From: "Anthony G. Basile" Date: Sun, 7 Sep 2014 15:33:46 -0400 Subject: [PATCH] libc: add fallocate() and fallocate64() We add the Linux-specific function fallocate() which allows the user to directly manipulate allocate space for a file. fallocate() can operate in different modes, but the default mode is equivalent to posix_fallocate() which is specified in POSIX.1. Recent releases of e2fsprogs 1.42.11 and above expect fallocate64() to be available. Signed-off-by: Anthony G. Basile Signed-off-by: Bernhard Reutner-Fischer --- create mode 100644 libc/sysdeps/linux/common/fallocate.c create mode 100644 libc/sysdeps/linux/common/fallocate64.c create mode 100644 test/unistd/tst-fallocate.c create mode 100644 test/unistd/tst-fallocate64.c --- a/extra/Configs/Config.in +++ b/extra/Configs/Config.in @@ -952,8 +952,8 @@ config UCLIBC_LINUX_SPECIFIC default y help accept4(), bdflush(), - capget(), capset(), eventfd(), fstatfs(), - inotify_*(), ioperm(), iopl(), + capget(), capset(), eventfd(), fallocate(), + fstatfs(), inotify_*(), ioperm(), iopl(), madvise(), modify_ldt(), pipe2(), personality(), prctl()/arch_prctl(), pivot_root(), modify_ldt(), ppoll(), readahead(), reboot(), remap_file_pages(), --- a/include/fcntl.h +++ b/include/fcntl.h @@ -237,6 +237,38 @@ extern int __fcntl_nocancel (int fd, int libc_hidden_proto(__fcntl_nocancel) #endif +#if (defined __UCLIBC_LINUX_SPECIFIC__ && defined __USE_GNU) || defined _LIBC +/* Reserve storage for the data of a file associated with FD. This function + is Linux-specific. For the portable version, use posix_fallocate(). + Unlike the latter, fallocate can operate in different modes. The default + mode = 0 is equivalent to posix_fallocate(). + + Note: These declarations are used in posix_fallocate.c and + posix_fallocate64.c, so we expose them internally. + */ + +/* Flags for fallocate's mode. */ +# define FALLOC_FL_KEEP_SIZE 1 /* Don't extend size of file + even if offset + len is + greater than file size. */ +# define FALLOC_FL_PUNCH_HOLE 2 /* Create a hole in the file. */ + +# ifndef __USE_FILE_OFFSET64 +extern int fallocate (int __fd, int __mode, __off_t __offset, __off_t __len); +# else +# ifdef __REDIRECT +extern int __REDIRECT (fallocate, (int __fd, int __mode, __off64_t __offset, + __off64_t __len), + fallocate64); +# else +# define fallocate fallocate64 +# endif +# endif +# ifdef __USE_LARGEFILE64 +extern int fallocate64 (int __fd, int __mode, __off64_t __offset, __off64_t __len); +# endif +#endif + __END_DECLS #endif /* fcntl.h */ --- a/libc/sysdeps/linux/common/Makefile.in +++ b/libc/sysdeps/linux/common/Makefile.in @@ -61,6 +61,10 @@ CSRC-$(UCLIBC_LINUX_SPECIFIC) += \ vmsplice.c CSRC-$(if $(findstring yy,$(UCLIBC_LINUX_SPECIFIC)$(UCLIBC_HAS_LFS)),y) += \ sendfile64.c +# posix_fallocate() needs __libc_fallocate() from fallocate.c +# posix_fallocate64() needs __libc_fallocate64() from fallocate64.c +CSRC-$(if $(UCLIBC_LINUX_SPECIFIC)$(UCLIBC_HAS_ADVANCED_REALTIME),y,) += \ + fallocate.c $(filter fallocate64.c,$(CSRC-y)) # NPTL needs these internally: madvise.c CSRC-$(findstring y,$(UCLIBC_LINUX_SPECIFIC)$(UCLIBC_HAS_THREADS_NATIVE)) += madvise.c ifeq ($(UCLIBC_HAS_THREADS_NATIVE),y) --- /dev/null +++ b/libc/sysdeps/linux/common/fallocate.c @@ -0,0 +1,48 @@ +/* vi: set sw=4 ts=4: */ +/* + * fallocate() for uClibc - Based off of posix_fallocate() by Erik Andersen + * http://www.opengroup.org/onlinepubs/9699919799/functions/posix_fallocate.html + * + * Copyright (C) 2000-2006 Erik Andersen + * + * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball. + */ + +#include +#include +#include +#include + +#if defined __NR_fallocate +extern __typeof(fallocate) __libc_fallocate attribute_hidden; +int attribute_hidden __libc_fallocate(int fd, int mode, __off_t offset, __off_t len) +{ + int ret; + +# if __WORDSIZE == 32 + uint32_t off_low = offset; + uint32_t len_low = len; + /* may assert that these >>31 are 0 */ + uint32_t zero = 0; + INTERNAL_SYSCALL_DECL(err); + ret = (int) (INTERNAL_SYSCALL(fallocate, err, 6, fd, mode, + __LONG_LONG_PAIR (zero, off_low), + __LONG_LONG_PAIR (zero, len_low))); +# elif __WORDSIZE == 64 + INTERNAL_SYSCALL_DECL(err); + ret = (int) (INTERNAL_SYSCALL(fallocate, err, 4, fd, mode, offset, len)); +# else +# error your machine is neither 32 bit or 64 bit ... it must be magical +# endif + if (unlikely(INTERNAL_SYSCALL_ERROR_P (ret, err))) + return INTERNAL_SYSCALL_ERRNO (ret, err); + return 0; +} + +# if defined __UCLIBC_LINUX_SPECIFIC__ && defined __USE_GNU +strong_alias(__libc_fallocate,fallocate) +# if __WORDSIZE == 64 +strong_alias(__libc_fallocate,fallocate64) +# endif +# endif +#endif --- /dev/null +++ b/libc/sysdeps/linux/common/fallocate64.c @@ -0,0 +1,42 @@ +/* vi: set sw=4 ts=4: */ +/* + * fallocate() for uClibc - based off posix_fallocate() by Erik Andersen + * http://www.opengroup.org/onlinepubs/9699919799/functions/posix_fallocate.html + * + * Copyright (C) 2000-2006 Erik Andersen + * + * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball. + */ + +#include + +#include +#include +#include + +#if defined __NR_fallocate + +# if __WORDSIZE == 64 +/* Can use normal fallocate() */ +# elif __WORDSIZE == 32 +extern __typeof(fallocate64) __libc_fallocate64 attribute_hidden; +int attribute_hidden __libc_fallocate64(int fd, int mode, __off64_t offset, + __off64_t len) +{ + int ret; + INTERNAL_SYSCALL_DECL(err); + ret = (int) (INTERNAL_SYSCALL(fallocate, err, 6, fd, mode, + OFF64_HI_LO (offset), OFF64_HI_LO (len))); + if (unlikely(INTERNAL_SYSCALL_ERROR_P (ret, err))) + return INTERNAL_SYSCALL_ERRNO (ret, err); + return 0; +} + +# if defined __UCLIBC_LINUX_SPECIFIC__ && defined __USE_GNU +strong_alias(__libc_fallocate64,fallocate64) +# endif + +# else +# error your machine is neither 32 bit or 64 bit ... it must be magical +# endif +#endif --- a/libc/sysdeps/linux/common/posix_fallocate.c +++ b/libc/sysdeps/linux/common/posix_fallocate.c @@ -14,28 +14,10 @@ #include #if defined __NR_fallocate +extern __typeof(fallocate) __libc_fallocate attribute_hidden; int posix_fallocate(int fd, __off_t offset, __off_t len) { - int ret; - -# if __WORDSIZE == 32 - uint32_t off_low = offset; - uint32_t len_low = len; - /* may assert that these >>31 are 0 */ - uint32_t zero = 0; - INTERNAL_SYSCALL_DECL(err); - ret = (int) (INTERNAL_SYSCALL(fallocate, err, 6, fd, 0, - __LONG_LONG_PAIR (zero, off_low), - __LONG_LONG_PAIR (zero, len_low))); -# elif __WORDSIZE == 64 - INTERNAL_SYSCALL_DECL(err); - ret = (int) (INTERNAL_SYSCALL(fallocate, err, 4, fd, 0, offset, len)); -# else -# error your machine is neither 32 bit or 64 bit ... it must be magical -#endif - if (unlikely(INTERNAL_SYSCALL_ERROR_P (ret, err))) - return INTERNAL_SYSCALL_ERRNO (ret, err); - return 0; + return __libc_fallocate(fd, 0, offset, len); } # if defined __UCLIBC_HAS_LFS__ && __WORDSIZE == 64 strong_alias(posix_fallocate,posix_fallocate64) --- a/libc/sysdeps/linux/common/posix_fallocate64.c +++ b/libc/sysdeps/linux/common/posix_fallocate64.c @@ -18,22 +18,12 @@ # if __WORDSIZE == 64 /* Can use normal posix_fallocate() */ # elif __WORDSIZE == 32 +extern __typeof(fallocate64) __libc_fallocate64 attribute_hidden; int posix_fallocate64(int fd, __off64_t offset, __off64_t len) { - int ret; - uint32_t off_low = offset & 0xffffffff; - uint32_t off_high = offset >> 32; - uint32_t len_low = len & 0xffffffff; - uint32_t len_high = len >> 32; - INTERNAL_SYSCALL_DECL(err); - ret = (int) (INTERNAL_SYSCALL(fallocate, err, 6, fd, 0, - __LONG_LONG_PAIR (off_high, off_low), - __LONG_LONG_PAIR (len_high, len_low))); - if (unlikely(INTERNAL_SYSCALL_ERROR_P (ret, err))) - return INTERNAL_SYSCALL_ERRNO (ret, err); - return 0; + return __libc_fallocate64(fd, 0, offset, len); } # else -# error your machine is neither 32 bit or 64 bit ... it must be magical +# error your machine is neither 32 bit or 64 bit ... it must be magical # endif #endif --- a/test/.gitignore +++ b/test/.gitignore @@ -302,6 +302,8 @@ unistd/getcwd unistd/getopt unistd/getopt_long unistd/tstgetopt +unistd/tst-fallocate +unistd/tst-fallocate64 unistd/tst-posix_fallocate unistd/tst-posix_fallocate64 unistd/tst-preadwrite --- /dev/null +++ b/test/unistd/tst-fallocate.c @@ -0,0 +1,166 @@ +#include +#include + +#ifndef TST_FALLOCATE64 +# define stat64 stat +# define fstat64 fstat +# else +# ifndef O_LARGEFILE +# error no O_LARGEFILE but you want to test with LFS enabled +# endif +#endif + +static void do_prepare(void); +static int do_test(void); +#define PREPARE(argc, argv) do_prepare () +#define TEST_FUNCTION do_test () +#include + +static int fd; +static void +do_prepare (void) +{ + fd = create_temp_file ("tst-fallocate.", NULL); + if (fd == -1) + { + printf ("cannot create temporary file: %m\n"); + exit (1); + } +} + + +static int +do_test (void) +{ + struct stat64 st; + int c; + char garbage[4096]; + blkcnt_t blksb4; + + if (fstat64 (fd, &st) != 0) + { + puts ("1st fstat failed"); + return 1; + } + + if (st.st_size != 0) + { + puts ("file not created with size 0"); + return 1; + } + + /* This is the default mode which is identical to posix_fallocate(). + Note: we need a few extra blocks for FALLOC_FL_PUNCH_HOLE below. + While block sizes vary, we'll assume eight 4K blocks for good measure. */ + if (fallocate (fd, 0, 8 * 4096, 128) != 0) + { + puts ("1st fallocate call failed"); + return 1; + } + + if (fstat64 (fd, &st) != 0) + { + puts ("2nd fstat failed"); + return 1; + } + + if (st.st_size != 8 * 4096 + 128) + { + printf ("file size after 1st fallocate call is %llu, expected %u\n", + (unsigned long long int) st.st_size, 8u * 4096u + 128u); + return 1; + } + + /* Without FALLOC_FL_KEEP_SIZE, this would increaste the size of the file. */ + if (fallocate (fd, FALLOC_FL_KEEP_SIZE, 0, 16 * 4096) != 0) + { + puts ("2nd fallocate call failed"); + return 1; + } + + if (fstat64 (fd, &st) != 0) + { + puts ("3rd fstat failed"); + return 1; + } + + if (st.st_size != 8 * 4096 + 128) + { + printf ("file size changed in 2nd fallocate call to %llu, expected %u\n", + (unsigned long long int) st.st_size, 8u * 4096u + 128u); + return 1; + } + + /* Let's fill up the first eight 4k blocks with 'x' to force some allocations. */ + + memset(garbage, 'x', 4096); + for(c=0; c < 8; c++) + if(write(fd, garbage, 4096) == -1) + { + puts ("write failed"); + return 1; + } + + if (fstat64 (fd, &st) != 0) + { + puts ("4th fstat failed"); + return 1; + } + + blksb4 = st.st_blocks; + + /* Let's punch a hole in the entire file, turning it effectively into a sparse file. */ + if (fallocate (fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, 8 * 4096 + 128) != 0) + { + puts ("3rd fallocate call failed"); + return 1; + } + + if (fstat64 (fd, &st) != 0) + { + puts ("5th fstat failed"); + return 1; + } + + if (st.st_size != 8 * 4096 + 128) + { + printf ("file size after 3rd fallocate call is %llu, expected %u\n", + (unsigned long long int) st.st_size, 8u * 4096u + 128u); + return 1; + } + + /* The number of allocated blocks should decrease. I hope this works on + all filesystems! */ + if (st.st_blocks >= blksb4) + { + printf ("number of blocks after 3rd fallocate call is %lu, expected less than %lu\n", + (unsigned long int) st.st_blocks, blksb4); + return 1; + } + +#ifdef TST_FALLOCATE64 + /* We'll just do a mode = 0 test for fallocate64() */ + if (fallocate64 (fd, 0, 4097ULL, 4294967295ULL + 2ULL) != 0) + { + puts ("1st fallocate64 call failed"); + return 1; + } + + if (fstat64 (fd, &st) != 0) + { + puts ("6th fstat failed"); + return 1; + } + + if (st.st_size != 4097ULL + 4294967295ULL + 2ULL) + { + printf ("file size after 1st fallocate64 call is %llu, expected %llu\n", + (unsigned long long int) st.st_size, 4097ULL + 4294967295ULL + 2ULL); + return 1; + } +#endif + close (fd); + + return 0; +} + --- /dev/null +++ b/test/unistd/tst-fallocate64.c @@ -0,0 +1,2 @@ +#define TST_FALLOCATE64 +#include "tst-fallocate.c" --- a/test/unistd/Makefile.in +++ b/test/unistd/Makefile.in @@ -2,10 +2,13 @@ # Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. ifeq ($(UCLIBC_HAS_LFS),) -TESTS_DISABLED := tst-preadwrite64 tst-posix_fallocate64 +TESTS_DISABLED := tst-preadwrite64 tst-posix_fallocate64 tst-fallocate64 endif ifeq ($(UCLIBC_HAS_ADVANCED_REALTIME),) -TESTS_DISABLED := tst-posix_fallocate +TESTS_DISABLED := tst-posix_fallocate tst-fallocate64 +endif +ifeq ($(UCLIBC_LINUX_SPECIFIC),) +TESTS_DISABLED += tst-fallocate endif OPTS_getopt := -abcXXX -9 OPTS_getopt_long := --add XXX --delete YYY --verbose