Quoting Pekka J Enberg (penberg@xxxxxxxxxxxxxx): > From: Pekka Enberg <penberg@xxxxxxxxxxxxxx> > > The revokeat(2) and frevoke(2) system calls invalidate open file > descriptors and shared mappings of an inode. After an successful > revocation, operations on file descriptors fail with the EBADF or > ENXIO error code for regular and device files, > respectively. Attempting to read from or write to a revoked mapping > causes SIGBUS. > > The actual operation is done in two passes: > > 1. Revoke all file descriptors that point to the given inode. We do > this under tasklist_lock so that after this pass, we don't need > to worry about racing with close(2) or dup(2). > > 2. Take down shared memory mappings of each revoked file and close > the file pointer. > > The file descriptors are kept until the owning task does close(2) and > memory mapping ranges preserved until the owning task does munmap(2). With the attached patch, this passes all your revoke tests on s390, as well as ltp runalltests.sh. thanks, -serge From: "Serge E. Hallyn" <serue@xxxxxxxxxx> Subject: [PATCH] revoke: do s390 syscalls revoke: do s390 syscalls Signed-off-by: Serge E. Hallyn <serue@xxxxxxxxxx> (cherry picked from 9962b52d7bd7b70b99e7515d30b8217b0de491b3 commit) --- arch/s390/kernel/compat_wrapper.S | 11 +++++++++++ arch/s390/kernel/syscalls.S | 2 ++ include/asm-s390/unistd.h | 4 +++- 3 files changed, 16 insertions(+), 1 deletions(-) 3f0afa7b9a6b8c9ec930bdef73601f7260c79f47 diff --git a/arch/s390/kernel/compat_wrapper.S b/arch/s390/kernel/compat_wrapper.S index 71e54ef..b5c2bfa 100644 --- a/arch/s390/kernel/compat_wrapper.S +++ b/arch/s390/kernel/compat_wrapper.S @@ -1665,3 +1665,14 @@ sys_getcpu_wrapper: llgtr %r3,%r3 # unsigned * llgtr %r4,%r4 # struct getcpu_cache * jg sys_getcpu + + .globl sys_revokeat_wrapper +sys_revokeat_wrapper: + lgfr %r2,%r2 # int + llgtr %r3,%r3 # const char * + jg sys_revokeat + + .globl sys_frevoke_wrapper +sys_frevoke_wrapper: + llgfr %r2,%r2 # unsigned int + jg sys_frevoke diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S index a4ceae3..85a6673 100644 --- a/arch/s390/kernel/syscalls.S +++ b/arch/s390/kernel/syscalls.S @@ -321,3 +321,5 @@ SYSCALL(sys_vmsplice,sys_vmsplice,compat NI_SYSCALL /* 310 sys_move_pages */ SYSCALL(sys_getcpu,sys_getcpu,sys_getcpu_wrapper) SYSCALL(sys_epoll_pwait,sys_epoll_pwait,sys_ni_syscall) +SYSCALL(sys_revokeat,sys_revokeat,sys_revokeat_wrapper) +SYSCALL(sys_frevoke,sys_frevoke,sys_frevoke_wrapper) diff --git a/include/asm-s390/unistd.h b/include/asm-s390/unistd.h index fb6fef9..6651cb1 100644 --- a/include/asm-s390/unistd.h +++ b/include/asm-s390/unistd.h @@ -250,8 +250,10 @@ /* Number 310 is reserved for new sys_move_pages */ #define __NR_getcpu 311 #define __NR_epoll_pwait 312 +#define __NR_revokeat 313 +#define __NR_frevoke 314 -#define NR_syscalls 313 +#define NR_syscalls 315 /* * There are some system calls that are not present on 64 bit, some -- 1.1.6 - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
