Lines Matching +full:memory +full:- +full:mapped

12    physical frame each virtual page is mapped to.  It contains one 64-bit
16 * Bits 0-54 page frame number (PFN) if present
17 * Bits 0-4 swap type if swapped
18 * Bits 5-54 swap offset if swapped
19 * Bit 55 pte is soft-dirty (see
20 Documentation/admin-guide/mm/soft-dirty.rst)
21 * Bit 56 page exclusively mapped (since 4.2)
22 * Bit 57 pte is uffd-wp write-protected (since 5.13) (see
23 Documentation/admin-guide/mm/userfaultfd.rst)
25 * Bits 59-60 zero
26 * Bit 61 page is file-page or shared-anon (since 3.5)
31 In 4.0 and 4.1 opens by unprivileged fail with -EPERM. Starting from
38 precisely which pages are mapped (or in swap) and comparing mapped
41 Traditionally, bit 56 indicates that a page is mapped exactly once and bit
42 56 is clear when a page is mapped multiple times, even when mapped in the
46 mapped in the same process, even if the page is mapped multiple times in that
48 is *maybe* mapped in a different process. In some cases, a large allocation
49 might be treated as "maybe mapped by multiple processes" even though this
53 determine which areas of memory are actually mapped and llseek to
56 * ``/proc/kpagecount``. This file contains a 64-bit count of the number of
57 times each page is mapped, indexed by PFN. Some kernel configurations do
59 (e.g., THP) is mapped. In these configurations, the average number of
61 if any page of the large allocation is mapped, the returned value will
64 The page-types tool in the tools/mm directory can be used to query the
65 number of times a page is mapped.
67 * ``/proc/kpageflags``. This file contains a 64-bit set of flags for each
100 * ``/proc/kpagecgroup``. This file contains a 64-bit inode number of the
101 memory cgroup each page is charged to, indexed by PFN. Only available when
107 0 - LOCKED
110 7 - SLAB
111 The page is managed by the SLAB/SLUB kernel memory allocator.
114 10 - BUDDY
115 A free memory block managed by the buddy system allocator.
116 The buddy system organizes free memory in blocks of various orders.
119 15 - COMPOUND_HEAD
123 pages are hugeTLB pages (Documentation/admin-guide/mm/hugetlbpage.rst),
124 the SLUB etc. memory allocators and various device drivers.
127 16 - COMPOUND_TAIL
129 17 - HUGE
131 19 - HWPOISON
132 Hardware detected memory corruption on this page: don't touch the data!
133 20 - NOPAGE
135 21 - KSM
136 Identical memory pages dynamically shared between one or more processes.
137 22 - THP
138 Contiguous pages which construct THP of any size and mapped by any granularity.
139 23 - OFFLINE
141 24 - ZERO_PAGE
143 25 - IDLE
145 Documentation/admin-guide/mm/idle_page_tracking.rst).
147 a PTE. To make sure the flag is up-to-date one has to read
149 26 - PGTABLE
153 ---------------------
155 1 - ERROR
157 3 - UPTODATE
158 The page has up-to-date data.
159 ie. for file backed page: (in-memory data revision >= on-disk one)
160 4 - DIRTY
162 i.e. for file backed page: (in-memory data revision > on-disk one)
163 8 - WRITEBACK
167 ----------------------
169 5 - LRU
171 6 - ACTIVE
173 18 - UNEVICTABLE
174 The page is in the unevictable (non-)LRU list It is somehow pinned and
176 shmctl(SHM_LOCK) and mlock() memory segments.
177 2 - REFERENCED
179 9 - RECLAIM
181 11 - MMAP
182 A memory mapped page.
183 12 - ANON
184 A memory mapped page that is not part of a file.
185 13 - SWAPCACHE
186 The page is mapped to swap space, i.e. has an associated swap entry.
187 14 - SWAPBACKED
190 The page-types tool in the tools/mm directory can be used to query the
193 Exceptions for Shared Memory
197 swapped out. This makes swapped out pages indistinguishable from never-allocated
208 holes (none/non-allocated) by specifying the SEEK_DATA flag on the file where
212 mincore() can differentiate between pages in memory (present, including swap
213 cache) and out of memory (swapped out or none/non-allocated).
218 Reading from any of the files will return -EINVAL if you are not starting
219 the read on an 8-byte boundary (e.g., if you sought an odd number of bytes
222 Before Linux 3.11 pagemap bits 55-60 were used for "page-shift" (which is
224 after first clear of soft-dirty bits. Since Linux 4.2 they are used for
234 - Scan the address range and get the memory ranges matching the provided criteria.
236 - Write-protect the pages. The ``PM_SCAN_WP_MATCHING`` is used to write-protect
238 non-Async Write Protected pages are found. The ``PM_SCAN_WP_MATCHING`` can be
240 - Both of those operations can be combined into one atomic operation where we can
245 - ``PAGE_IS_WPALLOWED`` - Page has async-write-protection enabled
246 - ``PAGE_IS_WRITTEN`` - Page has been written to from the time it was write protected
247 - ``PAGE_IS_FILE`` - Page is file backed
248 - ``PAGE_IS_PRESENT`` - Page is present in the memory
249 - ``PAGE_IS_SWAPPED`` - Page is in swapped
250 - ``PAGE_IS_PFNZERO`` - Page has zero PFN
251 - ``PAGE_IS_HUGE`` - Page is PMD-mapped THP or Hugetlb backed
252 - ``PAGE_IS_SOFT_DIRTY`` - Page is soft-dirty
296 The ``PAGE_IS_WRITTEN`` flag can be considered as a better-performing alternative
297 of soft-dirty flag. It doesn't get affected by VMA merging of the kernel and hence
298 the user can find the true soft-dirty pages in case of normal pages. (There may
301 "PAGE_IS_WRITTEN" category is used with uffd write protect-enabled ranges to
302 implement memory dirty tracking in userspace:
307 3. The memory range is registered with ``UFFDIO_REGISTER_MODE_WP`` mode
309 4. Then any part of the registered memory or the whole memory region must