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author | Lorenzo Stoakes <lstoakes@gmail.com> | 2016-12-14 15:06:55 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 16:04:09 -0800 |
commit | 8b7457ef9a9eb46cd1675d40d8e1fd3c47a38395 (patch) | |
tree | 485def76ab013b2609eb24762e4c39fc531c72d7 | |
parent | 5b56d49fc31dbb0487e14ead790fc81ca9fb2c99 (diff) | |
download | linux-8b7457ef9a9eb46cd1675d40d8e1fd3c47a38395.tar.gz linux-8b7457ef9a9eb46cd1675d40d8e1fd3c47a38395.tar.bz2 linux-8b7457ef9a9eb46cd1675d40d8e1fd3c47a38395.zip |
mm: unexport __get_user_pages_unlocked()
Unexport the low-level __get_user_pages_unlocked() function and replaces
invocations with calls to more appropriate higher-level functions.
In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked()
with get_user_pages_unlocked() since we can now pass gup_flags.
In async_pf_execute() and process_vm_rw_single_vec() we need to pass
different tsk, mm arguments so get_user_pages_remote() is the sane
replacement in these cases (having added manual acquisition and release
of mmap_sem.)
Additionally get_user_pages_remote() reintroduces use of the FOLL_TOUCH
flag. However, this flag was originally silently dropped by commit
1e9877902dc7 ("mm/gup: Introduce get_user_pages_remote()"), so this
appears to have been unintentional and reintroducing it is therefore not
an issue.
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20161027095141.2569-3-lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | include/linux/mm.h | 3 | ||||
-rw-r--r-- | mm/gup.c | 8 | ||||
-rw-r--r-- | mm/nommu.c | 8 | ||||
-rw-r--r-- | mm/process_vm_access.c | 12 | ||||
-rw-r--r-- | virt/kvm/async_pf.c | 10 | ||||
-rw-r--r-- | virt/kvm/kvm_main.c | 5 |
6 files changed, 25 insertions, 21 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index cc154454675a..7b2d14ed3815 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1280,9 +1280,6 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, struct vm_area_struct **vmas); long get_user_pages_locked(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, int *locked); -long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - struct page **pages, unsigned int gup_flags); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); int get_user_pages_fast(unsigned long start, int nr_pages, int write, @@ -865,9 +865,10 @@ EXPORT_SYMBOL(get_user_pages_locked); * caller if required (just like with __get_user_pages). "FOLL_GET" * is set implicitly if "pages" is non-NULL. */ -__always_inline long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - struct page **pages, unsigned int gup_flags) +static __always_inline long __get_user_pages_unlocked(struct task_struct *tsk, + struct mm_struct *mm, unsigned long start, + unsigned long nr_pages, struct page **pages, + unsigned int gup_flags) { long ret; int locked = 1; @@ -879,7 +880,6 @@ __always_inline long __get_user_pages_unlocked(struct task_struct *tsk, struct m up_read(&mm->mmap_sem); return ret; } -EXPORT_SYMBOL(__get_user_pages_unlocked); /* * get_user_pages_unlocked() is suitable to replace the form: diff --git a/mm/nommu.c b/mm/nommu.c index 9720e0bab029..c299a7fbca70 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -176,9 +176,10 @@ long get_user_pages_locked(unsigned long start, unsigned long nr_pages, } EXPORT_SYMBOL(get_user_pages_locked); -long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - struct page **pages, unsigned int gup_flags) +static long __get_user_pages_unlocked(struct task_struct *tsk, + struct mm_struct *mm, unsigned long start, + unsigned long nr_pages, struct page **pages, + unsigned int gup_flags) { long ret; down_read(&mm->mmap_sem); @@ -187,7 +188,6 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, up_read(&mm->mmap_sem); return ret; } -EXPORT_SYMBOL(__get_user_pages_unlocked); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags) diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index be8dc8d1edb9..84d0c7eada2b 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -88,7 +88,7 @@ static int process_vm_rw_single_vec(unsigned long addr, ssize_t rc = 0; unsigned long max_pages_per_loop = PVM_MAX_KMALLOC_PAGES / sizeof(struct pages *); - unsigned int flags = FOLL_REMOTE; + unsigned int flags = 0; /* Work out address and page range required */ if (len == 0) @@ -100,15 +100,19 @@ static int process_vm_rw_single_vec(unsigned long addr, while (!rc && nr_pages && iov_iter_count(iter)) { int pages = min(nr_pages, max_pages_per_loop); + int locked = 1; size_t bytes; /* * Get the pages we're interested in. We must - * add FOLL_REMOTE because task/mm might not + * access remotely because task/mm might not * current/current->mm */ - pages = __get_user_pages_unlocked(task, mm, pa, pages, - process_pages, flags); + down_read(&mm->mmap_sem); + pages = get_user_pages_remote(task, mm, pa, pages, flags, + process_pages, NULL, &locked); + if (locked) + up_read(&mm->mmap_sem); if (pages <= 0) return -EFAULT; diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index efeceb0a222d..3815e940fbea 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -76,16 +76,20 @@ static void async_pf_execute(struct work_struct *work) struct kvm_vcpu *vcpu = apf->vcpu; unsigned long addr = apf->addr; gva_t gva = apf->gva; + int locked = 1; might_sleep(); /* * This work is run asynchromously to the task which owns * mm and might be done in another context, so we must - * use FOLL_REMOTE. + * access remotely. */ - __get_user_pages_unlocked(NULL, mm, addr, 1, NULL, - FOLL_WRITE | FOLL_REMOTE); + down_read(&mm->mmap_sem); + get_user_pages_remote(NULL, mm, addr, 1, FOLL_WRITE, NULL, NULL, + &locked); + if (locked) + up_read(&mm->mmap_sem); kvm_async_page_present_sync(vcpu, apf); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 823544c166be..de102cae7125 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1418,13 +1418,12 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, npages = get_user_page_nowait(addr, write_fault, page); up_read(¤t->mm->mmap_sem); } else { - unsigned int flags = FOLL_TOUCH | FOLL_HWPOISON; + unsigned int flags = FOLL_HWPOISON; if (write_fault) flags |= FOLL_WRITE; - npages = __get_user_pages_unlocked(current, current->mm, addr, 1, - page, flags); + npages = get_user_pages_unlocked(addr, 1, page, flags); } if (npages != 1) return npages; |