Verified Commit 4bf6860f authored by Marc Vef's avatar Marc Vef
Browse files

Added interception of statfs() and fstatfs() calls. 

ADA-FS's statfs will fill the struct mostly with rough estimations.
It is not supposed to return accurate data but "some" data for applications to work
parent 68fa711b

ifs/include/preload/adafs_functions.hpp

+25 −0
Original line number Diff line number Diff line
@@ -3,6 +3,29 @@ 


#include <preload/preload_util.hpp>



/*

 * See include/linux/statfs.h (not includable)

 *

 * Definitions for the flag in f_flag.

 *

 * Generally these flags are equivalent to the MS_ flags used in the mount

 * ABI.  The exception is ST_VALID which has the same value as MS_REMOUNT

 * which doesn't make any sense for statfs.

 */

#define ST_RDONLY    0x0001    /* mount read-only */

#define ST_NOSUID    0x0002    /* ignore suid and sgid bits */

#define ST_NODEV    0x0004    /* disallow access to device special files */

#define ST_NOEXEC    0x0008    /* disallow program execution */

#define ST_SYNCHRONOUS    0x0010    /* writes are synced at once */

#define ST_VALID    0x0020    /* f_flags support is implemented */

#define ST_MANDLOCK    0x0040    /* allow mandatory locks on an FS */

/* 0x0080 used for ST_WRITE in glibc */

/* 0x0100 used for ST_APPEND in glibc */

/* 0x0200 used for ST_IMMUTABLE in glibc */

#define ST_NOATIME    0x0400    /* do not update access times */

#define ST_NODIRATIME    0x0800    /* do not update directory access times */

#define ST_RELATIME    0x1000    /* update atime relative to mtime/ctime */



int adafs_open(const std::string& path, mode_t mode, int flags);



int adafs_mk_node(const std::string& path, mode_t mode);
@@ -15,6 +38,8 @@ int adafs_stat(const std::string& path, struct stat* buf); 


int adafs_stat64(const std::string& path, struct stat64* buf);



int adafs_statfs(const std::string& path, struct statfs* adafs_buf, struct statfs& realfs_buf);



off64_t adafs_lseek(int fd, off64_t offset, int whence);



off64_t adafs_lseek(std::shared_ptr<OpenFile> adafs_fd, off64_t offset, int whence);

ifs/include/preload/passthrough.hpp

+3 −0
Original line number Diff line number Diff line
@@ -37,6 +37,9 @@ extern void* libc___fxstat64; 
extern void* libc___lxstat;

extern void* libc___lxstat64;



extern void* libc_statfs;

extern void* libc_fstatfs;



extern void* libc_puts;



extern void* libc_write;

ifs/main.cpp

+2 −0
Original line number Diff line number Diff line
@@ -167,6 +167,8 @@ int main(int argc, const char* argv[]) { 
    bfs::create_directories(ADAFS_DATA->inode_path());

    bfs::create_directories(ADAFS_DATA->chunk_path());

    bfs::create_directories(ADAFS_DATA->mgmt_path());

    // Create mountdir. We use this dir to get some information on the underlying fs with statfs in adafs_statfs

    bfs::create_directories(ADAFS_DATA->mountdir());



    if (init_environment()) {

        signal(SIGINT, shutdown_handler);

ifs/src/daemon/adafs_daemon.cpp

+1 −0
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ void destroy_enviroment() { 
    cout << "\n####################\n\nMargo RPC server stats: " << endl;

    margo_diag_dump(RPC_DATA->server_rpc_mid(), "-", 0);

#endif

    bfs::remove_all(ADAFS_DATA->mountdir());

    if (!deregister_daemon_proc())

        ADAFS_DATA->spdlogger()->warn("{}() Unable to clean up auxiliary files", __func__);

    else

ifs/src/preload/adafs_functions.cpp

+36 −2
Original line number Diff line number Diff line
@@ -64,7 +64,7 @@ int adafs_access(const std::string& path, const int mask) { 
}



// TODO combine adafs_stat and adafs_stat64

int adafs_stat(const std::string& path, struct stat* buf) {

int adafs_stat(const string& path, struct stat* buf) {

    init_ld_env_if_needed();

    string attr = ""s;

    auto err = rpc_send_stat(path, attr);
@@ -73,7 +73,7 @@ int adafs_stat(const std::string& path, struct stat* buf) { 
    return err;

}



int adafs_stat64(const std::string& path, struct stat64* buf) {

int adafs_stat64(const string& path, struct stat64* buf) {

    init_ld_env_if_needed();

    string attr = ""s;

    auto err = rpc_send_stat(path, attr);
@@ -82,6 +82,40 @@ int adafs_stat64(const std::string& path, struct stat64* buf) { 
    return err;

}



int adafs_statfs(const string& path, struct statfs* adafs_buf, struct statfs& realfs_buf) {

    // Check that file path exists

    auto ret = rpc_send_access(path, F_OK);

    // Valid fs error

    if (ret > 0) {

        errno = ret;

        return -1;

    }

    // RPC error (errno has been set)

    if (ret < 0)

        return -1;



    // fs object exists. Let's make up some fs values

    adafs_buf->f_type = 0; // fs is not know to VFS. Therefore, no valid specifier possible

    adafs_buf->f_bsize = static_cast<int>(CHUNKSIZE);

    // some rough estimations

    adafs_buf->f_blocks = realfs_buf.f_blocks * fs_config->host_size;

    adafs_buf->f_bfree = realfs_buf.f_bfree * fs_config->host_size;

    adafs_buf->f_bavail = realfs_buf.f_bavail * fs_config->host_size;

    adafs_buf->f_files = realfs_buf.f_files * fs_config->host_size;

    adafs_buf->f_ffree = realfs_buf.f_ffree * fs_config->host_size;

    adafs_buf->f_fsid = realfs_buf.f_fsid; // "Nobody knows what f_fsid is supposed to contain"

    adafs_buf->f_namelen = realfs_buf.f_namelen;

    adafs_buf->f_frsize = realfs_buf.f_frsize;

    adafs_buf->f_spare[0] = 0;

    adafs_buf->f_spare[1] = 0;

    adafs_buf->f_spare[2] = 0;

    adafs_buf->f_spare[3] = 0;

    adafs_buf->f_flags = ST_NOATIME | ST_NOSUID | ST_NODEV | ST_SYNCHRONOUS;

    if (!fs_config->atime_state)

        adafs_buf->f_flags = adafs_buf->f_flags | ST_NOATIME | ST_NODIRATIME;

    return 0;

}



off64_t adafs_lseek(int fd, off64_t offset, int whence) {

    init_ld_env_if_needed();

    return adafs_lseek(file_map.get(fd), offset, whence);