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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Jai0i+upLNHGSbXWrEDccPhs5qs6NoYZCZZXeqfHqR2N1Jfcdd495F63GCrN?= =?us-ascii?Q?92NETcYW3XY/chxXI60DsPJnQOOE570xA+51Aq155/LqpTUcMB3AHv4o3h0Z?= =?us-ascii?Q?d8jGnxNKl5Lp4Sbo0ykqqGCTzC2n35aCBumpbd4JdiA0EDzWSmzVz9MBQ1cg?= =?us-ascii?Q?/luLTCQovyg/J80g86kcNVxyWky5DM4a+7HVj4ioRLibVUQtSrqKsgX3Ckdz?= =?us-ascii?Q?0MG7E9ZziFCWZETnVYy5/wfKZpwo1AY+T24CuX2AyfU7e4MWdc4LbRqoctPL?= =?us-ascii?Q?4AzZnZarr3QCM5h74ff7B2yQH8CNrrg67i2nkSTZ7w2ICVS2MlO7tQ186fjD?= =?us-ascii?Q?Wt9P2kEkPuNzjCTsyDuEL1qCJU1dh71xLQUE2J/vdWKwePEhO9tUj2AUmp8x?= =?us-ascii?Q?lf4tn4kAalt2rQm2+qV+Jm3nSZRW3YClxyhvkl4msh4x+2wrjyQTtQJf44T+?= =?us-ascii?Q?SUn2HdWDdmUr/ZL1Tv7k/W1Ar61UQDrlR5AWfxxEAU1TnjY2npR8i7bvhtr6?= =?us-ascii?Q?vzbR0LtHMUj14TotvQSBpSajWtBclsUNsHbANcRvbPyYheH9AvQneBDkwDNh?= =?us-ascii?Q?65aW5ett922cua/BeXW3jwkkwanFeZyKhW6Sg1mOWRYkVYT4fazNrr4C535F?= =?us-ascii?Q?pTwjYy9rgzdUfP1c6t8CvLkDeko+1wuS66s1dDpe1ANpRD9YVlDPrqzpmquR?= =?us-ascii?Q?vqDoPCfmvo5fx5gvlbwv/VDHGHLzycdoL41t3WcC1ZvQDpSKd++t2XmmGlyO?= =?us-ascii?Q?5woh1wA7EG9sxbVKFBA+xe5cUdHgaaWl6rNm64PML7qHdeRK3C0uPn1mf0J9?= =?us-ascii?Q?sjYsVWAztXP6A6OO5xiExxBDFSJ7zM7T6cIKiD7/qAxardzxRG9MRUopywmd?= =?us-ascii?Q?baMUCB1MwB/1wree/MpudrGAR5OvzlTsGePLpL9S071jfsd0vzod3ndzgKnq?= =?us-ascii?Q?h5kgNSAO/EjeyGSs3iLYahHKjiaPBHjPJlvU0V1/+kGyjQlwILNM6T3qqqMc?= =?us-ascii?Q?6+Ru5lFWD8pH91cZYsScuSksybeDqQ6QZPIj86Yi/H5gLnrDqBMjwB5w/KkP?= =?us-ascii?Q?jg3and/BMuyKSZHVoD3XPoe3LwND/ppDuyoyz0XlJ2AG6zWbpOqGnfuDCX7N?= =?us-ascii?Q?3Wr57GCMrw9GqDUYrkdpmXtTiSV7uHoMM3GKgkimOkg9anJB5VhoSeJv/Sd1?= =?us-ascii?Q?YxIx7YDCVe/3fYF2dlveMg3hZV1TiXDhyHgwIEitIxqTt3fxHqfs1TnqyKTx?= =?us-ascii?Q?6FG1TMc+wEJquVBec49Yl3cfYfiObPPb/qqv0rL1sCCgLD3cg2YxMkUo5QpE?= =?us-ascii?Q?wCw5Qj5pOmkUI5dMGOXYWN1LrUIwSJqQmMLoesAklOxvTq1fYxDsfTAzOogJ?= =?us-ascii?Q?6z9UBw+fMkF/wQZTA+ffCjGlod5DLTO9GItcSI1MZ0LD27Nnv4bnGXbi3Z1o?= =?us-ascii?Q?1NsvLq7uODuIXEj90J0PCBYr5+2lvPxP+rGfP2tEvHJUfkb/NNGnehvLGxGB?= =?us-ascii?Q?q+aUlgw81SBKX1dOt/zbKcD6NYWcxWaaPwZUKWew4Pwx9jDOBpN/NVmdAd15?= =?us-ascii?Q?WUi55WDsGlYjHMFJeUnwBLWed3iEY5+VgtAhfMVKNPM/sJgZgs9YrwLbnPQ8?= =?us-ascii?Q?sg=3D=3D?= X-OriginatorOrg: garyguo.net X-MS-Exchange-CrossTenant-Network-Message-Id: ac1a9303-5802-4660-8abd-08dcc9b6b1f6 X-MS-Exchange-CrossTenant-AuthSource: LO2P265MB5183.GBRP265.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Aug 2024 12:16:08.8731 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: bbc898ad-b10f-4e10-8552-d9377b823d45 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: vXgqsH+zklM5Djd6Um3hLJm13vtuNlSrVmatpMq9m78PpTjXGq8h6WlPLihW4wgASxwFkUbfsC87lPSSL93oeA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LO2P265MB5757 On Fri, 16 Aug 2024 02:10:44 +0200 Danilo Krummrich wrote: > Separate `aligned_size` from `krealloc_aligned`. > > Subsequent patches implement `Allocator` derivates, such as `Kmalloc`, > that require `aligned_size` and replace the original `krealloc_aligned`. > > Reviewed-by: Alice Ryhl > Reviewed-by: Benno Lossin > Signed-off-by: Danilo Krummrich Reviewed-by: Gary Guo > --- > rust/kernel/alloc/allocator.rs | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-) > > diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs > index e6ea601f38c6..c83b6dff896d 100644 > --- a/rust/kernel/alloc/allocator.rs > +++ b/rust/kernel/alloc/allocator.rs > @@ -8,6 +8,17 @@ > > struct KernelAllocator; > > +/// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment. > +fn aligned_size(new_layout: Layout) -> usize { > + // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. > + let layout = new_layout.pad_to_align(); > + > + // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()` > + // which together with the slab guarantees means the `krealloc` will return a properly aligned > + // object (see comments in `kmalloc()` for more information). > + layout.size() > +} > + > /// Calls `krealloc` with a proper size to alloc a new object aligned to `new_layout`'s alignment. > /// > /// # Safety > @@ -15,13 +26,7 @@ > /// - `ptr` can be either null or a pointer which has been allocated by this allocator. > /// - `new_layout` must have a non-zero size. > pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: Flags) -> *mut u8 { > - // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. > - let layout = new_layout.pad_to_align(); > - > - // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()` > - // which together with the slab guarantees means the `krealloc` will return a properly aligned > - // object (see comments in `kmalloc()` for more information). > - let size = layout.size(); > + let size = aligned_size(new_layout); > > // SAFETY: > // - `ptr` is either null or a pointer returned from a previous `k{re}alloc()` by the