1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/ceph/ceph_debug.h> 3 4 #include <linux/module.h> 5 #include <linux/sched.h> 6 #include <linux/slab.h> 7 #include <linux/file.h> 8 #include <linux/namei.h> 9 #include <linux/writeback.h> 10 11 #include <linux/ceph/libceph.h> 12 13 void ceph_put_page_vector(struct page **pages, int num_pages, bool dirty) 14 { 15 int i; 16 17 for (i = 0; i < num_pages; i++) { 18 if (dirty) 19 set_page_dirty_lock(pages[i]); 20 put_page(pages[i]); 21 } 22 kvfree(pages); 23 } 24 EXPORT_SYMBOL(ceph_put_page_vector); 25 26 void ceph_release_page_vector(struct page **pages, int num_pages) 27 { 28 int i; 29 30 for (i = 0; i < num_pages; i++) 31 __free_pages(pages[i], 0); 32 kfree(pages); 33 } 34 EXPORT_SYMBOL(ceph_release_page_vector); 35 36 /* 37 * allocate a vector new pages 38 */ 39 struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags) 40 { 41 struct page **pages; 42 int i; 43 44 pages = kmalloc_array(num_pages, sizeof(*pages), flags); 45 if (!pages) 46 return ERR_PTR(-ENOMEM); 47 for (i = 0; i < num_pages; i++) { 48 pages[i] = __page_cache_alloc(flags); 49 if (pages[i] == NULL) { 50 ceph_release_page_vector(pages, i); 51 return ERR_PTR(-ENOMEM); 52 } 53 } 54 return pages; 55 } 56 EXPORT_SYMBOL(ceph_alloc_page_vector); 57 58 void ceph_copy_from_page_vector(struct page **pages, 59 void *data, 60 loff_t off, size_t len) 61 { 62 int i = 0; 63 size_t po = off & ~PAGE_MASK; 64 size_t left = len; 65 66 while (left > 0) { 67 size_t l = min_t(size_t, PAGE_SIZE-po, left); 68 69 memcpy(data, page_address(pages[i]) + po, l); 70 data += l; 71 left -= l; 72 po += l; 73 if (po == PAGE_SIZE) { 74 po = 0; 75 i++; 76 } 77 } 78 } 79 EXPORT_SYMBOL(ceph_copy_from_page_vector); 80 81 /* 82 * Zero an extent within a page vector. Offset is relative to the 83 * start of the first page. 84 */ 85 void ceph_zero_page_vector_range(int off, int len, struct page **pages) 86 { 87 int i = off >> PAGE_SHIFT; 88 89 off &= ~PAGE_MASK; 90 91 dout("zero_page_vector_page %u~%u\n", off, len); 92 93 /* leading partial page? */ 94 if (off) { 95 int end = min((int)PAGE_SIZE, off + len); 96 dout("zeroing %d %p head from %d\n", i, pages[i], 97 (int)off); 98 zero_user_segment(pages[i], off, end); 99 len -= (end - off); 100 i++; 101 } 102 while (len >= PAGE_SIZE) { 103 dout("zeroing %d %p len=%d\n", i, pages[i], len); 104 zero_user_segment(pages[i], 0, PAGE_SIZE); 105 len -= PAGE_SIZE; 106 i++; 107 } 108 /* trailing partial page? */ 109 if (len) { 110 dout("zeroing %d %p tail to %d\n", i, pages[i], (int)len); 111 zero_user_segment(pages[i], 0, len); 112 } 113 } 114 EXPORT_SYMBOL(ceph_zero_page_vector_range); 115