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2011-08-03mm: clarify the radix_tree exceptional casesHugh Dickins
Make the radix_tree exceptional cases, mostly in filemap.c, clearer. It's hard to devise a suitable snappy name that illuminates the use by shmem/tmpfs for swap, while keeping filemap/pagecache/radix_tree generality. And akpm points out that /* radix_tree_deref_retry(page) */ comments look like calls that have been commented out for unknown reason. Skirt the naming difficulty by rearranging these blocks to handle the transient radix_tree_deref_retry(page) case first; then just explain the remaining shmem/tmpfs swap case in a comment. Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-03mm: a few small updates for radix-swapHugh Dickins
Remove PageSwapBacked (!page_is_file_cache) cases from add_to_page_cache_locked() and add_to_page_cache_lru(): those pages now go through shmem_add_to_page_cache(). Remove a comment on maximum tmpfs size from fsstack_copy_inode_size(), and add a comment on swap entries to invalidate_mapping_pages(). And mincore_page() uses find_get_page() on what might be shmem or a tmpfs file: allow for a radix_tree_exceptional_entry(), and proceed to find_get_page() on swapper_space if so (oh, swapper_space needs #ifdef). Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13thp: mincore transparent hugepage supportJohannes Weiner
Handle transparent huge page pmd entries natively instead of splitting them into subpages. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13thp: split_huge_page_mm/vmaAndrea Arcangeli
split_huge_page_pmd compat code. Each one of those would need to be expanded to hundred of lines of complex code without a fully reliable split_huge_page_pmd design. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25mincore: do nested page table walksJohannes Weiner
Do page table walks with the well-known nested loops we use in several other places already. This avoids doing full page table walks after every pte range and also allows to handle unmapped areas bigger than one pte range in one go. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25mincore: pass ranges as start,end address pairsJohannes Weiner
Instead of passing a start address and a number of pages into the helper functions, convert them to use a start and an end address. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25mincore: break do_mincore() into logical piecesJohannes Weiner
Split out functions to handle hugetlb ranges, pte ranges and unmapped ranges, to improve readability but also to prepare the file structure for nested page table walks. No semantic changes intended. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25mincore: cleanupsJohannes Weiner
This fixes some minor issues that bugged me while going over the code: o adjust argument order of do_mincore() to match the syscall o simplify range length calculation o drop superfluous shift in huge tlb calculation, address is page aligned o drop dead nr_huge calculation o check pte_none() before pte_present() o comment and whitespace fixes No semantic changes intended. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-12-15mm: hugetlb: fix hugepage memory leak in mincore()Naoya Horiguchi
Most callers of pmd_none_or_clear_bad() check whether the target page is in a hugepage or not, but mincore() and walk_page_range() do not check it. So if we use mincore() on a hugepage on x86 machine, the hugepage memory is leaked as shown below. This patch fixes it by extending mincore() system call to support hugepages. Details ======= My test program (leak_mincore) works as follows: - creat() and mmap() a file on hugetlbfs (file size is 200MB == 100 hugepages,) - read()/write() something on it, - call mincore() for first ten pages and printf() the values of *vec - munmap() and unlink() the file on hugetlbfs Without my patch ---------------- $ cat /proc/meminfo| grep "HugePage" HugePages_Total: 1000 HugePages_Free: 1000 HugePages_Rsvd: 0 HugePages_Surp: 0 $ ./leak_mincore vec[0] 0 vec[1] 0 vec[2] 0 vec[3] 0 vec[4] 0 vec[5] 0 vec[6] 0 vec[7] 0 vec[8] 0 vec[9] 0 $ cat /proc/meminfo |grep "HugePage" HugePages_Total: 1000 HugePages_Free: 999 HugePages_Rsvd: 0 HugePages_Surp: 0 $ ls /hugetlbfs/ $ Return values in *vec from mincore() are set to 0, while the hugepage should be in memory, and 1 hugepage is still accounted as used while there is no file on hugetlbfs. With my patch ------------- $ cat /proc/meminfo| grep "HugePage" HugePages_Total: 1000 HugePages_Free: 1000 HugePages_Rsvd: 0 HugePages_Surp: 0 $ ./leak_mincore vec[0] 1 vec[1] 1 vec[2] 1 vec[3] 1 vec[4] 1 vec[5] 1 vec[6] 1 vec[7] 1 vec[8] 1 vec[9] 1 $ cat /proc/meminfo |grep "HugePage" HugePages_Total: 1000 HugePages_Free: 1000 HugePages_Rsvd: 0 HugePages_Surp: 0 $ ls /hugetlbfs/ $ Return value in *vec set to 1 and no memory leaks. [akpm@linux-foundation.org: cleanup] [akpm@linux-foundation.org: build fix] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: David Rientjes <rientjes@google.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-14[CVE-2009-0029] System call wrappers part 14Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-28mm: remove nopageNick Piggin
Nothing in the tree uses nopage any more. Remove support for it in the core mm code and documentation (and a few stray references to it in comments). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-15[PATCH] mincore: vma crossing fixNick Piggin
My mincore also forgot about crossing vmas. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-15[PATCH] mincore: fill in results properlyNick Piggin
Paper bag time. Thanks to Randy for noticing that I didn't actually assign 'present' to anything. Unfortunately my original patch passed the few simple test cases I gave it, purely by coincidence. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-15[PATCH] mincore: CONFIG_SWAP=n fixNick Piggin
Fix mincore-anon patch to compile with CONFIG_SWAP=n Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] mm: mincore anonNick Piggin
Make mincore work for anon mappings, nonlinear, and migration entries. Based on patch from Linus Torvalds <torvalds@linux-foundation.org>. Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-17[PATCH] sys_mincore: s/max/min/Oleg Nesterov
fix a typo, sys_mincore() needs min(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Linus "I'm a moron" Torvalds <torvalds@osdl.org>
2006-12-16Fix up mm/mincore.c error value casesLinus Torvalds
Hugh Dickins correctly points out that mincore() is actually _supposed_ to fail on an unmapped hole in the user address space, rather than return valid ("empty") information about the hole. This just simplifies the problem further (I had been misled by our previous confusing and complicated way of doing mincore()). Also, in the unlikely situation that we can't allocate a temporary kernel buffer, we should actually return EAGAIN, not ENOMEM, to keep the "unmapped hole" and "allocation failure" error cases separate. Finally, add a comment about our stupid historical lack of support for anonymous mappings. I'll fix that if somebody reminds me after 2.6.20 is out. Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-16Fix incorrect user space access locking in mincore()Linus Torvalds
Doug Chapman noticed that mincore() will doa "copy_to_user()" of the result while holding the mmap semaphore for reading, which is a big no-no. While a recursive read-lock on a semaphore in the case of a page fault happens to work, we don't actually allow them due to deadlock schenarios with writers due to fairness issues. Doug and Marcel sent in a patch to fix it, but I decided to just rewrite the mess instead - not just fixing the locking problem, but making the code smaller and (imho) much easier to understand. Cc: Doug Chapman <dchapman@redhat.com> Cc: Marcel Holtmann <holtmann@redhat.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-19[PATCH] freepgt: sys_mincore ignore FIRST_USER_PGD_NRHugh Dickins
Remove use of FIRST_USER_PGD_NR from sys_mincore: it's inconsistent (no other syscall refers to it), unnecessary (sys_mincore loops over vmas further down) and incorrect (misses user addresses in ARM's first pgd). Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!