summaryrefslogtreecommitdiff
path: root/mm/gup.c
diff options
context:
space:
mode:
authorPeter Xu <peterx@redhat.com>2020-08-11 18:39:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-12 10:58:04 -0700
commit64019a2e467a288a16b65ab55ddcbf58c1b00187 (patch)
tree6c4272bf0188188b63023858edf85786a8f54817 /mm/gup.c
parenta2beb5f1efede6924a4258462a5660572e6ca864 (diff)
mm/gup: remove task_struct pointer for all gup code
After the cleanup of page fault accounting, gup does not need to pass task_struct around any more. Remove that parameter in the whole gup stack. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/gup.c')
-rw-r--r--mm/gup.c101
1 files changed, 42 insertions, 59 deletions
diff --git a/mm/gup.c b/mm/gup.c
index d5d44c68fa19..39e58df6925d 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -859,7 +859,7 @@ unmap:
* does not include FOLL_NOWAIT, the mmap_lock may be released. If it
* is, *@locked will be set to 0 and -EBUSY returned.
*/
-static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
+static int faultin_page(struct vm_area_struct *vma,
unsigned long address, unsigned int *flags, int *locked)
{
unsigned int fault_flags = 0;
@@ -962,7 +962,6 @@ static int check_vma_flags(struct vm_area_struct *vma, unsigned long gup_flags)
/**
* __get_user_pages() - pin user pages in memory
- * @tsk: task_struct of target task
* @mm: mm_struct of target mm
* @start: starting user address
* @nr_pages: number of pages from start to pin
@@ -1021,7 +1020,7 @@ static int check_vma_flags(struct vm_area_struct *vma, unsigned long gup_flags)
* instead of __get_user_pages. __get_user_pages should be used only if
* you need some special @gup_flags.
*/
-static long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
+static long __get_user_pages(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -1103,8 +1102,7 @@ retry:
page = follow_page_mask(vma, start, foll_flags, &ctx);
if (!page) {
- ret = faultin_page(tsk, vma, start, &foll_flags,
- locked);
+ ret = faultin_page(vma, start, &foll_flags, locked);
switch (ret) {
case 0:
goto retry;
@@ -1178,8 +1176,6 @@ static bool vma_permits_fault(struct vm_area_struct *vma,
/**
* fixup_user_fault() - manually resolve a user page fault
- * @tsk: the task_struct to use for page fault accounting, or
- * NULL if faults are not to be recorded.
* @mm: mm_struct of target mm
* @address: user address
* @fault_flags:flags to pass down to handle_mm_fault()
@@ -1207,7 +1203,7 @@ static bool vma_permits_fault(struct vm_area_struct *vma,
* This function will not return with an unlocked mmap_lock. So it has not the
* same semantics wrt the @mm->mmap_lock as does filemap_fault().
*/
-int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
+int fixup_user_fault(struct mm_struct *mm,
unsigned long address, unsigned int fault_flags,
bool *unlocked)
{
@@ -1256,8 +1252,7 @@ EXPORT_SYMBOL_GPL(fixup_user_fault);
* Please note that this function, unlike __get_user_pages will not
* return 0 for nr_pages > 0 without FOLL_NOWAIT
*/
-static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
- struct mm_struct *mm,
+static __always_inline long __get_user_pages_locked(struct mm_struct *mm,
unsigned long start,
unsigned long nr_pages,
struct page **pages,
@@ -1290,7 +1285,7 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
pages_done = 0;
lock_dropped = false;
for (;;) {
- ret = __get_user_pages(tsk, mm, start, nr_pages, flags, pages,
+ ret = __get_user_pages(mm, start, nr_pages, flags, pages,
vmas, locked);
if (!locked)
/* VM_FAULT_RETRY couldn't trigger, bypass */
@@ -1350,7 +1345,7 @@ retry:
}
*locked = 1;
- ret = __get_user_pages(tsk, mm, start, 1, flags | FOLL_TRIED,
+ ret = __get_user_pages(mm, start, 1, flags | FOLL_TRIED,
pages, NULL, locked);
if (!*locked) {
/* Continue to retry until we succeeded */
@@ -1437,7 +1432,7 @@ long populate_vma_page_range(struct vm_area_struct *vma,
* We made sure addr is within a VMA, so the following will
* not result in a stack expansion that recurses back here.
*/
- return __get_user_pages(current, mm, start, nr_pages, gup_flags,
+ return __get_user_pages(mm, start, nr_pages, gup_flags,
NULL, NULL, locked);
}
@@ -1521,7 +1516,7 @@ struct page *get_dump_page(unsigned long addr)
struct vm_area_struct *vma;
struct page *page;
- if (__get_user_pages(current, current->mm, addr, 1,
+ if (__get_user_pages(current->mm, addr, 1,
FOLL_FORCE | FOLL_DUMP | FOLL_GET, &page, &vma,
NULL) < 1)
return NULL;
@@ -1530,8 +1525,7 @@ struct page *get_dump_page(unsigned long addr)
}
#endif /* CONFIG_ELF_CORE */
#else /* CONFIG_MMU */
-static long __get_user_pages_locked(struct task_struct *tsk,
- struct mm_struct *mm, unsigned long start,
+static long __get_user_pages_locked(struct mm_struct *mm, unsigned long start,
unsigned long nr_pages, struct page **pages,
struct vm_area_struct **vmas, int *locked,
unsigned int foll_flags)
@@ -1596,8 +1590,7 @@ static bool check_dax_vmas(struct vm_area_struct **vmas, long nr_pages)
}
#ifdef CONFIG_CMA
-static long check_and_migrate_cma_pages(struct task_struct *tsk,
- struct mm_struct *mm,
+static long check_and_migrate_cma_pages(struct mm_struct *mm,
unsigned long start,
unsigned long nr_pages,
struct page **pages,
@@ -1675,7 +1668,7 @@ check_again:
* again migrating any new CMA pages which we failed to isolate
* earlier.
*/
- ret = __get_user_pages_locked(tsk, mm, start, nr_pages,
+ ret = __get_user_pages_locked(mm, start, nr_pages,
pages, vmas, NULL,
gup_flags);
@@ -1689,8 +1682,7 @@ check_again:
return ret;
}
#else
-static long check_and_migrate_cma_pages(struct task_struct *tsk,
- struct mm_struct *mm,
+static long check_and_migrate_cma_pages(struct mm_struct *mm,
unsigned long start,
unsigned long nr_pages,
struct page **pages,
@@ -1705,8 +1697,7 @@ static long check_and_migrate_cma_pages(struct task_struct *tsk,
* __gup_longterm_locked() is a wrapper for __get_user_pages_locked which
* allows us to process the FOLL_LONGTERM flag.
*/
-static long __gup_longterm_locked(struct task_struct *tsk,
- struct mm_struct *mm,
+static long __gup_longterm_locked(struct mm_struct *mm,
unsigned long start,
unsigned long nr_pages,
struct page **pages,
@@ -1731,7 +1722,7 @@ static long __gup_longterm_locked(struct task_struct *tsk,
flags = memalloc_nocma_save();
}
- rc = __get_user_pages_locked(tsk, mm, start, nr_pages, pages,
+ rc = __get_user_pages_locked(mm, start, nr_pages, pages,
vmas_tmp, NULL, gup_flags);
if (gup_flags & FOLL_LONGTERM) {
@@ -1745,7 +1736,7 @@ static long __gup_longterm_locked(struct task_struct *tsk,
goto out;
}
- rc = check_and_migrate_cma_pages(tsk, mm, start, rc, pages,
+ rc = check_and_migrate_cma_pages(mm, start, rc, pages,
vmas_tmp, gup_flags);
out:
memalloc_nocma_restore(flags);
@@ -1756,22 +1747,20 @@ out:
return rc;
}
#else /* !CONFIG_FS_DAX && !CONFIG_CMA */
-static __always_inline long __gup_longterm_locked(struct task_struct *tsk,
- struct mm_struct *mm,
+static __always_inline long __gup_longterm_locked(struct mm_struct *mm,
unsigned long start,
unsigned long nr_pages,
struct page **pages,
struct vm_area_struct **vmas,
unsigned int flags)
{
- return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas,
+ return __get_user_pages_locked(mm, start, nr_pages, pages, vmas,
NULL, flags);
}
#endif /* CONFIG_FS_DAX || CONFIG_CMA */
#ifdef CONFIG_MMU
-static long __get_user_pages_remote(struct task_struct *tsk,
- struct mm_struct *mm,
+static long __get_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -1790,20 +1779,18 @@ static long __get_user_pages_remote(struct task_struct *tsk,
* This will check the vmas (even if our vmas arg is NULL)
* and return -ENOTSUPP if DAX isn't allowed in this case:
*/
- return __gup_longterm_locked(tsk, mm, start, nr_pages, pages,
+ return __gup_longterm_locked(mm, start, nr_pages, pages,
vmas, gup_flags | FOLL_TOUCH |
FOLL_REMOTE);
}
- return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas,
+ return __get_user_pages_locked(mm, start, nr_pages, pages, vmas,
locked,
gup_flags | FOLL_TOUCH | FOLL_REMOTE);
}
/**
* get_user_pages_remote() - pin user pages in memory
- * @tsk: the task_struct to use for page fault accounting, or
- * NULL if faults are not to be recorded.
* @mm: mm_struct of target mm
* @start: starting user address
* @nr_pages: number of pages from start to pin
@@ -1862,7 +1849,7 @@ static long __get_user_pages_remote(struct task_struct *tsk,
* should use get_user_pages_remote because it cannot pass
* FAULT_FLAG_ALLOW_RETRY to handle_mm_fault.
*/
-long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+long get_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -1874,13 +1861,13 @@ long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
return -EINVAL;
- return __get_user_pages_remote(tsk, mm, start, nr_pages, gup_flags,
+ return __get_user_pages_remote(mm, start, nr_pages, gup_flags,
pages, vmas, locked);
}
EXPORT_SYMBOL(get_user_pages_remote);
#else /* CONFIG_MMU */
-long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+long get_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -1888,8 +1875,7 @@ long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
return 0;
}
-static long __get_user_pages_remote(struct task_struct *tsk,
- struct mm_struct *mm,
+static long __get_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -1909,11 +1895,10 @@ static long __get_user_pages_remote(struct task_struct *tsk,
* @vmas: array of pointers to vmas corresponding to each page.
* Or NULL if the caller does not require them.
*
- * This is the same as get_user_pages_remote(), just with a
- * less-flexible calling convention where we assume that the task
- * and mm being operated on are the current task's and don't allow
- * passing of a locked parameter. We also obviously don't pass
- * FOLL_REMOTE in here.
+ * This is the same as get_user_pages_remote(), just with a less-flexible
+ * calling convention where we assume that the mm being operated on belongs to
+ * the current task, and doesn't allow passing of a locked parameter. We also
+ * obviously don't pass FOLL_REMOTE in here.
*/
long get_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
@@ -1926,7 +1911,7 @@ long get_user_pages(unsigned long start, unsigned long nr_pages,
if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
return -EINVAL;
- return __gup_longterm_locked(current, current->mm, start, nr_pages,
+ return __gup_longterm_locked(current->mm, start, nr_pages,
pages, vmas, gup_flags | FOLL_TOUCH);
}
EXPORT_SYMBOL(get_user_pages);
@@ -1936,7 +1921,7 @@ EXPORT_SYMBOL(get_user_pages);
*
* mmap_read_lock(mm);
* do_something()
- * get_user_pages(tsk, mm, ..., pages, NULL);
+ * get_user_pages(mm, ..., pages, NULL);
* mmap_read_unlock(mm);
*
* to:
@@ -1944,7 +1929,7 @@ EXPORT_SYMBOL(get_user_pages);
* int locked = 1;
* mmap_read_lock(mm);
* do_something()
- * get_user_pages_locked(tsk, mm, ..., pages, &locked);
+ * get_user_pages_locked(mm, ..., pages, &locked);
* if (locked)
* mmap_read_unlock(mm);
*
@@ -1982,7 +1967,7 @@ long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
return -EINVAL;
- return __get_user_pages_locked(current, current->mm, start, nr_pages,
+ return __get_user_pages_locked(current->mm, start, nr_pages,
pages, NULL, locked,
gup_flags | FOLL_TOUCH);
}
@@ -1992,12 +1977,12 @@ EXPORT_SYMBOL(get_user_pages_locked);
* get_user_pages_unlocked() is suitable to replace the form:
*
* mmap_read_lock(mm);
- * get_user_pages(tsk, mm, ..., pages, NULL);
+ * get_user_pages(mm, ..., pages, NULL);
* mmap_read_unlock(mm);
*
* with:
*
- * get_user_pages_unlocked(tsk, mm, ..., pages);
+ * get_user_pages_unlocked(mm, ..., pages);
*
* It is functionally equivalent to get_user_pages_fast so
* get_user_pages_fast should be used instead if specific gup_flags
@@ -2020,7 +2005,7 @@ long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
return -EINVAL;
mmap_read_lock(mm);
- ret = __get_user_pages_locked(current, mm, start, nr_pages, pages, NULL,
+ ret = __get_user_pages_locked(mm, start, nr_pages, pages, NULL,
&locked, gup_flags | FOLL_TOUCH);
if (locked)
mmap_read_unlock(mm);
@@ -2665,7 +2650,7 @@ static int __gup_longterm_unlocked(unsigned long start, int nr_pages,
*/
if (gup_flags & FOLL_LONGTERM) {
mmap_read_lock(current->mm);
- ret = __gup_longterm_locked(current, current->mm,
+ ret = __gup_longterm_locked(current->mm,
start, nr_pages,
pages, NULL, gup_flags);
mmap_read_unlock(current->mm);
@@ -2908,10 +2893,8 @@ int pin_user_pages_fast_only(unsigned long start, int nr_pages,
EXPORT_SYMBOL_GPL(pin_user_pages_fast_only);
/**
- * pin_user_pages_remote() - pin pages of a remote process (task != current)
+ * pin_user_pages_remote() - pin pages of a remote process
*
- * @tsk: the task_struct to use for page fault accounting, or
- * NULL if faults are not to be recorded.
* @mm: mm_struct of target mm
* @start: starting user address
* @nr_pages: number of pages from start to pin
@@ -2932,7 +2915,7 @@ EXPORT_SYMBOL_GPL(pin_user_pages_fast_only);
* FOLL_PIN means that the pages must be released via unpin_user_page(). Please
* see Documentation/core-api/pin_user_pages.rst for details.
*/
-long pin_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
+long pin_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
@@ -2942,7 +2925,7 @@ long pin_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
return -EINVAL;
gup_flags |= FOLL_PIN;
- return __get_user_pages_remote(tsk, mm, start, nr_pages, gup_flags,
+ return __get_user_pages_remote(mm, start, nr_pages, gup_flags,
pages, vmas, locked);
}
EXPORT_SYMBOL(pin_user_pages_remote);
@@ -2974,7 +2957,7 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages,
return -EINVAL;
gup_flags |= FOLL_PIN;
- return __gup_longterm_locked(current, current->mm, start, nr_pages,
+ return __gup_longterm_locked(current->mm, start, nr_pages,
pages, vmas, gup_flags);
}
EXPORT_SYMBOL(pin_user_pages);
@@ -3019,7 +3002,7 @@ long pin_user_pages_locked(unsigned long start, unsigned long nr_pages,
return -EINVAL;
gup_flags |= FOLL_PIN;
- return __get_user_pages_locked(current, current->mm, start, nr_pages,
+ return __get_user_pages_locked(current->mm, start, nr_pages,
pages, NULL, locked,
gup_flags | FOLL_TOUCH);
}