From a90902531a06a030a252a07fbff7f45a189a64fe Mon Sep 17 00:00:00 2001 From: William Roberts Date: Tue, 11 Feb 2014 10:11:59 -0800 Subject: mm: Create utility function for accessing a tasks commandline value introduce get_cmdline() for retreiving the value of a processes proc/self/cmdline value. Acked-by: David Rientjes Acked-by: Stephen Smalley Acked-by: Richard Guy Briggs Signed-off-by: William Roberts Signed-off-by: Eric Paris --- mm/util.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) (limited to 'mm/util.c') diff --git a/mm/util.c b/mm/util.c index 808f375648e7..43b44199c5e3 100644 --- a/mm/util.c +++ b/mm/util.c @@ -413,6 +413,54 @@ unsigned long vm_commit_limit(void) * sysctl_overcommit_ratio / 100) + total_swap_pages; } +/** + * get_cmdline() - copy the cmdline value to a buffer. + * @task: the task whose cmdline value to copy. + * @buffer: the buffer to copy to. + * @buflen: the length of the buffer. Larger cmdline values are truncated + * to this length. + * Returns the size of the cmdline field copied. Note that the copy does + * not guarantee an ending NULL byte. + */ +int get_cmdline(struct task_struct *task, char *buffer, int buflen) +{ + int res = 0; + unsigned int len; + struct mm_struct *mm = get_task_mm(task); + if (!mm) + goto out; + if (!mm->arg_end) + goto out_mm; /* Shh! No looking before we're done */ + + len = mm->arg_end - mm->arg_start; + + if (len > buflen) + len = buflen; + + res = access_process_vm(task, mm->arg_start, buffer, len, 0); + + /* + * If the nul at the end of args has been overwritten, then + * assume application is using setproctitle(3). + */ + if (res > 0 && buffer[res-1] != '\0' && len < buflen) { + len = strnlen(buffer, res); + if (len < res) { + res = len; + } else { + len = mm->env_end - mm->env_start; + if (len > buflen - res) + len = buflen - res; + res += access_process_vm(task, mm->env_start, + buffer+res, len, 0); + res = strnlen(buffer, res); + } + } +out_mm: + mmput(mm); +out: + return res; +} /* Tracepoints definitions. */ EXPORT_TRACEPOINT_SYMBOL(kmalloc); -- cgit From 3b32123d734cb414e366b35a3b2142a995f9d1a0 Mon Sep 17 00:00:00 2001 From: Gideon Israel Dsouza Date: Mon, 7 Apr 2014 15:37:26 -0700 Subject: mm: use macros from compiler.h instead of __attribute__((...)) To increase compiler portability there is which provides convenience macros for various gcc constructs. Eg: __weak for __attribute__((weak)). I've replaced all instances of gcc attributes with the right macro in the memory management (/mm) subsystem. [akpm@linux-foundation.org: while-we're-there consistency tweaks] Signed-off-by: Gideon Israel Dsouza Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 3 ++- mm/nommu.c | 3 ++- mm/sparse.c | 4 +++- mm/util.c | 5 +++-- mm/vmalloc.c | 4 +++- 5 files changed, 13 insertions(+), 6 deletions(-) (limited to 'mm/util.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ed5072c64daa..c5aa43993364 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -3521,7 +3522,7 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address, #else /* !CONFIG_ARCH_WANT_GENERAL_HUGETLB */ /* Can be overriden by architectures */ -__attribute__((weak)) struct page * +struct page * __weak follow_huge_pud(struct mm_struct *mm, unsigned long address, pud_t *pud, int write) { diff --git a/mm/nommu.c b/mm/nommu.c index 5d3f3524bbdc..e68deff6d447 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -460,7 +461,7 @@ EXPORT_SYMBOL_GPL(vm_unmap_aliases); * Implement a stub for vmalloc_sync_all() if the architecture chose not to * have one. */ -void __attribute__((weak)) vmalloc_sync_all(void) +void __weak vmalloc_sync_all(void) { } diff --git a/mm/sparse.c b/mm/sparse.c index 38cad8fd7397..d1b48b691ac8 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -5,10 +5,12 @@ #include #include #include +#include #include #include #include #include + #include "internal.h" #include #include @@ -461,7 +463,7 @@ static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum) } #endif -void __attribute__((weak)) __meminit vmemmap_populate_print_last(void) +void __weak __meminit vmemmap_populate_print_last(void) { } diff --git a/mm/util.c b/mm/util.c index a24aa22f2473..d7813e6d4cc7 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1,6 +1,7 @@ #include #include #include +#include #include #include #include @@ -307,7 +308,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm) * If the architecture not support this function, simply return with no * page pinned */ -int __attribute__((weak)) __get_user_pages_fast(unsigned long start, +int __weak __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { return 0; @@ -338,7 +339,7 @@ EXPORT_SYMBOL_GPL(__get_user_pages_fast); * callers need to carefully consider what to use. On many architectures, * get_user_pages_fast simply falls back to get_user_pages. */ -int __attribute__((weak)) get_user_pages_fast(unsigned long start, +int __weak get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { struct mm_struct *mm = current->mm; diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 0fdf96803c5b..a7b522f4851d 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -27,7 +27,9 @@ #include #include #include +#include #include + #include #include #include @@ -2181,7 +2183,7 @@ EXPORT_SYMBOL(remap_vmalloc_range); * Implement a stub for vmalloc_sync_all() if the architecture chose not to * have one. */ -void __attribute__((weak)) vmalloc_sync_all(void) +void __weak vmalloc_sync_all(void) { } -- cgit