 (int16) in ext2, but uint16 in ext4

        *fs_stat |= FS_STAT_NEW_IMAGE_VERSION;

    }

                if ((sb.s_feature_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) != 0 ||

                    (sb.s_state & EXT4_VALID_FS) == 0) {

                    LINFO << __FUNCTION__ << "(): was not clealy shutdown, state flag:"

                          << std::hex << sb.s_state

                          << "incompat flag:" << std::hex << sb.s_feature_incompat;

                    force_check = 1;

                    *fs_stat |= FS_STAT_UNCLEAN_SHUTDOWN;

    return true;

}

                int has_quota = (sb.s_feature_ro_compat

                        & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_QUOTA)) != 0;

                int want_quota = fs_mgr_is_quota(rec) != 0;



// Some system images do not have tune2fs for licensing reasons.

// Detect these and skip running it.

static bool tune2fs_available(void) {

    return access(TUNE2FS_BIN, X_OK) == 0;

}



static bool run_tune2fs(const char* argv[], int argc) {

    int ret;



    ret = android_fork_execvp_ext(argc, const_cast<char**>(argv), nullptr, true,

                                  LOG_KLOG | LOG_FILE, true, nullptr, nullptr, 0);

    return ret == 0;

}



// Enable/disable quota support on the filesystem if needed.

static void tune_quota(const char* blk_device, const struct fstab_rec* rec,

                       const struct ext4_super_block* sb, int* fs_stat) {

    bool has_quota = (sb->s_feature_ro_compat & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_QUOTA)) != 0;

    bool want_quota = fs_mgr_is_quota(rec) != 0;



    if (has_quota == want_quota) {

                    LINFO << "Requested quota status is match on " << blk_device;

                    return force_check;

                } else if (want_quota) {

                    LINFO << "Enabling quota on " << blk_device;

                    arg1 = "-Oquota";

                    arg2 = "-Qusrquota,grpquota";

                    force_check = 1;

                    *fs_stat |= FS_STAT_QUOTA_ENABLED;

                } else {

                    LINFO << "Disabling quota on " << blk_device;

                    arg1 = "-Q^usrquota,^grpquota";

                    arg2 = "-O^quota";

        return;

    }



    if (!tune2fs_available()) {

        LERROR << "Unable to " << (want_quota ? "enable" : "disable") << " quotas on " << blk_device

               << " because " TUNE2FS_BIN " is missing";

        return;

    }



    const char* argv[] = {TUNE2FS_BIN, nullptr, nullptr, blk_device};



    if (want_quota) {

        LINFO << "Enabling quotas on " << blk_device;

        argv[1] = "-Oquota";

        argv[2] = "-Qusrquota,grpquota";

        *fs_stat |= FS_STAT_QUOTA_ENABLED;

    } else {

                PERROR << "Failed to open '" << blk_device << "'";

                return force_check;

        LINFO << "Disabling quotas on " << blk_device;

        argv[1] = "-O^quota";

        argv[2] = "-Q^usrquota,^grpquota";

    }



            const char *tune2fs_argv[] = {

                TUNE2FS_BIN,

                arg1,

                arg2,

                blk_device,

            };

            ret = android_fork_execvp_ext(ARRAY_SIZE(tune2fs_argv),

                                          const_cast<char **>(tune2fs_argv),

                                          &status, true, LOG_KLOG | LOG_FILE,

                                          true, NULL, NULL, 0);

            if (ret < 0) {

                /* No need to check for error in fork, we can't really handle it now */

                LERROR << "Failed trying to run " << TUNE2FS_BIN;

                *fs_stat |= FS_STAT_TUNE2FS_FAILED;

    if (!run_tune2fs(argv, ARRAY_SIZE(argv))) {

        LERROR << "Failed to run " TUNE2FS_BIN " to " << (want_quota ? "enable" : "disable")

               << " quotas on " << blk_device;

        *fs_stat |= FS_STAT_TOGGLE_QUOTAS_FAILED;

    }

}



// Set the number of reserved filesystem blocks if needed.

static void tune_reserved_size(const char* blk_device, const struct fstab_rec* rec,

                               const struct ext4_super_block* sb, int* fs_stat) {

    if (!(rec->fs_mgr_flags & MF_RESERVEDSIZE)) {

        return;

    }

    return force_check;



    // The size to reserve is given in the fstab, but we won't reserve more

    // than 2% of the filesystem.

    const uint64_t max_reserved_blocks = ext4_blocks_count(sb) * 0.02;

    uint64_t reserved_blocks = rec->reserved_size / EXT4_BLOCK_SIZE(sb);



    if (reserved_blocks > max_reserved_blocks) {

        LWARNING << "Reserved blocks " << reserved_blocks << " is too large; "

                 << "capping to " << max_reserved_blocks;

        reserved_blocks = max_reserved_blocks;

    }



static void do_reserved_size(char *blk_device, char *fs_type, struct fstab_rec *rec, int *fs_stat)

{

    /* Check for the types of filesystems we know how to check */

    if (!strcmp(fs_type, "ext2") || !strcmp(fs_type, "ext3") || !strcmp(fs_type, "ext4")) {

        /*

         * Some system images do not have tune2fs for licensing reasons

         * Detect these and skip reserve blocks.

         */

        if (access(TUNE2FS_BIN, X_OK)) {

            LERROR << "Not running " << TUNE2FS_BIN << " on "

                   << blk_device << " (executable not in system image)";

        } else {

            LINFO << "Running " << TUNE2FS_BIN << " on " << blk_device;

    if (ext4_r_blocks_count(sb) == reserved_blocks) {

        return;

    }



            int status = 0;

            int ret = 0;

            unsigned long reserved_blocks = 0;

            android::base::unique_fd fd(

                TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC)));

            if (fd >= 0) {

                struct ext4_super_block sb;

                ret = read_super_block(fd, &sb);

                if (ret < 0) {

                    PERROR << "Can't read '" << blk_device << "' super block";

    if (!tune2fs_available()) {

        LERROR << "Unable to set the number of reserved blocks on " << blk_device

               << " because " TUNE2FS_BIN " is missing";

        return;

    }

                reserved_blocks = rec->reserved_size / EXT4_BLOCK_SIZE(&sb);

                unsigned long reserved_threshold = ext4_blocks_count(&sb) * 0.02;

                if (reserved_threshold < reserved_blocks) {

                    LWARNING << "Reserved blocks " << reserved_blocks

                             << " is too large";

                    reserved_blocks = reserved_threshold;



    char buf[32];

    const char* argv[] = {TUNE2FS_BIN, "-r", buf, blk_device};



    snprintf(buf, sizeof(buf), "%" PRIu64, reserved_blocks);

    LINFO << "Setting reserved block count on " << blk_device << " to " << reserved_blocks;

    if (!run_tune2fs(argv, ARRAY_SIZE(argv))) {

        LERROR << "Failed to run " TUNE2FS_BIN " to set the number of reserved blocks on "

               << blk_device;

        *fs_stat |= FS_STAT_SET_RESERVED_BLOCKS_FAILED;

    }

}



                if (ext4_r_blocks_count(&sb) == reserved_blocks) {

                    LINFO << "Have reserved same blocks";

                    return;

//

// Prepare the filesystem on the given block device to be mounted.

//

// If the "check" option was given in the fstab record, or it seems that the

// filesystem was uncleanly shut down, we'll run fsck on the filesystem.

//

// If needed, we'll also enable (or disable) filesystem features as specified by

// the fstab record.

//

static int prepare_fs_for_mount(const char* blk_device, const struct fstab_rec* rec) {

    int fs_stat = 0;



    if (is_extfs(rec->fs_type)) {

        struct ext4_super_block sb;



        if (read_ext4_superblock(blk_device, &sb, &fs_stat)) {

            if ((sb.s_feature_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) != 0 ||

                (sb.s_state & EXT4_VALID_FS) == 0) {

                LINFO << "Filesystem on " << blk_device << " was not cleanly shutdown; "

                      << "state flags: 0x" << std::hex << sb.s_state << ", "

                      << "incompat feature flags: 0x" << std::hex << sb.s_feature_incompat;

                fs_stat |= FS_STAT_UNCLEAN_SHUTDOWN;

            }



            // Note: quotas should be enabled before running fsck.

            tune_quota(blk_device, rec, &sb, &fs_stat);

        } else {

                PERROR << "Failed to open '" << blk_device << "'";

                return;

            return fs_stat;

        }

    }



            char buf[16] = {0};

            snprintf(buf, sizeof (buf), "-r %lu", reserved_blocks);

            const char *tune2fs_argv[] = {

                TUNE2FS_BIN,

                buf,

                blk_device,

            };

    if ((rec->fs_mgr_flags & MF_CHECK) ||

        (fs_stat & (FS_STAT_UNCLEAN_SHUTDOWN | FS_STAT_QUOTA_ENABLED))) {

        check_fs(blk_device, rec->fs_type, rec->mount_point, &fs_stat);

    }



            ret = android_fork_execvp_ext(ARRAY_SIZE(tune2fs_argv),

                                          const_cast<char **>(tune2fs_argv),

                                          &status, true, LOG_KLOG | LOG_FILE,

                                          true, NULL, NULL, 0);

    if (is_extfs(rec->fs_type) && (rec->fs_mgr_flags & MF_RESERVEDSIZE)) {

        struct ext4_super_block sb;



            if (ret < 0) {

                /* No need to check for error in fork, we can't really handle it now */

                LERROR << "Failed trying to run " << TUNE2FS_BIN;

                *fs_stat |= FS_STAT_TUNE2FS_FAILED;

            }

        if (read_ext4_superblock(blk_device, &sb, &fs_stat)) {

            tune_reserved_size(blk_device, rec, &sb, &fs_stat);

        }

    }



    return fs_stat;

}



static void remove_trailing_slashes(char *n)
@@ -559,10 +560,7 @@ static int mount_with_alternatives(struct fstab *fstab, int start_idx, int *end_ 
                continue;

            }



            int fs_stat = 0;

            int force_check = do_quota_with_shutdown_check(fstab->recs[i].blk_device,

                                                           fstab->recs[i].fs_type,

                                                           &fstab->recs[i], &fs_stat);

            int fs_stat = prepare_fs_for_mount(fstab->recs[i].blk_device, &fstab->recs[i]);

            if (fs_stat & FS_STAT_EXT4_INVALID_MAGIC) {

                LERROR << __FUNCTION__ << "(): skipping mount, invalid ext4, mountpoint="

                       << fstab->recs[i].mount_point << " rec[" << i
@@ -570,15 +568,6 @@ static int mount_with_alternatives(struct fstab *fstab, int start_idx, int *end_ 
                mount_errno = EINVAL;  // continue bootup for FDE

                continue;

            }

            if ((fstab->recs[i].fs_mgr_flags & MF_CHECK) || force_check) {

                check_fs(fstab->recs[i].blk_device, fstab->recs[i].fs_type,

                         fstab->recs[i].mount_point, &fs_stat);

            }



            if (fstab->recs[i].fs_mgr_flags & MF_RESERVEDSIZE) {

                do_reserved_size(fstab->recs[i].blk_device, fstab->recs[i].fs_type,

                                 &fstab->recs[i], &fs_stat);

            }



            int retry_count = 2;

            while (retry_count-- > 0) {
@@ -817,9 +806,7 @@ int fs_mgr_mount_all(struct fstab *fstab, int mount_mode) 
        }



        /* Translate LABEL= file system labels into block devices */

        if (!strcmp(fstab->recs[i].fs_type, "ext2") ||

            !strcmp(fstab->recs[i].fs_type, "ext3") ||

            !strcmp(fstab->recs[i].fs_type, "ext4")) {

        if (is_extfs(fstab->recs[i].fs_type)) {

            int tret = translate_ext_labels(&fstab->recs[i]);

            if (tret < 0) {

                LERROR << "Could not translate label to block device";
@@ -1035,18 +1022,7 @@ int fs_mgr_do_mount(struct fstab *fstab, const char *n_name, char *n_blk_device, 
            wait_for_file(n_blk_device, WAIT_TIMEOUT);

        }



        int fs_stat = 0;

        int force_check = do_quota_with_shutdown_check(n_blk_device, fstab->recs[i].fs_type,

                                                       &fstab->recs[i], &fs_stat);



        if ((fstab->recs[i].fs_mgr_flags & MF_CHECK) || force_check) {

            check_fs(n_blk_device, fstab->recs[i].fs_type,

                     fstab->recs[i].mount_point, &fs_stat);

        }



        if (fstab->recs[i].fs_mgr_flags & MF_RESERVEDSIZE) {

            do_reserved_size(n_blk_device, fstab->recs[i].fs_type, &fstab->recs[i], &fs_stat);

        }

        int fs_stat = prepare_fs_for_mount(n_blk_device, &fstab->recs[i]);



        if (fstab->recs[i].fs_mgr_flags & MF_AVB) {

            if (!avb_handle) {

fs_mgr/fs_mgr_fstab.cpp

+6 −12
Original line number Diff line number Diff line
@@ -810,32 +810,26 @@ int fs_mgr_is_noemulatedsd(const struct fstab_rec *fstab) 
    return fstab->fs_mgr_flags & MF_NOEMULATEDSD;

}



int fs_mgr_is_notrim(struct fstab_rec *fstab)

{

int fs_mgr_is_notrim(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & MF_NOTRIM;

}



int fs_mgr_is_formattable(struct fstab_rec *fstab)

{

int fs_mgr_is_formattable(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & (MF_FORMATTABLE);

}



int fs_mgr_is_slotselect(struct fstab_rec *fstab)

{

int fs_mgr_is_slotselect(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & MF_SLOTSELECT;

}



int fs_mgr_is_nofail(struct fstab_rec *fstab)

{

int fs_mgr_is_nofail(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & MF_NOFAIL;

}



int fs_mgr_is_latemount(struct fstab_rec *fstab)

{

int fs_mgr_is_latemount(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & MF_LATEMOUNT;

}



int fs_mgr_is_quota(struct fstab_rec *fstab)

{

int fs_mgr_is_quota(const struct fstab_rec* fstab) {

    return fstab->fs_mgr_flags & MF_QUOTA;

}

fs_mgr/include_fstab/fstab/fstab.h

+6 −6
Original line number Diff line number Diff line
@@ -80,12 +80,12 @@ int fs_mgr_is_file_encrypted(const struct fstab_rec* fstab); 
const char* fs_mgr_get_file_encryption_mode(const struct fstab_rec* fstab);

int fs_mgr_is_convertible_to_fbe(const struct fstab_rec* fstab);

int fs_mgr_is_noemulatedsd(const struct fstab_rec* fstab);

int fs_mgr_is_notrim(struct fstab_rec* fstab);

int fs_mgr_is_formattable(struct fstab_rec* fstab);

int fs_mgr_is_slotselect(struct fstab_rec* fstab);

int fs_mgr_is_nofail(struct fstab_rec* fstab);

int fs_mgr_is_latemount(struct fstab_rec* fstab);

int fs_mgr_is_quota(struct fstab_rec* fstab);

int fs_mgr_is_notrim(const struct fstab_rec* fstab);

int fs_mgr_is_formattable(const struct fstab_rec* fstab);

int fs_mgr_is_slotselect(const struct fstab_rec* fstab);

int fs_mgr_is_nofail(const struct fstab_rec* fstab);

int fs_mgr_is_latemount(const struct fstab_rec* fstab);

int fs_mgr_is_quota(const struct fstab_rec* fstab);



__END_DECLS